HomeMy WebLinkAbout10-26-2022 PC Agenda Packet
Planning Commission
AGENDA
Wednesday, October 26, 2022, 6:00 p.m.
Council Chambers, 990 Palm Street, San Luis Obispo
The City of San Luis Obispo has returned to in-person meetings. Zoom participation will not be
supported. For those attending in-person, City facilities will be at limited capacity and masks are
strongly recommended. Planning Commission meetings can be viewed remotely on Channel 20 and
the City’s YouTube Channel: http://youtube.slo.city
INSTRUCTIONS FOR PUBLIC COMMENT:
Public Comment prior to the meeting (must be received 3 hours in advance of the meeting):
Mail - Delivered by the U.S. Postal Service. Address letters to the City Clerk's Office at 990
Palm Street, San Luis Obispo, California, 93401.
Email - Submit Public Comments via email to advisorybodies@slocity.org. In the body of your
email, please include the date of the meeting and the item number (if applicable). Emails will not
be read aloud during the meeting.
Voicemail - Call (805) 781-7164 and leave a voicemail. Please state and spell your name, the
agenda item number you are calling about, and leave your comment. Verbal comments must be
limited to 3 minutes. Voicemails will not be played during the meeting.
*All correspondence will be archived and distributed to members, however, submissions received
after the deadline will not be processed until the following day.
Public Comment during the meeting:
Meetings have returned to an in-person format. To provide public comment during the meeting,
you must be present in the Council Chambers.
Electronic Visual Aid Presentation. To conform with the City's Network Access and Use Policy,
Chapter 1.3.8 of the Council Policies & Procedures Manual, members of the public who desire
to utilize electronic visual aids to supplement their oral presentation are encouraged to provide
display-ready material to the City Clerk by 12:00 p.m. on the day of the meeting. Contact the
City Clerk's Office at cityclerk@slocity.org or (805) 781-7100.
Pages
1.CALL TO ORDER
Vice Chair Kahn will call the Regular Meeting of the Planning Commission to
order.
2.OATH OF OFFICE
Deputy City Clerk Megan Wilbanks will administer the Oath of Office to newly
appointed Planning Commissioners, Justin Cooley and David Houghton.
3.ELECTION OF CHAIR DUE TO AN UNSCHEDULED VACANCY
As required by the Planning Commission Bylaws, in the event of an
unscheduled vacancy of the Chair position, the Commission must elect a
member to serve as Chair for the duration of the unexpired term, ending April 1,
2023.
Recommendation:
Elect a member of the Planning Commission to the position of Chair to serve the
duration of the unexpired term, ending April 1, 2023.
4.PUBLIC COMMENT FOR ITEMS NOT ON THE AGENDA
At this time, people may address the Commission about items not on the
agenda. Comments are limited to three minutes per person. Items raised at this
time are generally referred to staff and, if action by the Commission is
necessary, may be scheduled for a future meeting.
5.CONSENT
Matters appearing on the Consent Calendar are expected to be non-
controversial and will be acted upon at one time. A member of the public may
request the Planning Commission to pull an item for discussion. The public may
comment on any and all items on the Consent Agenda within the three-minute
time limit.
5.a.CONSIDERATION OF MINUTES - SEPTEMBER 14, 2022 PLANNING
COMMISSION MINUTES
5
Recommendation:
To approve the Planning Commission Minutes of September 14, 2022.
5.b.(GENP-0553-2022) GENERAL PLAN CONFORMITY REPORT FOR
THE ACQUISITION OF EASEMENTS REQUIRED FOR THE MID-
HIGUERA BYPASS PROJECT
9
Recommendation:
Adopt a Draft Resolution determining General Plan Conformance for the
acquisition of permanent and temporary easements required to
complete the Mid-Higuera Bypass Project (GENP-0553-2022).
6.STUDY SESSION
6.a.GENP-0436-2022 STUDY SESSION ON GENERAL PLAN CLIMATE
ADAPTATION AND SAFETY ELEMENT UPDATE
127
Recommendation:
Receive a presentation on the Workshop Draft of the General Plan
Climate Adaptation and Safety Element Update, including the Draft
Hazards and Vulnerability’s Report, review draft vision, goals, policies
and programs, and provide comments or direction as appropriate.
7.COMMENT AND DISCUSSION
7.a.INFORMATIONAL PRESENTATION ON "THE LINK" PROJECT
LOCATED AT 276 TANK FARM ROAD (SPEC-0451-2022, GENP-
0449-2022, EID-0450-2022)
The Planning Commission will receive an informational presentation to
introduce a proposed new specific plan area located at 276 Tank Farm
Road called “The Link” (SPEC-0451-2022, GENP-0449-2022, EID-
0450-2022). The project includes various entitlements (Annexation,
General Plan Amendment, Specific Plan, Subdivision, etc.) for a project
with 725 multifamily attached units, 69,150 square feet of retail mixed
use space, 279,700 square feet of professional and medical office uses,
209,000 square feet of industrial and warehouse space, and 237,200
square feet of mixed service commercial uses. Project Address: 276
Tank Farm Road; Case #: SPEC-0451-2022, GENP-0449-2022, EID-
0450-2022); Applicant: Covelop, Inc.
7.b.STAFF UPDATES AND AGENDA FORECAST
Receive a brief update from Housing Policy & Programs Manager
Teresa McClish.
8.ADJOURNMENT
The Planning Commission will hold a Special Meeting on November 16, 2022 at
6:00 p.m. in the Council Chambers at City Hall, 990 Palm Street, San Luis
Obispo. The Regular Meetings of November 9, 2022 and November 23, 2022
will be canceled.
LISTENING ASSISTIVE DEVICES for the hearing impaired--see the Clerk
The City of San Luis Obispo wishes to make all of its public meetings accessible
to the public. Upon request, this agenda will be made available in appropriate
alternative formats to persons with disabilities. Any person with a disability who
requires a modification or accommodation in order to participate in a meeting
should direct such request to the City Clerk’s Office at (805) 781-7100 at least
48 hours before the meeting, if possible. Telecommunications Device for the
Deaf (805) 781-7410.
Planning Commission meetings are televised live on Charter Channel 20 and on
the City's YouTube Channel: http://youtube.slo.city. Agenda related writings or
documents provided to the Planning Commission are available for public
inspection on the City’s website: https://www.slocity.org/government/mayor-and-
city-council/agendas-and-minutes.
1
Planning Commission Minutes
September 14, 2022, 6:00 p.m.
Council Chambers, 990 Palm Street, San Luis Obispo
Planning
Commissioners
Present:
Commissioner Emily Francis, Commissioner Michael Hopkins,
Commissioner Bob Jorgensen, Commissioner Juan Munoz-
Morris, Vice Chair Steve Kahn (two vacant seats)
City Staff Present: Housing Policy & Programs Manager Teresa McClish, Assistant
City Attorney Markie Kersten, Megan Wilbanks, Deputy City Clerk
_____________________________________________________________________
1. CALL TO ORDER
A Regular Meeting of the San Luis Obispo Planning Commission was called to
order on September 14, 2022 at 6:01 p.m. in the Council Chambers at City Hall,
990 Palm Street, San Luis Obispo, by Vice Chair Steve Kahn.
2. PUBLIC COMMENT FOR ITEMS NOT ON THE AGENDA
Public Comment:
None
--End of Public Comment--
3. CONSENT
3.a CONSIDERATION OF MINUTES - AUGUST 10, 2022 PLANNING
COMMISSION MINUTES
Motion By Commissioner Francis
Second By Commissioner Munoz-Morris
To approve the Planning Commission Minutes of August 10, 2022.
Ayes (5): Commissioner Francis, Commissioner Hopkins, Commissioner
Jorgensen, Commissioner Munoz-Morris, and Vice Chair Kahn (two
vacant seats)
CARRIED (5 to 0)
Page 5 of 669
2
4. PUBLIC HEARINGS
4.a 2223 MONTEREY ST. (ARCH-0327-2021) REVIEW OF A REVISED
PROJECT DESIGN FOR THE MOTEL INN, AN 83-ROOM HOTEL WITH
29 BUNGALOW GUESTROOM BUILDINGS, FOUR SMALL
OUTBUILDINGS, POOL AREA, AND ASSOCIATED SITE
IMPROVEMENTS
Vice Chair Kahn opened the Public Hearing
Public Comments:
None
--End of Public Comment--
Vice Chair Kahn closed the Public Hearing
Motion By Commissioner Munoz-Morris
Second By Commissioner Hopkins
To continue consideration of the item to a date uncertain to allow
additional time for staff and the applicant to review and address certain
items related to the information and analyses set out in the Initial Study
and Mitigated Negative Declaration and Addendum for the pro ject.
Ayes (5): Commissioner Francis, Commissioner Hopkins, Commissioner
Jorgensen, Commissioner Munoz-Morris, and Vice Chair Kahn (two vacant
seats)
CARRIED (5 to 0)
4.b 950 HIGH ST. & 1940 SANTA BARBARA (USE-0477-2022) ESTABLISH
A SAFE PARKING PROGRAM AT RAILROAD SQUARE TO PROVIDE
THOSE EXPERIENCING HOMELESSNESS WITH VEHICLES A SAFE
PLACE TO TEMPORARILY PARK OVERNIGHT TO FACILITATE THE
TRANSITION TO PERMANENT HOUSING
Housing Coordinator Kyle Bell announced that staff is recommending that
the Planning Commission continue the public hearing to a date uncertain
to allow the applicant team time to address concerns that were raised by
members of the community during a recent neighborhood meeting. He
informed the Commission that staff will continue to work with CAPSLO to
improve upon the management of the program and provide adequate
resources to the neighborhood to address concerns related to
homelessness.
Page 6 of 669
3
Vice Chair Kahn opened the Public Hearing
Public Comments:
Steve Rarig
Stephen Jarrett
Jim Trask
--End of Public Comment--
Vice Chair Kahn closed the Public Hearing
Motion By Commissioner Hopkins
Second By Commissioner Jorgensen
To continue consideration of the item to a date uncertain to allow the
applicant team time to address concerns that were raised by members of
the community during a recent neighborhood meeting. Staff will continue
to work with CAPSLO to improve upon the management of the program
and provide adequate resources to the neighborhood to address concerns
related to homelessness.
Ayes (5): Commissioner Francis, Commissioner Hopkins, Commissioner
Jorgensen, Commissioner Munoz-Morris, and Vice Chair Kahn (two vacant
seats)
CARRIED (5 to 0)
5. COMMENT AND DISCUSSION
5.a STAFF UPDATES AND AGENDA FORECAST
Housing Policy & Programs Manager Teresa McClish provided the
following update:
The September 28, 2022 Planning Commission Meeting will be
canceled.
Currently, there are no items scheduled for the October 12, 2022
Planning Commission Meeting, so it may be canceled as well.
Tentatively scheduled for the October 26, 2022 Planning
Commission Meeting, is a Study Session Item to receive an update
on the General Plan Safety Element and an informational
presentation on a new development project called the "The Link".
Page 7 of 669
4
Tentatively scheduled for the November 16, 2022 Planning
Commission Meeting, is development review for a project at 1422
Monterey St. (ARCH-0020-2022, AFFH-0021-2022) that includes
construction of a 5-story mixed-use building consisting of 4,366
square feet of commercial space and 106 residential units
dedicated for affordable housing, and a 3 -story parking garage.
Tentatively scheduled for the December 14, 2022 Planning
Commission Meeting, consideration of the General Plan Safety
Element Update.
Deputy City Clerk Megan Wilbanks provided the following update on
recruitment efforts for the two vacant seats on Planning Commission:
Seven applications were received for the two open seats and
recruitment is now closed.
Interviews with the Council Subcommittee Members, Vice Mayor
Christianson and Council Member Pease, are scheduled for
September 27, 2022.
If qualified applicants are selected for vacant seats, the full City
Council will make appointments at the October 18, 2022 Council
Meeting.
6. ADJOURNMENT
The meeting was adjourned at 6:22 p.m. The next Regular Meeting of the
Planning Commission is scheduled for October 12, 2022 at 6:00 p.m. in the
Council Chambers at City Hall, 990 Palm Street, San Luis Obispo. The Regular
Meeting of September 28, 2022 will be canceled.
_________________________
APPROVED BY PLANNING COMMISSION: XX/XX/2022
Page 8 of 669
PLANNING COMMISSION AGENDA REPORT
SUBJECT: GENERAL PLAN CONFORMITY REPORT FOR THE ACQUISITION OF
EASEMENTS REQUIRED FOR THE MID-HIGUERA BYPASS PROJECT
BY: Shelsie Moore, Supervising Civil Engineer FROM: Tyler Corey, Deputy Director
Phone Number: (805)783-7735 Phone Number: (805)781-7169
Email: smoore@slocity.org Email: tcorey@slocity.org
APPLICANT: City of San Luis Obispo REPRESENTATIVE: Shelsie Moore
RECOMMENDATION
Adopt a Draft Resolution determining General Plan Conformance for the acquisition of
permanent and temporary easements required to complete the Mid -Higuera Bypass
Project (GENP-0553-2022).
1.0 COMMISSION'S PURVIEW
Section 65402 of the California Government Code requires the local planning agency
make a finding of General Plan conformance whenever a governmental entity proposes
to acquire or dispose of a property. Specifically, Section 65402 requires that the location,
purpose, and extent of real property acquisition (and disposition) be submitted to and
reported upon by the planning agency having jurisdiction as to conformity with the City’s
adopted general plan (Cal. Gov’t Code § 65402(c)).
2.0 SUMMARY
San Luis Obispo has experienced catastrophic flooding due to the nature of its watershed.
Most recently, in 1995, flooding caused damage throughout the San Luis Obispo
watershed, with creeks breaching their banks and creek bank failures. In response to the
damage, and to protect residents, businesses, and infrastructure, the Ci ty requested
permits from regulatory agencies to repair the damage to public facilities. The Army Corps
of Engineers and other regulators requested the City prepare a comprehensive Waterway
Management Plan (WMP) that could be used as the basis for future project planning,
decision making, and permitting.
The Waterway Management Plan (WMP) preparation was approved by Council in the fall
of 1999. In January 2002, the WMP was presented to Council and direction was received
for various aspects of the program, which included flood protection levels, major capital
projects, and design policies. On October 21, 2003, Council adopted the WMP, a thre e-
volume document, which includes components for stream management and
maintenance, a drainage design, and a flood management plan identifying potential flood
management projects.
Meeting Date: 10/26/2022
Item Number: 3b
Time Estimate: N/A - Consent
Page 9 of 669
Item 3b
GENP-0553-2022
Planning Commission Report – 10/26/2022
Mid-Higuera Bypass Project
The Mid-Higuera Bypass Project is the highest priority project identified in the WMP and
is located along the stretch of the San Luis Obispo Creek between Marsh Street and
Madonna Road (See Figure 1). This project will increase flood protection by removing
sediment and creek vegetation overgrowth, creating pathways for flood waters to return
to the creek, creating flood bypass channels within City open space, widening narrow
sections of creek for increased capacity, and replacing the existing Bianchi Lane Bridge
with a larger span bridge in order to widen the creek and increase flow capacity at that
location.
Figure 1: Mid-Higuera Bypass Project Location
The County Flood Control and Water Conservation District Zone 9 Advisory Committee
(Zone 9) with contributing oversight from staff and members of the public from both the
City and County, oversees implementation of projects recommended in the WMP. Since
Zone 9 initially approved County funding for planning and design work on the Mid-Higuera
Bypass project, a feasibility study, a Final Supplemental Environmental Impact Report
(Final SEIR), and 90% level plans and specifications have been completed. The City is
coordinating with County of San Luis Obispo staff on environmental permit s for project
construction.
Page 10 of 669
Item 3b
GENP-0553-2022
Planning Commission Report – 10/26/2022
The next step is for the City to coordinate with adjacent property owners for areas where
the creek work impacts private property. There are 25 properties adjacent to the project
limits including six parcels that are owned by the City. The majority of the work is within
the City owned parcels, but some work will be required on private property. The City plans
to work with adjacent property owners to secure temporary and permanent easements to
complete the work.
Staff have identified seven properties that will require permanent and temporary
construction easements in order to construct the project improvements. These permanent
easements will be for creek channel widening work including widening necessary for the
replacement of Bianchi Lane Bridge and associated infrastructure and utilities. There are
twelve properties that will only need temporary construction easements , which are
necessary for creek cleanup, vegetation removal, new plantings, and temporary irrigation.
The parcels requiring easements are identified in Attachment B. The specific easement
boundaries will vary by parcel and are not yet identified at this time.
3.0 PREVIOUS REVIEW
On April 28, 2021, the Planning Commission reviewed and approved the Capital
Improvement Plan of the 2021-23 Financial Plan for General Plan Conformity, which
included Mid-Higuera Bypass (row 280), but the location, purpose, and extent of the
necessary easement acquisition was not specifically provided. Additionally, on May 25,
2022, the Planning Commission reviewed and approved the Capital Improvement Plan
from the FY 22-23 Budget Supplement for General Plan Conformity.
4.0 PROJECT ANALYSIS
The Mid-Higuera Bypass Project was listed under conformance with the Safety Element
during the review of the 2021-23 Capital Improvement Plan. Specifically, the project is in
compliance with the Safety Element 2.1 Policy S: Flood Hazard Avoidance and Reduc tion
Item B:
The City should allow flood waters to move through natural channels. Flow
should be accommodated by removing debris and man -made obstructions.
The City recognized that many natural channels cannot contain runoff from
a storm greater than a 25-year event. Areas flooded by storms as large as
a 100-year event will be mapped.
The Mid-Higuera Bypass project including all easements needed to complete the work is
in compliance with the Safety Element listed above. Staff recommends finding General
Plan Conformity for any easement needed along the project limits to complete the project.
The proposed temporary and permanent easements will fulfill the City’s Safety Element
Policy and help achieve the Safety Goal of minimizing damage to public and priva te
property due to flooding.
Page 11 of 669
Item 3b
GENP-0553-2022
Planning Commission Report – 10/26/2022
5.0 ENVIRONMENTAL REVIEW
A Final Supplemental Environmental Impact Report (SEIR) (Attachment C) was prepared
by County Staff for the project focusing on the following mitigations: biological resources,
cultural resources, air quality, visual resources, hazardous materials, drainage/erosion
and sedimentation, and noise. On August 21, 2018, San Luis Obispo County Board of
Supervisors certified the SEIR. SEIR State Clearinghouse Number is SCH2016021077.
In accordance with recommendations of the SEIR, County Staff are applying for permits
with the Water Resources Control Board, California Fish and Wildlife, and Army Corp of
Engineers.
6.0 OTHER DEPARTMENT COMMENTS
There is concurrence from the Administration and Utilities Departments on this project.
7.0 ALTERNATIVES
1. Continue consideration of the proposal, with direction to staff on items needed or
necessary information to make a decision on General Plan conformity.
2. Deny that the proposed easement acquisitions for the Mid-Higuera Bypass Project
are in conformance with the General Plan based on finding(s) of inconsistency with
the General Plan. Staff does not recommend this alternative as the project is a
critical safety improvement for flooding in the Mid-Higuera area.
8.0 ATTACHMENTS
A - Draft Planning Commission Resolution determining General Plan Conformance for
the acquisition of easements for the Mid-Higuera Bypass Project
B - Exhibit A to Draft Resolution - Mid-Higuera Bypass Parcels
C - Final Supplemental Environmental Impact Report (SEIR) without Appendices
Page 12 of 669
R ______
RESOLUTION NO. PC-XXXX-22
A RESOLUTION OF THE PLANNING COMMISSION OF THE CITY OF
SAN LUIS OBISPO, CALIFORNIA, DETERMINING GENERAL PLAN
CONFORMANCE FOR THE ACQUISITION OF PERMANENT AND
TEMPORARY EASEMENTS REQUIRED TO COMPLETE THE MID-
HIGUERA BYPASS PROJECT, AS REPRESENTED IN THE STAFF
REPORT AND ATTACHMENTS DATED OCTOBER 26, 2022 (GENP-
0553-2022)
WHEREAS, the Planning Commission of the City of San Luis Obispo conducted a public
meeting in the Council Chamber of City Hall, 990 Palm Street, San Luis Obispo, California, on
October 26, 2022, for the purpose of reviewing acquisitions of easements necessary for the Mid-
Higuera Bypass project for General Plan Conformity as required by California Government Code
Section 65402 (GENP-0553-2022); and
WHEREAS, notices of said public meeting were made at the time and in the manner
required by law; and
WHEREAS, the Planning Commission has duly considered all evidence and
recommendations by staff as presented in the staff report.
NOW, THEREFORE, BE IT RESOLVED by the Planning Commission of the City of
San Luis Obispo as follows:
SECTION 1. Findings. Based upon all the evidence, the Commission makes the
following findings:
1. The acquisition of easements for the Mid-Higuera Bypass Project will not harm the
general health, safety, and welfare of people living or working in the vicinity because
the proposed project is consistent with the General Plan Safety Element. The parcels
requiring easements are identified in Exhibit A. The specific easement boundaries will
vary by parcel and are not yet identified at this time.
SECTION 2. Environmental Review. A Final Supplemental Environmental Impact Report
(SEIR) was prepared by County Staff for the project focusing on the following mitigations:
biological resources, cultural resources, air quality, visual resources, hazardous materials,
drainage/erosion and sedimentation, and noise. On August 21, 2018, San Luis Obispo County
Board of Supervisors certified the SEIR. SEIR State Clearinghouse Number is SCH2016021077.
Page 13 of 669
PC Resolution No. _____ (2022 Series) Page 2
R _____
SECTION 3. Action. The Planning Commission does find and report that GENP-0553-
2022 conforms to the City of San Luis Obispo’s General Plan pursuant to California Government
Code Section 65402.
Upon motion of _______________________, seconded by _______________________,
and on the following roll call vote:
AYES:
NOES:
ABSENT:
The foregoing resolution was adopted this _____ day of _____________________ 2022.
____________________________________
Tyler Corey, Secretary
Planning Commission
Page 14 of 669
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BIANCHI PACIFIC PISMO ALLEYHWY 101101SOFFHWY 101ACCESSROAD101NONPARKER101NONMADONNA101NOFFMaxar, Microsoft city of san luis obispoMid-Higuera Bypass Parcels10/11/2022002-482-015 1405 GARDEN ST002-482-021 390 HIGUERA ST003-711-023 PO BOX 3609003-711-024 500 GIUSEPPE CT STE #2003-711-026 PO BOX 2299003-711-041 PO BOX 16009004-511-020 707 3RD ST 5TH FL004-741-001 27 SOUTH ST004-741-006 176 BROOK ST004-741-007 1192 SEABRIGHT AVE004-741-008 190 BROOK ST004-741-010 160 BROOKS STAPN AddressCity OwnedPermanent EasementTemporary EasementPermanent 002-482-007 1256 SYDNEY STPermanent 002-482-013 1405 GARDEN STPermanent 002-482-017 284 HIGUERA STPermanent 002-482-023 1405 GARDEN STPermanent 002-482-024 3162 ROSE AVEPermanent 002-482-027 4860 MEADOWLARK LANEPermanent 002-511-023 750 PISMO STEasement APN AddressCity Owned 002-482-025 990 PALM STCity Owned 002-482-026 990 PALM STCity Owned 003-711-025 990 PALM STCity Owned 004-511-018 990 PALM STCity Owned 004-741-004 990 PALM STCity Owned 002-482-012 990 PALM STEasement APN AddressTemporary Easement Permanent Easement City Owned ParcelsWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϭϱϯϬϬ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϮϭϯϵϬ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϯͲϳϭϭͲϬϮϯϯϰ^ŽƵƚŚ^ƚƌĞĞƚϬϬϯͲϳϭϭͲϬϮϰϮϲϰ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϯͲϳϭϭͲϬϮϲϮϱϮ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϯͲϳϭϭͲϬϰϭϮϯϲ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϰͲϱϭϭͲϬϮϬϱϬ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϬϭϮϯ^ŽƵƚŚ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϬϲϭϳϴƌŽŽŬ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϬϳϭϴϬƌŽŽŬ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϬϴϭϴϰƌŽŽŬ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϭϬϭϲϬƌŽŽŬ^ƚƌĞĞƚWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϬϳϯϬϰ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϭϯϮϴϬ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϭϳDĂĚŽŶŶĂϬϬϮͲϰϴϮͲϬϮϯϮϵϮ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϮϰϮϴϲ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϮϳϯϬϲ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϱϭϭͲϬϮϯϰϬϲ,ŝŐƵĞƌĂ^ƚƌĞĞƚWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϭϮϮϴϰ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϮͲϰϴϮͲϬϮϱKƉĞŶ^ƉĂĐĞϬϬϮͲϰϴϮͲϬϮϲϯϮϬ,ŝŐƵĞƌĂ^ƚƌĞĞƚϬϬϯͲϳϭϭͲϬϮϱϭϬ^ŽƵƚŚ^ƚƌĞĞƚϬϬϰͲϱϭϭͲϬϭϴϱ^ŽƵƚŚ^ƚƌĞĞƚϬϬϰͲϳϰϭͲϬϬϰϭϳϬƌŽŽŬ^ƚƌĞĞƚϮϴϰ,ŝŐƵĞƌĂ^ƚƌĞĞƚWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϭϱϯϬϬ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϮϭϯϵϬ,/'h Z^dZ dϬϬϯͲϳϭϭͲϬϮϯϯϰ^Khd,^dZ dϬϬϯͲϳϭϭͲϬϮϰϮϲϰ,/'h Z^dZ dϬϬϯͲϳϭϭͲϬϮϲϮϱϮ,/'h Z^dZ dϬϬϯͲϳϭϭͲϬϰϭϮϯϲ,/'h Z^dZ dϬϬϰͲϱϭϭͲϬϮϬϱϬ,/'h Z^dZ dϬϬϰͲϳϰϭͲϬϬϭϮϯ^Khd,^dZ dϬϬϰͲϳϰϭͲϬϬϲϭϳϰZKK<^dZ dϬϬϰͲϳϰϭͲϬϬϳϭϳϴZKK<^dZ dϬϬϰͲϳϰϭͲϬϬϴϭϴϬZKK<^dZ dϬϬϰͲϳϰϭͲϬϭϬϭϲϬZKK<^dZ dWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϬϳϯϬϰ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϭϯϮϴϬ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϭϳϮϴϰ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϮϯϮϵϮ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϮϰϮϴϲ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϮϳϯϬϲ,/'h Z^dZ dϬϬϮͲϱϭϭͲϬϮϯϰϬϲ,/'h Z^dZ dWEĚĚƌĞƐƐϬϬϮͲϰϴϮͲϬϭϮϬ,/'h Z^dZ dϬϬϮͲϰϴϮͲϬϮϱϬ,/',^dZ dϬϬϮͲϰϴϮͲϬϮϲϯϮϬ,/'h Z^dZ dϬϬϯͲϳϭϭͲϬϮϱϭϬ^Khd,^dZ dϬϬϰͲϱϭϭͲϬϭϴϱ^Khd,^dZ dϬϬϰͲϳϰϭͲϬϬϰϭϳϬZKK<^dZ dNote: The specific easement boundaries will vary by parcel and are not yet identified at this time. Mid-Higuera Bypass Parcels - Exhibit APage 15 of 669
Page 16 of 669
FINAL
SUPPLEMENTAL ENVIRONMENTAL IMPACT REPORT
FOR THE MID-HIGUERA BYPASS PROJECT
SCH# 2016021077
Prepared By:
San Luis Obispo County Flood Control and
Water Conservation District
County Government Center, Room 200
San Luis Obispo, CA 93408
August 2017
Page 17 of 669
FINAL
Supplemental Environmental Impact Report
for the
Mid-Higuera Bypass Project
SCH# 2016021077
Prepared By:
San Luis Obispo County Flood Control and
Water Conservation District
County Government Center, Room 200
San Luis Obispo, CA 93408
August 2017
Page 18 of 669
Executive Summary
ES-1 Mid-Higuera Bypass Project FSEIR
Executive Summary
Purpose of the EIR
The purpose of an Environmental Impact Report (EIR) is to provide State and local agencies as
well as the general public with detailed information on the potentially significant environmental
effects which a proposed project is likely to have, to list ways which the significant
environmental effects may be minimized, and indicate alternatives to the project. This
Supplemental Environmental Impact Report (SEIR) addresses the environmental effects of the
construction and operation of the Mid-Higuera Bypass Project (project). The information
presented here supplements the October, 2003 San Luis Obispo Creek Watershed Waterway
Management Plan Final Programmatic Environmental Impact Report/Environmental Impact
Statement (EIR/EIS).
This SEIR has been prepared in accordance with the California Environmental Quality Act
(CEQA) as amended, and the latest State Guidelines for the Implementation of CEQA. The
need for a SEIR is justified based upon the review of project-specific design, the completion of
project-specific technical reports, and the completion of an Initial Study for the project (refer to
Appendix A).
Project Location
The project is located within and adjacent to San Luis Obispo Creek between the Marsh Street
Bridge (upstream) and Madonna Road Bridge (downstream). It is bordered on the west by
Highway 101 and on the east by Higuera Street. It is located completely within the City of San
Luis Obispo (refer to the Vicinity Map, Site Map, and Appendix B).
Project Background
The Mid-Higuera Bypass Project was specifically discussed in the EIR/EIS as one of five Capital
Improvement Projects; however, it was determined that subsequent environmental review would
be required at such time as project-specific data was available for review.
Proposed Project
The Mid-Higuera Bypass Project (project) is proposed to increase the flood control capacity of
San Luis Obispo Creek (creek) between Marsh Street and Madonna Road due to the following
concerns:
x there is currently less than 25-year storm capacity in this stretch of the creek;
x significant bank erosion exists in some locations;
x there is localized sediment accumulation, particularly at the Marsh Street Bridge;
x a poor pool-to-riffle ratio exists;
x substantial invasive species and exotic plants are present; and
x there is a lack of continuity and/or diversity in native riparian vegetation.
Page 19 of 669
Executive Summary
ES-2 Mid-Higuera Bypass Project FSEIR
Vicinity Map
Page 20 of 669
Executive Summary
ES-3 Mid-Higuera Bypass Project FSEIR
Site Map
Page 21 of 669
Executive Summary
ES-4 Mid-Higuera Bypass Project FSEIR
The proposed project includes five components developed to directly address these issues,
including:
Bypass Channels. The project would include the construction of two bypass channels, the
Bianchi Bypass and the South Street Bypass. The bypass channels are proposed between the
creek and Highway 101. They have been designed to be active during larger storm events (i.e.,
they are designed to be “above” the Ordinary High Water Mark [OHWM] of the creek), and to
flow full during 25-year storm events. Vegetated rock slope protection as well as root wads/flow
deflectors would be installed at both the upstream and downstream transition areas between the
bypass channels and the creek.
Benches and Related Grading. In addition to the bypass channels, the capacity and functionality
of the creek channel would be expanded through the construction of four benches, by laying
back slopes at the “pinch point”, and through construction of a “flow return”. Similar to the
bypass channels, the four benches proposed would be excavated above the creek OHWM and
would reach approximately 20-30 feet wide. The maximum slopes above the benches would be
excavated no steeper than 2.5:1.
Marsh Street Sediment Removal. Significant sediment has accumulated on the upstream side of
the Marsh Street Bridge and within the three bridge barrels. Further, the upstream sediment has
formed an island that is blocking the largest center barrel. To address this issue, sediment will
be removed upstream of the bridge, within the bridge barrels, and downstream of the bridge.
The sediment would be removed to 1-foot above the creek water surface elevation at time of
construction. This strategy will preserve the existing low flow channel through the bridge. In
addition, the western bank will be sloped back to a 2.5:1 slope.
Bianchi Lane Bridge Replacement. The existing Bianchi Lane Bridge is an old bridge that was
relocated to its current position many years ago. It is relatively low and narrow, and as a result
can only accommodate flows from a 6-year storm event. The proposed new bridge will be a two-
span bridge with a higher deck elevation and will incorporate the start of the first bypass
channel. The new bridge will provide capacity for an approximately 23-year storm event. The
new bridge installation will include grading to accommodate the new road approaches.
Riparian Enhancement. Riparian enhancements have been incorporated for each of the
components described above. Vegetated rock slope protection would be installed at the
confluence of the creek channel and the bypass channels. At these locations, root wads would
also be installed to provide pools and habitat complexity to the creek. At the Bianchi Bypass
downstream transition area, rock flow deflectors will be installed to create pools and hydrologic
complexity.
Notice of Preparation
In accordance with the provisions of the State CEQA Guidelines, a Notice of Preparation (NOP)
for the project was distributed on February 19, 2016. The advertised comment period ended on
March 21, 2016. A total of five responses, including one from the State Clearinghouse, were
received. These responses are included in Appendix A.
Page 22 of 669
Executive Summary
ES-5 Mid-Higuera Bypass Project FSEIR
Draft Supplemental Environmental Impact Report
The Draft Environmental Impact Report (DSEIR) was released for public comment on
September 23, 2016 for a 45-day public review period. The review period closed on November
7, 2016. The District received four comment letters, three from public agencies, and one from a
member of the public. Appendix E of the Final EIR describes persons, organizations, and public
agencies commenting on the DSEIR; verbatim comments received through the EIR process;
and responses by the lead agency to comments received. The comments did not result in any
significant new information or substantial revisions to the DSEIR.
Significant Environmental Impacts Identified
Table ES-1 shows each impact identified and all mitigation measures recommended to reduce
or avoid impacts. The most significant potential impacts identified in this EIR include:
Aesthetic Resources. The project proposes to revegetate the site after construction, although it
may take 5-10 years or more before the vegetation provides the screening of urban uses from
Highway 101 as it currently does.
Biological Resources. These impacts would include Impacts to the San Luis Obispo Creek
riparian corridor from construction, including temporary dewatering, tree and vegetation
removal, impacts to special-status wildlife species, and the potential to result in erosion and
sedimentation of the creek.
Hazards and Hazardous Materials. Hazardous materials have been identified within the project
corridor and they are likely to be encountered during construction of the project.
All impacts identified in the EIR can be reduced to a level of insignificance with mitigation.
Project Alternatives
Despite the fact that the 2003 EIR/EIS considered a reasonable range of alternatives to the Mid-
Higuera Bypass project specifically, Chapter 6 of the SEIR includes discussion of additional
alternatives in an attempt to reduce the severity of the short-term construction-related impacts
identified. These alternatives include:
1. Land Purchase/Business Relocation - Purchasing the properties along Higuera Street
most vulnerable to flooding, thereby reducing the flood risk;
2. Marsh Street Bridge Replacement - Reconstructing the Marsh Street Bridge and
Highway 101 interchange;
3. No Project Alternative – This alternative is required by CEQA, and in this case would
include periodic maintenance of the creek reach, including the vegetation and sediment
management that is already periodically performed by the County; and
4. Phased Project – Phasing construction over multiple years to reduce short-term
construction-related impacts to noise, air quality and traffic, as well as to minimize
disturbance to biological resources within the creek channel in any single year.
The alternatives analysis concludes that the proposed project with all mitigation applied may be
the environmentally superior alternative, or at least be the environmentally equivalent of the
phased project alternative.
Page 23 of 669
Executive Summary
ES-6 Mid-Higuera Bypass Project FSEIR
Impact Summary Table
The table on the following pages provides a summary of the potential impacts of the proposed
project. Also summarized in these tables are the mitigation measures associated with each
impact that are to be implemented by the project applicant in order to reduce the environmental
impacts to a level of insignificance. In accordance with CEQA, the Summary Table identifies the
types of potential impacts described in EIRs and those specifically associated with the proposed
development.
Class I Impacts—Significant environmental impacts that cannot be fully mitigated or avoided.
The decision maker must adopt a “Statement of Overriding Considerations” as required under
CEQA Guidelines Section 15093 if the project is approved. No Class I impacts have been
identified.
Class II Impacts—Significant environmental impacts that can be feasibly mitigated or avoided.
The decision maker must issue “Findings” under CEQA Guidelines §15091(a) if the project is
approved. All Class II impacts identified are described in the table below.
Class III Impacts—Environmental impacts that are adverse but not significant for which the
decision maker does not have to adopt “Findings” under CEQA. All Class II impacts identified in
this EIR would become Class III impacts with the adoption of the recommended mitigation.
Class IV Effect—An effect that would be beneficial, and would reduce existing environmental
impacts or hazards. The proposed project would potentially have beneficial impacts to water
resources because it would result in the removal of potentially hazardous soils and decrease the
risk of flooding; however, these potentially beneficial impacts are not specifically described in
the tables below.
Page 24 of 669
Executive Summary ES-7 Mid-Higuera Bypass Project Final SEIR Table ES-1 Potentially Significant Impacts that can be Feasibly Mitigated (Class II Impacts) Impact Duration Recommended Mitigation Measures Impact Class after Mitigation Applied Aesthetic Resources AR Impact 1 The project would cause a noticeable change to the visual environment of the site and its surroundings due to a loss of vegetative character, visibility of engineered channels and slope protection, and increased visibility to the development along Higuera Street, South Street and the Caltrans building north of Madonna Road as seen from Highway 101. Short and medium-term AR-mm-1 Prior to initiation of the project, the District shall ensure that revised grading and site plans show the following: 1. All channel benches and bypass channels shall employ contour grading design and construction techniques to reduce their engineered appearance. All grade breaks shall be rounded and avoid angular slope-interface. 2. All top-of-slope hinge-points shall employ slope-rounding where doing so would not adversely affect existing vegetation. Class III AR-mm-2 Prior to initiation of the project, the District shall ensure preparation and implementation of a planting plan, which shall supplement the Vegetation Enhancement Plan, be developed and signed by a licensed landscape architect or restoration specialist, and include the following: 1. Visual screen planting between the easternmost extent of channel and bench grading and the adjacent parcels east of the project, between Stations 13+50 and 17+00, and between Stations 22+50 and 27+00. 2. Screen planting shall be a mix of evergreen trees and shrubs placed in natural-looking patterns. 3. Trees planted for screening along the fence shall be planted from primarily 24-inch box containers. Shrubs shall be planted from minimum 5-gallon containers. 4. Screen planting shall include the appropriate number and density of plants to achieve a minimum of 90 percent visual screening of the adjacent development as seen from Highway 101 within five years. 5. Additional planting between the bypass channels and the Highway 101 right-of-way, to the maximum extent possible. 6. Planting along Highway 101 shall be a mix of evergreen trees and shrubs placed in natural-looking patterns. 7. Trees planted along Highway 101 shall be planted from primarily 24-inch box containers. Shrubs shall be planted from minimum 5-gallon containers. AQ Impact 1 Project construction activities would result in emissions levels that exceed SLOAPCD thresholds. Short-term AQ-mm 1 A Construction Activity Management Plan (CAMP) shall be prepared for the proposed project. The CAMP shall be submitted to the SLOAPCD for review and approval prior to the start of construction. The CAMP shall include, at a minimum, the following elements: 1. Identification of the project construction schedules. To the extent possible, construction activities should be phased to minimize cumulative increases of daily emissions from multiple activities. 2. Identification of schedules for truck hauling activities and associated haul routes. Haul routes and schedules that would have the least impact to nearby sensitive receptors shall be selected. Construction activities and haul truck trips should be scheduled during non-peak hours (as determined by the Public Works Director) to reduce peak hour emissions. 3. Identification of construction-equipment permitting requirements. Portable equipment, 50 horsepower (hp) or greater, used during construction activities may require California statewide portable equipment registration (issued by the California Air Resources Board) or a SLOAPCD permit. Examples of such equipment may include, but are not limited to, standby generators, material processing equipment (e.g., crushers, conveyors, portable batch plants, tub grinders, trammel screens). 4. Identification of a designated person or persons responsible for implementation of the CAMP and emissions monitoring and compliance. The designated individual(s) shall be responsible for monitoring of fugitive dust emissions and the implementation/enhancement of measures, as necessary, to minimize dust complaints, reduce visible emissions below the Class III Page 25 of 669
Executive Summary ES-8 Mid-Higuera Bypass Project Final SEIR SLOAPCD’s limit of 20% opacity for greater than 3 minutes in any 60-minute period. Their duties shall include holidays and weekend periods when work may not be in progress. The name and telephone number of such persons shall be provided to the SLOAPCD Compliance Division prior to the start of any grading, earthwork or demolition. 5. Tabulation of on-road and off-road construction equipment. Emissions shall be quantified in accordance with SLOAPCD-recommended methodologies based on project-specific construction requirements (e.g., construction schedules, construction vehicle trips, and off-road equipment fleet to be used during project construction. 6. Identification of fugitive dust and mobile-source emission control measures to be implemented sufficient to demonstrate compliance with SLOAPCD’s CEQA thresholds of significance and to minimize nuisance impacts at nearby sensitive receptors. AQ Impact 2 The project could expose sensitive receptors to pollutants such as lead and fugitive dust. Short-term AQ-mm 2 The following measures shall be implemented during construction to reduce potential expose of sensitive receptors to substantial pollutant concentrations. These measures shall also be included in the CAMP to be prepared for this project 1. Demolition of onsite structures shall comply with the National Emission Standards for Hazardous Air Emissions (NESHAP) requirements (NESHAP, 40 CFR, Part 61, Subpart M) for the demolition of existing structures. The SLOAPCD is delegated authority by the Environmental Protection Agency (EPA) to implement the Federal Asbestos NESHAP. Prior to demolition of onsite structures, the SLOAPCD shall be notified, per NESHAP requirements. 2. If during demolition of Bianchi Lane Bridge, paint is separated from the construction materials (e.g. chemically or physically), the paint waste will be evaluated independently from the building material by a qualified hazardous materials inspector to determine its proper management. All hazardous materials shall be handled and disposed in accordance with local, state and federal regulations. 3. According to the Department of Toxic Substances Control (DTSC), if paint is not removed from the building material during demolition (and is not chipping or peeling), the material can be disposed of as construction debris (a non-hazardous waste). The landfill operator will be contacted prior to disposal of building material debris to determine any specific requirements the landfill may have regarding the disposal of lead-based paint materials. The disposal of demolition debris shall comply with any such requirements. 4. On-road diesel vehicles shall comply with Section 2485 of Title 13 of the California Code of Regulations. In general, the regulation specifies that drivers of said vehicles: x Shall not idle the vehicle’s primary diesel engine for greater than 5 minutes at any location, except as noted in Subsection (d) of the regulation; and, x Shall not operate a diesel-fueled auxiliary power system to power a heater, air conditioner, or any ancillary equipment on that vehicle during sleeping or resting in a sleeper berth for greater than 5.0 minutes at any location when within 1,000 feet of a restricted area, except as noted in Subsection (d) of the regulation. x Off-road diesel equipment shall comply with the 5-minute idling restriction identified in Section 2449(d)(2) of the California Air Resources Board’s In-Use off-Road Diesel regulation. x Signs must be posted in the designated queuing areas and job sites to remind drivers and operators of the state’s 5 minute idling limit. x Construction truck trips shall be scheduled, to the extent feasible, to occur during non-peak hours. x The burning of vegetative material shall be prohibited. 5. Should hydrocarbon contaminated soil be encountered during construction activities, the SLOAPCD shall be notified as soon as possible and no later than 48 hours after affected material is discovered to determine if a SLOAPCD Permit will be required. In addition, the following measures shall be implemented immediately after contaminated soil is discovered: x Covers on storage piles shall be maintained in place at all times in areas not actively involved in soil addition or removal; x Contaminated soil shall be covered with at least six inches of packed uncontaminated soil or other TPH –non-permeable barrier such as plastic tarp. No headspace shall be allowed where vapors could accumulate; x Covered piles shall be designed in such a way to eliminate erosion due to wind or water. No openings in the covers are permitted; x The air quality impacts from the excavation and haul trips associated with removing the contaminated soil must be Class III Page 26 of 669
Executive Summary ES-9 Mid-Higuera Bypass Project Final SEIR evaluated and mitigated if total emissions exceed the SLOAPCD’s construction phase thresholds; x During soil excavation, odors shall not be evident to such a degree as to cause a public nuisance; and, x Clean soil must be segregated from contaminated soil. BR-Impact 1 California red-legged frog may be directly impacted during construction activities. Short-term BR-mm 1 Through the USACE permit process, conduct consultation with the USFWS to develop avoidance and minimization measures for the CRLF. These measures may include, for example, the measures described in the 1999 CRLF Programmatic Biological Opinion between the USFWS and the USACE. Class III BR-Impact 2 South-central California coast steelhead may be directly impacted during construction activities. Short-term BR-mm 2 Construction requiring stream dewatering, stream crossings, or work in the channel bed will not start before June 1. Upstream and downstream passage for fish, including juvenile steelhead, will be provided through or around construction sites at all times. Cofferdams will be installed to divert streamflow around each in-stream construction area. Class III BR-mm 3 Through the USACE permit process, conduct consultation with the NMFS to develop avoidance and minimization measures for steelhead. These measures may include, for example, having a qualified biologist onsite during the installation of cofferdams and during the cofferdam dewatering process to capture and move trapped salmonids and other fish as well as identifying the appropriate procedures for relocating fish. Protocols for the capture, handling, and release of fish will be developed in cooperation with NMFS and CDFW and implemented during project construction. Class III BR-Impact 3 Implementation of the project would potentially result in long-term adverse impacts to the habitat value of the creek for steelhead within the project area. Long-term BR-mm 4 Prior to construction the project plans shall be revised to show the bypass channels sloped towards the “inside” bank to minimize the potential for ponding water. BR-mm 5 Prior to construction the project plans shall incorporate additional boulder clusters or similar features into the design of the transition areas. BR-mm 6 At the appropriate time following applicable storm events, the bypass channels shall be inspected to determine the potential for ponded water and to confirm no fish have been stranded. In the event that special-status fish are observed stranded in the bypass channels, they shall be relocated by a qualified biologist consistent with necessary permits and authorizations. BR-mm 7 Prior to construction and following construction at appropriate intervals, the habitat assessments consistent with those performed for the WMP shall be conducted by qualified biologists. These efforts shall be described in and coordinated with habitat restoration monitoring to be described in the HMMP for the project. BR-Impact 4 Removal of larger stands of eucalyptus within the project corridor would potentially impact overwintering monarch butterflies. Short-term BR-mm 8 To avoid impacts to monarch butterflies, construction shall be avoided as feasible during the monarch butterfly wintering period (November to February). However, if work is scheduled to occur during this time, the project corridor shall first be surveyed for overwintering monarch butterfly. If substantial monarch butterfly population is observed, tree removal shall cease within 200 feet of the population, and sufficient dust control measures shall be implemented to minimize dust emissions and associated impacts to any eucalyptus groves within or directly adjacent to project-related ground disturbance. Class III BR Impact 5 Demolition of the Bianchi Lane Bridge and tree removal would potentially impact roosting bats. Short-term BR-mm 9 Prior to construction, one daytime and one night-time pre-construction surveys shall be conducted by qualified biologists no more than 30 days prior to construction to determine if bats are day or night roosting in the project area. The biologist(s) conducting the preconstruction surveys will also identify the nature of the bat utilization of the area (i.e., no roosting, night roost, day roost, maternity roost). If bats are found to be roosting in the surveyed areas, the following measures will be implemented during construction: 1. If there is only night roosting by bats and the roost substrate will not be impacted, work may proceed as normal provided that no night-time work is scheduled. 2. If there is day roosting by bats (or night roosting and work during nighttime), qualified biologists shall monitor any construction activities within 100 ft for disturbance to bat roosting. If bat roosting behavior is determined to be adversely impacted by construction activities, construction must be avoided in the vicinity of bat roosts until either Class III Page 27 of 669
Executive Summary ES-10 Mid-Higuera Bypass Project Final SEIR bats are no longer roosting or they have been excluded from roosting. 3. If maternity roosts are detected, construction activities must be avoided within 100 ft (30 m) of an active maternity roost until the end of the maternity roosting season (end of September). No roost exclusion shall be conducted if maternity roosts are detected. 4. Readily visible exclusion zones shall be established in areas where roosts must be avoided. BR-mm 10 The design of the new Bianchi Lane Bridge shall incorporate bat friendly features and/or provide areas where manmade roosts can be easily attached during construction. If manmade roosts are to be attached to the bridge, this shall be accomplished prior to the conclusion of construction activities. BR Impact 6 Project construction will impact approximately 3.94 acres of riparian forest and riverine communities and result in the removal of approximately 128 native trees impacting the riparian habitat for wildlife. Short and medium term BR-mm 11 Prior to construction, the project proponent will retain a qualified biological monitor(s) to monitor construction and ensure compliance with Avoidance and Minimization Measures within the project environmental documents. Class III BR-mm 12 Before any activities begin on a project, a qualified biologist shall conduct a training session for all construction personnel. At a minimum, the training shall include a description of the important vegetation and special-status resources that occur in the project area, the specific measures that are being implemented to conserve them and the boundaries within which the project may be accomplished. Brochures, books, and briefings may be used in the training session, provided that a qualified person is on hand to answer any questions. BR-mm 13 During construction, work within the creek shall be conducted when the creek does not contain flowing or standing water, if feasible. If work activities must occur when water is present in the creek channel, the contractor shall dewater the creek prior to conducting the activities. BR-mm 14 Prior to any construction work beginning, including any vegetation clearing, sturdy high visibility fencing shall be installed to protect jurisdictional areas and sensitive resource areas adjacent to the work area. This fencing shall be placed so that unnecessary impacts to adjacent habitat are avoided. No construction work (including storage of materials) shall occur outside of the “Project Limits”. The required fencing shall remain in place during the entire construction period and maintained as needed by the contractor. BR-mm 15 During construction, the cleaning and refueling of equipment and vehicles will occur only within a designated staging area and as far from aquatic areas as feasible. At a minimum, all equipment and vehicles will be checked and maintained on a daily basis to ensure proper operation and avoid potential leaks or spills. BR-mm 16 During construction, the biological monitor(s) will ensure that the spread or introduction of invasive exotic plant species is avoided to the maximum extent possible. When practicable, invasive exotic plants in the project site will be removed and properly disposed. BR-mm 17 During construction, trash will be contained, removed from the work site, and disposed of regularly. Following construction, all trash and construction debris will be removed from work areas. All vegetation removed from the construction site shall be taken to a certified landfill to prevent the spread of invasive species. BR-mm 18 During construction, no pets will be allowed on the construction site. Page 28 of 669
Executive Summary ES-11 Mid-Higuera Bypass Project Final SEIR BR-mm 19 Prior to construction, a comprehensive Habitat Mitigation and Monitoring Plan (HMMP) shall be prepared that reflects the guidance of the WMP and includes the following guidelines: 1. Results in an improved pool to riffle ratio, reduction in invasive species, and increase of canopy cover provided by native species for Reach 10 compared to the 2002 assessment. 2. A 1:1 replacement ratio for temporary impacts to riverine and riparian vegetation communities. 3. A 2:1 replacement ratio for permanent impacts to riverine and riparian communities. 4. A replacement ratio for native trees and shrubs impacted by the project that will result in equal to or better habitat conditions within the project corridor as quickly as feasible. 5. Considers invasive species and debris removal in-lieu of a strict tree replacement ratio where appropriate 6. Allows for flexibility in species to be planted so that predominately single-trunk species such as black walnut, black cottonwood, and bay laurel can be substituted for willows, for example. 7. Takes advantage of the bypass channels and terraces between the bypass channels and the creek to replace the ruderal and nonnative annual grassland vegetation communities with riparian and upland ones, even in areas not directly impacted by the project construction. BR-mm 20 During construction, the project will make all reasonable efforts to limit the use of imported rock. Imported material should be obtained from a source that is known to be free of invasive plant species; or the material must consist of purchased clean material such as crushed aggregate, sorted rock, or similar. BR-Impact 7 Construction activities would result in impacts to nesting avian species Short and medium term BR-mm 21 To protect special-status avian species and those species protected by the MBTA, the District shall avoid vegetation clearing and earth disturbance during the typical nesting season (February 15 to September 1). If avoiding construction during this season is not feasible, a qualified biologist shall survey the area within one week prior to activity beginning on site. If nesting birds are located on or near the proposed project site, they shall be avoided until they have successfully fledged. A buffer zone of 50 feet will be placed around all non-sensitive, passerine bird species, and a 250-foot buffer will be implemented for raptor species, and all activity will remain outside of that buffer until the qualified biologist has determined that the young have fledged. Buffer reductions and/or work within non-disturbance buffer areas can be completed only with approval from relevant resource agencies. Class III CR Impact 1 Excavation of the project components, including, but not limited to the Flow Return, the Pinch Point, and the Bypass channels, have the potential to impact buried historical resources. Short-term CR-mm-1 Prior to construction, a detailed excavation and monitoring plan shall be prepared and implemented by a qualified historical archaeologist. The monitoring plan shall specify the following: 1. A description of preconstruction exploratory excavations at the Flow Return; 2. A description of how and where the monitoring will occur; 3. Description of monitoring intensity at different project locations; 4. A description of the resources anticipated to be discovered; 5. A description of the circumstances under which construction will be halted; 6. Description of the procedures to be followed in the event significant resources are found; 7. Personnel involved in monitoring activities; and 8. Arrangements for curation and a description of those materials that would qualify for curation. 9. Procedures to be implemented in the event there is an unanticipated historical or prehistoric discovered within the project area during construction to ensure compliance with State and local code. Class III HAZ Impact 1 During excavation of the project components construction personnel and the local environment may be exposed to hazardous materials that exist in the soils. Short-term Haz-mm-1 Prior to initiation of construction, the District shall submit to the City of San Luis Obispo Fire Department, a Construction Materials Management Plan (CMMP). The CMMP plan shall be implemented throughout construction. The CMMP shall at minimum present an overview of the procedures and protocols that will be utilized during the project to safely and appropriately recover, handle, characterize, store, transport, and dispose of any contaminated materials encountered during construction of the project. In the event that hazardous materials are encountered during excavation activities, the Class III Page 29 of 669
Executive Summary ES-12 Mid-Higuera Bypass Project Final SEIR contaminated soil shall be excavated to the extent necessary to safely construct the project. HWQ-Impact 1 The Flow Return would potentially concentrate polluted flood water and discharge it to the creek system with no treatment. Short-term HWQ-mm-1 Prior to construction, to minimize the potential for concentrating pollutants at the Flow Return where flood waters would re-enter San Luis Obispo Creek, this component shall be designed to maximize the potential for passive storm water treatment. Class III NS-Impact 1 Night-time or weekend construction would potentially significantly impact sensitive receptors in the project area. Short-term NS-mm 1 To reduce potential noise impacts, the following measures shall be implemented during construction: x Noise-generating construction activities shall be limited to between the hours of 7:00 a.m. and 7:00 p.m., Monday through Saturday. x Noise-generating construction activities shall be prohibited on Sundays and holidays. x Construction equipment shall be properly maintained and equipped with noise-reduction intakes and exhaust mufflers and engine shrouds, in accordance with manufacturers’ recommendations. x Equipment engine shrouds shall be closed during equipment operation. x Lay-down yards and semi-stationary equipment such as pumps or generators shall be located at the furthest practical distance from noise-sensitive land uses. Class III Page 30 of 669
Table of Contents
1
Mid-Higuera Bypass Project FSEIR
Table of Contents
Chapters
1.0 Introduction .................................................................................................................. 1-1
1.1 Project Background ................................................................................................... 1-1
1.2 Purpose of the EIR.................................................................................................... 1-1
1.3 Use of a Supplemental EIR ....................................................................................... 1-1
1.4 Scoping Process ....................................................................................................... 1-2
1.5 Draft Supplemental Environmental Impact Report..................................................... 1-2
1.5 EIR Contents ............................................................................................................ 1-2
1.6 Use of this Document ................................................................................................ 1-3
1.7 Project Sponsors and Contact Information ................................................................ 1-3
1.8 Relationship to Other Documents ............................................................................. 1-3
2.0 Project Description ....................................................................................................... 2-1
2.1 Project Summary ...................................................................................................... 2-1
2.2 Project Location ........................................................................................................ 2-1
2.3 Project Background ................................................................................................... 2-1
2.4 Project Objectives ..................................................................................................... 2-4
2.5 Project Components ................................................................................................. 2-4
2.6 Areas of Disturbance ................................................................................................ 2-6
2.7 Construction Techniques .......................................................................................... 2-6
2.8 Project Schedule ....................................................................................................... 2-7
2.9 Plans to Be Prepared ................................................................................................ 2-7
2.10 Permits and Authorizations .................................................................................... 2-8
3.0 Environmental Setting .................................................................................................. 3-1
3.1 CEQA Requirement .................................................................................................. 3-1
3.2 Plans and Policies..................................................................................................... 3-1
3.3 Cumulative Development Scenario ........................................................................... 3-3
4.0 Impact Assessment ...................................................................................................... 4-1
4.1 Aesthetic Resources ................................................................................................. 4-1
4.2 Air Quality/Greenhouse Gases................................................................................ 4-11
4.3 Biological Resources .............................................................................................. 4-21
4.4 Cultural Resources ................................................................................................. 4-43
4.5 Hazards and Hazardous Materials .......................................................................... 4-50
4.6 Hydrology / Water Quality ....................................................................................... 4-57
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Mid-Higuera Bypass Project FSEIR
4.7 Noise ...................................................................................................................... 4-64
5.0 Other CEQA-mandated Sections .................................................................................. 5-1
5.1 Section 15126 Topics ............................................................................................... 5-1
5.2 Appendix F: Energy Conservation ............................................................................. 5-2
6.0 Alternatives Analysis .................................................................................................... 6-1
6.1 Introduction ............................................................................................................... 6-1
6.2 Alternative Evaluation ............................................................................................... 6-1
6.3 Land Purchase/Business Relocation ......................................................................... 6-2
6.4 Marsh Street Bridge Replacement ............................................................................ 6-2
6.5 No Project Alternative ............................................................................................... 6-2
6.6 Environmentally Superior Alternative ........................................................................ 6-3
7.0 References and Preparers ........................................................................................... 7-1
Figures
2-1 Vicinity Map ....................................................................................................................2-2
2-2 Location Map ..................................................................................................................2-3
AR-1 Location and direction of Key Viewing Areas ...............................................................4-6
AR-2 KVA 1 - Existing view ..................................................................................................4-7
AR-3 KVA 1 – Photo-Simulation ...........................................................................................4-7
AR-4 KVA-2 - Existing view ..................................................................................................4-9
AR-5 KVA-2 - Photo-Simulation ............................................................................................4-9
Jurisdictional Areas Map – North ........................................................................................ 4-31
Jurisdictional Areas Map – South ....................................................................................... 4-32
CR-1 – Birds Eye View of San Luis Obispo ........................................................................ 4-44
HWQ-1 Floodplain Map ...................................................................................................... 4-59
NS-1 Sensitive Receptors Map ........................................................................................... 4-65
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Table of Contents
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Mid-Higuera Bypass Project FSEIR
Tables
2.1 Approximate Areas of Disturbance .................................................................................2-6
2.2 Anticipated Permits and Authorizations ...........................................................................2-8
AQ-1 Summary of Ambient Air Quality Standards & Attainment Designations .................... 4-12
AQ-2 Construction Emissions ............................................................................................. 4-16
AQ-3 Construction GHG Emissions .................................................................................... 4-20
BR-1 Impacts to Vegetation Communities .......................................................................... 4-29
BR-2 Tree Removal ............................................................................................................ 4-29
BR-3 Impacts to Jurisdictional Features (acres) ................................................................. 4-30
HWQ-1 San Luis Obispo Creek Peak Flows ....................................................................... 4-58
NS-1 Typical Construction Equipment Noise Levels ........................................................... 4-68
6.1 Alternatives Analysis .......................................................................................................6-4
Appendices
A. Notice of Preparation and Responses
B. Project Plans
C. Air Quality Background Information
D. Biological Resources Background Information
E. Response to Comments on the Draft Supplemental Impact Report
F. Mitigation Monitoring and Reporting Plan
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1.0 Introduction
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Mid-Higuera Bypass Project FSEIR
1.0 Introduction
1.1 Project Background
This Final Supplemental Environmental Impact Report (FSEIR) addresses the environmental
effects of the construction and operation of the Mid-Higuera Bypass Project (project). The
information presented here supplements the October 2003 San Luis Obispo Creek Watershed
Waterway Management Plan Final Programmatic Environmental Impact Report/Environmental
Impact Statement (EIR/EIS). The EIR/EIS is available for review at the County Public Works
Department. As described in the EIR/EIS:
“This Program level EIS/R addresses the potential environmental impacts of the proposed SLO
Creek Waterway Management Program that includes the Waterway Management Plan, the
Stream Maintenance and Management Plan and the Drainage Design Manual. The Program is
a combination of policies, programs and plans to address, in a regional or watershed-wide
manner, flooding and flood control along San Luis Obispo Creek and its tributaries.”
The project was specifically discussed in the EIR/EIS as one of five Capital Improvement
Projects; however, it was determined that subsequent environmental review would be required
at such time as project-specific data was available for review.
1.2 Purpose of the EIR
The goal of the California Environmental Quality Act (CEQA) is to:
1. Inform government decision makers and the public about the potential significant
environmental impacts of proposed activities; and
2. Identify ways that environmental impact(s) can be avoided or significantly reduced.
The purpose of an EIR is to provide State and local agencies and the general public with
detailed information on the potentially significant environmental effects which a proposed project
is likely to have, to list ways which the significant environmental effects may be minimized, and
indicate alternatives to the project.
This SEIR has been prepared in accordance with CEQA as amended, and the latest State
Guidelines for the Implementation of CEQA. The need for a SEIR is justified based upon the
review of project-specific design, the completion of project-specific technical reports, and the
completion of an Initial Study for the project (Refer to Appendix A).
1.3 Use of a Supplemental EIR
Once an EIR has been prepared for a project, a Lead Agency can generally rely on that EIR as
the CEQA “clearance” for that project. However, in some cases projects, or the circumstances
under which they occur, may change after the EIR is completed. More commonly, a period of
time passes between completion of the EIR and the implementation of the project. At this point,
a Lead Agency must determine whether the original EIR is still adequate for the project or
whether additional environmental review is required. The additional environmental review could
include an addendum or subsequent EIR.
The key findings for preparation of this SEIR are in section 15162(2) of the CEQA Guidelines in
that the level of detail now available in regards to the project description and the severity of
potential impacts constitutes a “substantial change” that requires revisions of the previous
EIR/EIS.
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1.0 Introduction
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Mid-Higuera Bypass Project FSEIR
1.4 Scoping Process
In accordance with the provisions of the State CEQA Guidelines, a Notice of Preparation (NOP)
for the project was distributed on February 19, 2016. The advertised comment period ended on
March 21, 2016. A total of 5 responses were received. These are included in Appendix A.
1.5 Draft Supplemental Environmental Impact Report
The Draft Environmental Impact Report (DSEIR) was released for public comment on
September 23, 2016 for a 45-day public review period. The review period closed on November
7, 2016. The District received four comment letters, three from public agencies, and one from a
member of the public. Appendix E of the Final EIR describes persons, organizations, and public
agencies commenting on the DSEIR; verbatim comments received through the EIR process;
and responses by the lead agency to comments received. The comments did not result in any
significant new information or substantial revisions to the DSEIR.
1.5 EIR Contents
The EIR is divided into the following major sections:
Executive Summary. Provides a brief summary of the project background, description, impacts
and mitigation measures, and alternatives.
Introduction. Provides the purpose of an EIR, as well as scope, content, and the use of the
document.
Project Description. Provides the general background of the project, objectives, a detailed
description of the project characteristics, and a listing of necessary permits and government
approvals.
Environmental Setting. Describes the surrounding land uses as well as plans and polices that
are relevant to the project. The section also includes a discussion of the projects consistency
with those plans and policies.
Environmental Impacts and Mitigation Measures. Discusses the environmental setting as it
relates to the various issue areas, regulatory settings, thresholds of significance, impact
assessment, project-specific impacts and mitigation measures, cumulative impacts, and
secondary impacts. Based on review of the EIR/EIS, the current project description, technical
reports, preparation of an Initial Study, and comments received on the NOP, the following
issues are covered in detail within the SEIR:
x Aesthetic Resources
x Air Quality / Greenhouse Gases
x Biological Resources
x Cultural Resources
x Hazards and Hazardous Materials
x Hydrology / Water Quality
x Noise
Other study areas typically fully analyzed in a EIR were not identified as having the likelihood of
significant effects, or are already addressed in the EIR/EIS. The reader should refer to the Initial
Study in Appendix A for additional information on that determination.
Other CEQA Mandated Topics. Identifies potential growth inducing impacts, irreversible
environmental changes and energy conservation.
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1.0 Introduction
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Mid-Higuera Bypass Project FSEIR
Alternatives. Summarizes the environmental advantages and disadvantages associated with the
project and alternatives. As required, the “No Project” alternative is included among the
alternatives considered. An “Environmentally Superior Alternative,” is identified.
1.6 Use of this Document
The following agencies may use this FSEIR in reviewing and issuing their respective permits
and authorizations (as applicable):
x United States Army Corps of Engineers (USACE)
x California Department of Fish and Wildlife (CDFW)
x Regional Water Quality Control Board (RWQCB)
x California Department of Transportation (Caltrans)
x San Luis Obispo County Air Pollution Control District (SLOAPCD)
x United States Fish and Wildlife Service (USFWS)
x National marine Fisheries Service (NMFS)
x City of San Luis Obispo
1.7 Project Sponsors and Contact Information
Key contact persons are as follows:
Lead Agency
San Luis Obispo County Flood Control and Water Conservation District
County Government Center, Room 200
San Luis Obispo, CA 93408
Mr. Keith Miller, Environmental Resource Specialist
Project Proponent
San Luis Obispo County Flood Control and Water Conservation District
County Government Center Room 200
San Luis Obispo, CA 93408
Ms. Jill Ogren, Project Manager
1.8 Relationship to Other Documents
This FSEIR supplements the 2003 EIR/EIS. The analysis contained here is intended to make
the changes and additions necessary to make the EIR/EIS adequate for the evaluation of the
currently proposed project. The EIR/EIS addressed a wide range of impacts to resources
throughout the San Luis Obispo Creek Watershed. The EIR/EIS was prepared to satisfy
National Environmental Policy Act (NEPA) requirements as well. This FSEIR focuses only on
those effects not considered in the EIR/EIS that would occur as a result of the specific project.
Further it does not include issues that were covered in the EIR/EIS that are primarily required by
NEPA – socioeconomics, for example. Copies of the EIR/EIS are available for review from the
San Luis Obispo County Department of Public Works.
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2.0 Project Description
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Mid-Higuera Bypass Project FSEIR
2.0 Project Description
2.1 Project Summary
The Mid-Higuera Bypass Project (project) is proposed to increase the flood control capacity of
San Luis Obispo Creek (creek) between Marsh Street and Madonna Road due to the following
concerns:
x there is currently less than 25-year storm capacity in this stretch of the creek;
x significant bank erosion exists in some locations;
x there is localized sediment accumulation, particularly at the Marsh Street Bridge;
x a poor pool-to-riffle ratio exists;
x substantial invasive species and exotic plants are present; and
x there is a lack of continuity and/or diversity in native riparian vegetation
The proposed project includes five components developed to directly address these issues,
including:
1. excavation of two new channels (South Street Bypass and the Bianchi Bypass) that
bypass the existing creek channel and be active during large storm events;
2. construction of channel terraces/benches and a flow return located adjacent to but
above the OHWM to increase capacity;
3. sediment removal at the Marsh Street Bridge;
4. replacement of the Bianchi Lane Bridge with a taller, wider bridge; and
5. riparian habitat enhancement, including the removal of invasive species, promotion of a
canopy of native species and willows overhanging pools, as well as the installation of
strategically located habitat features such as pool forming root wads, rock deflectors,
and vegetated rock slope protection.
The project was identified in both the City of San Luis Obispo’s (City) Waterway Management
Plan (WMP) and the associated EIR/EIS; however, in 2003 when the EIR/EIS was prepared the
project had only been developed to a conceptual level and could not be evaluated in the detail
required to satisfy CEQA requirements.
2.2 Project Location
The project is located within and adjacent to the creek between the Marsh Street Bridge
(upstream) and Madonna Road Bridge (downstream). It is bordered on the west by Highway
101 and on the east by Higuera Street. It is located completely within the City of San Luis
Obispo (refer to Figures 2-1 and 2-2).
2.3 Project Background
The creek has flooded on multiple occasions in the last 40 years between Marsh Street and
Madonna Road. The water level in the creek, immediately north of the Marsh Street Bridge,
rises above the top of the creek bank during periods of heavy rain. The creek water
subsequently flows into the adjacent City Streets, damaging public and private property.
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2.0 Project Description
2-2
Mid-Higuera Bypass Project FSEIR
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2.0 Project Description
2-3
Mid-Higuera Bypass Project FSEIR
Project area
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2.0 Project Description
2-4
Mid-Higuera Bypass Project FSEIR
The City, in conjunction with the County of San Luis Obispo Flood Control and Water
Conservation District Zone 9 (Zone 9), undertook and adopted the WMP after the 1995 flooding
of Higuera and surrounding streets. Several flood control projects were incorporated in the
WMP, including the original Mid-Higuera Bypass project.
In 2008, the Zone 9 Advisory Committee reduced the original project scope to include work that
would only occur on City of San Luis Obispo property because of significant property acquisition
costs. Subsequent engineering assessments confirmed that the reduced scope would still
reduce local flooding. Following the release of the study results, additional funding for
preliminary environmental studies was approved by the San Luis Obispo County Board of
Supervisors. The preliminary environmental studies showed no unusual site conditions that
would be a barrier to project completion.
At the same time Zone 9 began pursuing a small property swap with a property owner adjacent
to the City’s property near the Bianchi Lane Bridge. The property swap is required in order to
provide additional approach space for the project’s first bypass element to be constructed. This
element consists of the removal and replacement of the Bianchi Lane Bridge. Additional studies
were conducted between 2011 and 2015 including preliminary design and an alternatives
analysis. Following completion of the alternatives analysis, the Zone 9 Advisory Committee
selected and identified the preferred project.
2.4 Project Objectives
The primary objective of the project is to increase the flood-carrying capacity (up to a 25-year
storm in some locations) of San Luis Obispo Creek from Marsh Street to Madonna Road, while
enhancing and protecting water quality as well as special-status species habitat within the
project area. Secondarily, the project will provide preliminary grading for a conceptual bike path
alignment which could be constructed in the future along a portion of the project area.
2.5 Project Components
Each of the five project components are described in more detail below. Site plans are included
in Attachment B.
2.5.1 Bypass Channels
The project would include the construction of two bypass channels, the Bianchi Bypass and the
South Street Bypass. The bypass channels are proposed between the creek and Highway 101.
They have been designed to be active during larger storm events (i.e. they are designed to be
“above” the Ordinary High Water Mark [OHWM] of the creek), and to flow full during 25-year
storm events. Vegetated rock slope protection as well as root wads/flow deflectors would be
installed at both the upstream and downstream transition areas between the bypass channels
and the creek.
The South Street Bypass would be approximately 600 feet long, and 10 to 12 feet deep. The
channel bottom would be approximately 20 feet wide and the maximum channel slopes would
be 2.5 horizontal to 1 vertical (2.5:1). The Bianchi Bypass is approximately 800 feet long and 6
to 8 feet deep. The channel bottom would be approximately 20 feet wide and the maximum
channel slopes would be 2:1. In addition, an approximately 14-foot-wide bench would be
constructed at the western edge of the Bianchi Bypass to accommodate a future bike route. No
other bicycle related improvements are proposed.
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2.5.2 Benches and Related Grading
In addition to the bypass channels, the capacity and functionality of the creek channel would be
expanded through the construction of four benches, by laying back slopes at a “pinch point”,
and through construction of a “flow return”. Similar to the bypass channels, the four benches
proposed would be excavated above the creek OHWM and would reach approximately 20-30
feet wide. The maximum slopes above the benches would be excavated no steeper than 2.5:1.
Pinch Point
The pinch point is a narrow approximately 120-foot-long section of the channel at approximately
306 South Higuera Street, where the banks are nearly vertical and bordered on both sides by
structures. The channel would be graded in this area so that the slopes were no steeper than
2.5:1 and then stabilized with willow cuttings, or potentially a structural retaining wall. Grading
may require removal or modification of one or both structures at this location. Final design of
this component is still under development and subject to the approval of the private landowners.
Flow Return
Historically, the creek has backed up on the upstream side of the Marsh Street Bridge causing
flow to spill out of the creek and down Higuera Street. Grading of a flow return at the Mathews
Open Space parcel just downstream of the Marsh Street Bridge at 320 Higuera Street, is
proposed to allow escaped creek flows to be redirected from Higuera Street back to the creek
channel. The proposed grading will create two broad swales designed to convey flood flow
across the property to the creek. The final design is recommended to include a sidewalk
underdrain, shorter curb height, or a modified driveway design to capture flow from the gutter in
Higuera Street.
2.5.3 Marsh Street Sediment Removal
Significant sediment has accumulated on the upstream side of the Marsh Street Bridge and
within the three bridge barrels. Further, the upstream sediment has formed an island that is
blocking the largest center barrel. To address this issue, sediment will be removed upstream of
the bridge, within the bridge barrels, and downstream of the bridge. The sediment would be
removed to 1-foot above the creek water surface elevation at time of construction. This strategy
will preserve the existing low flow channel through the bridge. In addition, the western bank will
be sloped back to a 2.5:1 slope.
2.5.4 Bianchi Lane Bridge Replacement
The existing Bianchi Lane Bridge is an old bridge that was relocated to its current position many
years ago. It is relatively low and narrow, and as a result can only accommodate flows from a 6-
year storm event. The proposed new bridge will be a two-span bridge with a higher deck
elevation and will incorporate the start of the first bypass channel. The new bridge will provide
capacity for an approximately 23-year storm event. The new bridge installation will include
grading to accommodate the new road approaches on either side.
2.5.5 Riparian Enhancement
Riparian enhancements have been incorporated for each of the components described above.
Vegetated rock slope protection would be installed at the confluence of the creek channel and
the bypass channels. At these locations, root wads would also be installed to provide pools and
habitat complexity to the creek. At the Bianchi Bypass downstream transition area, rock flow
deflectors will be installed to create pools and hydrologic complexity.
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The project components have been designed to avoid and/or minimize impacts to the existing
creek channel to the extent feasible. Nevertheless, the project does include substantial grading
and tree removal. It is estimated that approximately 150 trees will be removed during
construction. These include native and nonnative species. Native trees removed will be
replaced with native species and planted in accordance with the City’s Drainage Design Manual,
which includes planting smaller crown trees (i.e. willow, buckeye, elderberry) closer to the
channel and large crown trees (oak, cottonwood, bay) on the upper banks, which will provide a
shaded, open channel while allowing for storm water capacity in the channel over the long-term.
In addition, invasive species encountered during construction will be removed. These species
include castor bean, cape ivy, giant reed (arundo), and Himalayan blackberry, for example. A
Habitat Mitigation and Monitoring Plan (HMMP) will be prepared as part of the subsequent
permitting process. The HMMP will include specific performance criteria and guide
implementation of mitigation during and after project construction.
2.6 Areas of Disturbance
Preliminary estimates of the areas of disturbance associated with each project component are
included in Table 2.1.
Table 2.1. Approximate Areas of Disturbance
Component Disturbance (acres) Cut/Fill (yds3)
Bypass Channels
South Bypass 2.20 11,500 / 500
Bianchi Bypass 2.67 17,000 / 500
Benches/Grading
4 Benches 1.74 3,900 / 150
Pinch Point 0.44 2,300 / 1,200
Flow Return 0.50 940 / 50
Marsh Street Sediment Removal 0.45 2,100 / 0
Bianchi Lane Bridge 0.37 3,700 / 0
Total 8.37 43,840
2.7 Construction Techniques
Access - Construction access will be from Bianchi Lane, 306 and 320 Higuera Street, and South
Street. In order to move equipment to the west side of the creek it may be necessary to
construct one or more temporary crossings within the dewatered channel. Temporary crossings
are anticipated to be at grade across the creek, with a gravel driving surface. A construction
staging area would be located on the western side of the Bianchi Lane Bridge adjacent to the
Madonna Construction site in a paved area. Construction haul routes would include Higuera
Street, with trucks using either the Marsh Street or Madonna Road Highway 101 ramps.
Construction traffic would temporarily use Higuera Street, Marsh Street, Bianchi Lane, South
Street, and Brook Street during the busiest construction periods.
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Equipment - Heavy equipment including excavators, dozers, backhoes, dump trucks, and
cranes would be required to construct the project. In addition, various flatbed trucks, pick-up
trucks, generators, pumps, and smaller scale equipment would be used during construction.
Soil Export - Approximately 41,500 cubic yards of material may need to be exported. It may be
possible to re-use a portion of that material onsite to provide a vegetated or earthen screen
between Highway 101 and development along Higuera Street. Any exported soil will be hauled
to a location that can legally accept the material.
Dewatering - San Luis Obispo Creek is a perennial creek and therefore it is anticipated that
substantial dewatering will be necessary to construct each component. A preliminary dewatering
plan is included in Appendix B. As shown in the plans, dewatering would be conducted in three
areas. The final dewatering plan will be prepared subsequently during the permitting process.
2.8 Project Schedule
As currently proposed, all components will be constructed as a single project in an
approximately 12-month period (grading and major construction activities would be completed in
6 months). Standard resource agency permit requirements will restrict work during the rainy
season, and therefore construction will generally occur between June 1 and October 15 within
the creek banks. Work outside the permit areas (outside the creek banks) may start earlier, or
finish later than the permit restricted periods. Restoration monitoring would continue for
approximately 3-5 years after construction, depending upon revegetation success and permit
requirements.
2.9 Plans to Be Prepared
Prior to the issuance of the permits, the regulatory agencies will require a number of project-
specific plans to address potential biological resources impacts and water quality/hydrology
impacts. This EIR assumes all of these plans, or their equivalents, will be required and are
therefore considered part of the project description rather than mitigation. These plans include,
for example:
Diversion and Dewatering Plan –This plan would describe the various structures and measures
that intercept the creek flows upstream of the project site, tr ansport it around or through the
work area, and discharge it downstream, while avoiding water quality and special-status species
impacts. These plans are prepared by engineers in consultation with biologists. These plans
include such components as predicted diversion flow rates, pump capacities, material to be
used, appropriate permits and approvals, contingency plans, removal and restoration plan, as
well as design accommodations for special-status species.
Stormwater Pollution Prevention Plan (SWPPP)/Sedimentation and Erosion Control Plan
(SECP) – A SWPPP, which is also called an “erosion, sedimentation, and pollution prevention
plan,” or similar is generally required to comply with EPA's or the State's storm water
construction general permit. SWPPPs include pollution, prevention team; site description;
summary of potential pollutant sources; description of control measures; schedules and
procedures.
Spill Prevention Control and Contingency Plan (SPCC) – This plan presents a coordinated and
integrated set of procedures, methods and equipment requirements to prevent oil and
hazardous substance discharges into or upon waters and environment of the State and United
States, and to contain such discharges if they should occur. It provides guidelines for
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responsible facility personnel for communication and required coordination with and notification
of the Federal, State and local response systems when a spill occurs.
Habitat Mitigation and Monitoring Plan (HMMP) – HMMPs are prepared for projects that require
habitat restoration to mitigate for impacts to biological resources and wetlands and are generally
prepared to comply with authorizations from the USACE, RWQCB, and the CDFW. The HMMP
will typically involve a detailed description of the environmental setting, the existing values of the
areas of disturbance, mitigation goals and strategies, an implementation plan, performance
criteria, maintenance and monitoring specifications and contingency plans. The HMMP also
describes site preparation activities, such as amending and redistributing topsoil, seeding and
planting, and provides recommendations for temporary irrigation systems and fencing, including
detailed construction drawings and specifications.
2.10 Permits and Authorizations
The project will require permits from, local, state and federal resource agencies. A list of permits
and/or authorizations that may be required is included in Table 2.2.
Table 2.2 Anticipated Permits and Authorizations
Agency Permit Required
City of San Luis Obispo Grading Permit
Central Coast Regional Water Quality
Control Board (RWQCB) Section 401 Water Quality Certification
California Department of Fish and Wildlife
(CDFW) Section 1602 Streambed Alteration Agreement
California Department of Transportation
(Caltrans) Encroachment Permit
Air Pollution Control District
Authority to Construct
NESHAP Permit
US Army Corps of Engineers (ACOE) Section 404 Clean Water Act Permit
National Marine Fisheries Service Biological Opinion
US Fish and Wildlife Service Biological Opinion
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3.0 Environmental Setting
The following section describes the plans and policies that are relevant to the proposed project
and evaluates qualitatively whether or not the project is consistent with those plans and policies.
In addition, this section describes the cumulative development scenario, which in turn provides
the basis for the cumulative impact discussions in Chapter 4.
3.1 CEQA Requirement
CEQA Guidelines section 15125 requires that an EIR discuss
“any inconsistencies between the proposed project and applicable general plans and regional
plans. Such regional plans include, but are not limited to, the applicable air quality attainment or
maintenance plan or State Implementation Plan, area-wide waste treatment and water quality
control plans, regional transportation plans, regional housing allocation plans, habitat
conservation plans, natural community conservation plans and regional land use plans…”
The following section describes the planning documents applicable to the project and describes
any potential inconsistencies, when applicable.
3.2 Plans and Policies
3.2.1 Waterway Management Program Documents
The Waterway Management Plan (WMP) program is a set of three documents, referred to as
Volumes I, II, and III. Volume I contains inventory information, a detailed hydrologic and
hydraulic analysis of the watershed and its main tributaries, as well as an identification of the
management problems and needs of the waterways. Alternatives for addressing flooding, bank
instability, and habitat protection and enhancement, are include and a preferred project is
presented. The Mid-Higuera Bypass project is specifically described as one component of the
“preferred project” in the WMP (project SLO I-3).
Volume II is referred to as the Stream Management and Maintenance Program (SMMP) for the
waterways of the San Luis Obispo Creek watershed. This document outlines the planning,
design, and permitting approach the City and County will utilize for routine stream maintenance,
such as vegetation management, bank repair, and sediment removal. Policies and Best
Management Practices for these activities are also described. Capital projects, such as the
proposed project are not discussed within Volume II, although the proposed maintenance
activities discussed in Volume II may be necessary within the project area over the long-term in
order to maintain both the flood capacity and environmental benefits of the project.
Volume III is a Drainage Design Manual (DDM), which contains revised policies for floodplain
and stream corridor management and provides new design flows for stream channels within the
City of San Luis Obispo. The DDM presents procedures for hydrologic and hydraulic analysis,
and guidelines and design criteria for the design of channel, storm drain systems, stormwater
detention facilities, bank repair and stream restoration, and erosion control. Important policy
revisions of the DDM are also summarized in this Volume (Waterway Management Plan). The
DDM objectives include:
1. Ensure that stormwater runoff in the San Luis Obispo (SLO) Creek watershed is
adequately controlled to reduce flood and environmental damage from new development
and redevelopment projects.
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2. Ensure that stormwater is carried through a system of waterways and conduits in such a
way that flood water surface elevations and corresponding flood damage does not
increase, damage is minimized at existing and future building sites, and existing flood
water surface elevations are reduced wherever feasible;
3. Ensure that the creeks, channels, and waterways remain relatively stable, or are
stabilized following development or redevelopment projects, and other projects such as
bank repair and hydraulic structures constructed near or along the waterways;
4. Preserve and protect natural biological resources along creeks and waterways, including
their functions and values, and ensure that they are restored and enhanced wherever
possible, and;
5. Protect and improve water quality.
The DDM was used by the project engineers to design the project. Proposed drainage and
stormwater control structures, habitat improvements, and revegetation strategies proposed are
taken directly from the DDM.
3.2.2 City of San Luis Obispo General Plan Land Use Element (LUE)
The primary zoning designations within the project area are Open Space, and General Retail,
although Services and Manufacturing (Madonna Construction parcel), and Park (Caltrans
facility) also exist. Much of the disturbance and construction activities would occur within the
City-owned parcels, which are zoned Open Space. The Land Use Elements “Creeks Wetlands,
and Flooding Policies” are described as follows in the LUE.
“San Luis Obispo's aquatic ecosystems consist of creeks, Laguna Lake, floodplains, marshes,
wetlands, serpentine seeps, and springs. These aquatic ecosystems provide habitat, recreation,
water purification, groundwater recharge, and soil production as well as natural flood protection
by reducing the force of floodwaters as they spread and decelerate over floodplains. Creeks,
which are the most obvious of these systems because they flow under and through the City,
provide wildlife habitat, backyard retreats, and viewing and hiking pleasures, in addition to
carrying storm water runoff. When some creeks overflow during major storms, they flood wide
areas beyond their channels. San Luis Obispo wants to avoid injury or substantial property
losses from flooding, while keeping or improving the creeks' natural character, scenic
appearance, recreational value, and fish and wildlife habitat.”
The proposed project is consistent with these general objectives as it is intended to reduce the
potential for flooding while improving fish and wildlife habitat. In addition, the project is cognizant
of the potential for a future bike trail in the area and has incorporated a potential future bike lane
into the grading design.
3.2.3 City of San Luis Obispo General Plan Conservation and Open Space Element
The goal of the Conservation and Open Space Element of the General Plan is to protect
resources such as air and water, wildlife habitat, scenic and agricultural lands, watershed and
historic features. A secondary goal is to accommodate passive recreation if it will “…not harm
the environment or interfere with agricultural operations.” Section 7 of the Conservation Element
discusses “Natural Communities” within the City limits. Policies in the element relevant to the
proposed project include:
7.3.1(A) Protect listed species. The City will identify the location, habitat and buffer needs of
species listed for protection. This information will be developed by qualified people early in the
planning and development review process.
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7.5.1 Protection of significant trees. Significant trees, as determined by the City Council upon
the recommendation of the Tree Committee, Planning or Architectural Review Committee, are
those making substantial contributions to natural habitat or to the urban landscape due to their
species, size, or rarity. Significant trees, particularly native species, shall be protected. Removal
of significant trees shall be subject to the criteria and mitigation requirements in Chapter 8.6.3.
Oak Woodland communities in the Greenbelt and in open space areas shall be protected.
7.5.5. Soil conservation and landform modification. Public and private development projects
shall be designed to prevent soil erosion, minimize landform modifications to avoid habitat
disturbance and conserve and reuse on-site soils.
7.7.6. Replace invasive, non-native vegetation with native vegetation. The City and private
development will protect and enhance habitat by removing invasive, non-native vegetation that
detracts from habitat values and by replanting it with native California plant species. The Natural
Resources Manger will prioritize projects and enlist the help of properly trained volunteers to
assist in non-native vegetation removal and replanting when appropriate.
The proposed project is generally consistent with these policies. The project does include
substantial landform modification, but this is proposed in part as a way to avoid directly
disturbing large portions of the creek channel.
3.2.4 City of San Luis Obispo Mid-Higuera Enhancement Plan
The Mid-Higuera Enhancement Plan (Plan) was prepared in 2001 and includes policies and
public investment strategies with a goal of making the Mid-Higuera area more attractive and
functional. The Plan boundaries extend from the corner of Marsh and Higuera Street south to
approximately the cemetery area near the intersection of Elks Lane and Higuera Street. The
plan area extends from Highway 101 on the west to approximately Walker and Beebee Street.
The Plan describes the existing flooding problems in the area and specifically describes the
possible causes. The flooding potential was noted as a significant constraint to future
enhancement/redevelopment in the area. The plan describes several mitigation strategies for
addressing the flooding potential, including the construction of terraces, bypass channels, and
replacement of the Marsh Street Bridge. The plan also recommends making better use of the
City-owned open spaces in the area, by constructing a bike trail, for example. No
inconsistencies between the Plan and the proposed project were identified.
3.3 Cumulative Development Scenario
CEQA Guidelines Section 15355 states that a cumulative impact:
“refers to two or more individual effects which, when considered together, are considerable or
which compound or increase other environmental impacts.”
An analysis of potential cumulative effects requires developing a list of probable future projects
that with impacts relevant to the proposed project, known as the “cumulative development
scenario.” A review of probable future projects in the region surrounding the Creek have been
identified below. They are either in proximity to the proposed project, and/or have similar
characteristics, and are therefore likely to contribute cumulatively to environmental impacts.
However, each environmental issue will evaluate potentially cumulative considerable impacts
based on scenarios appropriate for the section. For example, cumulative air quality effects may
be considered as they impact the entire air basin, while it is more appropriate to identify
cumulative noise impacts as they relate to sensitive receptors in the vicinity of the project
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corridor. Cumulative effects have been included within each resource issue area discussed in
this EIR (refer to Chapter 4). The proposed project extends through a relatively rural area.
SLO Creek Sediment Management Projects
The City routinely removes sediment that has accumulated in 5 to 10 different areas of SLO
Creek and its tributaries. Work is conducted in the dry season in areas with no standing or
flowing water at different locations every 1-5 years. Timing is dependent on funding, deposition
rates, and permitting timeframes. Work is conducted under the City’s Programmatic Streambed
Alteration Agreement and also requires permits from the Regional Water Quality Control Board
and the US Army Corps of Engineers. One of these projects is located just above the Marsh
Street Bridge, where grading as part of the proposed project is located. Work is conducted
consistent with the Waterway Management Plan.
Bob Jones Bike Path - Octagon Barn to the Ontario Road Staging Area
This project is an approximately 4.4-mile-long section of this Class I (separated from traffic)
bikeway roughly paralleling the San Luis Obispo Creek corridor between San Luis Obispo and
Avila Beach. An EIR for the project was certified in February 2015 (SCH#2010031121). Impacts
identified in that document included temporary and permanent impacts to biological resources,
including species and vegetation communities similar to those which would be impacted by the
proposed project, as well as impacts to visual resources; however, all impacts are considered
less-than-significant with mitigation.
Mid-Higuera Area Redevelopment Projects
Based on information from the City of San Luis Obispo Community Development Department,
there are a number of projects that are planned, permitted, or for which applications have been
submitted to the City. The list includes such projects as:
x 205 Higuera Street – Discussions of conversion of commercial space into office space
x 245 Higuera Street – Adaptive re-use commercial building into mixed use with two new
residential units
x 283 Higuera Street – Reconstruction of “The Sub” (existing building burned down)
x 311 Higuera Street – Use permit approved for Bar/Tavern within existing building
footprint
These projects are relatively small, urban redevelopment projects located on the eastside of
Higuera Street; therefore, they would not contribute cumulatively to any impacts to the San Luis
Obispo Creek corridor.
Redevelopment of the Caltrans facilities on either side of Madonna Road near the intersection
of Higuera Street to create a convention center and parking area has been proposed in concept;
however, any project at the Caltrans site would need to conform to more recent creek setback
policy, and therefore may ultimately have a beneficial impact to creek resources. The project is
not expected to contribute cumulatively to impacts to the creek corridor.
SLO Creek Arundo Removal Projects
The San Luis Obispo Land Conservancy has actively monitored/managed more than 400
arundo populations since 2005. Work is ongoing annually. Populations are treated with
herbicide, and removed mechanically or by hand. This project would have beneficial impacts to
the watershed as arundo is highly invasive.
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4.1 Aesthetic Resources
This section describes the existing visual setting along the project corridor and describes the
potential changes to that setting that could result from the project – primarily the vegetation
removal, but also any changes in landform related to the proposed grading. A visual
assessment was prepared for the project (SWCA 2016). This section summarizes that
document and includes the photo-simulations prepared. The visual assessment is available for
review from the County Public Works Department.
4.1.1 Existing Conditions
Mature vegetation is the dominant visual characteristic along the project corridor. The
vegetation corridor is approximately 150 feet wide, with the larger trees in the corridor more than
100 feet tall. In addition to the taller trees, which include eucalyptus and walnut, for example,
numerous lower growing trees and shrubs exist throughout the corridor.
The creek channel is the dominant landform within the corridor. Where development has not
encroached on the creek, primarily on the western side, there is a relatively flat bench. Other
natural landforms include a small, approximately 20-foot-tall knoll west of the proposed Bianchi
Bypass.
The built environment within the project area include the three bridges – Marsh Street, Bianchi
Lane, and Madonna Road – culverts, chainlink fencing, a number of sacrete walls within the
channel, as well as the commercial and industrial developments along the Mid-Higuera corridor.
The visual setting varies considerably depending upon which side of the corridor the viewer is
on. The vegetation and landforms are generally visible from the west (i.e. Highway 101), while
the commercial and residential developments are generally only visible from public roads to the
east of the project site, such as South Higuera Street. The visual assessment prepared for the
project determined that:
“The existing visual quality of the project site and its surroundings is moderately high because of
the intrinsic value of the creek and its mature vegetation, the generally low-intensity of the
surrounding development, and the availability of views to the surrounding hillsides and
mountains.”
Figure 11 of the Scenic Roadways and Vistas Map of the City of San Luis Obispo General Plan
Conservation and Open Space Element describes the project frontage along Highway 101 in
the area of Bianchi Lane as providing “Moderate Scenic Value”.
4.1.2 Regulatory Setting
The City’s General Plan documents including the Circulation Element, Conservation and Open
Space Element, Parks and Recreation Element, and Land Use Element include multiple policies
and programs that address the scenic value of the City’s open spaces, including the creek. A
sample of the policies is included below. A complete list of relevant policies is included in the
visual assessment.
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Circulation Element
15.1.2 Development Along Scenic Routes. The City will preserve and improve views of
important scenic resources form streets and roads. Development along scenic roadways should
not block views or detract from the quality of views.
15.1.3. Public Equipment and Facilities. The City and other agencies should be encouraged to
avoid cluttering scenic roadways with utility and circulation-related equipment and facilities.
Conservation and Open Space Element
9.1.1. Preserve natural and agricultural landscapes. C. The City’s non-emergency repair,
maintenance, and small construction projects in highly visible locations, such as hillsides and
downtown creeks, where scenic resources could be affected, shall be subject to at least “minor
or incidental” architectural review.
9.2.1. Views to and from public places, including scenic roadways. The City will preserve and
improve views of important scenic resources from public places, and encourage other agencies
with jurisdiction to do so. Public places include parks, plazas, the grounds of civic buildings,
streets and roads, and publicly accessible open space. In particular, the route segments shown
in Figure 11 are designated as scenic roadways.
Land Use Element
6.3. Open Space Policies. The City shall require that buildings, lighting, paving, use of vehicles,
and alterations to the landforms and native or cultural landscapes on open space lands are
minimized, so rural character and resources are maintained.
4.1.3 Significance Criteria
The significance of potential aesthetic resources impacts is based on thresholds identified within
Appendix G of the CEQA Guidelines. Appendix G provides the following thresholds for
determining significance with respect to aesthetic resources. Aesthetic resources impacts would
be considered significant if the proposed project would:
1. Have a substantial adverse effect on a scenic vista;
2. Substantially damage scenic resources, including, but not limited to, trees, rock
outcroppings, and historic buildings within a state scenic highway;
3. Substantially degrade the existing visual character or quality of the site and its
surroundings; or
4. Create a new source of substantial light or glare which would adversely affect day or
nighttime views in the area?
Because the project is not visible from any scenic highways, that threshold is not applicable.
Further, no new source of lighting or glare is proposed and therefore that threshold is not
applicable.
4.1.4 Impacts and Mitigation Measures
This section describes potential impacts and is organized based on the significance criteria
outlined above.
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4.1.4.1 Have a substantial adverse effect on a scenic vista
Scenic vistas identified in the area include primarily Cerro San Luis, and secondarily the South
Street Hills, and the Cuesta Ridge, including their intermediate slopes that contain pastures,
vegetated drainage features, open space, and rocky buttes.
When viewed from the east, the vegetation in the project corridor provides some context for
views of Cerro San Luis; however, the vegetation also limits the views of Cerro San Luis in
some locations. For example, the mature vegetation generally blocks views of Cerro San Luis
for those travelling northbound on Higuera Street near the Flow Return/Mathews Open Space
area.
When viewed from the east (i.e. from Highway 101 and the Madonna Inn Bicycle Path), the
creek does provide a vegetated foreground for views of the South Street Hills as well as Cuesta
Ridge. These vistas, while not as scenic as views toward Cerro San Luis, do contribute to the
visual quality of the area. Areas of extensive vegetation removal and earthwork along the creek
that would open-up views to adjacent development would somewhat degrade the foreground
context of hillside vistas to the east. However, the project’s effect on views to Cerro San Luis to
the west, and the Cuesta Ridge and South Street Hills to the east would be minimal as seen
from surrounding public areas. Impacts to scenic vistas would be less than significant. No
mitigation is required.
4.1.4.2 Degrade the existing visual character or quality of the site and its surroundings
The visual assessment concludes that the creek corridor provides scenic quality on its own, but
also acts as a buffer between Highway 101 and the Mid-Higuera developments between Marsh
Street and Madonna Road. The substantial tree removal proposed for this area, which includes
approximately 150 mature trees, along with their associated understory would be noticeable to
motorists on Highway 101, those on the Madonna Inn Bicycle Trail, and at the Bianchi open
space area. In some areas the vegetation removal would have a limited effect, but in others
where it provides screening of the built environment, it would result in a noticeable change. This
is especially true in the areas near the South Street Bypass, where “new” views of the back of
the commercial uses along South Higuera would be more noticeable along an approximately
1,400-foot-long section of Highway 101. The bypass channels would generally be “below grade”
and not noticeable, although they would represent a new built environment element and could
be visible from the open space areas, including the future extension of the Bob Jones Trail.
The project proposes to revegetate disturbed areas with a mix of native species. Taller, single
trunk species such as cottonwood, bay laurel, and walnut would be planted in lieu of willows, to
allow for additional flood control capacity within the channel. Similarly, the density of the
revegetation will be limited to allow for flood capacity along the bypass channel and benches to
be excavated. This scenario is described in the Vegetation Enhancement Plan in Appendix B.
The visual assessment concludes that:
“Upon reaching maturity (approximately 15-20 years following initial planting), proposed
overstory and canopy tree species mentioned in the Vegetation Enhancement Plan would help
re-create much of the overall vegetated character of the site. Planting within the rock-slope
protection would eventually visually screen the engineered appearance of those features.”
The degradation of the visual character over the short and medium term is considered a
potentially significant impact.
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AR Impact 1 The project would cause a noticeable change to the visual environment of the
site and its surroundings due to a loss of vegetative character, visibility of engineered channels
and slope protection, and increased visibility to the development along Higuera Street, South
Street and the Caltrans building north of Madonna Road as seen from Highway 101.
AR-mm-1 Prior to initiation of the project, the District shall ensure that revised grading and
site plans shall show the following:
1. All channel benches and bypass channels shall employ contour grading
design and construction techniques to reduce their engineered appearance.
All grade breaks shall be rounded and avoid angular slope-interface.
2. All top-of-slope hinge-points shall employ slope-rounding where doing so
would not adversely affect existing vegetation.
AR-mm-2 Prior to initiation of the project, the District shall ensure preparation and
implementation of a planting plan, which shall supplement the Vegetation
Enhancement Plan, be developed and signed by a licensed landscape architect
or restoration specialist, and include the following:
1. Visual screen planting between the easternmost extent of channel and bench
grading and the adjacent parcels east of the project, between Stations 13+50
and 17+00, and between Stations 22+50 and 27+00.
2. Screen planting shall be a mix of evergreen trees and shrubs placed in
natural-looking patterns.
3. Trees planted for screening along the fence shall be planted from primarily
24-inch box containers. Shrubs shall be planted from minimum 5-gallon
containers.
4. Screen planting shall include the appropriate number and density of plants to
achieve a minimum of 90 percent visual screening of the adjacent
development as seen from Highway 101 within five years.
5. Additional planting between the bypass channels and the Highway 101 right-
of-way, to the maximum extent possible.
6. Planting along Highway 101 shall be a mix of evergreen trees and shrubs
placed in natural-looking patterns.
7. Trees planted along Highway 101 shall be planted from primarily 24-inch box
containers. Shrubs shall be planted from minimum 5-gallon containers.
Residual Impacts. For the first approximately five years after construction the project would
cause a noticeable change in the visual character of the project corridor. Over time, the planting
proposed, along with the measures described above, would re-establish the visual character
and screening. They would reduce the impacts to a less than significant level. No additional
measures are required.
4.1.4.3 Cumulative Impacts
The project area plays a role in the City’s overall aesthetic quality and character of the area. Any
changes to the character if combined with other changes along the Mid-Higuera corridor, for
example, could potentially contribute to an emerging perception that San Luis Obispo is
undergoing a visual change toward increasing development. However, none of the other
projects described in the cumulative development scenario propose tree removal along the
creek corridor. Because the project’s impacts are mitigated to a less than significant level, and
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no other projects currently propose substantial changes in the vegetation along the corridor,
potential cumulative impacts are less than significant. No additional mitigation is required.
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Figure AR-1. Location and direction of Key Viewing Areas (KVA) and orientation of view.
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4.2 Air Quality/Greenhouse Gases
This section describes the existing air quality setting in San Luis Obispo County and the
potential short-term and long-term air quality impacts associated with development of the
proposed project. Information in this section summarizes the report Air Quality and Greenhouse
Gas Impact Assessment for the Proposed Mid-Higuera Bypass Project (Ambient, 2016). This
section also includes a discussion of greenhouse gas (GHG) emissions associated with project
implementation. Emissions calculations summaries from the air quality modelling performed for
this project are included in Appendix C. The entire report is available for review from the County
FCWCD.
4.2.1 Existing Conditions
The proposed project is located in San Luis Obispo County, which is part of the South Central
Coast Air Basin (SCCAB) and within the jurisdiction of the SLOAPCD. Air quality in the SCCAB
is influenced by a variety of factors, including climate, topography, local and regional
meteorology. Regional meteorology is largely dominated by a persistent high pressure area
which commonly resides over the eastern Pacific Ocean. Seasonal variations in the strength
and position of this pressure cell cause seasonal changes in the weather patterns of the area.
The Pacific High remains generally fixed several hundred miles offshore from May through
September, enhancing onshore winds and opposing offshore winds. During spring and early
summer, as the onshore breezes pass over the cool water of the ocean, fog and low clouds
often form in the marine air layer along the coast. Surface heating in the interior valleys
dissipates the marine layer as it moves inland.
4.2.1.1 Criteria Air Pollutants
For the protection of public health and welfare, the Clean Air Act (CAA) required that the United
States Environmental Protection Agency (U.S. EPA) establish National Ambient Air Quality
Standards (NAAQS) for various pollutants. These pollutants are referred to as "criteria"
pollutants because the U.S. EPA publishes criteria documents to justify the choice of standards.
These standards define the maximum amount of an air pollutant that can be present in ambient
air without harm to the public’s health. An ambient air quality standard is generally specified as
a concentration averaged over a specific time period, such as one hour, eight hours, 24 hours,
or one year. The different averaging times and concentrations are meant to protect against
different exposure effects. The CAA allows states to adopt additional or more health-protective
standards. Standards and the County’s attainment designations are shown in Table AQ-1.
4.2.1.2 Toxic Air Contaminants
Toxic air contaminants (TACs) are air pollutants that may cause or contribute to an increase in
mortality or serious illness, or which may pose a hazard to human health. TACs are usually
present in minute quantities in the ambient air, but due to their high toxicity, they may pose a
threat to public health even at very low concentrations. Because there is no threshold level
below which adverse health impacts are not expected to occur, TACs differ from criteria
pollutants for which acceptable levels of exposure can be determined and for which state and
federal governments have set ambient air quality standards. TACs, therefore, are not
considered “criteria pollutants” under either the Federal Clean Air Act (FCAA) or the California
Clean Air Act (CCAA).
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Table AQ-1
Summary of Ambient Air Quality Standards & Attainment Designations
Source: Ambient 2016
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4.2.1.3 Asbestos
Asbestos is the common name for a group of naturally-occurring fibrous silicate minerals that
can separate into thin but strong and durable fibers. Naturally-occurring asbestos, which was
identified as a TAC in 1986 by the ARB, is located in many parts of California and is commonly
associated with ultramafic rock. The project site is located near areas that are likely to contain
ultramafic rock; however, geologic surveys in the project area have not identified any asbestos-
containing materials (Padre 2015).
4.2.1.4 Greenhouse Gases
Various gases in the earth’s atmosphere, classified as atmospheric GHGs, play a critical role in
determining the earth’s surface temperature. Solar radiation enters the earth’s atmosphere from
space and a portion of the radiation is absorbed by the earth’s surface. The earth emits this
radiation back toward space, but the properties of the radiation change from high-frequency
solar radiation to lower-frequency infrared radiation. GHGs, which are transparent to solar
radiation, are effective in absorbing infrared radiation. As a result, this radiation that otherwise
would have escaped back into space is now retained, resulting in a warming of the atmosphere.
This phenomenon is known as the greenhouse effect. Among the prominent GHGs contributing
to the greenhouse effect are carbon dioxide, methane, nitrous oxide, hydrofluorocarbons,
perfluorocarbons, and sulfur hexafluoride.
On a global scale, GHG emissions are predominantly associated with activities related to
energy production; changes in land use, such as deforestation and land clearing; industrial
sources; agricultural activities; transportation; waste and wastewater generation; and
commercial and residential land uses. World-wide, energy production including the burning of
coal, natural gas, and oil for electricity and heat is the largest single source of global GHG
emissions.
In 2013, GHG emissions within California totaled 459 million metric tons (MMT) of CO2e. Within
California, the transportation sector is the largest contributor, accounting for approximately 37
percent of the total statewide GHG emissions. Emissions associated with industrial uses are the
second largest contributor, totaling roughly 23 percent. Electricity generation totaled roughly 20
percent.
4.2.2 Methodology
Short-term construction emissions associated with the proposed project were calculated using
the CalEEMod, version 2013.2.2, computer program. Construction of the proposed
improvements would occur during the non-rainy season (April 15 through October 15).
Construction activities are anticipated to occur over a single six-month period, though it’s
possible that some activities may occur during the following year. However, to ensure a
conservative analysis, all activities were assumed to occur during the initial six-month period of
construction. Up to approximately 41,400 cy of material was assumed to be exported and
approximately 2,400 cy of material may need to be imported. Off-road equipment anticipated to
be required during construction was derived from similar projects and default assumptions
contained in CalEEMod. Actual equipment required may vary. Modeling assumptions and output
files are included in Appendix C.
4.2.3 Regulatory Setting
Air quality within the SCCAB is regulated by several jurisdictions including the U.S. EPA, Air
Resources Board (ARB), and the SLOAPCD. Each of these jurisdictions develops rules,
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regulations, and policies to attain the goals or directives imposed upon them through legislation.
Because the state and local regulations generally equal or exceed Federal regulations, they are
described in this section.
4.2.3.1 California Air Resources Board
The ARB is the agency responsible for coordination and oversight of state and local air pollution
control programs in California and for implementing the CCAA. Other ARB duties include
monitoring air quality (in conjunction with air monitoring networks maintained by air pollution
control districts and air quality management districts, establishing California Ambient Air Quality
Standards (CAAQS), which in many cases are more stringent than the NAAQS, and setting
emissions standards for new motor vehicles.
4.2.3.2 California Clean Air Act
The CCAA requires that all air districts in the state endeavor to achieve and maintain CAAQS
for Ozone, CO, SO2, and NO2 by the earliest practical date. The CCAA specifies that districts
focus particular attention on reducing the emissions from transportation and area-wide emission
sources, and the act provides districts with authority to regulate indirect sources. Each district
plan is required to either (1) achieve a five percent annual reduction, averaged over consecutive
3-year periods, in district-wide emissions of each non-attainment pollutant or its precursors, or
(2) to provide for implementation of all feasible measures to reduce emissions. Any planning
effort for air quality attainment would thus need to consider both state and federal planning
requirements.
4.2.3.3 Assembly Bill 32 - California Global Warming Solutions Act of 2006
“AB 32” requires that statewide GHG emissions be reduced to 1990 levels by the year 2020.
The gases that are regulated by AB 32 include carbon dioxide, methane, nitrous oxide,
hydrofluorocarbons, perfluorocarbons, nitrogen trifluoride, and sulfur hexafluoride. The reduction
to 1990 levels will be accomplished through an enforceable statewide cap on GHG emissions
that will be phased in starting in 2012. To effectively implement the cap, AB 32 directs ARB to
develop and implement regulations to reduce statewide GHG emissions from stationary
sources. AB 32 specifies that regulations adopted in response to AB 1493 should be used to
address GHG emissions from vehicles. However, AB 32 also includes language stating that if
the AB 1493 regulations cannot be implemented, then ARB should develop new regulations to
control vehicle GHG emissions under the authorization of AB 32.
AB 32 requires that ARB adopt a quantified cap on GHG emissions representing 1990
emissions levels and disclose how it arrives at the cap, institute a schedule to meet the
emissions cap, and develop tracking, reporting, and enforcement mechanisms to ensure that
the state achieves reductions in GHG emissions necessary to meet the cap. AB 32 also
includes guidance to institute emissions reductions in an economically efficient manner and
conditions to ensure that businesses and consumers are not unfairly affected by the reductions.
4.2.3.4 County of San Luis Obispo Air Pollution Control District
The SLOAPCD is the agency primarily responsible for ensuring that NAAQS and CAAQS are
not exceeded and that air quality conditions, including GHGs within the region are maintained.
Responsibilities of the SLOAPCD include, but are not limited to, preparing plans for the
attainment of ambient air quality standards, adopting and enforcing rules and regulations
concerning sources of air pollution, issuing permits for stationary sources of air pollution,
inspecting stationary sources of air pollution and responding to citizen complaints, monitoring
ambient air quality and meteorological conditions, and implementing programs and regulations
required by the FCAA and the CCAA.
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4.2.4 Significance Criteria
The significance of potential air quality impacts is based on thresholds identified within Appendix
G of the CEQA Guidelines and standards established within the SLOAPCD CEQA Air Quality
Handbook. Appendix G of the CEQA Guidelines provides the following thresholds for
determining significance with respect to air quality and GHGs. Air quality and GHG impacts
would be considered significant if the proposed project would:
1. Conflict with or obstruct implementation of the applicable clean air plan;
2. Violate any air quality standard or contribute substantially to an existing or projected air
quality violation;
3. Result in cumulatively considerable net increase of any criteria pollutant for which the
project region is non-attainment under an applicable federal or state ambient air quality
standard (including releasing emissions which exceed quantitative thresholds for ozone
precursors);
4. Expose sensitive receptors to substantial pollutant concentrations;
5. Create objectionable odors affecting a substantial number of people;
6. Generate greenhouse gas emissions, either directly or indirectly, that may have a
significant impact on the environment; or
7. The project conflict with an applicable plan, policy, or regulation adopted for the purpose
of reducing the emissions of greenhouse gases?
To assist in the evaluation of air quality impacts, the SLOAPCD has developed recommended
significance thresholds, which are contained in the SLOAPCD’s CEQA Air Quality Handbook
(2012). The threshold criteria established by the SLOAPCD to determine the significance and
appropriate mitigation level for a project’s short-term construction emissions are presented in
Table AQ-2.
4.2.5 Impacts and Mitigation Measures
This section describes impacts related to construction of the project and is organized based on
the significance criteria outlined above and the data provided in the tables below.
4.2.5.1 Conflict with or obstruct implementation of the applicable clean air plan
According to the SLOAPCD’s CEQA Air Quality Handbook (2012), a consistency analysis with
the Clean Air Plan is required for a program-level environmental review, and may be necessary
for a larger project-level environmental review, depending on the project being considered.
Project-level environmental reviews which may require consistency analysis with the Clean Air
Plan include: large residential developments and large commercial/industrial developments. For
such projects, evaluation of consistency is based on a comparison of the proposed project with
the land use and transportation control measures and strategies outlined in the Clean Air Plan.
If the project is consistent with these measures, the project is considered consistent with the
Clean Air Plan.
The proposed project is consistent with current zoning and would not result in increased
population or employment. In addition, the proposed project would not result in the installation of
any major stationary sources of emissions. For this reason, the proposed project would not
conflict with SLOAPCD’s Clean Air Plan. This impact is considered less than significant. No
mitigation is required.
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4.2.5.2 Violate any air quality standard or contribute substantially to an existing or
projected air quality violation
Estimated daily and quarterly emissions are summarized and compared to SLOAPCD’s
significance thresholds in Table AQ-2. Maximum daily construction-generated emissions of
ROG+NOX and exhaust PM10 could potentially exceed SLOAPCD significance thresholds.
Quarterly thresholds would not be exceeded. In addition, fugitive dust generated during
construction may result in localized pollutant concentrations that could result in increased
nuisance concerns to nearby residents.
Table AQ-2
Construction Emissions
Criteria Project
Emissions
Significance
Threshold
Threshold
Exceeded?
Daily Emissions (ROG+NOX) 220 lbs 137 lbs Yes
Daily Emissions (DPM) 10 lbs 7 lbs Yes
Quarterly Emissions (ROG+NOX) 1.9 tons 2.5 tons No
Quarterly Emissions (DPM) 0.09 tons 0.13 tons No
Quarterly Emissions (Fugitive PM) 0.3 tons 2.5 tons No
AQ Impact 1 Project construction activities would result in emissions levels that exceed
SLOAPCD thresholds.
AQ-mm 1 A Construction Activity Management Plan (CAMP) shall be prepared for the
proposed project. The CAMP shall be submitted to the SLOAPCD for review and approval prior
to the start of construction. The CAMP shall include, at a minimum, the following elements:
1. Identification of the project construction schedules. To the extent possible, construction
activities should be phased to minimize cumulative increases of daily emissions from
multiple activities.
2. Identification of schedules for truck hauling activities and associated haul routes. Haul
routes and schedules that would have the least impact to nearby sensitive receptors
shall be selected.
Construction activities and haul truck trips should be scheduled during non-peak hours
(as determined by the Public Works Director) to reduce peak hour emissions.
3. Identification of construction-equipment permitting requirements. Portable equipment, 50
horsepower (hp) or greater, used during construction activities may require California
statewide portable equipment registration (issued by the California Air Resources Board)
or a SLOAPCD permit. Examples of such equipment may include, but are not limited to,
standby generators, material processing equipment (e.g., crushers, conveyors, portable
batch plants, tub grinders, trammel screens).
4. Identification of a designated person or persons responsible for implementation of the
CAMP and emissions monitoring and compliance. The designated individual(s) shall be
responsible for monitoring of fugitive dust emissions and the
implementation/enhancement of measures, as necessary, to minimize dust complaints,
reduce visible emissions below the SLOAPCD’s limit of 20% opacity for greater than 3
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minutes in any 60-minute period. Their duties shall include holidays and weekend
periods when work may not be in progress. The name and telephone number of such
persons shall be provided to the SLOAPCD Compliance Division prior to the start of any
grading, earthwork or demolition.
5. Tabulation of on-road and off-road construction equipment. Emissions shall be quantified
in accordance with SLOAPCD-recommended methodologies based on project-specific
construction requirements (e.g., construction schedules, construction vehicle trips, and
off-road equipment fleet to be used during project construction.
6. Identification of fugitive dust and mobile-source emission control measures to be
implemented sufficient to demonstrate compliance with SLOAPCD’s CEQA thresholds of
significance and to minimize nuisance impacts at nearby sensitive receptors.
Residual Impact. This mitigation measure would reduce impacts to less than significant. No
additional mitigation is required.
4.2.5.3 Expose sensitive receptors to substantial pollutant concentrations
The project site is located within and adjacent to San Luis Obispo Creek between the Marsh
Street Bridge and Madonna Road Bridge. The proposed construction area is bordered on the
west by Highway 101 and on the east by Higuera Street and existing development. The
adjacent existing development consists largely of a mix of light industrial, commercial, and
residential land uses. The nearest residential dwellings are located adjacent to and east of San
Luis Obispo Creek along Brook Street, south of South Street. St. Luke Missionary Baptist
Church and Eto Park are also located along Brook Street, south of South Street. In addition,
Mathews Trailer Lodge is located adjacent to and east of San Luis Obispo Creek, south of
Bianchi Lane.
Demolition activities can have potential negative air quality impacts, including issues
surrounding proper handling, demolition, and disposal of asbestos containing material (ACM).
Asbestos containing materials could be encountered during demolition of existing structures,
particularly older structures constructed prior to 1970. Asbestos can also be found in various
building products, including (but not limited to) utility pipes/pipelines (transite pipes or insulation
on pipes). If a project will involve the disturbance or potential disturbance of ACM, various
regulatory requirements may apply, including the requirements stipulated in the National
Emission Standard for Hazardous Air Pollutants (40CFR61, Subpart M - Asbestos NESHAP).
The project site will require demolition of Bianchi Lane Bridge. As a result, demolition activities
have the potential to result in the disturbance of ACM.
Construction of the proposed project may result in the generation of fugitive dust. Fugitive dust
emissions would be primarily associated with earth-moving, material handling and demolition
activities, as well as vehicle travel on unpaved and paved surfaces. Onsite off-road equipment
and trucks would also result in short-term emissions of diesel-exhaust PM (DPM). Construction-
generated emissions of PM could result in localized concentrations of PM that could result in
increased nuisance impacts to nearby land uses and receptors.
Demolition of structures coated with lead based paint can have potential negative air quality
impacts and may adversely affect the health of nearby individuals. Improper demolition can
result in the release of lead containing particles from the site. Sandblasting or removal of paint
by heating with a heat gun can result in significant emissions of lead.
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AQ Impact 2 The project could expose sensitive receptors to pollutants such as lead and
fugitive dust.
AQ-mm 2 The following measures shall be implemented to reduce potential expose of
sensitive receptors to substantial pollutant concentrations. These measures shall also be
included in the CAMP to be prepared for this project
1. Demolition of onsite structures shall comply with the National Emission Standards for
Hazardous Air Emissions (NESHAP) requirements (NESHAP, 40 CFR, Part 61, Subpart
M) for the demolition of existing structures. The SLOAPCD is delegated authority by the
Environmental Protection Agency (EPA) to implement the Federal Asbestos NESHAP.
Prior to demolition of onsite structures, the SLOAPCD shall be notified, per NESHAP
requirements.
2. If during demolition of Bianchi Lane Bridge, paint is separated from the construction
materials (e.g. chemically or physically), the paint waste will be evaluated independently
from the building material by a qualified hazardous materials inspector to determine its
proper management. All hazardous materials shall be handled and disposed in
accordance with local, state and federal regulations.
3. According to the Department of Toxic Substances Control (DTSC), if paint is not
removed from the building material during demolition (and is not chipping or peeling), the
material can be disposed of as construction debris (a non-hazardous waste). The landfill
operator will be contacted prior to disposal of building material debris to determine any
specific requirements the landfill may have regarding the disposal of lead-based paint
materials. The disposal of demolition debris shall comply with any such requirements.
4. On-road diesel vehicles shall comply with Section 2485 of Title 13 of the California Code
of Regulations. In general, the regulation specifies that drivers of said vehicles:
x Shall not idle the vehicle’s primary diesel engine for greater than 5 minutes at
any location, except as noted in Subsection (d) of the regulation; and,
x Shall not operate a diesel-fueled auxiliary power system to power a heater, air
conditioner, or any ancillary equipment on that vehicle during sleeping or resting
in a sleeper berth for greater than 5.0 minutes at any location when within 1,000
feet of a restricted area, except as noted in Subsection (d) of the regulation.
x Off-road diesel equipment shall comply with the 5-minute idling restriction
identified in Section 2449(d)(2) of the California Air Resources Board’s In-Use
off-Road Diesel regulation.
x Signs must be posted in the designated queuing areas and job sites to remind
drivers and operators of the state’s 5-minute idling limit.
x Construction truck trips shall be scheduled, to the extent feasible, to occur during
non-peak hours.
x The burning of vegetative material shall be prohibited.
5. Should hydrocarbon contaminated soil be encountered during construction activities, the
SLOAPCD shall be notified as soon as possible and no later than 48 hours after affected
material is discovered to determine if a SLOAPCD Permit will be required. In addition,
the following measures shall be implemented immediately after contaminated soil is
discovered:
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x Covers on storage piles shall be maintained in place at all times in areas not
actively involved in soil addition or removal;
x Contaminated soil shall be covered with at least six inches of packed
uncontaminated soil or other TPH –non-permeable barrier such as plastic tarp.
No headspace shall be allowed where vapors could accumulate;
x Covered piles shall be designed in such a way to eliminate erosion due to wind
or water. No openings in the covers are permitted;
x The air quality impacts from the excavation and haul trips associated with
removing the contaminated soil must be evaluated and mitigated if total
emissions exceed the SLOAPCD’s construction phase thresholds;
x During soil excavation, odors shall not be evident to such a degree as to cause a
public nuisance; and,
x Clean soil must be segregated from contaminated soil.
Residual Impact. This measure, which address TACs and similar pollutants would reduce
impacts to a less than significant level. No additional mitigation is required.
4.2.5.4 Create objectionable odors affecting a substantial number of people
The proposed project would not result in the installation of any equipment or processes that
would result in odorous emissions. However, construction of the proposed project would involve
the use of a variety of gasoline or diesel-powered equipment that would emit exhaust fumes.
Exhaust fumes, particularly diesel exhaust, may be considered objectionable by some people.
In addition, pavement coatings and architectural coatings used during project construction
would also emit temporary odors. However, construction-generated emissions would occur
intermittently throughout the workday and would dissipate rapidly with increasing distance from
the source. As a result, short-term construction activities would not expose a substantial number
of people to frequent odorous emissions. For these reasons, potential exposure of sensitive
receptors to odorous emissions would be considered less than significant. No mitigation is
required.
4.2.5.5 Generate greenhouse gas emissions, either directly or indirectly, that may have a
significant impact on the environment
Estimated GHG emissions attributable to future development would be primarily associated with
increases of CO2 from mobile sources. To a lesser extent, other GHG pollutants, such as CH4
and N2O, would also be generated. Estimated increases in GHG emissions associated with
construction of the proposed project are summarized in Table AQ-2. Assuming that all
construction activities were to occur within a single year, annual emissions of GHGs would total
approximately 430.4 MTCO2e. There would also be a small amount of GHG emissions from
waste generated during construction; however, this amount is speculative. Short-term
construction-generated emissions would not exceed 1,150 MTCO2e/year. The proposed project
is consistent with current zoning and would not result in increased population or employment,
nor would the project result in the installation of any major stationary sources of emissions. As a
result, the proposed project is not anticipated to result in long-term increases of GHGs. Impacts
would be less than significant. No mitigation is required.
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Table AQ-3
Construction GHG Emissions
Construction Activity GHG Emissions
(MTCO2e/Year)
Bianchi Lane Bridge Demolition/Removal 27.3
Bianchi Lane Bridge Construction 18.5
Bianchi Lane Grading 4.6
Bianchi Lane Paving 3.0
Excavation of Two New By-Pass Channels 300.4
Construction of Terraces and Benches 63.4
Sediment Removal at Marsh Street Bridge 13.2
Construction Phase Total 430.4
SLOAPCD Significance Threshold 1,150
Exceeds Threshold? No
4.2.5.6 Would the project conflict with an applicable plan, policy, or regulation adopted
for the purpose of reducing the emissions of greenhouse gases?
The proposed project is consistent with current zoning and would not result in increased
population or employment, and is not anticipated to result in long-term increases of GHGs. In
addition, the preliminary grading for the future bikeway would help to support the GHG-reduction
measures identified in the City’s CAP, including measures to improve bicycle access and efforts
to achieve a 20 percent bicycle mode share by 2020. The proposed project would also include
the planting of approximately 240 new trees. Over the life of the project, these trees would result
in an increase in carbon sequestration of roughly 170 MTCO2e. For these reasons, this impact
would be considered less than significant.
4.2.6 Cumulative Impacts
The County is currently designated non-attainment for the state ambient air quality standards
(AAQS) for ozone and PM10. Short-term construction-generated emissions of ozone precursor
pollutants (e.g., ROG and NOX) and exhaust PM10 could potentially exceed SLOAPCD
significance thresholds. In addition, fugitive dust generated during construction may result in
localized pollutant concentrations that could result in increased nuisance concerns to nearby
residents. Uncontrolled increases of these construction-generated pollutants could contribute,
on a cumulative basis, to existing non-attainment conditions. Implement of AQ-mm-1 and AQ-
mm-2 would reduce project-specific impacts and the project’s contribution to cumulative impacts
to a less than significant level. Further, all emissions are short-term, and therefore the project
would contribute no emissions once construction is completed. No additional mitigation is
required.
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4.3 Biological Resources
This section evaluates potential impacts to biological resources within the project area. The
analysis considers special-status plant, animal, and vegetation communities as well as impacts
to areas that are located within the jurisdiction of state and federal resource agencies. Potential
short-term and long-term impacts to biological resources are described. For those instances
where potential impacts to sensitive biological resources may occur, mitigation measures and
best management practices have been developed. The San Luis Obispo Creek watershed and
creek system was described in depth in the Waterway Management Plan (WMP) and
Environmental Impact Report/Statement (EIR/EIS), and readers should refer to those
documents for additional setting information. This section focuses specifically on the project
corridor.
4.3.1 Methodology
This section was prepared based on a number of literature reviews and field surveys performed
during preparation of the WMP and subsequent project-specific assessments. The WMP,
Volume 1, Appendix B included a biological resources inventory of each reach of San Luis
Obispo Creek. A project-specific habitat assessment was prepared by the County Public Works
Department in 2010. Once the 30% plans were completed in 2015, an updated literature review
and biological reconnaissance surveys were completed. In addition, recently completed
environmental documents prepared for the Los Osos Valley Road/Highway 101 interchange
project, which is approximately 1.5 miles downstream of the project, were reviewed.
This baseline environmental data was reviewed in the context of the proposed project areas of
disturbance and proposed enhancement activities to identify short and long-term impacts that
could result from the project. Project-proposed mitigation, which is consistent with the best
management practices and other WMP guidance, was then reviewed to determine if it reduced
impacts to a less than significant level. In cases where it did not, additional mitigation is
recommended.
4.3.2 Existing Conditions
The project corridor follows the San Luis Obispo Creek corridor between Marsh Street and
Madonna Road. The corridor has been impacted historically through the construction of
Highway 101, and by the encroachment of commercial and residential land uses along the Mid-
Higuera commercial strip. In some places, this encroachment is literally beyond the top of the
creek bank. In addition, creek bank stabilization in the form of sacrete walls and concrete, are
located along the banks of the creek. The Bianchi Lane Bridge and the Marsh Street Bridge
cross the creek within the project area. A number of culverts discharge into the creek through
the project corridor.
Based on the Natural Resources Conservation Service maps, soils within the project corridor
include Salinas silty clay loam, formed in alluvium weathered from sedimentary rocks. Uplands
in the northwestern portion of the study area are mapped as Los Osos-Diablo complex, which
formed in residual material weathered from sandstone or shale. No serpentine-derived soils are
mapped within the project corridor.
4.3.2.1 WMP Reach 10 Biological Resources Inventory (2002)
The project corridor includes the downstream 75% of what is considered Reach 10 in the WMP.
Reach 10 is described in the WMP as follows:
x land use within this reach is largely urban, with both commercial and residential
development encroaching on the creek corridor;
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x the riparian corridor ranges in width from 15-35 meters, with mixed willows and
eucalyptus dominating the canopy vegetation;
x understory species consist largely of exotics, such as Arundo, castor bean, and cape ivy;
x approximately 92% of Reach 10 is classified as flatwater habitat, with pools and riffles
composing nearly 5% and 3% of the remaining instream habitat areas, respectively;
x the pool frequency ratio was 6.5/km, which represents one of the lowest frequencies
noted within the watershed; and,
x concrete rip-rap and sack revetments, and gabions are abundant along the streambank
at several locations, apparently reflecting attempts to stabilize actively eroding slopes
adjacent to residential and commercial developments.
The inventory identified 13 special-status botanical species that could occur in the watershed –
noting that most are associated with serpentine-derived soils. None of these species were
observed within the reach during spring surveys performed for the WMP. This may be in large
part due to the apparent lack of serpentine-derived soils within the project corridor.
The inventory also identified 13 special-status wildlife species with the potential to occur within
the watershed. Of these, three either have been observed or have the potential to be observed
within Reach 10 - the south-central California coast steelhead, the monarch butterfly, and pallid
bat.
4.3.2.2 Habitat Assessment (2010)
The habitat assessment prepared in 2010 (County of San Luis Obispo 2010) included a review
of CNDDB records, a species list provided by the USFWS and two field surveys, conducted in
May 2010. The surveys identified three primary vegetation communities within the project area,
Riparian Forest, Riverine, and Non-native Annual Grassland. The assessment noted the
dominance of nonnative, invasive species within the understory of the riparian forest habitat.
Based on a list of CNDDB records within the USGS San Luis Obispo quadrangle, the
assessment considered 26 special–status plant species, including all 13 considered in the
original WMP inventory. No special-status plant species were observed during the field surveys.
The habitat assessment confirmed the lack of serpentine soils and outcrops within the project
area.
Thirteen special-status wildlife species were considered in the assessment. Those that have
been observed in the past, and with the potential to occur within the project area include
monarch butterfly, south-central California coast steelhead, pallid bat, Yuma myotis, Cooper’s
hawk, and yellow warbler, as well as numerous species protected by the Migratory Bird Treaty
Act (MBTA) that may nest in the riparian corridor. The assessment concluded that the riparian
habitat along the project corridor was generally of low quality due to a number of factors,
including:
1. much of the native plant cover, especially the understory, has been replaced by non-
native species, many of which are invasive;
2. urban uses occur along the majority of the east bank;
3. non-engineered concrete rubble as well as engineered slope protection exists in many
places, reducing the area of natural stream bank, and failed structures have resulted in
rubble littering the streambed;
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4. there is considerable unauthorized human use of the area, including encampments, with
associated refuse;
5. a minimal amount of adjacent natural upland habitat exists; and
6. Highway 101, just to the west, acts as a barrier to wildlife movement.
4.3.2.3 Vegetation Communities
Biological resources reconnaissance surveys performed in March 2016 confirmed the
conclusions of the 2010 habitat assessment. There are three primary vegetation communities
within the project corridor. They are described below. A complete list of species identified during
the 2010 and 2016 surveys is included in Appendix D. No off-channel or adjacent wetlands were
identified within the project corridor.
Riparian Forest
Riparian forest occurs through much of the project area, and consists of moderate to dense
closed-canopy broadleaf vegetation that closely follows streambank contours. A mixture of
native and non-native plant species characterize the area. Common overstory species include:
arroyo willow (Salix lasiolepis), western sycamore (Platanus racemosa), Fremont cottonwood
(Populus fremontii ssp. fremontii), white alder (Alnus rhombifolia), and non-native blue gum
eucalyptus (Eucalyptus globulus). Understory species include the non-native invasive species
such as elmleaf blackberry (Rubus ulmifolius), cape ivy (Delairea odorata), greater periwinkle
(Vinca major), and garden nasturtium (Tropaeolum majus), as well as native California
blackberry (Rubus ursinus) and mugwort (Artemisia douglasiana). A large stand of mature blue
gum trees occurs at the south end of the project area along the east bank. Mature blue gum
trees are also present on the west side of the Bianchi Lane bridge.
Riverine
Riverine habitat is found within the actively flowing channel, roughly corresponding with the
creek’s ordinary high water mark (OHWM). Seasonally, this habitat type supports emergent
hydrophytes such as watercress (Nasturtium officinale), giant horsetail (Equisetum telmateia
var. braunii) and spearmint (Mentha spicata). Filamentous green algae were found attached to
cobbles and other streambed substrate, especially where sufficient sunlight reaches the water.
Non-native Grassland
Non-native grassland occurs in the proposed Bianchi and South Street bypasses. The dominant
plant species include non-native grasses such as slender wild oat (Avena barbata), Spanish
brome (Bromus madritensis), Harding grass (Phalaris aquatica), Mediterranean barley
(Hordeum marinum ssp. gussoneanum), and mostly non-native annual and perennial herbs,
including Italian thistle (Carduus pycnocephalus), milk thistle (Silybum marianum), and rose
clover (Trifolium hirtum). This community is sparsely vegetated with nonnative forbs, and shrub
species such as coyote brush (Baccharis pilularis). These areas are mowed regularly by the
City of San Luis Obispo to reduce fire risk and control unauthorized use of the open space
properties.
Special-status Plants
In March 2016 a CNNDB search of all plant records within the San Luis Obispo USGS quad
was repeated. The nearest special-status plant occurrences exist 0.25 mile to the southwest of
the project site in the undeveloped South Hills, and approximately 0.5 mile to the west in the
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Laguna Lake area, both of which are associated with serpentine-derived soils. Please refer to
Appendix D for a list of special-status plant species considered in this EIR.
On March 25, 2016 an additional biological resources reconnaissance survey of the project area
was completed. Jurisdictional areas were confirmed and the site was surveyed again for the
presence of special-status botanical and wildlife resources. While the timing of the survey did
not coincide with the blooming periods of all species identified in the CNDDB search, the lack of
serpentine-derived soils, the high level of disturbance, and extensive non-native grassland and
invasive species was confirmed. Consistent with previous survey efforts, no special-status plant
species were observed during the 2016 survey.
4.3.2.4 Special-status Wildlife
In March 2016 a CNDDB search of all special-status wildlife records within the San Luis Obispo
USGS quad was repeated. Please refer to Appendix D for a list of special-status wildlife
considered. Based on the literature review and field surveys, wildlife known to, or with the
potential to occur, within the project area includes the following:
South-central California coast steelhead
Steelhead trout (Oncorhynchus mykiss) are the anadromous form of rainbow trout (McEwan
and Jackson 1996). Steelhead historically ranged from Alaska southward to the California-
Mexico border, though current data suggests that the Ventura River is presently the
southernmost drainage supporting substantial steelhead runs. Periodically, steelhead are
reported within the Santa Clara River and Malibu Creek. Southern steelhead are important in
that they represent the southernmost portion of the native steelhead range in North America,
having ecologically and physiologically adapted to seasonally intermittent coastal California
streams.
Optimal habitat for steelhead throughout its entire range on the Pacific Coast can generally be
characterized by clear, cool water with abundant instream cover (e.g., submerged branches,
rocks, logs), well-vegetated stream margins, relatively stable water flow, and a 1:1 pool-to-riffle
ratio (Raleigh et al. 1984). However, steelhead are occasionally found in reaches of streams
containing habitat which would be considered less than optimal. Steelhead within the central
coast region begin moving up coastal drainages (including San Luis Obispo Creek) following the
first substantial rainfall of the fall season. Spawning typically occurs in the spring in riffle areas
that consist of clean coarse gravels. Deposited eggs incubate for approximately 3 to 4 weeks,
with hatched fry rearing within the gravel intersticies for an additional 2 to 3 weeks. Emergent
fry rear at the stream margins near overhanging vegetation. Juveniles (smolts), after rearing for
1 to 3 years within freshwater, and post-spawning adults out-migrate to the ocean from March to
July, depending on streamflows. Therefore, juvenile steelhead can be found within San Luis
Obispo Creek at all times of the year, while adults are more likely to be found from February to
July.
All populations of steelhead occurring within the South-Central California Coast Distinct
Population Segment (DPS) Region – which is defined as that geographic region north of the
Santa Maria River, northward to (and including) the Pajaro River (and its tributaries), Santa Cruz
County – were listed as Federally Threatened by the National Marine Fisheries Service (NMFS)
in August 1997 and recently reaffirmed by NMFS in their 2015 stock update. Southern
steelhead trout are also considered a California Species of Special Concern. The National
Marine Fisheries Service (NMFS) lists habitat deterioration due to sedimentation and flooding
related to land management practices, and potential genetic interaction with hatchery rainbow
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trout, as risk factors to steelhead within the ESU. This species is protected under the Federal
Endangered Species Act.
San Luis Obispo City Biologist Freddy Otte has previously reported that steelhead spawning
has occurred immediately upstream of the Marsh Street bridge. An individual steelhead and
associated redd were observed immediately upstream of the Madonna Road Bridge in 2009.
Between the Marsh Street Bridge and the Madonna Road Bridge, San Luis Obispo Creek
typically goes dry in the summer. There are several deep pools in the project area that could
support over-summer rearing in a normal winter rainfall regime.
California red-legged frog
California red-legged frog (CRLF) (Rana draytonii) is federally listed as threatened and a state
species of special concern, and is known to occur in central coast watersheds from Point Reyes
National Seashore south to Baja California. Counties that support the greatest number of
occupied drainages include Monterey, San Luis Obispo, and Santa Barbara (USFWS Federal
Register 1996). CRLF require specific habitat characteristics for breeding and upland habitat.
Breeding habitat is characterized by still to slow moving water containing emergent vegetation.
Breeding occurs following large rain events between the months of November and March.
Reddish brown egg masses are laid on emergent vegetation and float at the surface of the
water. Upland habitat is necessary for the survival of this species and includes small mammal
burrows, leaf litter, downed trees, and dense riparian vegetation. CRLF are generally found in
riparian vegetation within 30 meters (100 feet) of a water source, but can move up to 2 miles
between aquatic sites to escape drying areas, forage, or breed (USFWS Federal Register
1996). The project site does not support breeding habitat, but does supports marginal upland
dispersal habitat for this species.
Monarch butterfly
The overwintering habitats for this species are of special concern and protected by the
California Department of Fish and Wildlife. Monarch butterfly uses eucalyptus woodland, as well
as other habitat types for winter roosting. Primary roost sites occur in Montana de Oro and
Morro Bay state parks, scattered areas throughout the communities of Los Osos, Morro Bay,
and Pismo Beach State Park. There are several known aggregation sites within the City of San
Luis Obispo, including in eucalyptus trees at Laguna Lake Park and in oak/eucalyptus woodland
on Cerro San Luis Obispo (County of San Luis Obispo 2010). There is potential for winter
roosting within the project area, although regularly occurring, large aggregations are not
expected and have not been observed, probably due to the project’s inland location and the lack
of large clusters of trees to provide necessary microhabitat conditions (primarily wind protection
and adequate sunlight).
Bats
The site visit on May 10, 2010 revealed evidence of bat roosting beneath the Bianchi Lane
Bridge over San Luis Obispo Creek, but none under the Marsh Street Bridge. No bats were
present at the time of the survey, indicating that the roost is used seasonally or as a night roost.
No day roosting bats were observed under the Bianchi Lane Bridge during a March and August
2016 survey. Three sensitive bat species have the potential to occur within the project area, and
are discussed below. No bats were observed during the biological surveys.
Townsend’s big-eared bat (Corynorhinus townsendii). Townsend’s big-eared bat is a federal
Species of Concern and a California Species of Special Concern. Known to occur in caves, tree
cavities and under bridges; most abundant in mesic (wet) habitats. Potential roosting habitat
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exists within the project area, however because this species is extremely sensitive to
disturbance of roosting sites, roosting is very unlikely. The nearest documented location is on
Camp San Luis Obispo north of Highway 1.
Pallid bat (Antrozous pallidus). Pallid bat is a California Species of Special Concern. It is found
in deserts, grasslands, shrublands and forests. The species is most common in open, dry
habitats with rocky areas for roosting. Potential roosting habitat exists within the Project area,
but pallid bat was not observed during the surveys. The nearest known location is approximately
0.5 mile upstream from the project site.
Yuma myotis (Myotis yumanensis). Yuma myotis is a California Species of Special Concern.
This bat is common and widespread in California, and usually forages over water sources such
as ponds, streams and stock tanks. This species is known to roost in buildings, caves, old
buildings, crevices and in bridges. Potential roosting habitat occurs within the project area.
Avian Species
The San Luis Obispo Creek corridor provides foraging, roosting, and nesting habitat for
numerous avian species, including special-status species such as Cooper’s hawk. Given the
narrow width and disturbed nature of the habitat within the project corridor, the potential for
special-status species to occur is reduced relative to the creek corridor in general. Nevertheless,
species such as Cooper’s hawk and yellow warbler, as well as numerous other migratory birds
are known to occur within the project area. A complete list of wildlife observed during biological
resources surveys is included in Appendix D.
4.3.3 Regulatory Setting
4.3.3.1 Federal Policy and Regulations
National Environmental Policy Act
The National Environmental Policy Act (NEPA) provides a framework for environmental
planning by federal agencies and contains action-forcing procedures to ensure that federal
agency decision makers take environmental factors into account. NEPA applies whenever a
federal agency proposes an action, grants a permit, or agrees to fund or otherwise authorize
any other entity to undertake an action that could possibly affect environmental resources. It is
anticipated that the USACE will act as federal lead agency for this project as they will be issuing
a permit in accordance with Clean Water Act (CWA) requirements.
Section 404 of the Clean Water Act of 1977
The USACE is responsible for the issuance of permits for the placement of dredged or fill
material into “waters of the United States” pursuant to Section 404 of the CWA (33 United
States Code [USC] 1344). As defined by USACE at 33 CFR 328.3(a)(parts 1-6), the following
summarizes “Waters of the United States” as:
“Those waters that are currently used, or were used in the past, or may be susceptible to use in
interstate or foreign commerce, including all waters which are subject to the ebb and flow of the
tide; tributaries and impoundments to such waters; all interstate waters including interstate
wetlands; and territorial seas.”
The project would place fill, in the form of vegetated rock slope protection and cofferdams,
within “waters of the U.S.”, in this case San Luis Obispo Creek. Therefore, the project would be
subject to Section 404 of the CWA.
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Section 401 of the Clean Water Act of 1977
Section 401 of the CWA and its provisions ensure that federally permitted activities comply with
the CWA and state water quality laws. Section 401 is implemented through a review process
that is conducted by the RWQCB, and is triggered by the Section 404 permitting process
described above. The RWQCB certifies via the 401 process that a proposed project complies
with applicable effluent limitations, water quality standards, and other conditions of California
law. Evaluating the effects of the proposed project on both water quality and quantity (runoff)
falls under the jurisdiction of the RWQCB. The proposed project has the potential to result in
impacts to water quality and quantity, and therefore compliance with Section 404 of the CWA.
Therefore, the proposed project would also require compliance with Section 401 of the CWA,
requiring certification by the RWQCB.
Federal Endangered Species Act (FESA)
FESA, administered by the USFWS and NMFS, provides protection to species listed as
threatened or endangered. FESA also provides protection to those species proposed to be
listed under FESA. In addition to the listed species, the Federal government also maintains lists
of species that are neither formally listed nor proposed, but could potentially be listed in the
future. Species on this list receive “special attention” from federal agencies during
environmental review, although they are not protected otherwise under the FESA. The
candidate species include taxa for which substantial information on biological vulnerability and
potential threats exist, and are maintained in order to support the appropriateness of proposing
to list the taxa as an endangered or threatened species. USFWS and NMFS also regulate
activities conducted in federal critical habitat, which are geographic units designated as areas
that support primary habitat constituent elements for listed species.
Due to the presence and/or potential of federally listed species within the project area, including
steelhead and California red-legged frog, compliance with Section 7 of FESA would be required.
Potential impacts to listed species resulting from the implementation of a project would require
the responsible agency or individual to formally consult with the USFWS or NMFS to determine
the extent of impact to a particular species.
Migratory Bird Treaty Act (MBTA)
The MBTA of 1918 protects all migratory birds, including their eggs, nests, and feathers. The
MBTA was originally drafted to put an end to the commercial trade in bird feathers, popular in
the latter part of the 1800’s. The MBTA is enforced by the USFWS, and potential impacts to
species protected under the MBTA are evaluated by the USFWS in consultation with other
federal agencies. Numerous migratory bird species were observed within the project corridor
during surveys.
4.3.3.2 State Policy and Regulations
California Endangered Species Act (CESA)
The CESA ensures legal protection for plants listed as rare or endangered, and wildlife species
formally listed as endangered or threatened. The state also maintains a list of SSCs. SSC status
is assigned to species that have limited distribution, declining populations, diminishing habitat;
or unusual scientific, recreational, or educational value. Under state law, the CDFW is
empowered to review projects for their potential to impact special-status species and their
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habitats. Under CESA, CDFW reserves the right to request the replacement of lost habitat that
is considered important to the continued existence to CESA protected species. Take of state-
listed species would require a Section 2081 Incidental Take Permit from the CDFW. Due to the
lack of state listed species within the project corridor, it is unlikely that a Section 2081 Incidental
Take Permit will be necessary.
California Fish and Game Code
California Fish and Game Code §3511 includes provisions to protect Fully Protected (FP)
species, such as: (1) Prohibiting take or possession "at any time" of the species listed in the
statute, with few exceptions; (2) stating that "no provision of this code or any other law shall be
construed to authorize the issuance of permits or licenses to "take" the species; and (3) stating
that no previously issued permits or licenses for take of the species "shall have any force or
effect" for authorizing take or possession. CDFW is unable to authorize incidental take of "fully
protected" species when activities are proposed in areas inhabited by those species.
Sections 3503 of the Fish and Game Code state that it is “unlawful to take, possess, or destroy
the nest or eggs of any bird, with occasional exceptions.” Section 3503.5 of the Fish and Game
Code states that it is “unlawful to take, possess, or destroy any birds in the order Falconiformes
or Strigiformes (birds of prey) or to take, possess, or destroy the nest of eggs of any such bird
except as otherwise provided by this code or any regulation adopted pursuant thereto.” In
addition, §3513 states that it is unlawful to take or possess any migratory bird as designated in
the MBTA or any part of such migratory birds except as provided by rules and regulations under
provisions of the MBTA. White-tailed kite is a fully protected species under §3511 and has a
potential, albeit a low potential, to occur within the project corridor.
CDFW also manages the California Native Plant Protection Act of 1977 (Fish and Game Code
Section 1900, et seq), which was enacted to identify, designate, and protect rare plants. In
accordance with CDFW guidelines, California Native Plant Society (CNPS) 1B list plants are
considered “rare” under the Act, and are evaluated in CEQA documents.
Section 1602 of the Fish and Game Code
CDFW is responsible for conserving, protecting, and managing California's fish, wildlife, and
native plant resources. To meet this responsibility, the law requires any person, state or local
government agency, or public utility proposing a project that may impact a river, stream, or lake
to notify the CDFW before beginning the project. If the CDFW determines that a project may
adversely affect existing fish and wildlife resources, a Lake or Streambed Alteration Agreement
(SAA) is required. A SAA lists the CDFW conditions of approval relative to the proposed project,
and serves as an agreement between an applicant and the CDFW. As proposed the project
would require a SAA from CDFW.
4.3.4 Significance Criteria
The significance of potential biological impacts is based on Appendix G of the State CEQA
Guidelines. Using these guidelines, activities requiring CEQA review within the project corridor
would have a significant impact on biological resources if they would:
1. Result in a loss of unique or special-status species or their habitats;
2. Reduce the extent, diversity or quality of native or other important vegetation;
3. Impact wetland or riparian habitat;
4. Interfere with the movement of resident or migratory fish or wildlife species, or factors,
which could hinder the normal activities of wildlife; or
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5. Conflict with any regional plans or policies to protect sensitive species, or regulations of
the California Department of Fish & Wildlife or U.S. Fish & Wildlife Service.
4.3.5 Impacts and Mitigation Measures
This section describes impacts related to construction of the project and is organized based on
the significance criteria outlined above and the data provided in the two tables below. Impacts to
vegetation communities are shown in Table BR-1. Temporary impacts would result from all
components of the project including the dewatering, the bridge replacement, the flow return, and
the bypass channels. Installation of the vegetated rock slop protection is considered a
temporary impact.
Table BR-1. Impacts to Vegetation Communities
Vegetation Community Temporary
Impacts
Nonnative grassland/Ruderal 4.09
Riparian Forest 2.38
Riverine 1.56
Total 8.03
Approximately 128 mature native trees would be removed during construction of the project,
primarily at the four benches, as well as at the confluences of the bypass channels and the
creek channel. The species and number of each species to be removed are shown in Table BR-
2. It may be possible to protect some of the trees from impact during construction, but that
cannot be concluded with certainty until much closer to project construction; therefore, this
evaluation assumes that all trees indicated “to be removed” or where “removal may be
necessary” in the project plans (Appendix B), would be removed.
Table BR-2. Tree Removal
Common Name Scientific Name Number
Bay laurel Umbellularia californica 2
California black walnut Juglans californica 16
Coast live oak Quercus agrifolia 7
California sycamore Platanus racemosa 1
Black cottonwood Populus trichocarpa 14
Arroyo willow (primarily) Salix lasiolepis 88
Total 128
Nonnative/ornamental Multiple, primarily
Eucalyptus globulus 24
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Impacts to jurisdictional areas are focused primarily in the areas where bypass channels
intercept the existing creek channel and at the four bench locations. Impacts to jurisdictional
areas are shown in Figure BR-1 and in Table BR-3. Representative photos of the primary
impact areas are included in Appendix D. USACE impact area equals the ordinary high water
mark (OHWM). No other waters of the US were identified within the project area. The CDFW
and RWQCB impact area includes the edge of the San Luis Obispo Creek riparian corridor.
Table BR-3 Impacts to Jurisdictional Features (acres)
Jurisdictional
Feature Project Component Temporary
Impacts
Permanent
Impacts
USACE All areas of the OHWM between 3
sets of dewatering cofferdams 1.56 0.191
Total 1.56 0.00
CDFW /
RWQCB
Bypass channels/vegetated RSP2 1.18 0.191
Benches, Flow Return, Marsh St
sediment removal1 1.20 0.00
3 dewatered areas/OHWM Impacts 1.56 0.00
Bianchi Lane Bridge Center and
Eastern Supports Included above 0.01
Total 3.94 0.20
1. These permanent impacts include the vegetated RSP, root wads and flow deflectors, which would be
considered “beneficial fill”
2. To avoid double counting, this includes areas inside of CDFW/RWQCB jurisdiction but outside of the OHWM.
This EIR includes mitigation measures that are applicable to the project-specific impacts
identified, and have been applied for similar projects, including those in San Luis Obispo Creek
and County. Further, mitigation measures recommended below include as much detail as
applicable at this stage of the process, but it is likely that they will be refined through the
subsequent resource agency permitting process.
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4.3.5.1 Loss of Unique or Special-status Species or their Habitats
4.3.5.1.1 Special-status Wildlife Impacts
A number of special-status wildlife species are known or have the potential to occur within the
project area and would potentially be impacted by project construction. These species are
described below.
California red-legged frog
There are no recorded occurrences of CRLF in CNDDB records for this or neighboring reaches
of San Luis Obispo Creek; however, CRLF has been observed downstream at the City’s Water
Recycling Facility (Caltrans 2008). The proposed project would not impact any potential CRLF
breeding habitat, but may impact foraging habitat and aquatic dispersal/summer habitat. These
impacts may result from dewatering activity and/or from clearing riparian vegetation, which
would result in a temporary loss of potential foraging and dispersal habitat. Construction
activities, which include the use of heavy equipment in and adjacent to riparian habitat, would
potentially impact foraging or dispersing CRLF.
BR-Impact 1 California red-legged frog may be directly impacted during construction
activities.
BR-mm 1 Through the USACE permit process, conduct consultation with the USFWS to
develop avoidance and minimization measures for the CRLF. These measures
may include, for example, the measures described in the 1999 CRLF
Programmatic Biological Opinion between the USFWS and the USACE.
Residual Impact. The Programmatic Biological Opinion (BO) measures referred to in BR-mm 1
are included in Appendix D. The BO measures include pre-construction surveys, identifying
potential relocation sites, and using only qualified biologists to implement the measures.
Implementation of BR-mm 1, will reduce potential direct impacts to a less than significant level.
No additional measures are required.
South-central California Coast Steelhead
This section first describes potential construction-related impacts to steelhead, and then
describes potential longer-term impacts to steelhead habitat within the project area. Within the
project area San Luis Obispo Creek supports rearing habitat for juvenile steelhead, and is a
known migration corridor for adult steelhead and out-migrating juveniles, including steelhead
smolts. Gravel bars present in the vicinity of the project area may support spawning of adult
steelhead, although to what extent adults use this habitat for spawning is unknown.
Construction-Related Impacts to Steelhead
The project could directly impact steelhead during project construction activities occurring in the
wetted (below the OHWM) portion of the channel. Project activities within the channel would
occur in the driest portion of the year, outside of the peak steelhead migration period of March
through May (Caltrans 2008), thereby reducing potential impacts, although some steelhead are
expected to be in the project area during the construction period. Steelhead would potentially be
impacted during the dewatering process as they could be stranded, trapped, or injured during
handling and relocation.
BR-Impact 2 South-central California coast steelhead may be directly impacted during
construction activities.
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BR-mm 2 Construction requiring stream dewatering, stream crossings, or work in the
channel bed will not start before June 1. Upstream and downstream passage for
fish, including juvenile steelhead, will be provided through or around construction
sites at all times. Cofferdams will be installed to divert streamflow around each
in-stream construction area.
BR-mm 3 Through the USACE permit process, conduct consultation with the NMFS to
develop avoidance and minimization measures for steelhead. These measures
may include, for example, having a qualified biologist onsite during the
installation of cofferdams and during the cofferdam dewatering process to
capture and move trapped salmonids and other fish as well as identifying the
appropriate procedures for relocating fish. Protocols for the capture, handling,
and release of fish will be developed in cooperation with NMFS and CDFW and
implemented during project construction.
Residual Impact. Implementation of BR-mm 2 and 3 will reduce potential construction-related
impacts to a less than significant level. No additional measures are required.
Long-term Impacts to Steelhead Habitat
During the environmental review process for the WMP, which included a more general
assessment of potential bypass projects, a number of potential longer-term impacts to steelhead
and their habitat were identified. These included impacts to riparian and upland habitat,
increased erosion and sedimentation, disturbance of spawning gravels, changes in hydrology,
and the potential entrapment of fish in modified/new channels. The EIR/EIS also concluded that
more project-specific environmental review should be performed for capital projects, such as the
proposed project.
NMFS commented on the WMP Draft EIR/EIS, echoed the comments provided on the WMP,
and suggested that channel modification, the creation of new channels, and the use of rip-rap
would potentially reduce channel complexity, and negatively affect the creek’s function and
value as steelhead habitat. The NMFS comment letter is included in the WMP Final EIR/EIS,
which is available for review at the District office. The letter from NMFS recommends that further
environmental analysis should accomplish five things to reduce uncertainties in the steelhead
assessment. Those five things, and a discussion of how they have been addressed, is included
below.
1. Define a system for estimating the number of steelhead that may be affected by project-level
activities.
As described above, assuming implementation of a comprehensive dewatering plan, no fish
mortality is expected to result from construction of the project. There is the potential that if
fish use the bypass channel, they could become stranded in the channel if ponds form as
the water recedes. Fish stranding would be unlikely because the bypass channels would
only be active for limited periods of time. For example, the baseline flow for this stretch of
the creek is 146 cfs. The Bianchi Bypass and South Street Bypass would activate at 1,790
and 440 cfs respectively. During a 2-year storm these bypass channels would flow for
approximately 3.5 and 15 hours respectively. The bypass channels would be active during a
100-year storm for less than 19 hours.
In addition, the bypass channels would be unattractive to migrating steelhead as they
provide little habitat/cover, only function during higher flow events, and they would be sloped
at approximately 2% downstream to discourage ponding. Additionally, habitat improvements
such as scour pools and root wads are proposed at the channel transition areas to
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encourage fish to hold in the main channel. To further avoid potential fish stranding, two
additional mitigation measures are included below. These measures require use of boulder
clusters at the upstream transition areas to provide additional holding habitat in the main
channel, and they require post-storm monitoring of the bypass channels to identify any
potential ponded water and fish that may be stranded.
2. Define a process for measuring the type, quantity, and quality of habitat that is affected by
project-level activities.
During development of the WMP and this Supplemental EIR, the habitat characteristics of
the project area, which is part of Reach 10, were evaluated. As described in section 4.3.2.2,
Reach 10 has one of the lowest pool to riffle ratios in the creek system, is 92% flatwater
habitat, and has an understory largely consisting of non-native, invasive vegetation. Recent
assessments of the area conducted as a part of this Supplemental EIR process confirm that
these conditions remain consistent with those first described in the WMP. Impacts to
jurisdictional areas and vegetation communities as well as mitigation measures that address
those impacts are described in Sections 4.3.5.2 through 4.3.5.4 below. In addition,
mitigation measure BR-mm 7 proposed below requires a quantitative assessment of Reach
10 similar to what was performed for the WMP, be performed prior to construction, and
regularly post-construction. These follow-up assessments would be performed in
coordination with revegetation monitoring. Together these measures would confirm whether
or not the project has had long-term impacts to the biological resources within the project
area.
3. Outline the compensatory mitigation program that will be implemented to offset effects of
project-level activities on steelhead and instream and riparian habitat.
The compensatory mitigation program is outlined in this section of the EIR. It is entirely in-
kind and onsite, and focuses on the replacement of nonnative vegetation with native
vegetation, installation of flow deflectors and rootwads, and utilizes vegetated rip-rap in
places where the use of rock for erosion control and bank stabilization is unavoidable, such
as at bypass channel transition areas. The proposed compensatory mitigation is not based
on typical mitigation “ratios,” but rather, it encompasses a strategy to improve habitat on a
long-term basis.
4. Define a procedure for measuring and detecting spatial and temporal changes in habitat
quality and quantity.
Spatial and temporal changes within the project area may be detected as described above.
Habitat value in the main channel is expected to be improved overall for the reasons
described above (i.e. rootwads, vegetated RSP, removal of invasive vegetation). Further,
the proposed project area includes approximately 75% of the length of Reach 10. By
including the entire reach in follow-up monitoring, the District may gain a better
understanding of unrelated changes in habitat upstream of the project as well.
5. Define a protocol that will track performance of the measures proposed, respond to new
information or changing conditions, and detect and reconcile deficiencies or problems in a
timely manner.
Protocol for tracking the performance of the measures proposed will be developed in the
HMMP, which will be reviewed and approved by the CDFW, RWQCB, and USACE, in
consultation with NMFS and USFWS. HMMPs include performance criteria and outline a
monitoring protocol. In addition, the HMMP will include contingency measures to be
implemented in the event that the proposed measures are not meeting the performance criteria.
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The photo above shows the existing conditions at the proposed upstream end of the Bianchi
Bypass channel from the existing bridge. The figure below illustrates the conceptual root wad
detail that would be installed at this location. The new Bianchi Lane Bridge would be located
upstream from the existing bridge. This area is further described on Sheets C6 in Appendix B of
this EIR.
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BR-Impact 3 Implementation of the project would potentially result in long-term adverse
impacts to the habitat value of the creek for steelhead within the project area.
BR-mm 4 Prior to construction the project plans shall be revised to show the bypass
channels sloped towards the “inside” bank to minimize the potential for ponding
water.
BR-mm 5 Prior to construction the project plans shall incorporate additional boulder
clusters or similar features into the design of the transition areas
BR-mm 6 At the appropriate time following applicable storm events, the bypass channels
shall be inspected to determine the potential for ponded water and to confirm no
fish have been stranded. In the event that special-status fish are observed
stranded in the bypass channels, they shall be relocated by a qualified biologist
consistent with necessary permits and authorizations.
BR-mm 7 Prior to construction and following construction at appropriate intervals, the
habitat assessments consistent with those performed for the WMP shall be
conducted by qualified biologists. These efforts shall be described in and
coordinated with habitat restoration monitoring to be described in the HMMP for
the project.
Residual Impact. Implementation of the measures described above would reduce potential
impacts to less than significant levels. No further measures are required.
Monarch Butterfly
Project construction will include substantial disturbance adjacent to large eucalyptus stands and
the removal of a number of large eucalyptus. No CNDDB records of monarch butterfly
overwintering occur within the project corridor, and large populations were not observed during
biological resources surveys for the project. However, the larger trees and stands potentially
provide habitat for overwintering monarch butterfly.
BR-Impact 4 Removal of larger stands of eucalyptus within the project corridor would
potentially impact overwintering monarch butterflies.
BR-mm 8 To avoid impacts to monarch butterflies, construction shall be avoided as feasible
during the monarch butterfly wintering period (November to February). However,
if work is scheduled to occur during this time, the project corridor shall first be
surveyed for overwintering monarch butterfly. If substantial monarch butterfly
population is observed, tree removal shall cease within 200 feet of the
population, and sufficient dust control measures shall be implemented to
minimize dust emissions and associated impacts to any eucalyptus groves within
or directly adjacent to project-related ground disturbance.
Bats
Various bat species, including special-status bats such as pallid bat and Yuma myotis could use
the Bianchi Lane Bridge as a roosting location; however, no day roosting bats were observed
during biological resources surveys. Crevices in trees onsite could provide roosting habitat for
bat species, as well. Construction includes the demolition of the Bianchi Lane Bridge and tree
removal which could impact roosting bats.
BR Impact 5 Demolition of the Bianchi Lane Bridge and tree removal would potentially impact
roosting bats.
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BR-mm 9 Prior to construction, one daytime and one night-time pre-construction surveys
shall be conducted by qualified biologists no more than 30 days prior to
construction to determine if bats are day or night roosting in the project area. The
biologist(s) conducting the preconstruction surveys will also identify the nature of
the bat utilization of the area (i.e., no roosting, night roost, day roost, maternity
roost). If bats are found to be roosting in the surveyed areas, the following
measures will be implemented during construction:
1. If there is only night roosting by bats and the roost substrate will not be
impacted, work may proceed as normal provided that no night-time work
is scheduled.
2. If there is day roosting by bats (or night roosting and work during
nighttime), qualified biologists shall monitor any construction activities
within 100 ft for disturbance to bat roosting. If bat roosting behavior is
determined to be adversely impacted by construction activities,
construction must be avoided in the vicinity of bat roosts until either bats
are no longer roosting or they have been excluded from roosting.
3. If maternity roosts are detected, construction activities must be avoided
within 100 ft (30 m) of an active maternity roost until the end of the
maternity roosting season (end of September). No roost exclusion shall
be conducted if maternity roosts are detected.
4. Readily visible exclusion zones shall be established in areas where roosts
must be avoided.
BR-mm 10 The design of the new Bianchi Lane Bridge shall incorporate bat friendly features
and/or provide areas where manmade roosts can be easily attached during
construction. If manmade roosts are to be attached to the bridge, this shall be
accomplished prior to the conclusion of construction activities.
Residual Impact. Implementation of BR-mm 5 will reduce potential impacts to bat species to a
less than significant level. No additional measures are required.
4.3.5.1.2 Special-status Plant Impacts
During preparation of the 2010 Habitat Assessment and subsequent follow-up analysis, a
records search was conducted to identify special-status plant species with the potential to occur
within the project site. References included the CNDDB and the Los Osos Valley Road/Highway
101 Interchange environmental documents, which were completed in 2011 for a large project
approximately 1.5 miles downstream. During multiple surveys of the project area for the WMP,
2010 Habitat Assessment, and this EIR, no special-status plant species were identified.
No impacts to special-status plant species would result from the project, and no mitigation is
required.
4.3.5.2 Reduce the Extent, Diversity, or Quality of Native or Other Important Vegetation
As shown in Table BR-1, three vegetation communities would be impacted by the project. Two
of these communities, Riparian Forest and Riverine, could be considered “native and important”
to the function and value of the creek corridor, although as described above, the habitat
provided is of relatively low quality due to the urban encroachment and substantial nonnative
vegetation. As currently proposed, despite the impacts to the vegetation communities above,
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the project is expected to result in improvements to the value of the habitat along San Luis
Obispo Creek. This is due to the following:
x Non-native trees removed during construction would be replaced with native species
x Trash and other debris encountered during construction would be removed.
x Root wads and flow deflectors would be installed within the channel to increase habitat
complexity in the channel by increasing the percentage of pools and riffles within the
reach (refer to Sheet C7 of the project plans).
x Populations of invasive species within the construction area would be removed and all
disturbed areas would be revegetated with native species.
While the area of disturbance is one measure of the temporary impacts resulting from
construction, due to the large percentage of nonnative species that create the understory,
another measure of impacts is the tree removal required for the project. As currently proposed,
the project would result in the removal of up to 152 mature trees. Up to 128 of these trees are
native species, including, but not limited to coast live oak, valley oak, cottonwood, walnut, and
arroyo willow.
The loss of this vegetation during construction will result in a temporary reduction in roosting,
foraging and nesting habitat for birds and other wildlife. The temporary absence of overstory
vegetation will result in impacts to aquatic organisms by reducing shading, increases in water
temperature, and possibly increased algae growth. These impacts are expected to last several
years, with improvement each year, until proposed revegetation matures. In the longer-term, the
reduction in willows along the corridor may reduce the amount of mid-level vegetation available
to birds for foraging, roosting and nesting, and will reduce the numbers of insects available to
animals (including fish) which feed on these invertebrates. Increased penetration of sunlight
may also encourage the proliferation of some undesirable plant species, which in turn could
make native plant restoration more challenging. At the same time, the reduction in non-native
and invasive species, as well as increased channel complexity are considered beneficial
impacts of the project.
Consistent with the long-term management goals of the WMP Drainage Design Manual Figure
11-2 and as shown on Sheet V1, Appendix B of the project plans, willows, as well as any
nonnative tree species, would be replaced with “native, erect, single-trunked species” such as
cottonwood, maple and bay, in order to provide stormwater capacity while enhancing habitat.
Native trees removed by the project would be replaced at an approximately 2:1 ratio and
planted in clusters as shown in Figure 11-2, Appendix B.
BR Impact 6 Project construction will impact approximately 3.94 acres of riparian forest and
riverine communities combined, and result in the removal of approximately 128
native trees, impacting the riparian habitat for wildlife.
BR-mm 11 Prior to construction, the project proponent will retain a qualified biological
monitor(s) to monitor construction and ensure compliance with Avoidance and
Minimization Measures within the project environmental documents.
BR-mm 12 Before any activities begin on a project, a qualified biologist shall conduct a
training session for all construction personnel. At a minimum, the training shall
include a description of the important vegetation and special-status resources
that occur in the project area, the specific measures that are being implemented
to conserve them and the boundaries within which the project may be
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accomplished. Brochures, books, and briefings may be used in the training
session, provided that a qualified person is on hand to answer any questions.
BR-mm 13 During construction, work within the creek shall be conducted when the creek
does not contain flowing or standing water, if feasible. If work activities must
occur when water is present in the creek channel, the contractor shall dewater
the creek prior to conducting the activities.
BR-mm 14 Prior to any construction work beginning, including any vegetation clearing,
sturdy high visibility fencing shall be installed to protect jurisdictional areas and
sensitive resource areas adjacent to the work area. This fencing shall be placed
so that unnecessary impacts to adjacent habitat are avoided. No construction
work (including storage of materials) shall occur outside of the “Project Limits”.
The required fencing shall remain in place during the entire construction period
and maintained as needed by the contractor.
BR-mm 15 During construction, the cleaning and refueling of equipment and vehicles will
occur only within a designated staging area and as far from aquatic areas as
feasible. At a minimum, all equipment and vehicles will be checked and
maintained on a daily basis to ensure proper operation and avoid potential leaks
or spills.
BR-mm 16 During construction, the biological monitor(s) will ensure that the spread or
introduction of invasive exotic plant species is avoided to the maximum extent
possible. When practicable, invasive exotic plants in the project site will be
removed and properly disposed.
BR-mm 17 During construction, trash will be contained, removed from the work site, and
disposed of regularly. Following construction, all trash and construction debris
will be removed from work areas. All vegetation removed from the construction
site shall be taken to a certified landfill to prevent the spread of invasive species.
BR-mm 18 During construction, no pets will be allowed on the construction site.
BR-mm 19 Prior to construction, a comprehensive Habitat Mitigation and Monitoring Plan
(HMMP) shall be prepared that reflects the guidance of the WMP and includes
the following guidelines:
1. Results in an improved pool to riffle ratio, reduction in invasive species, and
increase of canopy cover provided by native species for Reach 10 compared
to the 2002 assessment.
2. A 1:1 replacement ratio for temporary impacts to riverine and riparian
vegetation communities.
3. A 2:1 replacement ratio for permanent impacts to riverine and riparian
communities.
4. A replacement ratio for native trees and shrubs impacted by the project that
will result in equal to or better habitat conditions within the project corridor as
quickly as feasible.
5. Considers invasive species and debris removal in-lieu of a strict tree
replacement ratio where appropriate.
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6. Allows for flexibility in species to be planted so that predominately single-
trunk species such as black walnut, black cottonwood, and bay laurel can be
substituted for willows, for example.
7. Takes advantage of the bypass channels and terraces between the bypass
channels and the creek to replace the ruderal and nonnative annual
grassland vegetation communities with riparian and native upland ones, even
in areas not directly impacted by the project construction.
BR-mm 20 During construction, the project will make all reasonable efforts to limit the use of
imported rock. Imported material should be obtained from a source that is known
to be free of invasive plant species; or the material must consist of purchased
clean material such as crushed aggregate, sorted rock, or similar.
Residual Impact. Implementation of BR-mm 7 through BR-mm 16, along with the development
of plans such as the Dewatering and Diversion Plan, the Spill Prevention and Control
Contingency Plan, and the Stormwater Pollution Prevention Plan which will all be prepared
subsequently, will reduce potential impacts to important natural communities to a less than
significant level. No additional measures are required.
4.3.5.3 Impact Wetland or Riparian Habitat
San Luis Obispo Creek is a perennial stream and would be considered “other waters” by the
USACE. The area of other waters corresponds with the Riverine vegetation community
described above, and the OHWM of the creek. During surveys for the project no off-channel,
adjacent, or other wetlands were observed. Impacts to the other waters and Riparian Habitat
are also described above.
4.3.5.4 Interfere with the Movement of Resident or Migratory Fish or Wildlife Species, or
Factors, which Could Hinder the Normal Activities of Wildlife?
Potential impacts to fish and other wildlife have been described previously. To avoid
redundancy, this section includes only a discussion of migratory avian species. Several special-
status avian species such as Cooper’s hawk and non–sensitive migratory birds could nest in
and adjacent to the project area. A complete list of avian species observed during biological
resource surveys is included in Appendix D. The breeding season for most birds is generally
from February 15 to September 1, peaking from April through June, with exceptions. Cooper’s
hawk is designated as a state species of special concern. Construction is expected to begin in
the dry season, approximately April 15 at the earliest. Birds nesting in the project corridor could
be disturbed by the noise, dust and similar disturbances such that they abandon a nest. Further,
nests could be directly impacted during tree removal, grading, and similar activities.
BR-Impact 7 Construction activities would result in impacts to nesting avian species
BR-mm 21 To protect special-status avian species and those species protected by the
MBTA, the District shall avoid vegetation clearing and earth disturbance during
the typical nesting season (February 15 to September 1). If avoiding construction
during this season is not feasible, a qualified biologist shall survey the area within
one week prior to activity beginning on site. If nesting birds are located on or near
the proposed project site, they shall be avoided until they have successfully
fledged. A buffer zone of 50 feet will be placed around all non-sensitive,
passerine bird species, and a 250-foot buffer will be implemented for raptor
species, and all activity will remain outside of that buffer until the qualified
biologist has determined that the young have fledged. Buffer reductions and/or
work within non-disturbance buffer areas can be completed only with approval
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from relevant resource agencies.
Residual Impact. Implementation of BR-mm 16 will reduce potential impacts to a less than a
significant level. Measures BR-6 through 15 will reduce indirect impacts and short-term impacts
to vegetation in the project corridor that may be used as habitat for nesting birds to a less than
significant level. No additional measures are required.
4.3.5.5 Conflict with any Regional Plans or Policies to Protect Sensitive Species, or
Regulations of the California Department of Fish & Wildlife or U.S. Fish & Wildlife
Service
Critical habitat was redesignated for south-central California coast steelhead by NOAA Fisheries
(70 FR 52574, September 2, 2005). San Luis Obispo Creek is included in the critical habitat
designation. As described above, the project would potentially directly impact steelhead during
dewatering operations, and result in potential indirect temporary impacts through the short-term
loss of riparian and riverine habitat, resulting in secondary in this habitat. Potential impacts and
mitigation is described above. No additional mitigation is required.
4.3.6 Cumulative Impacts
Implementation of the Waterway Management Plan as well as the other projects identified in the
Cumulative Development Scenario, when considered along with the proposed project, could
have a significantly cumulative impact to the San Luis Obispo Creek watershed. These impacts
include the temporary loss of riparian vegetation, use of heavy equipment within the riparian
corridor, and in some cases the low-flow channel, as well as possible indirect impacts to wildlife
along the corridor through the introduction of additional recreational uses within the corridor.
However, projects that potentially directly affect San Luis Obispo Creek are generally highly
regulated. The proposed project would require permits or other authorizations from regulatory
agencies including the USACE, RWQCB, CDFW, USFWS, and NMFS. These agencies are
responsible to authorize projects that avoid, minimize, and/or mitigate impacts to habitats,
jurisdictional waters, and sensitive plant and wildlife species. The projects listed in the
cumulative development scenario are also potentially subject to regulations by all of these
agencies.
In addition, there are ongoing efforts by the City of San Luis Obispo, and the San Luis Obispo
Land Conservancy to improve habitat value within the creek watershed – the ongoing Arundo
removal projects, for example, as well as the upgrade to the City’s Water Recycling Facility.
These projects, along with the propped project enhancement activities will result in cumulative
beneficial impacts to the watershed and the species potentially impacted by the proposed
project, including the CRLF and steelhead. As a result, no mitigation beyond that already
discussed in this EIR is required to address the project’s potential contribution to cumulative
impacts.
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4.4 Cultural Resources
This section describes potential impacts to cultural (historic and/or prehistoric) resources that
may result from the project. The information that follows relies primarily on two documents, the
EIR/EIS and the Archaeological Survey Report (ASR) prepared for the project (County of San
Luis Obispo 2011).
4.4.1 Methodology
The ASR prepared for the project included a records search and a pedestrian survey. The
records search was conducted for all known archaeological sites, historic resources, and
surveys within the project corridor (referred to as the Area of Potential Effect [APE] in the ASR).
A search of the inventories for the State Historic Property Data Files, National Register of
Historical Landmarks, California Points of Historic Interest, California OHP Archaeological
Determinations of Eligibility, and the Caltrans State and Local Bridge Surveys yielded six
property evaluations within the search radius.
The records search revealed that much of the corridor has previously been subject to cultural
resources surveys between 1978 and 2008. Several surveys have been conducted along South
Higuera Street, and one focused on Highway 101’s right of way through the length of th e project
area. The creek banks have also been surveyed, twice. In all, 25 surveys have been conducted
and five historic properties have been recorded within the search area. No prehistoric sites have
been recorded in the project corridor.
The project corridor was visually inspected on May 5, and May 10, 2010. The limits of the APE
were surveyed in several meandering transects, focusing on bare soils and exposed creek
banks. All bare soils and gopher burrows were inspected for the presence of cultural materials.
Ground surface visibility varied between completely obscured (asphalt areas) and approximately
30%. The majority of the survey area consisted of non-native annual grassland and riparian
vegetation. Survey of the creek banks was obscured by sacrete and rubble walls, and dense
riparian vegetation.
4.4.2 Existing Conditions
The project area was prehistorically inhabited by the Obispeño Chumash. The Chumash and
their ancestors have inhabited San Luis Obispo County for at least 10,000 years (Greenwood
1972; Fitzgerald et al. 1998). The Northern Chumash, or Obispeño, are the northernmost
Chumash speaking peoples of California and ranged from the Pacific Coast east to the coastal
ranges and from the Santa Maria River north to San Simeon or beyond.
The Chumash developed a complex system of social organization rarely observed in other
hunting and gathering groups in the world. The Obispeño were hunter-gatherer-fishers who
resided in both ephemeral camps and permanent villages. Many of the coastal sites are easily
identifiable due to their high density of shellfish remains while many of the interior sites
(including sites in the project vicinity) are identified predominantly through the presence of
flaked stone tool manufacture remains. The Chumash were adept at recovering not only
shellfish, but also hunted small and large game, waterfowl, and gathered a large assortment of
plants including acorns as a staple food. The Chumash are also world-renown for their
elaborate basketry.
After the Mission system was established in 1772 in San Luis Obispo and soon after in Santa
Barbara, Santa Inez, San Buenaventura, and La Purisima, Chumash populations immediately
declined, resulting in near extinction of the people by the early 1900s. Today, descendants of
these groups continue to live in San Luis Obispo, Santa Barbara, and Ventura Counties.
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The historic period begins with Spanish exploration of California in 1542. In 1822, California
became a Mexican territory and the lands of the Mission were secularized and disbanded by
1834. The County of San Luis Obispo was established in 1850, and at that time, the area to
become the City of San Luis Obispo consisted of approximately 150 buildings. The City was
incorporated in 1876. Also in 1876, the San Luis Obispo and Santa Maria railroad was
completed between Port San Luis (then called Port Harford) and the City. The Pacific Coast
Railroad terminal was located near the intersection of South Higuera and South Streets, just
east of the project corridor. The railroad operated a roundhouse and warehouses until the
1930s. The San Luis Lumber company was serviced by the railroad and occupied the entire
block bounded by Higuera, Beebee, South, and High Streets.
The Smith and Waites Planing Mill and Machine Shop was established in 1883 where Haywood
Lumber currently exists northwest of the intersection of South Higuera Street and South Street
east of the creek. Construction of the railroads brought immigrants from China and Great
Britain. Dairying was an important industry in the County in the early 20th century, attracting
farmers of Italian-Swiss descent.
Later, Japanese farm laborers arrived to the City, and settled in the area of lower Higuera, at
South Street. A cluster of six wood frame houses on Brook Street constitute the only remaining
farm labor camp in the City. This area, in the 1930's, was referred to as the "Japanese Village"
and on the pre-1957 Sanborn maps, Brook Street was known as Eto Street. South Higuera
Street served as major thoroughfare even after the Pacific Coast Railroad was closed. Higuera
was (and still is today) lined with automobile repair shops and service stations. Over time, the
Mid-Higuera Street corridor between Madonna and Marsh became less residential and more
industrial. Today, very few homes remain in this area.
Figure CR-1 – Birds Eye View of San Luis Obispo, 1877
Approximate Flow Return Area
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4.4.3 Regulatory Setting
4.4.3.1 State Regulations
California Environmental Quality Act
CEQA (Public Resources Code 21000 et seq.) requires lead agencies to consider the potential
effects of a project on significant historical and archaeological resources. Significant impacts on
such resources are to be avoided or mitigated to less than significant levels. Other state laws
govern actions affecting cemeteries and human remains.
State historic preservation regulations affecting this project include the statutes and guidelines
contained in CEQA (Public Resources Code Sections 21083.2 and 21084.1 and Section
15064.5 of the CEQA guidelines). CEQA requires lead agencies to carefully consider the
potential effects of a project on historical resources. CEQA Guidelines provides criteria for
determining the significance of a cultural resource. This section states the following:
“Generally, a resource shall be considered by the lead agency to be “historically significant” i f
the resource meets the criteria for listing on the California Register of Historical Resources
(Pub. Res. Code §5024.1, Title 14 CCR, Section 4852) including the following:
(A) Is associated with events that have made a significant contribution to the broad
patterns of California’s history and cultural heritage;
(B) Is associated with the lives of persons important in our past;
(C) Embodies the distinctive characteristics of a type, period, region, or method of
construction, or represents the work of an important creative individual, or possesses
high artistic values; or
(D) Has yielded, or may be likely to yield, information important in prehistory or history.”
Assembly Bill 52
With passage of Assembly Bill 52 the State of California recognized, among other things, that:
“California Native American tribes may have expertise with regard to their tribal history and
practices, which concern the tribal cultural resources with which they are traditionally and
culturally affiliated. Because the California Environmental Quality Act calls for a sufficient degree
of analysis, tribal knowledge about the land and tribal cultural resources at issue should be
included in environmental assessments for projects that may have a significant impact on those
resources.”
AB 52 therefore requires lead agencies to begin consultation with a California Native American
tribe that is traditionally and culturally affiliated with the geographic area prior to the release of a
negative declaration, mitigated negative declaration, or environmental impact report for a
project. When responding to the lead agency, the California Native American tribe shall
designate a lead contact person. California Native American tribes have 30 days to request
consultation regarding possible significant effects that implementation of the proposed project
may have on tribal cultural resources. AB 52 notifications began on January 6, 2016. The
response period concluded on February 8, 2016. A number of responses were received,
however, no previously unknown resources were identified by respondents.
4.4.3.2 City of San Luis Obispo Regulations
The City of San Luis Obispo General Plan, Conservation and Open Space Element (2006)
includes a number of policies intended to preserve cultural resources. These polices include:
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3.5.4. Archaeologically sensitive areas. Development within an archaeologically sensitive area
shall require a preliminary site survey by a qualified archaeologist knowledgeable in Native
American cultures, prior to a determination of the potential environmental impacts of the project.
3.5.5. Archaeological resources present. Where a preliminary site survey finds substantial
archaeological resources, before permitting construction, the City shall require a mitigation plan
to protect the resources. Possible mitigation measures include: presence of a qualified
professional during initial grading or trenching; project redesign; covering with a layer of fill;
excavation, removal and curation in an appropriate facility under the direction of a qualified
professional.
3.5.6. Qualified archaeologist present. Where substantial archaeological resources are
discovered during construction or grading activities, all such activities in the immediate area of
the find shall cease until a qualified archaeologist knowledgeable in Native American cultures
can determine the significance of the resource and recommend alternative mitigation measures.
3.5.7. Native American participation. Native American participation shall be included in the City's
guidelines for resource assessment and impact mitigation. Native American representatives
should be present during archaeological excavation and during construction in an area likely to
contain cultural resources. The Native American community shall be consulted as knowledge of
cultural resources expands and as the City considers updates or significant changes to its
General Plan.
4.4.4 Significance Criteria
Appendix G of the CEQA Guidelines provides guidance in determining a project's impact on
cultural resources. This guidance has been used to develop the significance criteria for cultural
resources. Specifically, the project would have a significant impact on cultural resources if:
1. The project causes a substantial adverse change in the significance of an historical
resource. This would include physical demolition, destruction, relocation, or alteration of
the resource or its immediate surroundings such that the significance of an historical
resource would be materially impaired;
2. The project causes a substantial adverse change in the significance of an archaeological
resource;
3. If the project directly or indirectly destroys a unique paleontological resource or site or
unique geologic feature; or
4. If the project disturbs any human remains, including those interred outside of formal
cemeteries.
The project will disturb recent alluvium deposits and therefore no paleontological resources
would be impacted. Further, there are no impacts expected to human remains. The section that
follows considers historic and prehistoric resources.
4.4.5 Impacts and Mitigation Measures
This section describes potential impacts and is organized based on the significance criteria #1
and #2 outlined above.
4.4.6 The project causes a substantial adverse change in the significance of an
historical resource
The potential for encountering buried historical deposits is high throughout the project area, but
especially at the Marsh Street terrace. Evaluation of other projects in the vicinity have yielded
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buried historical trash dumps along the creek. The discussion of impacts and mitigation
measures that follows is focused on historical resources and organized by project component,
or sub-component, as applicable. The place names in the ASR and the current project
description vary at times, so names are cross-referenced in parentheses, as necessary.
Flow Return (Marsh Street Terrace)
The Flow Return component is the most sensitive area for buried historical resources. The
project would include excavating the majority of the northern half of the parcel to construct the
flow return. Excavation would occur from the eastern edge of the parcel to approximately the
bank of the creek, where additional grading for a creek bench would occur.
The location is currently undeveloped; however, Sanborn Fire Insurance maps show that this
was a residential neighborhood on the fringe of the railway district beginning with the first
structure dating to at least 1891. Over the next 100 years, the following residences and
businesses existed on these lots: residences (1891, 1909, 1926, 1930’s-1940’s), automobile
service station, auto repair shop (1926, on “pilings over the creek”), stone cutting business
(1931), leather shop, possible restaurant, beer warehouse, laundry facility, auto repair,
motorcycle repair shop, and a plumbing business. Further, a structure can be seen in this
location on the 1877 “Birds Eye View of San Luis Obispo” (refer to Figure CR-1) that was
demolished by the time the 1891 Sanborn map was drawn.
At the turn of the century, trash pits and privies would have been located away from the homes,
toward the creek banks. Significant intact, but buried, deposits may be encountered during
construction.
Pinch Point (Madonna Bench)
This portion of the project would involve the excavation of the creek banks on both sides of the
creek, up to approximately 240 feet on the western side. When the ASR was prepared, the
project included construction of a bench, approximately 7 feet in depth, on the western creek
bank, only, although it would span from the Marsh Street Bridge to the Bianchi Lane Bridge,
which is approximately 640 feet. The area close to Bianchi Lane has been determined to be
sensitive in the past for historic resources.
Bianchi Bypass (Bianchi Lane Terrace)
This portion of the project is located on the west side of the creek and would involve
construction of the bypass channel approximately 6 to 8 feet deep from the Bianchi Lane Bridge
south approximately 800 feet. The Bianchi Bypass includes two City-owned open space parcels
that are located between Highway 101 and the creek. No structures are currently on the
property. Sanborn maps did not cover this area. Historical aerials from 1937 show this area as
undeveloped. The 1949 aerial shows grading or fill at this location, likely related to the
construction of Highway 101. Surface survey revealed only modern trash related to homeless
encampments along the creek bank.
Bianchi Lane Bridge
The Bianchi Lane Bridge is a single-span steel bridge with a date stamp of 1905. This bridge
was originally a railroad bridge near Elks Lane that was converted to an automobile bridge and
moved to its current location around 1940. It was evaluated by Caltrans for National Register
significance and found to be ineligible.
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South Street Bench
This portion of the project would involve the construction of a bench, approximately 8 feet deep
and 200 feet long, located on a narrow strip of City-owned open space property that is located
between the creek and the Hayward Lumber Yard at the western end of South Street. This
specific area is not covered by the Sanborn maps, but areas immediately to the east are. A
small dwelling was located on the north side of South Street approximately 100 meters east of
San Luis Obispo Creek in 1888. Trash dumps associated with this structure may be found
buried closer to the creek. The commercial property immediately adjacent to this proposed
bench was surveyed in 1998 and did not show any surface indications of cultural resources. A
buried historical trash dump was previously discovered at the end of South Street just about 10
meters south of this bench location.
South Street Bypass
The South Street Bypass would be approximately 10 feet deep and 600 feet long, parallel to
and west of the existing creek. The South Street Bypass is situated on City-owned open space
property located between Highway 101 and the creek. The west side of the creek is generally
less sensitive than the east, where the commercial development and railway yard were located.
There is no evidence from the historical aerial photographs dating back to 1937 that this parcel
was ever developed. This area appears to be heavily impacted (and possibly filled) from the
construction of Highway 101.
Impact CR-1 Excavation of the project components, including, but not limited to the Flow
Return, the Pinch Point, and the Bypass channels, have the potential to impact
buried historical resources.
CR-mm-1 Prior to construction, a detailed excavation and monitoring plan shall be prepared
and implemented by a qualified historical archaeologist. The monitoring plan
should specify the following:
1. A description of preconstruction exploratory excavations at the Flow Return;
2. A description of how and where the monitoring will occur;
3. Description of monitoring intensity at different project locations;
4. A description of the resources anticipated to be discovered;
5. A description of the circumstances under which construction will be halted;
6. Description of the procedures to be followed in the event significant resources
are found;
7. Personnel involved in monitoring activities; and
8. Arrangements for curation and a description of those materials that would
qualify for curation.
9. Procedures to be implemented in the event there is an unanticipated
historical or prehistoric discovered within the project area during construction
to ensure compliance with State and local code.
Residual Impact. After implementation of MMCR-1, residual impacts to cultural and
paleontological resources would be less than significant.
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4.4.7 The project causes a substantial adverse change in the significance of an
archaeological resource.
No prehistoric archaeological sites were discovered in the project’s APE. Furthermore, the
project excavation areas are located within the creek banks that would have been active
floodplain (and therefore, unattractive for human settlement) until channelization by urban uses.
The potential for prehistoric buried resources is very low in this area. No impacts will result from
the project and no measures other than those already required by City code are required.
4.4.8 Cumulative Impacts
Implementation of the proposed project, combined with other reasonably foreseeable projects
within the creek watershed could result in the cumulative discovery and/or disturbance of
cultural resources. Redevelopment of the Mid-Higuera corridor could impact cultural resources.
The proposed project would not impact any known prehistoric resources and therefore would
not contribute to cumulative impacts to prehistoric resources.
The project would potentially impact historic resources, although mitigation measures have
been recommended to reduce project-specific impacts to less than significant levels. This, along
with the cultural resources avoidance and minimization measures in the WMP, the Mid-Higuera
Enhancement Plan, and in the City’s General Plan and codes which would be applied to future
projects, ensure that the proposed project would have a less than significant cumulative
contribution to cultural resources.
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4.5 Hazards and Hazardous Materials
This sections describes the hazards and hazardous materials conditions that may affect or be
affected by the project. The information in this section summarizes three reports prepared for
the project, including the Phase I Environmental Site Assessment and Preliminary Phase II
Subsurface Assessment Activities for Properties Associated with Proposed Mid-Higuera By-
Pass Project (Padre 2010), and the Report of Findings of the Supplemental Soil Assessment
Activities for the Mid-Higuera Bypass Project (Padre 2016). These documents are available for
review in their entirety from the District.
4.5.1 Existing Conditions
4.5.1.1 Phase I Environmental Site Assessment Results
The objective of the Phase I Environmental Site Assessment (Phase I) prepared for the project
was to
“…evaluate whether current or previous land use at or adjacent to the Project Site may have
involved, or resulted in the use, storage, disposal, treatment, and/or release of hazardous
substances to the environment, resulting in the determination of a Recognized Environmental
Condition (REC) associated with the various the Project Site properties.”
A REC is defined by ASTM E-1527-05 as the presence or likely presence of any hazardous
substance or petroleum products on a property under conditions that indicate an existing
release, a past release, or a material threat of release of any hazardous substances or
petroleum products into structures on the property or into ground, groundwater, or surface water
of the property.
After a review of available resources, the following conclusions were made regarding the
potential for the presence of hazardous materials within the project area. In some cases,
different terms were used for the project components. In these cases, the current name is
provided first and the name used in the technical report is included in parentheses.
Flow Return (Marsh Street Terrace)
A former gasoline service station was located on a portion of this component from the 1950s to
the 1990s. The property had three underground storage tanks (USTs), which were removed in
the 1980s; however, supporting documentation was not available regarding the soil conditions
surrounding the USTs upon removal. Additionally, other portions of this component (between
316 and 350 Higuera Street) have historically been occupied by auto repair facilities, a possible
dry cleaner/laundry facility, and a stone cutting business (circa 1920s). Off-site uses that could
affect this component include a former PG&E substation with a listed open Leaking UST case,
and a former manufactured gas plant with continuing investigation/remediation pending. Both of
these uses were located immediately east of the Flow Return, across Higuera Street.
Madonna Bench
This bench would be excavated on the eastern side of the Madonna Construction Yard property,
between the channel and the structures. The property has maintained up to four USTs through
the early 2000s, and a closed LUST case was documented for the properly. Additionally, the
aboveground storage of numerous types of chemicals and petroleum products has been
documented, and the property was generally used as a heavy equipment construction and
maintenance yard circa 1950s to the present.
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Bianchi Bypass and Bridge (Bianchi Lane Terrace)
Based on a review of aerial photographs, it appears that undocumented fill material may have
been placed in the area of the proposed bypass. Additionally, the Bianchi Bridge and Bypass
area appears to have been used as a heavy construction equipment storage area associated
with the Madonna Construction Yard.
South Street Bypass and Bench
The proposed bench between the Bianchi Bypass and South Street Bypass is located
immediately adjacent to a listed UST and closed LUST case (34 South Street). The LUST was
removed, impacted soil was remediated, and the LUST case was closed with the SLO Fire
Department. Additionally, this property was documented to have been a laundry facility or
uniform care service facility prior to the 1990s. The northern-most area of the bench South
Street Bench is also located adjacent to a property known to have maintained an “oil shack” with
shallow soil documented to contain petroleum hydrocarbons exceeding SLO Fire Department
cleanup goals. However, the oil shack and the shallow soil in the area were reportedly removed
approximately 15 to 20 years ago. The Phase I did not identify any potentially hazardous
conditions associated with the properties included as part of the South Street Bypass.
4.5.1.2 Preliminary Phase II Environmental Site Assessment Results
In an effort to better characterize the potential hazardous materials issues in the project area
identified in the Phase I, the County proceeded with preliminary Phase II (subsurface sampling)
hazardous materials assessment. The preliminary Phase II work included the development of
the nine direct-push drill holes, seven hand augured drill holes, and the collection of several soil
samples from the surface/shallow soil zone. The results of the preliminary Phase II work are
summarized below:
Flow Return
A total of 11 drill holes were advanced in this area to assess subsurface soils for the presence
of petroleum hydrocarbons associated with a former gasoline service station and those that may
presence or evidence of impacts that may be associated with past industrial activities, auto
repair shops, and possible laundry/dry cleaning facility. Based on the analytical results and field
observations, there was no indication of fuel or waste oil releases to the subsurface soil from the
former gasoline station USTs or associated product piping.
At one drill hole on the southern portion of this component (HA -3), an approximately 1-foot layer
of black sandy soil with ash or slag and brick fragments was encountered beginning at a depth
of 2 feet below surface at drill hole location HA-3. Soil samples collected indicated
concentrations of PAHs exceeding the Residential RSLs and TPH exceeding SLOFD cleanup
goals. The vertical extent of PAH and TPH-containing soil within drill hole HA-3 is estimated to
approximately 3 feet below surface. The lateral extent of the ash/slag layer could not be
evaluated during the assessment.
Madonna Bench
Four shallow zone (within upper 1-foot) soil samples were collected and chemically analyzed to
evaluate for the presence of petroleum hydrocarbons and California-regulated metals
associated with historical chemical use and storage and the maintenance of construction
equipment at this area of the project site. TPH was indicated in all four samples at
concentrations exceeding the SLOFD action level of 100 mg/kg. Additionally, soluble lead was
indicated at a concentration exceeding the STLC, which renders the soil as California
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Hazardous for disposal criteria should the soil be disposed at a landfill. The vertical and lateral
extents of TPH and STLC lead containing soil were not characterized.
Bianchi Bypass and Bridge (Bianchi Lane Terrace)
Based on the field observations and analytical results from five collected soil samples, TPH was
indicated at a concentration exceeding the SLOFD action level in one sample collected at a
depth of two feet below surface. The sole, shallow zone TPH concentration detection may have
been a result of asphalt debris associated with an old, weathered asphalt road observed within
the area assessed.
South Street Bench
Two drill holes were advanced within this area of the project site. Based on the field
observations, there was no indication of TPH-containing soil at the drill hole locations. A third
drill hole originally proposed was not advanced because upon further review, the proposed the
bench area would not extend into the area of the former “oil shack” on the adjacent property to
the north.
Lead and Naturally Occurring Asbestos Sampling
Surface soil samples were collected near Hwy 101 on the northern-most area of the South
Street Bypass and within the Bianchi Lane Bypass nearest Hwy 101. The samples were
chemically analyzed for lead and naturally occurring asbestos. The lead concentrations did not
exceed the Residential RSL and asbestos was not detected in the two samples collected.
4.5.1.3 Subsequent Phase II Environmental Site Assessment Results
In April 2016 a subsequent Phase II environmental assessment was performed. The intent of
the subsequent assessment was to further characterize the lateral and vertical extent of
chemicals of potential concern (COPC) in two project areas, the Flow Return Area and the north
end of the Bianchi Bypass. A total of 15 drill holes were made and soil samples collected for
testing at appropriate depths. Forty-three soil samples were collected.
Flow Return Area
Subsurface soil encountered in this area primarily consisted of fill material including large
granitic gravel, concrete debris, brick, and asphaltic clasts contained within a sandy soil. The
large gravel and concrete debris made it impossible to advance the manual hand auger drill
below one to two feet at the locations of several drill holes.
COPCs identified at the Flow Return Area include lead and several PAH constituents within the
upper three to five feet of soil and laterally distributed across most of the area, including the
proposed bench area.
Lead, at concentrations in excess of the ESL, is located primarily within the northwestern area
of the proposed flow return and the northern portion of the proposed bench, with the maximum
vertical extent estimated at a depth of approximately four feet at both areas. Lead, at
concentrations in excess of the TTLC and/or the STLC (California-hazardous), was identified
within the northwestern area of the proposed flow return and northeastern area of the proposed
bench.
PAH constituents exceeding the ESLs are generally widespread throughout both the flow return
and bench areas. The estimated average depth of the contamination is approximately three feet
at both the flow return and bench areas. However, the vertical extent was not defined at the
location of eight drill holes advanced at both the flow return and bench areas due to concrete
and/or large gravel encountered during the course of the hand-auger.
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Based on the preliminary and subject supplemental assessment data, the report concluded that
approximately 1,810 cubic yards of soil are impacted with PAH constituents and lead
concentrations exceeding their respective ESLs. Of the estimated 1,810 cubic yards,
approximately 460 cubic yards of soil are additionally impacted with lead exceeding the TTLC
and/or STLC values and would be classified as California-hazardous waste for disposal
purposes.
Bianchi Bypass/Bridge
A total of eight soil samples were chemically analyzed for the presence of TPH (diesel fuel and
motor oil ranges) from this area. None of the soil samples with reportable concentrations of TPH
(both diesel fuel and motor oil ranges) exceeded the respective ESLs. A total of eight soil
samples collected were chemically analyzed for the presence of California-regulated metals.
None of the eight soil samples chemically analyzed for California-regulated metals were
indicated in excess of their respective established TTLC concentration. A total of seven soil
samples were further chemically analyzed by STLC and/or TCLP methods for soluble chromium
and/or nickel. Soluble chromium and nickel concentrations did not exceed their respective STLC
values.
4.5.2 Regulatory Setting
Hazards and hazardous material management is subject to multiple laws, policies, and
regulations at all levels of government. The agencies responsible for enforcing applicable laws
and regulations develop and enforce standards for the handling and cleanup of specific
materials determined to pose a risk to human health or the environment. The enforcing agency
at the local level for the proposed project area is San Luis Obispo County Health Agency,
Division of Environmental Health. Enforcement agencies at the State level include two branches
of the California Environmental Protection Agency (CalEPA), the Department of Toxic
Substances Control (DTSC), and the RWQCB. The Federal enforcement agency is the EPA. A
description of agency involvement in management of hazardous materials is provided below.
4.5.2.1 Federal Policies and Regulations
The EPA is the Federal agency responsible for enforcement and implementation of federal laws
and regulations pertaining to hazardous materials; in addition, the EPA provides oversight and
supervision for some site investigation/remediation projects. For disposal of certain hazardous
wastes, the EPA has developed land disposal restrictions and treatment standards. Legislation
includes the Resources Conservation and Recovery Act of 1986 (RCRA), the Superfund
Amendments and Reauthorization Act of 1986 (SARA), and the Comprehensive Environmental
Response, Compensation, and Liability Act of 1980 (CERCLA). The Federal regulations are
primarily codified in Title 40 of the Code of Federal Regulations (CFR). These laws and
regulations include specific requirements for facilities that handle, generate, use, store, treat,
transport, and/or dispose of hazardous materials, as well as for investigation and cleanup of
contaminated property.
4.5.2.2 State Policies and Regulations
Regional Water Quality Control Board
The project site is located within the jurisdiction of the Central Coast RWQCB. The RWQCB is
authorized by the California Porter-Cologne Water Quality Act of 1969 (“the Porter-Cologne
Act”), to implement water quality protection laws. When the quality of the groundwater or the
surface waters of the State is threatened, the RWQCB has the authority to require investigations
and remedial actions. In addition, the Central Coast RWQCB is the State regulatory agency that
oversees the local Leaking Underground Fuel Tank (LUFT) program, which was established to
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regulate underground fuel tanks. Under the LUFT program, local implementing agencies are
required to permit, inspect, and oversee monitoring programs to detect leakage of hazardous
materials.
Department of Toxic Substances Control (DTSC)
In California, the DTSC, a branch of CalEPA, works in conjunction with, or in lieu of, the EPA to
enforce and implement specific hazardous materials laws and regulations. California has
enacted its own legislation pertaining to the management of hazardous materials.
California Occupational Safety and Health Agency
Worker health and safety in California is regulated by the Department of Industrial Relations,
Division of Occupational Safety and Health (Cal/OSHA). Cal/OSHA standards and practices for
workers dealing with hazardous materials are contained in Title 8 of the CCR, and include
Division 1, Chapter 4, Subchapter 7 (General Industry Safety Orders) and Section 5192.
Hazardous Waste and Substance Site List (Cortese List)
The Cortese List is a compilation by the State of California Office of Planning and Research of
potential and confirmed hazardous waste and substance sites throughout California. The
Cortese list includes tank leaks compiled by the State Water Resources Control Board
(SWRCB), abandoned hazardous waste sites by the DTSC, California Bond Expenditure Plan
(BEP) and solid waste disposal sites with known migration of hazardous waste. A total of 13
properties within a one half-mile radius of the project were identified on the Cortese list. These
properties are described in the Phase 1 (Padre 2010).
4.5.2.3 Local Policies and Regulations
San Luis Obispo County Air Pollution Control District
The federal and state Clean Air Acts are enforced locally by the San Luis Obispo County Air
Pollution Control District (SLOAPCD). The SLOAPCD regulates potential discharges of criteria
air pollutants (including organic compounds that contribute to ozone formation) and toxic air
contaminants.
San Luis Obispo County Health Agency
Pursuant to State law and local ordinance, the Division of Environmental Health of the San Luis
Obispo County Health Agency conducts inspections to ensure proper handling, storage, and
disposal of hazardous materials and proper remediation of contaminated sites. In addition, the
Hazardous Materials Release Response Plans and Inventory Law of 1985 (Business Plan Act,
[i.e., Chapter 6.95 of Division 20 of the California Health and Safety Code]) requires that any
business that handles or stores hazardous materials prepare a Hazardous Materials Business
Plan. Under this law, businesses are required to submit inventories of on-site hazardous
materials and wastes and the locations where these materials are stored and handled. This
information is collected and certified by San Luis Obispo County Environmental Health
Department for emergency response purposes. There are no cities within San Luis Obispo
County that have adopted and implemented their own hazardous materials programs in lieu of
the County program; however, the City of San Luis Obispo Fire Department is a participating
agency with San Luis Obispo County.
4.5.3 Significance Criteria
Appendix G of the CEQA Guidelines states that a project would normally have a significant
impact if it would create a potential health hazard or involve use, production, or disposal of
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materials that pose a hazard to people, animal, or plant populations in the area affected. For the
purposes of this analysis, the questions to be asked include:
1. Create a significant hazard to the public or the environment through the routine
transport, use, or disposal of hazardous materials;
2. Create a significant hazard to the public or the environment through reasonably
foreseeable upset and accident conditions involving the release of hazardous materials
into the environment;
3. Emit hazardous emissions or handle hazardous or acutely hazardous materials,
substances, or waste within one-quarter mile of an existing or proposed school;
4. Be located on a site which is included on a list of hazardous materials sites compiled
pursuant to Government Code Section 65962.5 and, as a result, would it create a
significant hazard to the public or the environment;
5. For a project located within an airport land use plan or, where such a plan has not been
adopted, within two miles of a public airport or public use airport, would the project result
in a safety hazard for people residing or working in the project area;
6. For a project within the vicinity of a private airstrip, would the project result in a safety
hazard for people residing or working in the project area;
7. Impair implementation of or physically interfere with an adopted emergency response
plan or emergency evacuation plan; or
8. Expose people or structures to a significant risk of loss, injury or death involving wildland
fires, including where wildlands are adjacent to urbanized areas or where residences are
intermixed with wildlands.
As identified in the Initial Study (refer to Appendix A), questions 3 through 8 are not applicable
to the proposed project. The project also does not propose routine transport, use, or disposal of
hazardous materials, and therefore question 1 is not relevant to the following discussion.
4.5.4 Impacts and Mitigation Measures
The following includes a discussion of the relevant significance criteria from Appendix G.
4.5.4.1 Create a significant hazard to the public or the environment through reasonably
foreseeable upset and accident conditions involving the release of hazardous
materials into the environment
Based on the site assessment reports prepared for the project, excavation proposed in the Flow
Return area and at the “Madonna Bench”, which is downstream and on the west side of the
channel, will encounter soils/material that should be treated as a hazardous material.
Constituents in these materials may include elevated levels of lead and petroleum-based
products. It can be assumed that at least approximately 410 cubic yards of material
(approximately 40 truckloads) will need to be hauled to an appropriate disposal facility. During
excavation construction personnel could be exposed to the hazardous materials, or loose soil
could potentially erode or be deposited in the creek channel. In addition, if trucks do not properly
secure the hazardous material, the transport of the soil could potentially expose residents to
hazardous materials during the hauling process.
Given the long history of commercial use in the area, despite the substantial testing that has
occurred, there remains a potential for as yet undiscovered contaminated soil to be encountered
during construction.
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HAZ Impact 1 During excavation of the project components construction personnel and the
local environment may be exposed to hazardous materials that exist in the soils.
Haz-mm-1 Prior to initiation of construction, the District shall submit to the City of San Luis
Obispo Fire Department a Construction Materials Management Plan (CMMP).
The CMMP plan shall be implemented throughout construction. The CMMP shall
at minimum present an overview of the procedures and protocols that will be
utilized during the project to safely and appropriately recover, handle,
characterize, store, transport, and dispose of any contaminated materials
encountered during construction of the project. In the event that hazardous
materials are encountered during excavation activities, the contaminated soil
shall be excavated to the extent necessary to safely construct the project.
Residual Impact. Haz-mm-1 would require that the District prepare a CMMP that would address
the handling of known and potentially encountered hazardous materials. The CMMP would
describe how contaminated materials should be separated from the other materials, what kind
of containment would be required (i.e. tarping, barrels, etc.) and what human safety measures,
such as dust control and handling procedures should be implemented to minimize exposure.
The CMMP would be reviewed by the two local agencies with the responsibility for regulating
hazardous materials. This measure would reduce potential impacts to a less than significant
level. No additional measures are required.
4.5.5 Cumulative Impacts
Potential hazards in this EIR are location-specific to the extent that they may result in significant
impacts on the localized environment, but they are not “cumulative” in the sense normally
applied in CEQA documents. Further, the impacts identified in this section are associated with
relatively short-term construction activities and the ongoing clean-up of contamination and
decommissioning of the Marine Terminal will reduce potential exposure to hazards during
construction. The mitigation measures that have been identified for the proposed project would
apply cumulatively as well. Cumulative impacts would be less than significant. No additional
mitigation is required.
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4.6 Hydrology / Water Quality
This section includes a discussion of local flooding and drainage conditions, and factors
affecting water quality such as erosion and sedimentation. The section draws from previous
analysis of the watershed, including the EIR/EIS and the Project Report Design Review
(Wallace Group, 2014).
4.6.1 Existing Conditions
The overall hydrologic conditions of the San Luis Obispo Creek watershed are described in
detail in the EIR/EIS and Waterway Management Plan (WMP). The project is located entirely
within an area identified as Reach 10. The northern portion of the project corridor is
approximately 500 feet downstream of the confluence of Stenner and San Luis Obispo creeks.
Reach 10 is described in the WMP as follows:
“Reach 10 is a 1.2-km stretch extending from the Madonna Road Bridge upstream to the
confluence with Stenner Creek. This reach was also surveyed in 1997 as part of the Phase I
studies. For 125 meters upstream of the Madonna Road Bridge the steep west bank is being
undercut at the toe, potentially threatening the Highway 101 roadway base fill. Moving
upstream, the outside of the next meander bend is protected by a mixture of rip-rap, gabions
and grouted rock. Upstream of this is a 100-meter stretch of relatively undisturbed channel
before the creek bends back to the east. The outside of this bend, which is protected by sacrete,
runs closely alongside Highway 101. The west bank on the upstream edge of the sacrete is
over-steepened and could result in gradual failure of the sacrete.
The Hayward Lumber yard, which was repaired in 1999 as part of the Phase I program is 180
meters upstream of the sacrete wall. Approximately 50 meters upstream of the Hayward
Lumber is the Bianchi Lane Bridge. On the west bank directly upstream of this bridge, there are
a series of culverts that empty into the creek from the top of the bank. The flows from these
culverts are creating gullies, which will continue to widen and may eventually jeopardize the
bridge foundation. Between the Bianchi Bridge and the Marsh Street Bridge upstream, the
channel is straight with steep moderately vegetated banks. Portions of the west bank in this
200-meter stretch show signs of incipient erosion. Between the Marsh Street Bridge and the
confluence with Stenner Creek, SLO Creek passes under another small bridge and through a
straight stretch of well-vegetated trapezoidal channel. Channel gradient steepens in this area.”
4.6.1.1 Local Flooding and Drainage
San Luis Obispo Creek, between Marsh Street and Madonna Road, has flooded six times in the
last 40-50 years (Questa 2009). The flooding occurs for a number of reasons, including the
creek cross-section is narrow in this area, the floodplain is heavily developed on the eastern
side of the creek and the Marsh Street Bridge and the Bianchi Lane Bridge can act as
constriction points. During flood events the water level in the creek, immediately north of the
Marsh Street Bridge, rises above the top of the creek bank during periods of heavy rain. The
creek water subsequently flows into the adjacent streets, damaging public and private property.
The Mid-Higuera area of San Luis Obispo creek has a large upstream watershed, including the
Stenner Creek and Brizzolara Creek tributaries. A comprehensive watershed model for San Luis
Obispo Creek was developed as part of the WMP. The peak flows derived through the WMP
model are the basis for analysis of the Mid-Higuera project. Peak flows for this section of San
Luis Obispo Creek are summarized in Table HWQ-1.
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Table HWQ-1. San Luis Obispo Creek Peak Flows
Return Interval (year) Runoff Rate (cfs)
10 7,769
25 9,676
100 12,501
Per the WMP, flow in the creek can respond very quickly to short high intensity rainfall bursts,
and floods in the creek tend to be of high magnitude but relatively short duration. Figure HWQ-1
shows the 100-year flood plain in the project area. The floodplain includes nearly the entire
project area and surrounding neighborhoods.
4.6.1.2 Water Quality
The issue of surface water quality is important because of the value of the creek for several
endangered or threatened plant and animal species. The Regional Water Quality Control Board
(RWQCB) has identified multiple beneficial uses for the creek, including present and potential
beneficial uses for municipal supply, agricultural supply, groundwater recharge, recreation,
wildlife habitat, warm and cold fresh water habitat, migration of aquatic organisms, spawning,
reproduction and/or early development of fish, and commercial and sport fishing (City of San
Luis Obispo 2014).
Surface water entering watercourses from undeveloped areas usually travels over vegetative
cover, and erosion and sedimentation is a slow, gradual process. Urbanized areas typically
contain pollutants on the ground surface that are harmful to water quality. These include heavy
metals, hydrocarbons, detergents, fertilizers, and pesticides that originate from vehicle use and
commercial and residential land use activities. For the most part, these pollutants are
associated with sediments that collect on roadways and are flushed into the creek system
during construction or by rainfall. Construction activities can also create erosion and cause
sediment to be transported off-site by surface water runoff. Therefore, water quality depends
mainly on the hydrologic characteristics of the drainage basin, the makeup of the soils in the
watershed, and sources of pollution in the watershed.
The RWQCB has indicated that water quality in the creek is generally good, however, nitrogen
and pathogen levels periodically exceed the Total Maximum Daily Limits (TMDL) established
(RWQCB 2013). The largest contributor to the nitrate issues are agricultural operations
upstream and downstream of the City limits and the City’s Water Recycling Facility. Water
quality monitoring is conducted regularly throughout the watershed, with the nearest location on
Stenner Creek upstream of the project area in downtown San Luis Obispo.
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4.6.1.3 Regulatory Setting
4.6.1.3.1 Federal Regulations
The Clean Water Act
The Clean Water Act (CWA) of 1972 establishes the basic structure for regulating discharges of
pollutants into the waters of the United States and regulates quality standards for surface
waters. Under the CWA, the EPA has implemented many pollution control standards for the
industry along with water quality standards for all contaminants in surface waters. The CWA
made it unlawful to discharge any pollutant from a point source into navigable waters, unless the
EPA authorized a National Pollutant Discharge Elimination System (NPDES) permit.
Federal Emergency Management Agency Flood Zones
The Federal Emergency Management Agency (FEMA) has delineated both special hazard flood
areas and risk premium flood zones applicable to individual communities. The Flood Insurance
Rate Maps help private citizens and insurance companies locate properties in flood risk areas,
aid lending institutions when making loans, and administer floodplain management regulations
in order to mitigate flood damage. The majority of the project site is located within the 100-year
floodplain, and has at least a 1% annual chance floodplain. The proposed project may alter the
existing FEMA flood limit delineations within the project area.
4.6.1.3.2 State Regulations
Under Section 401 of the Clean Water Act, applicants for a federal license or permit such as a
Section 404 Permit must obtain certification from the state (RWQCB), or a waiver of
certification, that the activity would not adversely affect water quality.
In 2013 the Central Coast Region RWQCB adopted Resolution Number R3-2013-0032
regarding Post-Construction Stormwater Management Requirements intended to focus on
discharges that threaten beneficial uses and to require implementation of Best Management
Practices to reduce stormwater pollutant discharges to the maximum extent practicable and
protect water quality and beneficial uses.
4.6.1.3.3 City of San Luis Obispo Regulations
City of San Luis Obispo Engineering Standards. Per the City’s recently prepared Land Use and
Circulation Element Programmatic Environmental Impact Report, current Engineering Standards
for the City include the following requirements:
x All new development or redevelopment shall comply with the criteria and standards set
forth in the Waterways Management Plan – Drainage Design Manual, applicable area
specific plans, and the Post-Construction Stormwater Management Requirements for
Development Projects in the Central Coast Region, adopted by the Central Coast
Regional Water Quality Control Board. Where requirements conflict, the stricter shall
apply.
x Stormwater Control Plan, and Operation and Maintenance Plan are required prior to final
approvals.
x Projects with pollution generating activities and sources must be designed to implement
operation or source control measures consistent with recommendations from the
California Stormwater Quality Association Handbook for New Development and
Redevelopment or equivalent, including: a) Accidental spills or leaks, b) Interior floor
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drains, c) Parking / storage areas and maintenance, d) Indoor and structural pest
control, e) Landscape / outdoor pesticide use, f) Pools, spas, ponds, decorative
fountains and other water features, g) Restaurants, grocery stores, and other food
service operations, h) Refuse areas, i) Industrial processes, j) Outdoor storage of
equipment or materials, k) Vehicle and equipment cleaning, repair, and maintenance, l)
Fuel dispensing areas, m) Loading docks, n) Fire sprinkler test water, o) Drain or wash
water from boiler drain lines, condensate drain lines, rooftop equipment, drainage
sumps, and other sources, p) Unauthorized non-stormwater discharges, and q) Building
and grounds maintenance
x Design should prevent water from contacting work areas, prevent pollutants from coming
in contact with surfaces used by stormwater runoff, or where contact is unavoidable, and
treat stormwater to remove pollutants.
x Operations and maintenance activities required to achieve Source Control are to be
included in the Operation and Maintenance Plan submitted for approvals and recorded
with the property as required by ordinance.
4.6.1.3.4 Waterway Management Program
The WMP, which was developed in 2003 and includes the Stream Maintenance and
Management Program (SMMP) and the Drainage Design Manual (DDM) are used by the City
and County of San Luis Obispo (collectively “Zone 9”) to design flood control, water quality, and
habitat enhancement projects within the San Luis Obispo Creek watershed. These documents
outline both policies and specific measures that guide the design, operation and maintenance of
these improvements. Specifically, recommended bypass channel design is described and
shown in Section 5.3.2 and in Figure 5-4 of the DDM. The proposed project is consistent with
those descriptions and others related to treatment of exotic species and enhancement of
aquatic resources habitat by installing large root wads, for example.
4.6.2 Significance Criteria
Criteria for evaluating the significance of hydrology and water quality impacts included in the
CEQA Guidelines, Appendix G, are directed toward identifying substantial changes in drainage
patterns, drainage volumes, or violations of water quality standards. Impacts would be
considered significant if the proposed project would result in any of the following:
1. Potentially degrade surface or groundwater quality below standards established by the
Regional Water Quality Control Board;
2. Substantially interfere with groundwater recharge;
3. Substantially alter the existing drainage pattern of the area such that substantial erosion
or sedimentation occurs;
4. Substantially alter the existing drainage pattern or substantially increase the rate or
amount of surface runoff in a manner which results in flooding;
5. Create or contribute runoff which would exceed the capacity of stormwater drainage
systems; or
6. Substantially add additional sources of polluted runoff to a water body.
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4.6.3 Impacts and Mitigation Measures
The proposed project will involve the operation of heavy machinery within and adjacent to the
creek channel, require dewatering in multiple locations throughout the project area, and require
substantial grubbing and other vegetation removal. These activities could introduce pollutants
such as petroleum products into surface or groundwater directly or indirectly, and expose soils
to erosion, impacting water quality. Due to the nature of the project, it is not expected to (1)
degrade surface water quality below RWQCB standards; (2) affect groundwater recharge; (3)
increase the amount of rate of surface runoff, or (4) contribute runoff that would exceed the
capacity of stormwater drainage systems; therefore, these criteria are not discussed further.
There is potential for the project to alter drainage patterns, and/or substantially add pollutants to
San Luis Obispo Creek. These potential impacts are described below.
4.6.3.1 Substantially alter the existing drainage pattern of the area such that substantial
erosion or sedimentation occurs.
Development adjacent to or near surface waters is subject to specific design and construction
conditions in order to ensure the project’s stormwater is adequately contained and directed
without adversely affecting downstream locations. Typically, an impact would occur if the
proposed project directed construction runoff or stormwater to areas where downstream
capacity could be exceeded. Because the proposed project would increase stormwater capacity
of the creek, the assessment focuses instead on impacts to water quality which could result
from the use of heavy machinery in and near the creek, grading, vegetation removal, and the
construction of new structures.
Construction activities would significantly impact water quality due to the exposure of large
areas of soil to erosive forces, the need to dewater during construction, and due to the presence
of fuel, oil, and other pollutants on site for construction purposes. Because of the work proposed
within the channel of the creek and the size of the area of disturbance, implementation of the
project will be contingent upon the receipt of permits from the United States Army Corps of
Engineers, Regional Water Quality Control Board, and the California Department of Fish and
Wildlife. Prior to the issuance of those permits, the regulatory agencies will require a number of
project-specific plans to address potential water quality/hydrology impacts. These plans are
described in Chapter 2.0 Project Description and include, but are not limited to: Diversion and
Dewatering Plan, Stormwater Pollution Prevention Plan (SWPPP), Sedimentation and Erosion
Control Plan (ESCP), Spill Prevention Control and Contingency Plan (SPCC), and a Habitat
Mitigation and Monitoring Plan (HMMP). In addition a Caltrans encroachment permit is required,
and Caltrans will have an opportunity to confirm the proposed erosion control plan is adequate
to protect Highway 101.
Implementation of these plans, along with the WMP measures, which are applied to all projects
within the City limits, would reduce impacts to a less than significant level. No additional
mitigation measures are required.
4.6.3.2 Substantially add additional sources of polluted runoff to a water body.
Under existing conditions, during flooding events flood waters will overtop the creek channel
upstream of the Marsh Street Bridge and flow “down” South Higuera Street, eventually re-
entering the channel between Marsh Street and Madonna Road through the storm drains or as
sheet flow through properties between South Higuera Street and the creek. The flood waters
carry debris from upstream as well as pollutants from the surface streets they run across (e.g.
Marsh Street, South Higuera Street, Pacific Street).
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The proposed Flow Return would be constructed to provide a specific point where flood waters
could return to the creek channel, potentially reducing flooding further to the south. Under
existing conditions, flood waters already cross the property and re-enter San Luis Obispo Creek;
however, the Flow Return would potentially concentrate these flows and the associated
pollutants.
HWQ-Impact 1 The Flow Return would potentially concentrate polluted flood water and
discharge it to the creek system with no treatment.
HWQ-mm-1 Prior to construction, to minimize the potential for concentrating pollutants at the
Flow Return where flood waters would re-enter San Luis Obispo Creek, this
component shall be designed to maximize the potential for passive stormwater
treatment.
Residual Impact. Implementation of measure HWQ-mm-1 would reduce potential impacts to
less than significant. No additional measures are required. Given that there is currently no
treatment of these flood waters and the flooding problems along Mid-Higuera, the Flow Return,
along HWQ-mm-1, would potentially have a beneficial impact to flooding and water quality.
Based on preliminary analysis, this mitigation measure would not increase impacts to
jurisdictional areas, biological resources, or cultural resources.
4.6.4 Cumulative Impacts
Typical flooding, hydrology, and water quality impacts resulting from development are related to
an increase in impervious surfaces, increased discharge of stormwater or sediment into a
drainage system, or development within a floodplain which may reduce the floodplain capacity
and affect upstream or downstream land uses. These impacts may contribute cumulatively
along with other projects to result in significant impacts. However, the proposed project is a
construction project designed to increase flood control capacity. No impervious surfaces are
proposed.
Projects that potentially have a direct effect on San Luis Obispo Creek are generally highly
regulated. The projects described above would all require permits from resource agencies
including the CDFW, USACE, and the RWQCB. These agencies ensure that impacts to water
quality and habitat are limited. The proposed project is also subject to regulations by all of these
agencies and therefore would not contribute cumulative impacts to water quality or alterations of
the local hydrologic conditions. Cumulative impacts to Hydrology and Water Quality are less
than significant. No mitigation beyond that already discussed in this EIR is required.
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4.7 Noise
This section describes the existing environment, the potential noise impacts from construction of
the proposed project, and necessary mitigation measures. As described in the initial study in
Appendix A, the project would not generate noise after construction (i.e. operational noise). This
section is based primarily on the Noise Impact Assessment for the Proposed Mid-Higuera
Bypass Project (Ambient, 2016). A copy of that report is available for review at the District.
4.7.1 Existing Conditions
The human response to environmental noise is subjective and varies considerably from
individual to individual. Noise in the community has often been cited as a health problem, not in
terms of actual physiological damage, such as hearing impairment, but in terms of inhibiting
general well-being and contributing to undue stress and annoyance. The health effects of noise
in the community arise from interference with human activities, including sleep, speech,
recreation, and tasks that demand concentration or coordination. Hearing loss can occur at the
highest noise intensity levels. When community noise interferes with human activities or
contributes to stress, public annoyance with the noise source increases. The acceptability of
noise and the threat to public well-being are the basis for land use planning policies preventing
exposure to excessive community noise levels.
Noise-sensitive land uses are generally considered to include those uses where noise exposure
could result in health-related risks to individuals, as well as places where quiet is an essential
element of their intended purpose. Residential dwellings are of primary concern because of the
potential for increased and prolonged exposure of individuals to both interior and exterior noise
levels. Additional land uses such as parks, historic sites, cemeteries, and recreation areas are
also considered sensitive to increases in exterior noise levels. Schools, churches, hotels,
libraries, and other places where low interior noise levels are essential are also considered
noise-sensitive land uses.
The project site is located within and adjacent to San Luis Obispo Creek between the Marsh
Street Bridge and Madonna Road Bridge. The proposed construction area is bordered on the
west by Highway 101 and on the east by Higuera Street and existing development. The
topography in the area is generally flat, with little topographic variation, with the exception of a
small knoll between Highway 101 and the northern half of the South Street Bypass.
The adjacent existing development consists largely of a mix of light industrial, commercial, and
residential land uses. The nearest noise-sensitive land uses include residential dwellings, the
nearest of which are located adjacent to and east of San Luis Obispo Creek along Brook Street,
south of South Street. St. Luke Missionary Baptist Church and Eto Park are also located along
Brook Street, south of South Street. In addition, Mathews Trailer Lodge is located adjacent to
and east of San Luis Obispo Creek, south of Bianchi Lane. These areas are shown on Figure
NS-1.
4.7.2 Regulatory Setting
4.7.2.1 City of San Luis Obispo General Plan
The existing General Plan Noise Element establishes operational standards for siting of new
land uses; however, it contains no policies or programs that address the identification and
mitigation of temporary construction noise generated by land development projects on existing
sensitive receptors.
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4.7.2.2 City of San Luis Obispo Municipal Code
The City’s Noise Control Ordinance, contained in Municipal Code, Chapter 9.12. Section
9.12.050, limits construction and demolition activities that would result in a noise disturbance to
nearby land uses to between the hours of 7:00 a.m. and 7:00 p.m., Monday through Saturday.
Noise-generating construction and demolition activities are prohibited on Sundays and holidays.
The ordinance further states that, where technically and economically feasible, construction
activities shall not exceed specified standards. For areas consisting of mixed residential and
commercial uses, maximum construction-generated noise levels should be limited to 85 dBA
during the daytime hours (7:00 a.m. to 7:00 p.m.) During the nighttime hours, maximum
construction-generated noise levels should be limited to 70 dBA. The City’s noise ordinance
also establishes noise standards for long-term noise exposure.
dBA is an overall frequency-weighted sound level in decibels that approximates the frequency
response of the human ear. For perspective, a gas lawn mower produces approximately 95 dBA
when the user is 3 feet away. Ambient noise levels in commercial areas are approximately 65
dBA, and in rural areas in the evening the dBA could be expected to be approximately 25 dBA.
4.7.3 Significance Criteria
Criteria for evaluating the significance of potential noise impacts are included in the CEQA
Guidelines, Appendix G. Impacts would be considered significant if the proposed project would
result in any of the following:
1. Exposure of persons to or generation of noise levels in excess of standards established
in the local general plan or noise ordinance, or applicable standards of other agencies;
2. Exposure of persons to or generation of excessive groundborne vibration or
groundborne noise levels;
3. A substantial permanent increase in ambient noise levels in the project vicinity above
levels existing without the project;
4. A substantial temporary or periodic increase in ambient noise levels in the project vicinity
above levels existing without the project;
5. For a project located within an airport land use plan or, where such a plan has not been
adopted, within two miles of a public airport or public use airport, would the project
expose people residing or working in the project area to excessive noise levels; or
6. For a project within the vicinity of a private airstrip, would the project expose people
residing or working in the project area to excessive noise levels.
Ground-borne vibration levels would be considered to have a potentially significant impact if
resultant vibration levels at the nearest structures would exceed 0.3 in/sec ppv (peak particle
velocity) for structural damage and 0.2 in/sec ppv for annoyance to building occupants, based
on Caltrans-recommended thresholds.
The proposed project would not result in increased exposure of sensitive land uses to aircraft
noise, nor would the proposed project interfere with airport operations. As a result, evaluation of
long-term exposure to aircraft noise is not discussed further in this report.
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4.7.4 Impacts and Mitigation Measures
4.7.4.1 Exposure of persons to or generation of noise levels in excess of standards
established in the local general plan or noise ordinance, or applicable standards
of other agencies
The existing General Plan Noise Element establishes operational standards for siting of new
land uses; however, it contains no policies or programs that address the identification and
mitigation of temporary construction noise generated by land development projects on existing
sensitive receptors. Implementation of the proposed project would not result in the creation of
new land uses, nor would the project result in the installation of new transportation or non-
transportation noise sources. As a result, the proposed project would not conflict with noise
standards established in the City’s General Plan. This impact would be less than significant.
4.7.4.2 A substantial permanent increase in ambient noise levels in the project vicinity
above levels existing without the project
The proposed project would not result in the installation of any stationary equipment or long-
term operational activities that would generate noise. In addition, for those existing land uses
located nearest Highway 101, the excavation of the new channels and construction of terraces
and benches would not result in changes to the existing topography that would affect existing
noise shielding characteristics of the site. Furthermore, although the proposed project would
result in the removal of some existing vegetation, significant changes in traffic noise exposure at
land uses located nearest Highway 101 would not occur. This impact is considered less than
significant.
4.7.4.3 A substantial temporary or periodic increase in ambient noise levels in the project
vicinity above levels existing without the project?
Construction noise typically occurs intermittently and varies depending upon the nature or
phase of construction (e.g., land clearing, grading, excavation, and paving). Noise generated by
construction equipment, including earth movers, material handlers, and portable generators, can
reach high levels. Although noise ranges are generally similar for all construction phases, the
initial site preparation phase tends to involve the most heavy-duty equipment having a higher
noise-generation potential. Noise levels associated with individual construction equipment likely
required for construction of the proposed project were provided in Table NS-1.
In accordance with the City’s noise control ordinance, construction-generated noise levels would
be considered significant if maximum noise levels would exceed 85 dBA during the daytime
hours (e.g., 7:00 a.m. to 7:00 p.m.) or 60 dBA during the nighttime hours (e.g., 7:00 p.m. to 7:00
a.m.) Construction activities that would result in significant increases in potential sleep
disturbance or activity interference at nearby noise-sensitive land uses would also be
considered to have a potentially significant impact.
Noise levels generated by some of the loudest construction equipment likely to be active on the
proposed project are shown in Table NS-1.
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Table NS-1
Typical Construction Equipment Noise Levels
Equipment dBA at 50 feet
Air Compressor 78
Backhoe 78
Dozer 82
Forklift 85
Grader 85
Truck 77
Based on the noise levels identified in Table NS-1, intermittent noise levels at noise-sensitive
land uses located within approximately 50 feet of the construction site would be approximately
85 dBA or less. Depending on the activities conducted and equipment used, average-hourly
noise levels at these nearest uses would range from approximately 73 dBA to 82 dBA 50 feet.
Haul trucks required for the delivery of construction materials would also result in short-term
detectable increases in traffic noise levels along nearby roadways.
Construction-generated noise levels associated with construction of the proposed project
components would not be anticipated to exceed the City’s instantaneous daytime noise
standard of 85 dBA. However, in the event that construction activities were to occur during the
nighttime hours, resultant noise levels at the property line of the nearest residences would
exceed the City’s noise standards of 60 dBA Lmax. In addition, construction activities occurring
during the more noise-sensitive nighttime hours could result in increased levels of annoyance
and potential sleep disruption to occupants of nearby residential dwelling units. Furthermore,
construction activities occurring in the vicinity of St. Luke Missionary Baptist Church could
interfere with onsite services. Onsite services typically occur on Sundays, as well as, on
Monday and Wednesday nights (Ambient 2016).
NS-Impact 1 Night-time or weekend construction would potentially significantly impact
sensitive receptors in the project area.
NS-mm 1 To reduce potential noise impacts, the following measures shall be implemented
during construction:
x Noise-generating construction activities shall be limited to between the hours of 7:00
a.m. and 7:00 p.m., Monday through Saturday.
x Noise-generating construction activities shall be prohibited on Sundays and holidays.
x Construction equipment shall be properly maintained and equipped with noise-
reduction intake and exhaust mufflers and engine shrouds, in accordance with
manufacturers’ recommendations.
x Equipment engine shrouds shall be closed during equipment operation.
x Lay-down yards and semi-stationary equipment such as pumps or generators shall
be located at the furthest practical distance from noise-sensitive land uses.
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Residual Impact. Implementation of this measure would reduce short-term noise impacts to a
less than significant level. No additional measures are required.
4.7.5 Cumulative Impacts
Because the project would not produce any operational; noise, potential cumulative impacts are
solely limited to short-term construction noise levels. There are no additional major construction
projects included in the cumulative development scenario. Therefore, the project would not
contribute to any cumulative noise impacts. Potential cumulative impacts are less than
significant. No additional measures are required.
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5 Other CEQA Sections
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5.0 Other CEQA-mandated Sections
Section 15126 of the California Environmental Quality Act (CEQA) Guidelines requires
Environmental Impact Reports to include the following topics:
1. significant environmental effects of the proposed project;
2. significant environmental effects which cannot be avoided if the proposed project is
implemented;
3. significant irreversible environmental changes which would be involved in the proposed
project should it be implemented;
4. growth-inducing impact of the proposed project;
5. the mitigation measures proposed to minimize the significant effects; and
6. alternatives to the proposed project.
In addition, CEQA Guidelines requires Lead Agencies to consider the energy impacts of
proposed projects, with an emphasis on avoiding or reducing inefficient, wasteful and
unnecessary consumption of energy. Appendix F of the CEQA Guidelines suggests that
conserving energy would include (1) decreasing overall per capita energy consumption; (2)
decreasing reliance on natural gas and oil; and (3) increasing reliance on renewable energy
sources. This chapter of the EIR considers these “other topics”.
5.1 Section 15126 Topics
Topics 1, 2, and 5 are included in Chapter 4 of this EIR. Topics 3 and 4 are considered below.
Topic 6 is considered in Chapter 6.
5.1.1 Significant Irreversible Environmental Changes Which Would Be Involved in the
Proposed Project Should It Be Implemented
Section 15126.2(c) of the CEQA Guidelines states that use of nonrenewable resources during
the initial and continued phases of a proposed project may be irreversible if a large commitment
of these resources makes their removal, indirect removal, or non-use thereafter unlikely. Non-
renewable resources, such as natural gas, petroleum products, asphalt, petrochemical
construction materials, steel, copper and other metals, and sand and gravel are considered to
be commodities which are available in a finite supply. The processes that created these
resources occur over a long period of time. Therefore, the replacement of these resources
wouldn’t occur over the life of the project. To varying degrees, the aforementioned materials are
all readily available and some materials, such as asphalt, sand and gravel, are abundant. Other
commodities, such as metals, natural gas, and petroleum products, are also readily available,
but they are finite in supply given the length of time required by the natural process to create
them. The demand for all such resources is expected to increase regardless of whether or not
the project is developed. Increases in population will directly result in the need for resources.
Resources necessary for implementation of the proposed project include gravel and rock for the
bypass channel transition areas. The majority of the resources would be used during short-term
project construction. The long-term commitment of resources associated with maintenance of
the project is limited.
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5 Other CEQA Sections
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Mid-Higuera Bypass Project FSEIR
5.1.2 Growth-Inducing Impacts
CEQA Guidelines Section 15126.2 (d) state that in the preparation of an EIR, growth inducing
impacts that need to be addressed are ones that “…foster economic or population growth, or
the construction of additional housing…remove obstacles to population growth…encourage and
facilitate other activities that could significantly affect the environment either individually or
cumulatively”. An example given is the expansion of a wastewater treatment plant allowing for
increased construction in service areas. Based on this direction the proposed project was
evaluated in order to determine if any part of the project demonstrates the potential for growth
inducing impacts. Development in the area is currently constrained by the flood potential,
required creek setbacks, existing development which includes a mobile home park and a large
lumber/hardware supply yard.
The project would reduce the recurrence interval for flooding along the section of Higuera Street
between Marsh Street and Madonna Road. This improvement could potentially be considered
as reducing an obstacle to growth as it would make it more attractive to intensify development
along the Higuera Street corridor. However, potential growth-inducing impacts are less than
significant because:
1. the majority of the parcels adjacent to the project corridor are already developed;
2. each parcel would still be located within the 100-year flood plain even with
implementation of the project;
3. development proposed in the future would be subject to City-mandated creek setbacks
which didn’t exist when the parcels were first developed; and
4. the only relatively large and vacant parcels within the project corridor will be used for the
bypass channels and the Flow Return, and therefore would not be developed.
5.2 Appendix F: Energy Conservation
The energy used for the project is primarily related to the initial construction activities.
Construction vehicles would use non-renewable resources such as diesel fuel and other
petroleum products during construction. Once the project is constructed, “operation” of the
project would be limited to periodic (i.e. every 5-10 years, possibly) sediment management in
the bypass channels. This would involve periodically removing sediment from the channels in
the event that it did accumulate.
There are currently no feasible alternatives to the use of heavy diesel-powered equipment for
the construction activities. The project will be required to comply with the mitigation measures in
the Air Quality/Greenhouse Gas section of this SEIR. Those measures encourage fuel
conservation as a method of reducing emissions. Further, due to its location within urban San
Luis Obispo, it is expected that the length of the trips made by construction personnel, the
heavy equipment, and trucks hauling spoils offsite would be relatively short when compared to
projects which occur in more rural areas. Because the operation of the project is limited, there
are no feasible energy conservation measures to be implemented.
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6.0 Alternatives Analysis
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Mid-Higuera Bypass Project FSEIR
6.0 Alternatives Analysis
6.1 Introduction
Section 15126.6 (a) of CEQA, requires an EIR to:
“describe a reasonable range of alternatives to a project, or to the location of a project, which
could feasibly attain most of the basic objectives of the project but would avoid or substantially
lessen any of the significant effects of the project, and evaluate the comparative merits of the
alternatives.”
The primary objectives of the project are to increase the flood-carrying capacity (up to a 25-year
storm in some locations) of San Luis Obispo Creek from Marsh Street to Madonna Road, while
enhancing and protecting water quality as well as special-status species habitat within the
project area.
Significant effects of the project are primarily construction-related and short-term. No significant
and unavoidable (Class I) impacts were identified. This chapter includes a qualitative
assessment of various alternatives, which are summarized in Table 6.1.
6.2 Alternative Evaluation
The EIR/EIS prepared for the WMP includes a robust discussion of watershed-wide alternatives
to the program components included in the WMP, and specific alternatives to the Mid-Higuera
Bypass project. Alternatives that were considered but determined to be infeasible by the Zone 9
Advisory Committee during the WMP process included:
1. Buried Bypass Culvert – This alternative includes constructing a buried bypass culvert
around downtown that would run under Pacific Street or down Meadow Creek.
2. Floodwalls – Includes the construction of floodwalls along the east bank of San Luis
Obispo Creek from approximately Nipomo Street to Madonna Road
3. Significant Channel Enlargement – Involves significantly widening the channel of SLO
Creek between Marsh and Madonna Road to provide 50-year flood capacity.
4. Flood Detention Basins – Requires construction of flood detention basins in upper
Stenner Creek, and upper San Luis Obispo Creek above Reservoir Canyon Road
The EIR/EIS concluded that stream management and maintenance was a key component for
management of the watershed and therefore that component was removed from consideration.
For more information on these and all of the alternatives previously considered, refer to the
WMP EIR/EIS.
Despite the fact that the EIR/EIS considered a reasonable range of alternatives to the Mid-
Higuera Bypass project specifically, the SEIR includes an additional discussion of alternatives in
an attempt to reduce the severity of the short-term construction-related impacts identified.
These alternatives include:
1. Land Purchase/Business Relocation - Purchasing the properties along Higuera Street
most vulnerable to flooding, thereby reducing the flood risk;
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6.0 Alternatives Analysis
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Mid-Higuera Bypass Project FSEIR
2. Marsh Street Bridge Replacement - Reconstructing the Marsh Street Bridge and
Highway 101 interchange;
3. No Project Alternative – This alternative is required by CEQA, and in this case would
include periodic maintenance of the creek reach, including the vegetation and sediment
management that is already periodically performed by the County; and
4. Phased Project – Phasing construction over multiple years to reduce short-term
construction-related impacts to noise, air quality and traffic, as well as to minimize
disturbance to biological resources within the creek channel in any single year.
6.3 Land Purchase/Business Relocation
This alternative would mitigate the flooding impacts by reducing the number of structures,
businesses, and residents that could be exposed to flooding. The City would purchase the
properties and demolish structures, recreating a “floodplain” adjacent to Higuera Street. This
alternative is likely economically infeasible due to the exorbitant costs related to purchasing the
properties in question. Further, it would reduce the area available for commercial use in the City
of San Luis Obispo, potentially increasing the demand for greenfield commercial development
on the edges of town. For that reason, this alternative is inconsistent with the City’s General
Plan policies. Due to its financial infeasibility and inconsistencies with the General Plan and Mid-
Higuera Enhancement Plan, this alternative is not considered further.
6.4 Marsh Street Bridge Replacement
The Marsh Street Bridge over San Luis Creek includes the intersection of Marsh Street with the
Highway 101 onramp and off-ramp. The bridge has been identified as a major constriction for
San Luis Obispo Creek, and its current design allows for the development of large sandbars at
its upstream end. Due to the street configuration in this area, this alternative would likely involve
the reconstruction of the on and off-ramps, as well as adjacent portions of Marsh Street and
Higuera Street. In addition to construction costs this alternative would require the purchase of
private property adjacent to the roads. Further, the level of review and coordination with
Caltrans would require engineering and environmental studies that could take 10 years or more
to accomplish given that the project isn’t “programmed” into any current trans portation planning
documents. Due to these issues, it can be reasonably determined that this alternative is
speculative and infeasible.
6.5 No Project Alternative
The No Project Alternative would include the City performing periodic maintenance of the
vegetation and sediment that accumulates within the channel – particularly that which collects
within the Marsh Street bridge barrels. Depending on the extent of the maintenance activities
and the hydrologic conditions, which vary from year, this alternative would provide additional
flood protection for short periods (generally less than 5 years based on recent City experience).
Due to the limited width of the channel and the constrictions at the Marsh Street Bridge and
Bianchi Lane Bridge, under this alternative only modest, temporary increases in flood capacity
could be achieved. This alternative would reduce short-term construction-related impacts to
biological resources, air quality, and noise. This alternative would not meet the project
objectives nor result in long-term beneficial impacts to biological resources - reduction of
invasive species and improved habitat features for aquatic species - that are anticipated under
the proposed project.
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6.0 Alternatives Analysis
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Mid-Higuera Bypass Project FSEIR
6.5.1 Phased Project Alternative
An alternative that would potentially reduce the short-term construction impacts resulting from
the project is the Phased Project Alternative. This alternative would split the project into three
phases of roughly equal length. For example, Phase 1 would include the project components
from Madonna Road upstream to the downstream end of the Bianchi Bypass. Phase 2 would
include the Bianchi Bypass and Bridge. Phase 3 would include the Pinch Point, Flow Return and
Marsh Street Bridge components. Each of these phases would covers approximately a 1,000
foot-long stretch of the creek. A 3-phase project would potentially result in the following impact
reductions:
x Annual emissions from construction activities would potentially reduce by approximately
one-third in any given year; however, cumulatively emissions would equal those
resulting from a single phase project.
x Assuming South Phase truck traffic would use the Madonna Road/Highway 101 ramps
and the North Phase truck traffic would use the Marsh Street/Highway 101 ramps for the
northern half of the project, short-term noise and traffic impacts would potentially be
limited to one portion of Higuera Street per year.
x Tree removal would be reduced in any given year, and revegetation of disturbed areas
could begin before the entire project area is disturbed. In other words, revegetation
started after the conclusion of Phase 1 would already have two years of growth by the
time that Phase 3 was completed and ready to be revegetated.
x The length of the creek segments to be dewatered would be reduced by one-third in any
given year, potentially reducing short-term, direct impacts to aquatic species and water
quality.
In regards to biological resources, the potential of this alternative to reduce impacts are limited
because while the alternative may reduce the total area of disturbance in a single year, the
construction within one phase could still affect the other corridor. For example, with this
alternative there would be multiple years of staging; some overlap in the phases to allow for the
finished grading, dewatering and revegetation efforts; and the Bianchi Lane Bridge may provide
access to the South phase even though it is part of the North Phase project. In that sense,
resources in one phase that are not static and may be sensitive to adjacent disturbance, such
as nesting birds and aquatic wildlife, may be impacted by construction in both phases.
6.6 Environmentally Superior Alternative
As proposed, the project would not result in any significant and unavoidable impacts; therefore,
any alternative that is environmentally superior would be one that potentially avoids impacts or
substantially lessen those impacts which would be less than significant with mitigation (Class II).
As described above and shown in Table 6.1, the Phased project would potentially spread the
impacts over a longer period and therefore reduce the severity of the impacts in any given year.
However, due to the relatively short length of the corridor and proximity of the operations to the
creek channel, in regards to biological resources, it may be better for the impacts to be focused
in as short a period as possible. The benefits of staging the project over three years do not
appear to present a superior alternative to the proposed project. Therefore, the proposed project
with all mitigations applied may be the environmentally superior alternative, or at least the
environmentally equivalent alternative.
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6.0 Alternatives Analysis 6-4 Mid-Higuera Bypass Project FSEIR Table 6.1 Alternatives Analysis Resource Area Alternatives Comparison Proposed Project No Project Marsh St Bridge Replacement Phased Project Aesthetic Resources Class II Class III – no change from existing conditions Class II – assumes new interchange would require aesthetic resources mitigation/design per Caltrans and City Class II – No change from proposed project Air Quality Class II Class III – less than significant impacts from small sediment removal projects Class I/II – alternative requires significant levels of demolition, grading, concrete and asphalt work. Project would result in emissions rates greater than the proposed project. Class II – reduced annual construction emissions, but similar cumulative emissions to the proposed project Biological Resources Class II Class II – mitigation is typically required by permitting agencies for sediment removal projects Class II – biological resource mitigation required for impacts to the creek below the Marsh Street Bridge. Class II – No overall change to impacts, although the impact to the creek corridor may be less intensive in any given year Cultural Resources Class II Class III – disturbance is generally limited to sediments in the channel and the creek banks where resources are unlikely to exist Class II – no known pre-historic resources; historic resources known in the area; impacts similar to proposed project Class II – No change from proposed project Hazards/ Hazardous Materials Class II Class II – subsurface hazardous materials would not be encountered; however, contaminated soils within the project corridor would remain and potentially leach into the creek. Class II – potential hazardous materials exist subsurface due to long-term use of the area; impacts similar to the proposed project Class II – No change from proposed project Hydrology/Water Quality Class II Class III –flooding continues at current rates Class II – potential impacts similar to the proposed project – erosion control, revegetation, etc plans required Class II – No overall change to impacts, although the potential for erosion and sedimentation impacts to the creek corridor would be less intensive in any given year Noise Class II Class III – no change from current conditions; minor construction-related noise related to sediment removal projects Class I-II – Due to the level of construction required and possible detours onto local roads, noise impacts would be greater than the proposed project. Class II – No change from proposed project Feasibility Feasible Feasible Infeasible within next 10 years due to programming timelines, studies, funding mechanisms Feasible Meets Project Objectives? Yes No Partially - will not improve habitat throughout the corridor Yes Page 123 of 669
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7 References and Preparers
7-1
Mid-Higuera Bypass Project FSEIR
7.0 References and Preparers
7.1.1 References
Ambient Air Quality and Noise Consulting, Air Quality and Greenhouse Gas Impact Assessment
for the Proposed Mid-Higuera Bypass Project. April 2016.
Ambient Air Quality and Noise Consulting, Noise Impact Assessment for the Proposed Mid-
Higuera Bypass Project. April 2016.
City of San Luis Obispo, General Plan Land Use and Circulation Element Update Program
Environmental Impact Report. September 2014.
City of San Luis Obispo, Mid-Higuera Street Enhancement Plan. March 2001.
City of San Luis Obispo, San Luis Obispo Creek Waterway Management Plan Programmatic
Environmental Impact Report / Environmental Impact Statement. October 2003.
City of San Luis Obispo, San Luis Obispo Creek Waterway Management Plan - Volumes I, II,
and III. March 2003.
County of San Luis Obispo, Archaeological Survey Report Mid-Higuera Bypass Project Flood
Control District Zone 9 San Luis Obispo, San Luis Obispo County. January 2011.
County of San Luis Obispo, Habitat Assessment for the Mid-Higuera Bypass Project;
455R277627. October 2010.
Padre Associates, Phase I Environmental Site Assessment and Preliminary Phase II
Subsurface Assessment Activities for Properties Associated with Proposed Mid-Higuera Bypass
Project. September 2010.
Padre Associates, Report Of Findings Supplemental Soil Assessment Activities Mid-Higuera
Bypass / Flood Control Project. June 2016.
Padre Associates, Tree Survey and Identification of Ordinary High Water Mark within San Luis
Obispo Creek. February 2012.
Padre Associates, Tree Survey and Identification of Ordinary High Water Mark within San Luis
Obispo Creek. November 2013.
Questa Engineering Corporation, Mid-Higuera Flood Control Project Hydrology & Hydraulic
Analysis. July 2009.
SWCA, Mid-Higuera Bypass Flood Control Project Visual Impact Assessment. May 2016.
Wallace Group, Mid-Higuera Bypass Site Plan, Grading Plan, Vegetation Enhancement Plan.
November 2014.
Wallace Group, Project Report Preliminary Design Draft for Review Mid-Higuera Bypass San
Luis Obispo. October 2014.
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Mid-Higuera Bypass Project FSEIR
7.1.2 EIR Preparers
The primary author of this EIR was Keith Miller, Environmental Resource Specialist with the
County of San Luis Obispo Department of Public Works (Public Works). EIR issue area
assessments were based primarily on background technical resources reports prepared by sub-
consultants including SWCA Environmental Consultants and Padre Associates, and other
Public Works staff, included Kate Ballantyne, Environmental Division Manager, as well as Eric
Weir and Katie Drexhage, Environmental Resource Specialists.
Page 126 of 669
PLANNING COMMISSION AGENDA REPORT
SUBJECT: GENP-0436-2022 STUDY SESSION ON GENERAL PLAN CLIMATE
ADAPTATION AND SAFETY ELEMENT UPDATE
PROJECT ADDRESS: Citywide BY: Teresa McClish, Housing Policy and
Programs Manager; Chris Read,
Sustainability Manager; Lucia Pohlman,
Sustainability and Natural Resource Analyst;
Kyle Bell, Housing Coordinator
Phone Number: (805) 783-7840
E-mail: tmcclish@slocity.org
FILE NUMBER: GENP-0436-2022 FROM: Tyler Corey, Deputy Director of
Community Development
RECOMMENDATION
Receive a presentation on the Workshop Draft of the General Plan Climate Adaptation
and Safety Element Update, including the Draft Hazards and Vulnerability’s Report,
review draft vision, goals, policies and programs, and provide comments or direction as
appropriate.
1.0 SUMMARY
The Safety Element of the General Plan was last updated in 2014, although it has not
been comprehensively updated since 2000. In accordance with state law (Senate Bill
379: Government Code Section 65302) that requires integration of comprehensive
climate adaptation and resilience strategies, the City applied and received a Sustainable
Communities Grant from the California Department of Transportation. The grant work
concluded in February of 2022 and provided an opportunity to investigate and develop a
comprehensive approach to building resilience to climate change in the community and
local transportation system. The project was called Resilient SLO and is summarized on
the City’s website (https://www.slocity.org/government/department-directory/city-
administration/office-of-sustainability-and-natural-resources/resilient-slo-2246).
The updated Climate Adaptation and Safety Element is intended to satisfy several state
requirements as required by legislation passed over the past several years including
Senate Bill (SB) 379 (Climate Change and Resilience), SB 99 (Emergency Evacuation
Routes), SB 1000 (Environmental Justice), Assembly Bill 747 (Emergency Evacuation
Routes), the Alquist-Priolo Earthquake Faulting Zone Act, and the National Flood
Insurance Program.
Under state law, a safety element promotes protection for the community from
unreasonable risks related to slope instability, seismic activity, subsidence, liquefaction,
known geologic hazards, flooding, wildland and urban fires, tsunami, seiche, dam failure,
and climate change.
Meeting Date: 10/26/2022
Item Number: 6a
Time Estimate: 90 Minutes
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
The draft Climate Adaptation and Safety Element (CASE) newly integrates climate
adaption and environmental justice and updates policies and programs throughout the
element.
2.0 COMMISSION’S PURVIEW
For the purposes of this study session the Planning Commission will review and provide
input on the draft CASE. This meeting holds two primary roles in the Safety Element
update process: 1) provide a forum for public discussion and consensus building; and 2)
provide policy and program direction to staff. The input received at the meeting will be
incorporated into the project materials prior to final review by the Planning Commission
and City Council.
3.0 PROJECT INFORMATION
Resilient SLO
The City applied and received a Sustainable Communities Grant from the California
Department of Transportation to investigate and develop a comprehensive approach to
building resilience to climate change in the community and local transportation system.
The Resilient SLO project included technical analysis of hazards associated with climate
change, adaptation strategies to increase local resilience to anticipated impacts, and
robust community engagement. The Resilient SLO project team was led by the City and
included City staff and a CivicSpark Fellow, the Local Government Commission (now
Civic Well), a consulting team including Ascent Environmental, CBEC Eco -Engineering,
and Fehr and Peers, and faculty at Cal Poly. The project findings and adaptation
strategies have been integrated into the Draft CASE update.
According to the World Meteorological Organization1, 2021 was one of the seven hottest
years on record, with all seven of those years occurring since 2015 . Over that same
period, San Luis Obispo has experienced historic wildfire smoke, drought, heat, and
flooding. While our community is doing its part to reduce greenhouse gas emissions and
prevent the worst-case climate disasters from happening, climate chan ge impacts are
here and will continue to increase for the foreseeable future2.
The City of San Luis Obispo is updating its Safety Element of the General Plan in
accordance with SB 379 to address hazards throughout the City and acknowledge the
extremely disruptive impacts of a changing climate. The City can establish an equitable
policy framework for managing the current and coming disruptions by adding an additional
lens of climate adaptation, community resilience, and environmental justice to the City’s
Safety Element of the General Plan.
1https://public.wmo.int/en/media/press-release/2021-one-of-seven-warmest-years-record-wmo-
consolidated-data-shows
2 On August 19, 2020, Council approved the City’s Climate Action Plan for Community Recovery, and
adopted Resolution 11159 (2020 Series), which includes the goal of carbon neutrality by 2035. While the
City continues to reduce local emissions, it is important to recognize that warming due to anthropogenic
activities from the pre-industrial period to the present will persist and continue to cause further long-term
changes in the climate system
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Relevant California Law
Government Code Section 65302(g) requires California cities and counties to include a
Safety Element as part of their General Plan. The intent of a safety element is to reduce
the potential short and long-term risk of death, injuries, property damage, and economic
and social dislocation resulting from known hazards including, fires, floods, droughts,
earthquakes, and landslides. Traditionally, a local government safety element would look
to historic disaster indicators of the types of disasters a community might face in the
future.
In response to the climate crisis, several state laws have added additional requirements
for inclusion in safety elements. Pertinent legislation is summarized in the project state
compliance timeline (CASE Appendix B) and is incorporated throughout the project as
applicable. The primary focus of Resilient SLO stems from SB 379 and SB1000 as
summarized below:
Senate Bill 379 requires jurisdictions to address climate adaptation and resiliency
strategies in their safety elements.3 State requirements to address climate adaptation
include preparation of: a vulnerability assessment informed by applicable federal, state,
regional, and local agencies; adaptation and resilience goals and policies; and
implementation measures.
SB 1000 requires jurisdictions with “disadvantaged communities” to address
environmental justice in their General Plan. Jurisdictions with disadvantaged communities
must address unique or compounding health risks in disadvantaged communities,
promote civil engagement in the public decision-making process, and prioritize programs
and improvements that address the needs of these communities. While the City does not
have any State designated “disadvantaged communities”, the regional Disadvantaged
Communities Assessment approved in June 2021 by the San Luis Obispo Council of
Governments (SLOCOG) provides a regional definition and identifies specific areas in the
City that are considered disproportionately burdened based on 13 variables related to
socioeconomic and population-based factors4.
Commitment to Equity
Diversity, Equity, and Inclusion is a Major City Goal in the 2021-2023 Financial Plan to
ensure policies and investments are managed in accordance with environmental, social
and governance practices. The City has worked to ensure equity has been included as a
central focus from the beginning of the Resilient SLO work effort to inform the CASE
consistent with SB 1000 provisions, including protecting local communities from
disproportionate environmental harm; promoting public health and safety; elevating
marginalized communities in the decision-making process; and following California
Governor’s Office of Planning and Research (OPR)’s best practice guidance (CASE
3 For more information about SB 379, see:
https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201520160SB379
4 See San Luis Obispo Council of Governments Disadvantaged Communities page: Disadvantaged
Communities | slocog
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Appendix F-1). The City conducted a community survey of social infrastructure using
participatory Asset Mapping (CASE Appendix D).
Resilient SLO Findings Used to Inform the Draft CASE
In compliance with SB 379 the State of California has developed the California Adaptation
Planning Guide5 (APG) as a resource for local governments engaged in adaptation and
resiliency planning to address impacts of climate change. Figure 1 illustrates how the
Resilient SLO Planning Process was modeled after the APG.
Figure 1: Resilient SLO Planning Process
The City has identified baseline conditions and assessed vulnerability to climate hazards,
and developed strategies for adaptation, completing the first three steps of the APG
planning process and has drafted the CASE for review and consideration as the final
phase of the process. A description of each step is summarized below:
Step 1: Project Initiation and Baseline Assessment
The City worked with its technical consultant, Ascent Environmental, to develop the
Baseline Conditions Report (CASE Appendix E). The report assesses the City’s current
climate-related hazards and provides a baseline for key characteristics of the community
that are likely to be affected by climate change.
The City’s community assets (i.e., infrastructure, functions, and populations) were
assessed for their historic and current exposure to climate-related hazards. The
assessment also documents social and economic conditions in recognition of the
interconnectedness of all sectors and aspects of society. A community priorities survey
was conducted and included in report findings (CASE Appendix B). The report includes
an existing hazards assessment, provides an overview of sensitive infrastructure,
populations, and functions, and summarizes key findings. Key finding topic areas include
flooding, extreme heat and drought, wildfire and associated impacts, sensitive
infrastructure, and vulnerable populations and community functions.
5 The State of California’s adaptation resources are available at: https://resilientca.org/
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Page 131 of 669
Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Step 2: Vulnerability Assessment and Hazards Report
The second step of the Resilient SLO project includes the comprehensive Climate
Change Hazards and Vulnerabilities Report (CASE Appendix A). The report identifies
and characterizes climate-related hazards and other climate effects th at are anticipated
to affect the City, its residents, and visitors. The report was developed using the best
available information regarding climate change projections for the City and the Central
Coast region, relevant information on current efforts to adapt to climate change, and best
practices and guidance provided by the State and other sources specific to climate
adaptation planning.
Building on the Baseline Conditions Report, impacts from climate-related hazards under
historic conditions are assessed using the Cal-Adapt model to evaluate what changes in
climate variables will occur over three time periods, and at what magnitude. The analysis
is organized into the following four distinct hazard categories: Temperature and Extreme
Heat, Long-Term Drought, Wildfire, and Precipitation and Flooding.
Though the City is exposed to other natural and human -made hazards such as seismic
events or hazardous waste that are also addressed in the City’s Safety Element and the
County Multi-Jurisdictional Hazard Miti gation Plan, the report assesses hazards that are
going be affected and exacerbated by climate change, focusing specifically on how
these hazards are likely to increase in frequency and severity.
The Resilience Roundtable, a community-led advisory body that helped the City guide
the approach and focus of the Resilient SLO project and the City’s Safety Element update ,
helped identify priorities through the community outreach process. These priorities were
then supplemented using hazard mitigation and emergency operation planning resources
developed previously by the City and the County, and further identified with priority
sensitive populations and assets. The set of sensitive populations, assets, and community
functions analyzed in this step are organized into the following three general categories.
The report analyzes social vulnerability and environmental justice concerns that could
place certain populations or areas at a disproportionately higher risk of climate change
related impacts are assessed and mapped using data from SLOCOGs disadvantaged
communities and the California Healthy Places Index that incorporates climate -resiliency
metrics to describe a community’s overall health. In this analysis, ranking for the combined
census tracts in the City places it in the 61st percentile, meaning it has healthier community
conditions than 61 percent of other California census tracts. The data within this analysis
helps identify vulnerabilities in specific populations and geographic areas for each hazard
discussion.
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Key findings for environmental justice and vulnerable populations include:
1. High cost of living relative to household income.
2. Some neighborhoods to the east and west of South Higuera include a high
percentage of elderly and disabled residents, a high percentage of residents
experiencing linguistic isolation, low access to supermarkets and grocery stores,
and a larger percentage of residents earning less than 200 percent of the federal
poverty level.
3. The city’s homeless populations are particularly vulnerable to climate related
hazards with less access to resources to protect themselves during emergencies,
often dwell in or near flood plains and areas with higher wildfire risk, and lower
levels of access to transportation.
Climate hazards assessment and vulnerability are scored based on magnitude of risk to
and potential impacts on natural systems, the built environment, and community
resilience. Importantly the assessment includes the City’s plans, resources and
considerable work to date in the development of adaptive capacity to mitigate climate -
related hazards when impacts do occur some of which are described in CASE Appendix
A (Table 23).
Findings concerning changes in risk and associated impacts are included in a summary
booklet (Attachment 2, Hazards and Vulnerabilities Summary Booklet) and documented
in the full Climate Change Hazards and Vulnerability Report. Ultimately, projected
weather extremes including long-term drought, extreme heat events, increased wildfire
risk, and extreme storm events are anticipated to increase in intensity and frequency as
the average global temperature increases to between 1.5 a nd 2°C. As a result, the City
must continue to prepare and adapt for the impacts of climate change, despite future
trends in local and global GHG emissions.
Step 3: Adaptation Strategy Development
Step 3 encompasses adaptation strategy and development. This allows the Development
of an adaption strategies menu based upon best practices and community input and an
integration guide to be used in workplans going forward to implement programs identified
in the CASE.
The set of adaptation strategies respond to the impacts from climate-related hazards
discussed in the Hazards and Vulnerabilities Report and works to build upon the
comprehensive set of plans and initiatives the City has already undertaken to reduce risk
from natural hazards that will be exacerba ted by climate change. The strategies include
the four main hazard categories included in the Hazards and Vulnerabilities Report. The
strategy ideas are also included in a summary booklet (Attachment 3, Adaptation Strategy
Options Booklet) and were used to inform the draft Climate Adaptation and Safety
Element. CASE.
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
Climate Adaptation and Safety Element
The draft CASE updates goals, policies and programs of the existing element in
accordance with state laws and the best available science, best practices an d community
input gained throughout the Resilient SLO project. New information concerning climate
adaptation equity and environmental justice are integrated throughout the element. A
new section dedicated to environmental justice is also included.
Vision and Goal Setting
The focus of the current General Plan Safety Element is to minimize injury and loss of life
from natural and manmade hazards. Through connecting new state requirements and
guidance for climate adaptation, regional plans and partnerships, Major City Goals, and
robust community collaboration on the topic of climate resiliency, a comprehensive vision
for safety and resiliency has been provided for consideration. The CASE Vision Statement
(see below) stems from shared experiences as a community and is intended to serve as
a guiding compass for the decisions made today and in the years to come for the City to
adapt to and thrive despite a changing climate. the vision is founded in the understanding
that the climate crisis has given the City the responsibility to prepare for the future and
the opportunity to create a brighter, equitable, and more resilient future for all who live,
work, and visit the city.
The City of San Luis Obispo works diligently to protect all forms of life
and property. While the changing climate has impacted us in expected
and unexpected ways, the priorities identified by the community and our
regional partners have shaped a San Luis Obispo that is thriving,
equitable, and resilient. Community members, businesses, and
neighborhoods support each other through climate disruptions, and civic
life is stronger than ever. Critical facilities are resilient, incorporate
innovative sustainability practices, and continue to provide core
community functions in a cost-effective manner. San Luis Obispo’s
efforts also support environmental justice, and all community members
have access to services and opportunities to influence the way we adapt
to climate change. The world around us is impacted, but our natural
resources and our built environments are designed to provide places of
refuge and buffer against these disruptive forces. Climate change is one
of the biggest challenges we have ever faced, but we have risen together
to be safe, healthy, and prosperous.
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
CASE Goals
Goals formulated to align with the Climate Adaptation and Safety Element vision are
described below:
Goal 1: Public Safety
Minimize injury and loss of life, damage to public and private property,
and social and economic disruptions resulting from injury, death, and
property damage.
Goal 2: Community Resilience
All community members are enabled and empowered to prepare for,
respond to and recover from disruptions while seizing opportunities to
thrive in changing conditions.
Goal 3: City Government Resilience
The City’s facilities, infrastructure, and operations are resilient,
innovative, and continue to cost-effectively provide core functions and
services for all community members in times of acute disaster and
ongoing disruptions.
Goal 4: Environmental Justice
A diverse, equitable, and healthy community where those who are
disproportionately affected by natural hazards and climate change have
the resources and capacity to participate in public processes and have
an active role in preparing and responding to future impacts.
Goal 5: Natural Systems
The natural environment sustains and supports ecological and
community health, safety, and natural beauty, provides equitable
access to nature, and can adapt and keep pace with a dynamic,
changing climate.
Goal 6: Built Environment
Community buildings, public spaces and transportation systems
withstand the natural hazards and escalating impacts of climate
change, provide places of refuge, foster social cohesiveness, minimize
injury and loss of life, and equitably protect personal and community
assets.
Summary of Policies and Programs
Policies are specific statements that will guide decision-making. Policies serve as the
directives to staff, design professionals, decision makers and others who will initiate or
review new development projects or city programs. Some policies stand alone as
directives, but others require that additional actions be taken.
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
The Climate Adaptation and Safety Element organizes policies into four hazard types:
flooding, extreme heat, fire and earthquakes and other geologic hazards. Additionally,
policies that may co-solve for multiple climate hazards simultaneously are included in a
High Impact Multi-Hazard Resilience section. Policies specific to environmental justice
are highlighted in a section called Equity and Environmental Justice. The final section
includes policies related to city operations and emergency services. Please note that the
City’s General Plan includes a Water and Wastewater Element, that includes climate
informed policies related to prolonged drought.
Programs are the core of the City’s climate adaptation strategy. The programs translate
goals and policies into actions and follow policies in each section described above.
Programs are also listed in the Implementation section (Section D) of the CASE and
paired with responsible departments for monitoring purposes. As with all General Plan
Elements, progress on implementation is summarized annually in the General Plan
Annual Report.
4.0 PUBLIC OUTREACH
The draft CASE reflects the community’s vision for resilience to hazards and future
disruptions. A foundational first step in Resilient SLO’s outreach and engagement
strategy was to create a Community Outreach Plan that identified key stakeholders and
population groups; established guiding principles, goals, and triggers; and outlined
strategies and tactics that ensured the project was informed by community needs,
priorities, and interests.
In conjunction with each step in the project, the project team conducted robust community
engagement activities to gather input on community needs and priorities, educate
community members on climate risks and individual/community resiliency strategies, and
involve community members. Community input has shaped development of the CASE to
date, and consisted of virtual community events, online surveys, “Stories of Resilience”
submissions, a Resilience Roundtable, and Working Groups. Due to Covid -19 conditions,
community engagement was conducted virtually. A summary of the P ublic Outreach
efforts is provided as Appendix D to the draft CASE.
A unique aspect of the project has been the formation of the Resilience Roundtable, a
community group of local experts that provides input to staff on the City’s approach to
identifying climate hazards, vulnerabilities and adaptation strategies. The 14 Roundtable
members were intended to represent a diversity of backgrounds and expertise areas. The
Roundtable met throughout the development of the CASE and provided critical input on
key project deliverables to date.
5.0 ENVIRONMENTAL REVIEW
This California Environmental Quality Act (CEQA) does not apply to the recommended
action of this report, because this study session is intended to provide information and
involves no action by the Planning Commission and therefore does not constitute a
“Project” under CEQA Guidelines Section 15378.
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Item 6a
Climate Adaptation and Safety Element (CASE) Update
GENP-0436-2022
Planning Commission Report – October 26, 2022
6.0 ATTACHMENTS
A - Draft Climate Adaptation and Safety Element
B - Hazards and Vulnerability Assessment Summary Booklet
C - Adaptation Strategy Options Booklet
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Climate Adaptation and Safety Element | i
City of San Luis Obispo
990 Palm Street
San Luis Obispo, CA 93401
Page 139 of 669
Table of Contents
Page 140 of 669
Table of Contents
City of San Luis Obispo Climate Adaptation and Safety Element 2022
City of San Luis Obispo
Climate Adaptation and Safety Element
Adopted
(Month Day, Year)
City Council
Erica A. Stewart, Mayor Andy Pease
Carlyn Christianson Michelle Shoresman
Jan Marx
Planning Commission
Emily Francis Steven Kahn
Michael Hopkins Robert Jorgensen
Juan Miguel Munoz-Morris Justine Cooley
David Houghton
Resilience Roundtable
Adrianne Greve, Robert Hill, Co-Chairs
Lauren Bell, James Blattler, Michael McCullough, Brian Messerly, Michael Parolini, Sara Sanders, William
Siembieda, Robert Spector, Hope Springer, Matt Ritter, Kayla Rutland, Eric Veium, Jenn Yost
City Management
Derek Johnson, City Manager
Shelly Stanwyck, Assistant City Manager, Community Services
Greg Hermann, Deputy City Manager
City Staff
Keith Aggson, Kyle Bell, James Blattler, Michael Codron, Tyler Corey, Hal Hannula, Robert Hill, Beya Makekau,
Matt Horn, Roger Maggio, Teresa McClish, Freddy Otte, Lucia Pohlman, Chris Read, Luke Schwartz, Shawna
Scott, Ryan Tomlinson, Naomi Albert (Civic Spark Fellow)
and many others
Consultant Support
Ascent Environmental, Civic Well (formally Local Government Commission) Cbec, Fehr & Peers
City of San Luis Obispo
919 Palm Street
San Luis Obispo, CA 93401-3218
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Climate Adaptation and Safety Element | i
A. INTRODUCTION ............................................................................................................................ 3
B. CLIMATE ADAPTATION AND SAFETY ELEMENT GOALS .................................................................. 6
C. POLICIES AND PROGRAMS ............................................................................................................. 8
1. High Impact Multi-Hazard Resilience 9
2. Equity and Environmental Justice 13
3. Flooding 18
4. 4. Extreme Heat 39
5. 5. Fire 49
6. 6. Earthquakes and other Geologic Hazards 63
7. 7. City Operations and Emergency Services 70
D. IMPLEMENTATION ...................................................................................................................... 82
E. REFERENCES ................................................................................................................................ 93
APPENDICES
A Resilient SLO Climate Change Hazards and Vulnerabilities Report
Appendix A-2 Flood figures
B Compliance with Laws and Regulations
C San Luis Obispo County Multi-jurisdiction Hazard Mitigation Plan Annex G
D Public Outreach summary
E Resilient SLO Baseline Conditions Report
F Environmental Justice Additional Information
G Cal Fire San Luis Obispo County Fire Hazard Severity Zone Ma p
H SLOMC Chapter 17.78 Floodplain Management Regulations
DRAFT FIGURES (All figures under review prior to final document)
Figure 1: Regionally Defined Disadvantaged Communities in the City of San Luis Obispo. ..... 15
Figure 2 Waterways and Floodplain Areas in the City of San L uis Obispo with
Critical Facilities ...................................................................................................................................... 20
Figure 3 Flood Depth: Full Extent - Q100 (Historic) ................................................................. 27
Figure 4 Flood Depth: SLO-Stenner - Q10 (Historic) ............................................................... 28
Figure 5 Flood Depth: SLO-Stenner - Q10 (Future 2070-2099 – RCP 8.5) ......................... 29
Figure 6 Flood Depth: SLO-Stenner - Q100 (Historic) ............................................................. 30
Figure 7 Flood Depth: SLO-Stenner - Q100 (Future 2070-2099 – RCP 8.5) ....................... 31
Figure 8 Flood Depth: SLO-Prefumo - Q10 (Historic) .............................................................. 32
Figure 9 Flood Depth: SLO-Prefumo - Q10 (Future 2070-2099 – RCP 8.5) ........................ 33
Figure 10 Flood Depth: SLO-Prefumo - Q100 (Historic) ............................................................ 34
Figure 11 Flood Depth: SLO-Prefumo - Q100 (Future 2070–2099 – RCP 8.5) ..................... 35
Figure 12 Average Annual Maximum and Minimum Temperatures in the City (1926-2018) ...... 39
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Table of Contents
Figure 13 Changes in Annual Average Temperature in San Luis Obispo County
through 2099 ........................................................................................................................................... 41
Figure 14 Urban Heat Island Effect and Tree Cover in the City ............................................... 45
Figure 15 Wildfire Hazard Severity Zones in and Surrounding the City of San Luis Obispo
with Critical Facilities ............................................................................................................................. 51
Figure 16 Wildfire Perimeters for Wildfires within 10 Miles of the City of San Luis Obispo
(1900–2020) ........................................................................................................................................... 52
Figure 17 PG&E Transmission Lines in the City of San Luis Obispo ...................................... 55
Figure 18 Projected change in average annual area burned within San Luis Obispo County
through 2099 ........................................................................................................................................... 57
Figure 19 Seismic Hazard Designation Area ............................................................................... 64
Figure 20. Regional Faults ............................................................................................................... 65
Figure 21 Liquefaction Risk Areas ................................................................................................ 67
Figure 22 Airport Land Use Safety Zones………………………………………………….75
TABLES
Table 1 Types of Equity in Adaptation Planning .............................................................. 13
Table 2 Climate-induced Changes in Peak Stream Flow for the San Luis Obispo
Creek Watershed ............................................................................................... 24
Table 3 Changes in Average Annual Temperature in City of San Luis Obispo ............... 40
Table 4 Changes in Extreme Heat Events in City of San Luis Obispo ............................ 42
Table 5 Changes in Annual Average Area Burned in San Luis Obispo County .............. 58
Table 6 Critical Facilities and Infrastructure in the City of San Luis Obispo .................... 72
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Climate Adaptation and Safety Element | 3
The City of San Luis Obispo (City) is committed to protecting the community from natural and
human-made hazards and building resilience to existing and projected climate change risks. The
Climate Adaptation and Safety Element assesses the city’s vulnerability to these hazards and
establishes goals, policies, and implementation measures to protect people, property, and the
natural environment. It is designed to realize an equitable, resilient community that thrives
despite the changing climate and other known hazards, as articulated below in the Climate
Adaptation and Safety Element’s Vision.
CLIMATE ADAPTATION AND SAFETY ELEMENT VISION
The City of San Luis Obispo works diligently to protect all forms of life and
property. While the changing climate has impacted us in expected and
unexpected ways, the priorities identified by the community and our regional
partners have shaped a San Luis Obispo that is thriving, equitable, and resilient.
Community members, businesses, and neighborhoods support each other
through climate disruptions, and civic life is stronger than ever. Critical facilities
are resilient, incorporate innovative sustainability practices, and continue to
provide core community functions in a cost-effective manner. San Luis Obispo’s
efforts also support environmental justice, and all community members have
access to services and opportunities to influence the way we adapt to climate
change. The world around us is impacted, but our natural resources and our
built environments are designed to provide places of refuge and buffer against
these disruptive forces. Climate change is one of the biggest challenges we
have ever faced, but we have risen together to be safe, healthy, and prosperous.
PURPOSE
The Climate Adaptation and Safety Element serves as the City’s Safety and Environmental
Justice elements, which are required elements of general plans subject to the requirements of
Government Code 65302(g)(h). Under state law, a safety element promotes protection for the
community from unreasonable risks related to slope instability, seismic activity, subsidence,
liquefaction, known geologic hazards, flooding, wildland and urban fires, tsunami, seiche, dam
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Introduction
Climate Adaptation and Safety Element | 4
failure, and climate change. An environmental justice element addresses unique or compounded
health risks in vulnerable and disadvantaged communities by decreasing pollution exposure,
increasing community assets, and improving overall health.
The City is focusing on climate change adaptation in this Safety Element update because state
law requires that safety elements include a vulnerability assessment that identifies the risks
posed by climate change and a series of adaptation goals, policies, and implementation
measures designed to protect the community (Senate Bill [SB] 379, 2015). The City’s Hazard
and Vulnerability Assessment is included in Appendix A. The City is also including climate
adaptation due to the unprecedented disruptions that climate change will cause through and
beyond General Plan buildout. Due to decades of rapidly increasing global greenhouse gas
(GHG) emissions and insufficient climate action at all levels of government and industry,
atmospheric GHG concentrations have reached a level that guarante es substantial and
unavoidable impacts for the foreseeable future. California’s recent historic heat, wildfires,
droughts, floods, mudslides, and public safety power shutoffs represent the types of climate
change impacts that will be experienced with increasing frequency and severity. These impacts
threaten to make all the significant issues currently faced by the City (e.g., economic recovery,
the housing crisis, homelessness, equity, sustainable water supply, etc.) more critical,
challenging, and expensive. By centering climate change consideration in General Plan goals,
policies, and programs now, the community can have sufficient capacity to thrive in the face of
a rapidly changing future.
The City is focusing on the integration of environmental justice in this Safety Element update
because as the state requires analysis of existing hazards and climate change impacts on the
community related to existing and future hazards, climate change can further impact vulnerable
and disadvantaged communities that already suffer from disproportionate environmental
burdens and health risks. These communities would experience heightened risk and increased
sensitivity to climate change due to having less capacity and fewer resources to cope with, adapt
to, or recover from climate impacts (Office of Planning and Research, July 2020). Consideration
of environmental justice in climate adaptation and safety planning provides an opportunity to
improve resilience of the entire community over time, especially vulnerable and disadvantaged
populations.
REGULATORY AND PLAN CONSISTENCY
The Climate Adaptation and Safety Element has been developed in compliance with State laws
and regulations, consistent with other plans prepared or adopted by the City, including the San
Luis Obispo County Multi-Jurisdiction Hazard Mitigation Plan (Hazard Mitigation Plan), Climate
Action Plan for Community Recovery, and other elements of the City’s adopted General Plan. A
brief description of laws, regulations, and plans reviewed for consistency is provided below, with
additional information provided in Appendix B (Compliance with Laws and Regulations).
Consistency with state laws and regulations
Key State laws informing preparation of the Climate Adaptation and Safety Element, including
recent legislation related to planning for climate change adaptation and environmental justice,
Include Senate Bill (SB) 379 (Climate Change and Resilience), SB 99 (Emergency Evacuation
Routes), SB 1000 (Environmental Justice), Assembly Bill 747 (Emergency Evacuation Routes),
the Alquist-Priolo Earthquake Faulting Zone Act, and the National Flood Insurance Program .
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Introduction
Climate Adaptation and Safety Element | 5
Consistency with City General Plan
To ensure that the goals, policies, and programs included in the Climate Adaptation and Safety
Element are internally consistent with other elements of the City’s General Plan a policy audit
was conducted to identify any similar or overlapping goals, policies, and programs from other
elements of the City’s adopted General Plan, and other plans the City has adopted that support
implementation of the General Plan . Based on this assessment, the City finds that the Climate
Adaptation and Safety Element is consistent with the other elements of the General Plan.
Consistency with multi-jurisdictional Hazard Mitigation Plan
In June 2020, the City adopted the San Luis Obispo County Multi-Jurisdictional Hazard
Mitigation Plan (Hazard Mitigation Plan) and accompanying city-specific Annex G: City of San
Luis Obispo (Appendix C). The city-specific annex includes an assessment of natural and
manmade hazards affecting the city and a comprehensive set of goals, objectives, strategies,
and actions to mitigate potential impacts to life and property. It addresses the following medium
and high significance hazards based on the potential impact which takes into account the
geographic area, probability of future occurrences and magnitude/severity :
• Adverse Weather: Thunderstorm/Heavy Rain/Hail/Lighting/Dense Fog/Freeze
• Adverse Weather: High Wind/Tornado
• Agricultural Pest Infestation and Disease
• Biological Agents
• Drought and Water Storage
• Earthquake
• Flood
• Human Caused: Hazardous Materials
• Wildfire
The Hazard Mitigation Plan was submitted to the Governor’s Office of Emergency Services and
Federal Emergency Management Agency (FEMA) for approval. By reviewing and updating the
Hazard Mitigation Plan every 5 years, the City maintains eligibility for certain hazard mitigation
funding from FEMA. The Hazard Mitigation Plan is incorporated by reference into the Climate
Adaptation and Safety Element. The goals and policies of the Climate Adaptation and Safety
Element are complementary to and consistent with the recommended mitigation strategy of the
Hazard Mitigation Plan, which the City also will consult when addressing known hazards.
Consistency with the Climate Action Plan for Community Recovery
In August 2020, the City adopted the Climate Action Plan for Community Recovery. It establishes
a community-wide goal of carbon neutrality by 2035 and a municipal operations goal of carbon
neutrality by 2030, adopts sector specific emissions goals, and provides foundational actions to
establish a trajectory towards achieving those goals. The plan recognizes the importance of
reducing greenhouse gas (GHG) emissions to limit the amount of global warming that will occur
and lessen the severity of future climate impacts, while also acknowledging that climatic changes
have already been set into motion as a result of past, present, and future GHG emissions
generated throughout the world. The Climate Adaptation and Safety Element illustrates the City’s
commitment to simultaneously addressing the causes and impacts of climate change.
The San Luis County Multi-
jurisdiction Hazard Mitigation Plan
is incorporated by reference into
the Climate Adaptation and Safety
Element
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Climate Adaptation and Safety Element | 6
ELEMENT STRUCTURE
The Climate Adaptation and Safety Element includes a set of broad goals for various aspects of
the city derived from broad public outreach summarized in Appendix D. To provide a holistic
approach, the goals focus on desired future conditions for key physical, natural, and social
systems needed to achieve community safety and resilience. To facilitate ease of reference, this
Element is organized into sections based on major hazards present in the city. These sections
include a discussion of the hazard, how climate change is projected to influence t he hazard
(where relevant), and a comprehensive set of policies and programs to help achieve the goals.
A brief definition of goal, policy, and program is provided below.
Goal - A statement that describes in general terms a desired future condition or “end” state.
A goal serves to set a general direction.
Policy – A statement that guides a specific course of action for decision -makers to use to
achieve a desired goal.
Program – An action, procedure, program, or technique that carries out a policy.
The Climate Adaptation and Safety Element is also supplemented by a series of appendices
which provide additional information that was used to develop this Element.
CLIMATE ADAPTATION AND SAFETY ELEMENT GOALS
The Climate Adaptation and Safety Element has six goals, each of which contributes to achieving
the vision presented in Chapter One. The six goals are as follows:
Goal 1: PUBLIC SAFETY
Minimize injury and loss of life, damage to public and private property, and social
and economic disruptions resulting from injury, death, and property damage.
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Climate Adaptation and Safety Element Goals
Climate Adaptation and Safety Element | 7
GOAL 2: COMMUNITY RESILIENCE
All community members are enabled and empowered to prepare for, respond to
and recover from disruptions while seizing opportunities to thrive in changing
conditions.
GOAL 3: CITY GOVERNMENT RESILIENCE
The City’s facilities, infrastructure, and operations are resilient, innovative, and
continue to cost-effectively provide core functions and services for all community
members in times of acute disaster and ongoing disruptions.
GOAL 4: ENVIRONMENTAL JUSTICE
A diverse, equitable, and healthy community where those who are
disproportionately affected by natural hazards and climate change have the
resources and capacity to participate in public processes and have an active role
in preparing and responding to future impacts.
GOAL 5: NATURAL SYSTEMS
The natural environment sustains and supports ecological and community
health, safety, and natural beauty, provides equitable access to nature, and can
adapt and keep pace with a dynamic, changing climate.
GOAL 6: BUILT ENVIRONMENT
Community buildings, public spaces and transportation systems withstand the
natural hazards and escalating impacts of climate change, provide places of
refuge, foster social cohesiveness, minimize injury and loss of life, and equitably
protect personal and community assets.
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High Impact Multi-Hazard Resilience
Climate Adaptation and Safety Element | 8
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High Impact Multi-Hazard Resilience
Climate Adaptation and Safety Element | 9
1. High Impact Multi-Hazard Resilience
OVERVIEW
In the coming decades San Luis Obispo will experience more fires, floods, droughts, and
extreme heat than ever before. Throughout the development of this plan, the community has
called for bold, just, and proactive measures that build resilience amid increasing climate
hazards (Baseline Conditions Report, Appendix E). While some of the resilience solutions
presented in the Climate Adaptation and Safety Element will help our community adapt to a
specific hazard, this chapter identifies strategic actions wherein a singular change in City policy
or practice can co-solve for multiple climate hazards simultaneously. This chapter’s cross-cutting
policies and programs represent the highest leverage actions available to the City, which can
broadly improve the community’s ability to endure and recover from a range of disturbances.
Public infrastructure, private development, and natural resources are all subject to a confluence
of natural and manmade hazards that can threaten human life and safety. The high-impact multi-
hazard resilience solutions presented in this chapter offer clear points of intervention that boost
community resilience amidst the unpredictable and compounding threat of fires, floods,
earthquakes, and droughts facing San Luis Obispo.
This chapter also includes actions that boost social cohesion, connectedness, and community
solidarity – as social cohesion is one of the strongest indicators of resilience during disaster
events and post-disaster recovery efforts (Townshend et al. 2015). Alongside the steps the City
and partner agencies are taking, it is important to recognize the role community organizations
and informal social networks can play in building adaptive capacity to the impacts of climate
change, especially for vulnerable populations.
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High Impact Multi-Hazard Resilience
Climate Adaptation and Safety Element | 10
MULTI-HAZARD RESILIENCE POLICIES
Policy MH-1.1: CLIMATE ADAPTATION AND SAFETY ELEMENT POLICIES
The policies and programs included in the Climate Adaptation and Safety Element are critical to
maintaining community safety and to supporting disaster preparedness.
Policy MH-1.2: CLIMATE-INFORMED CAPITAL IMPROVEMENT PROGRAM, ENGINEERING
STANDARDS AND NATURAL RESOURCES MANAGEMENT
The City shall incorporate climate projection data, risk modeling, and adaptive management, as
appropriate, to account for future changes in key climate variables (e.g., changes in precipitation
and flooding behavior, fire and smoke risk, maximum daily temperatures) in the City’s Capital
Improvement Program, Engineering Specifications and Standards, and natural resource projects
and planning documents.
Policy MH-1.3: POST-DISASTER RECOVERY RESOURCES
The City shall expand equitable access to post-disaster recovery resources for residents and
businesses (e.g., recovery funding, recovery services) including debris management.
Policy MH-1.4: REGIONAL COLLABORATION FOR CLIMATE ADAPTATION
The City shall integrate regional collaboration as a key component of the City’s climate
adaptation planning strategy, recognizing the regional nature of climate impacts and climate
adaptation strategies.
MULTI-HAZARD RESILIENCE PROGRAMS
Program MH-1.5: UPDATE THE CITY’S CAPITAL IMPROVEMENT PROGRAM TO
INCORPORATE CLIMATE PROJECTIONS
Assess existing infrastructure systems vulnerable to changes in key climate variables (e.g.,
flooding, extreme heat) and incorporate upgrades to critical infrastructure in the City’s Capital
Improvement Projects (CIP) planning process. Identify key pieces of existing infrastructure that
are likely to be compromised by climate impacts and prioritize these upgrades as part of the City
CIP process. Use data from the Climate Change Hazards and Vulnerabilities Report, th e Cal-
Adapt tool, and supplemental climate projection data and research to inform an appropriate list
of infrastructure upgrades.
Program MH-1.6: UPDATE CITY’S ENGINEERING STANDARDS AND SPECIFICATIONS TO
INCORPORATE CLIMATE PROJECTIONS
The City shall evaluate and update the City’s building and engineering standards and
specification to account for future changes in key climate variables (e.g., changes in the size of
large storm events, maximum daily temperatures) that are likely to affect critical infrastructure.
Use data from the Climate Change Hazards and Vulnerabilities Report, the Cal-Adapt tool, and
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High Impact Multi-Hazard Resilience
Climate Adaptation and Safety Element | 11
supplemental climate projection data and research to inform the updates to the City’s standards
update process. Use a climate-informed adaptive management approach to continually monitor
the performance of the updated building and engineering standards against the observed
changes in climate variables, adjusting standards as need to match future changes in these
variables caused by climate change.
Program MH-1.7: CLIMATE SMART NATURAL RESOURCE MANAGEMENT
The City shall integrate climate projections and adaptation projects (e.g., clearing or removal of
dead material and replanting with more resilient shrubs and trees) regarding changes in average
temperatures, extreme heat, flooding, fire, drought, etc. into updates of the City’s natural
resource planning documents as they occur, including, but not limited to:
• Open Space Conservation Plans
• Conservation Guidelines for Open Space Lands of the City of San Luis Obispo
• Waterway Management Plan.
Program MH-1.8: CLIMATE RESILIENCE HUBS
Work with community organizations, faith-based organizations, and other institutions to develop
a network of conveniently located Climate Resilience Hubs including a mix of public facilities,
community centers, businesses, and community-oriented facilities (e.g., churches, synagogues,
mosques). Ensure the chosen facilities are equipped to provide aid to vulnerable populations
during other emergency events such as periods of poor air quality from wildfire smoke, utility
disruptions, flooding events, or other climate-related hazards (CDC n.d.). Ensure the Climate
Resilience Center is centrally located and accessible.
Program MH-1.9: POST-DISASTER RECOVERY DEBRIS MANAGEMENT
Prepare and update solid waste agreement(s) addressing post disaster debris management
activities including clearing, collection, removal, and disposal.
Program MH-1.10: POST-DISASTER RECOVERY RESOURCES AND EDUCATION
Work with community organizations, the San Luis Obispo County Office of Emergency Services,
and other key stakeholders to: 1)assess effectiveness in post-disaster recovery efforts including
establishing metrics to ensure that post -disaster recovery resources are allocated equitably; 2)
Assess potential barriers for rehabilitation and rebuilding in post-disaster situations and develop
protocols to remove barriers; and 3) educate individuals and households about strategies to
increase preparedness for emergency events and climate -related impacts. Use information from
the City’s Hazards and Vulnerabilities Report (Appendix A) to identify areas in the City with
vulnerable populations (e.g., linguistically isolated households, elderly, youth, homeless,
individuals with chronic health conditions) to conduct targeted outreach to these neighborhoods
and areas in the City. Strategies could include:
• Creating emergency kits emergency supply kits for homes, cars, and at work locations
• Creating personal emergency funds for short- and long-term emergency events
• Implementing household hazard mitigation projects such as defensible space, home
hardening, earthquake retrofitting, and home insulating to improve ability to inhabit home
during and post emergency event or climate-related impact.
• Information on mental health and support services for post -disaster recovery
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Program MH-1.11: REGIONAL COLLABORATION AND COMMUNITY RESILIENCE
AMBASSADORS
Develop consistent communications and participate with key community partners including: 1)
communicate and provide updates on adaptation strategy implementation to the genera l public
and key partners including San Luis Obispo County, other incorporated cities in the County, and
community organizations; 2) continue the City’s active participation in the Central Coast Climate
Collaborative (4C) by sharing lessons learned, strategy collaboration opportunities, and
regionally relevant data included in the Climate Change Hazards and Vulnerabilities Report
(Appendix A); 3) identify members of the City’s Green Team to serve as city liaisons for regional
adaptation-focused organizations and key regional climate adaptation planning efforts ; 4) work
with community organizations and other institutions to establish a net work of Community
Resilience Ambassadors who can support outreach efforts, educate residents on climate
preparedness, and connect residents to existing resources and organizations.
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2. Equity and Environmental Justice
OVERVIEW
The City is committed to integrating diversity, equity, and inclusion in its operations and delivery
of community services. The intersection of equity, environmental justice, and public safety is
particularly important as the impacts of climate change will inequitably affect vulnerable and
disadvantaged communities.
The policies and programs in the Climate Adaptation and Safety Element integrate equity
considerations listed in Table 1, which derive from the State’s Adaptation Planning Guide (Cal
OES 2020) and align with the equity commitments made in the Climate Action Plan for
Community Recovery (City of San Luis Obispo 2021). In addition to having equity as a lens
through the entire Element, this Chapter provides policies and programs focused specifically on
equity and environmental justice.
Table 1 Types of Equity in Climate Adaptation and Public Safety Planning
Type Of Equity Equity Metrics
Procedural
Equity
Create processes that are transparent, fair, and inclusive in developing and
implementing any program, plan, or policy.
Ensure that all people are treated openly and fairly.
Increase the civic engagement opportunities of communities that are
disproportionately impacted by climate change.
Distributional
Equity
Fairly distribute resources, benefits, and burdens.
Prioritize resources for communities that experience the greatest inequities and
most disproportionate impacts and have the greatest unmet needs.
Structural
Equity
Make a commitment to correct past harms and prevent future unintended
consequences.
Address the underlying structural and institutional systems that are the root
causes of social and racial inequities.
Include adaptation strategies to eliminate poverty, create workforce
development, address racism, increase civic participation, protect housing
availability, increase education, and provide healthcare.
Source: Cal OES 2019.
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DISADVANTAGED COMMUNITIES IN SAN LUIS OBISP O
The San Luis Obispo Council of Governments (SLOCOG)
has defined disadvantaged communities as
disproportionately burdened areas in the region that are
economically distressed and/or historically
underrepresented as a part of the local government
process. The Disadvantaged Communities Assessment
identifies 13 variables that address a wide range of
socioeconomic and population-based factors to
geographically define these disproportionately burdened
areas. Figure 1 below includes the locations of the
Regionally Defined Disadvantaged Communities
identified in the city. For a more detailed discussion of
environmental justice including survey summary and
disadvantaged communities in the city, see Appendix F-
1 and F-2 and the Hazards and Vulnerabilities Report
(Appendix A).
Example: Utility Relief program
increases household resiliency
The City offers water and sewer bill relieve
programs for qualifying customers, which
are required by California Proposition 218
to be funded outside of revenues
generated by rate payers (i.e., water and
sewer customers). The City’s Customer
Assistance Program provides a 15 percent
discount on monthly water and sewer bills
for qualifying customers. The City also
shares information with the community
regarding other local, state, and federal
programs that may not be affiliated with the
City, but that can offer financial assistance
with utility bills.
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Source 1: Data received from SLOCOG in 2021 and from CBEC Engineering in 2020 and downloaded from City of San Luis
Obispo in 2020 and County of San Luis Obispo in 2020.
Draft Figure 1: Regionally Defined Disadvantaged Communities in the City of San Luis Obispo.
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EQUITY AND ENVIRONMENTAL JUSTICE POLICIES
Beyond the items listed below, environmental justice related policies and programs are
integrated throughout the safety element.
Policy EJ-2.1: EQUITY AND JUSTICE IN ALL POLICIES AND PROGRAMS
The City shall ensure that the implementation of the Climate Adaptation and Safety Element
prioritizes equity and justice and addresses the community’s greatest needs, including the needs
of persons living in poverty, older adults, children, persons with disabilities, people of color, and
immigrants.
Policy EJ-2.2: EQUITABLE CIVIC ENGAGEMENT
The City shall support an equitable and comprehensive approach to civic engagement and public
outreach on all aspects of City governance and delivery of services.
EQUITY AND ENVIRONMENTAL JUSTICE PROGRAMS
Program EJ-2.3: EMPOWER COMMUNITY ORGANIZATIONS
Identify key community organizations working with underserved and historically disadvantaged
communities and ensure these organizations and representatives from historically
disadvantaged communities play a substantive role in implementing the Climate Adaptation and
Safety Element.
Program EJ-2.4: ENSURE PUBLIC ENGAGEMENT NOTICING MANUAL ADVANCES
PROCEDURAL EQUITY
Maintain the Public Engagement Noticing Manual (PEN Manual) as the guiding framework for
all departments to participate in meaningful two-way communication with the public on all
aspects of County governance and delivery of services. Community outreach and education
opportunities should include multi-lingual options for both written materials and in -person
engagement. The events should also include demographic surveys as part of community
outreach events to ensure that participants are representative of the demographic makeup (e.g.,
race, age, ethnicity) of the city’s population as a whole. The City shall provide opportunities for
community organizations and other stakeholders to review strategy details before
implementation.
Program EJ-2.5: DEVELOP EQUITY CHECKLIST FOR CITY PROGRAMS AND CAPITAL
IMPROVEMENT PROJECTS
Use equity metrics included in the State’s Adaptation Planning Guide, or similar metrics, to
develop an Equity and Environmental Justice Project Checklist to be used during the design and
development of City-led programs and capital improvement projects to ensure they are
implemented equitably and, where appropriate, historically disadvantaged communities are
prioritized in receiving the benefits of the project.
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Program EJ-2.6: ESTABLISH COMMUNITY RESILIENCE FUND
Develop funding mechanisms through the State’s Integrated Climate and Resiliency Program
and develop criteria to administer a Community Resilience Fund that provides grants to
individuals or community organizations to implement projects that support social cohesion as it
relates to public safety, climate change impacts, and disaster recovery. Criteria would be
developed to evaluate applications and prioritize the allocation of funding to projects that focus
on protecting the most vulnerable population s (i.e., low-income, minority, or elderly populations).
PROGRAM EJ-2.7: REPORT ON EQUITY AND ENVIRONMENTAL JUSTICE PROGRESS
Include “Equity and Environmental Justice” as a category for reporting in the General Plan
Annual Report.
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3. Flooding
OVERVIEW
This chapter provides an overview of flood risk in the city
and includes a comprehensive set of policies and programs
to mitigate flooding impacts and recover from flooding
events when they occur.
FLOODING CHARACTERISTICS
Floods occur when the amount of water within a creek or
river channel exceeds the channel capacity, causing water
to spill over the banks and into the surrounding land. In
these flat, flood-prone areas beyond the channel, called floodplains, slow moving or stagnant
water that escapes the channel may remain until water levels within the channels recede or the
areas are drained by infrastructure, percolation, or evapotranspiration.
Naturally, these floodplain areas would have been flooded every few years, bu t as the city
developed onto portions of the floodplains of the creeks within the San Luis Obispo Creek
watershed, channel incision and flood protection measures constrained flows to the creeks.
During periods of intense rainfall, however, the watershed ou tflow, including urban runoff, can
exceed the capacity of the channels. Under existing conditions, different creeks within the
watershed may experience flooding every 10–25 years (Questa Engineering Corporation 2003).
There are several overall mechanisms by which flooding can occur:
• dam inundation flooding, in which impounded water is released because of dam
breaching;
• localized flooding, which occurs when intense rainfall overwhelms the capacity of local
drainage infrastructure; causing the ponding of wa ter; and
• riverine flooding, which occurs when channels (i.e., the relatively deep, narrow sections
of creeks and rivers) cannot contain the flow volume moving through them, causing water
to spill out into the overbank areas (i.e., the relatively wide, fla t regions on one or both
sides of the channel, also called “floodplains”).
According to the Annex G of the County’s HMP, the city is not at risk of dam inundation flooding,
as there are no major reservoirs within the watershed, and localized flooding is considered a
The City has adopted floodplain
management regulations in
Chapter 17.78 in the San Luis
Obispo Municipal Code that are
approved by FEMA that are
included by reference into the
Climate Adaptation and Safety
Element (Appendix H).
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minimal risk. The highest flooding concern for
the city is riverine flooding, which may include
“flash” flood risks (San Luis Obispo County
2019b).
SAN LUIS OBISPO CREEK
WATERSHED
As shown in Figure 3, San Luis Obispo Creek
flows through the city in a northeast to
southwest direction, passing through the
downtown area and generally following U.S.
Highway 101 (U.S. 101) on its way to the
Pacific Ocean at Avila Beach.
The watershed for San Luis Obispo Creek,
the land area that captures rainfall and
contributes water directly to the creek system,
covers an area of approximately 84 square
miles, ranging in elevation from
approximately 2,460 feet in the upp er
watershed near the Cuesta Grade to its outlet
into the Pacific Ocean. Along its main flow
path, it transitions from steep canyons to the
gently sloping alluvial plain underlying the
city, descending more than 2,230 feet to
downtown.
In the city’s downtown, San Luis Obispo
Creek flows through the “under-city culvert,”
consisting of a system of covered,
constructed channels between Osos Street
and Chorro Street before emerging into
Mission Plaza.
Further downstream, near the intersection of
Marsh Street and Higuera Street, San Luis Obispo Creek is joined by a major tributary, Stenner
Creek, which in turn receives flow from Brizzolara and Old Garden Creeks. San Luis Obispo
Creek then continues south along the alluvial plain, intercepting Prefumo Creek as i t exits
Laguna Lake and joining East Fork San Luis Obispo Creek near the Higuera Street/U.S. 101
interchange by the Johnson Ranch Open Space. Near the confluence of San Luis Obispo Creek
with Davenport Creek, the channel enters “the Narrows” (Questa Engine ering Corporation
2003), passing through a steep, confined canyon before being joined by San Miguelito Creek
coming out of See Canyon and discharging to the Pacific Ocean. Flows in the watershed are
“flashy,” meaning that water moves quickly through the system and that stream levels rise and
recede rapidly in response to rainfall events. This is a result of the steep topograph y of the upper
watershed and the relatively shallow soils, land cover, and rainfall characteristics for the region
(Questa Engineering Corporation 2003).
Flooding Definitions
Two interchangeable, technical terms
that characterize flood frequency are
used throughout the section and are
defined as follows:
Recurrence Intervals: Refers to how
often, on average, a given flood may
occur. A 100-year event, for example, is
described as an event that may occur
about once in every 100 years, on
average. However, this terminology can
be misleading because flood events are
statistical occurrences, and events may
occur more frequently than their
recurrence interval suggests.
Exceedance Probability: The
exceedance probability of a given flood
event is the percent chance that a larger
flood will occur in any given year, and it
is calculated by dividing the number 1 by
the recurrence interval. Thus, the “100-
year event” becomes the “1-percent
exceedance event,” or a flow rate that
has a 1-percent chance in any given year
of being equaled or surpassed by a larger
flow rate. This representation, although
interchangeable with the recurrence
interval, provides a more helpful way to
think about flood risk.
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and
processed by cbec eco engineering in 2020.
Draft Figure 2 Waterways and Floodplain Areas in the City of San Luis Obispo with
Critical Facilities
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HISTORICAL FLOODING
The San Luis Obispo Creek watershed has a long history of flooding, with a series of storms
over the last 50 years that have caused millions of dollars’ worth of damage.1 Damaging flood
events have occurred in 1868–1872, 1884, 1897, 1911, 1948, 1952, 1962, 1969, 1973, 1995,
1998, and 2001 (Questa Engineering Corporation 2003; City of San Luis Obispo 2014).
The flooding events in
January and March 1995
occurred during one of the
wettest periods on record,
causing the watershed to
be relatively saturated for
long periods, which
prevented soils from
absorbing incoming
precipitation. The 1995
flooding events followed
the 1994 Highway 41 fire,
which burned major areas
of the Stenner Creek and
upper San Luis Obispo
Creek watersheds and
caused increased runoff
and sediment delivery to
channels. Flow spilled out
of the San Luis Obispo
Creek channel in the region around Marsh and Higuera Streets, causing extensive damage, and
remained out of the creek banks for nearly 3 miles downstream. The events, for which the peak
flow was estimated to be the 17 -year flood event2 (6-percent exceedance probability), caused
$2.3 million in damage (Questa Engineering Corporation 2003).
Prior events were even more damaging: The 1969 flood cau sed $6.92 million in damage, and
the 1973 flood caused $13.6 million in damage. During the 1973 flood, depths of inundation over
U.S. 101 exceeded 4 feet near the Madonna Inn and were up to 3 feet near the Prefumo Creek
confluence (Questa Engineering Corporation 2003).
FLOOD RISK
Following the 1973 flood, watershed studies and plans were developed and updated, including
the 1974 U.S. Army Corps of Engineers floodplain study of San Luis Obispo Creek (USACE
1974), 1977 Nolte & Associates study (George S. Nolte & Associates 1977), and 1978 FEMA
flood insurance study. The extent of 100-yr and 500-yr flood zones, based on these studies, is
shown in Figure 3.
In 2003, the City’s Waterway Management Plan (WMP) was completed, which relied on updated
analyses for flow frequency. In general, the flow estimates provided by the WMP for a given
recurrence interval are higher than those reported in the prior studies, leading to the
1 Storm damages were normalized to reflect costs in the year 2000.
2 According to the flood frequency analysis conducted for the 2003 Waterway Management Plan (Questa Engineering Corporation 2003), which
represent updated flood frequency information compared to the Federal Emergency Management Agency study (1978).
Higuera Street, San Luis Obispo, January 1969 flood event.
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recommendation that the WMP be used for design considerations for projects in the city, as a
conservative assumption, as well as the adoption of the updated flow frequency estimates by the
City. According to the WMP, nearly all streams in the San Luis Obispo Creek watershed have
less than a 25-year (4-percent exceedance probability) flood capacity, with some experiencing
flooding in the 10- to 15-year range (Questa Engineering Corporation 2003).
FLOOD RISK FACTORS
For the San Luis Obispo Creek watershed, factors that may directly contribute to flooding are
infrastructure-induced flow constrictions, wildfire, and degraded riparian corridors (Questa
Engineering Corporation 2003). In terms of flooding from infrastructure, bridges often serve as
flow constrictions because the abutments, or structures connecting the bridge deck to the
ground, may occupy part of the floodplain for a channel in order to reduce the span width of the
deck. In addition, bridge piers can intercept transpo rted debris, particularly woody vegetation,
and reduce conveyance through the structure.
Undercity Culvert
One of the greatest flow constrictions in the watershed is the undercity culvert. This flow rate is
below the 25-year flood event (4-percent exceedance probability) according to FEMA flood
insurance studies (FEMA 1978), indicating that the culvert is unable to manage water flow during
the 25-year flood event. Flows exceeding the undercity culvert capacity may exit the channel at
Osos Street or further upstream at the Santa Rosa or Marsh Street bridges and cause overland
flooding within downtown, particularly along the Ma rsh Street corridor and areas surrounding the
creek channel.
Post-Wildfire Runoff
Post-wildfire runoff represents another risk for flooding because burned areas in the watershed
will contribute more runoff and higher sediment loads than vegetated areas. As previously
mentioned, the 1995 floods, which caused approximately $2.3 million in damages, followed the
1994 Highway 41 fire and the loss of vegetation on hillslopes contributed to high runoff volumes.
Overall, about one third of the San Luis Obispo Creek watershed is considered by the California
Department of Forestry and Fire Protection (CAL FIRE) to be in Very High Fire Hazard Severity
Zones, based on an analysis of publicly available GIS data (CAL FIRE 2020).
Degradation of the City’s Riparian Corridors
The degradation of riparian corridors, the thin strips of trees and other vegetation lining the
creeks, may contribute to flooding within the San Luis Obispo Creek watershed. Historically,
riparian zones would have been composed of tall, single -trunk sycamores, cottonwoods, and
willows, but these areas are now characterized by shrubby willow growth (Questa Engineering
Corporation 2003). This results in more low-hanging branches coming into contact with flowing
water, which increases the roughness of the creek channels and consequently reduces flow
velocities. When the water is slowed, water levels in the channel are increased and ove rflow into
surrounding lands becomes more likely.
The conversion of land to impervious surfaces as a result of urban development, known generally
as “urbanization” has indirectly affected flood risk by altering the shape and function of the creek
channels within the watershed. Overall, the San Luis Obispo Creek watershed is about 10 percent
urbanized, meaning that 10 percent of the land area within the basin3 that drains to the outlet of
3 Basin, or drainage basin, is another term for watershed.
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San Luis Obispo Creek at Avila Beach is covered by urban development. However, when
considering only the portion of the watershed upstream of Los Osos Valley Road, the drainage
basin is 15 percent urbanized (Questa Engineering Corporation 2003). Conversion to impervious
surfaces accompanying urban development results in higher runoff rates because rainfall cannot
be absorbed by the underlying soil from these surfaces. This causes water to enter the creek
channels more quickly and leads to higher flow volumes and faster channel velocities on a more
frequent basis. The City has adopted post construction stormwater regulations that include
provisions for the upgrade of existing developed sites upon redevelopment to improve historic
watershed processes through retention.
For periods of sustained, heavy rainfall, the watershed soils may be highly saturated at the time
of peak rainfall and the watershed may therefore, have a limited ability to absorb the incoming
precipitation, even if the impervious surfaces had not been in place. Impacts from additional
urbanization of the San Luis Obispo Creek watershed will need to be determined, as a result of
build-out according to the general plans for the City, County, and the California Polyt echnic State
University at San Luis Obispo (Cal Poly).
In addition to urbanization, there are other causes of riparian corridor degradation. The historic
presence of small dams in the upper watershed (near Stagecoach Road, which has been
removed, and the larger Reservoir Canyon facility) prevented large sediments (cobble and large
gravels) from being transported downstream. Naturally, these eroded sediments would have
continuously filled in the channels, but instead they became trapped behind the dams and filled in
the small reservoirs. The creek channels continued to erode the underlying material, and with
reduced incoming sediment to offset this erosion, the channels cut deeper into the landscape.
FLOOD MANAGEMENT CHALLENGES
Flood management continues to be a high priority for the City, but there are several important
barriers that can make management more difficult. Much of the creek corridor that runs through
the city along San Luis Obispo Creek and its tributaries is not owned by the City. Although the City
has some authority under the City’s Municipal Code for emergency removal of vegetation and
other debris, general maintenance of the creeks falls upon the owners of property adjacent to the
creek.
Additionally, the creek corridor is highly confined in areas, particularly through downtown, making
projects such as channel widening infeasible. Following the 1973 flood, the George S. Nolte &
Associates study, completed in 1977, identified proposed flood control projects, but few were
adopted because of the environmental effects associated with channel widening and other
alternatives (Questa Engineering Corporation 2003). Several areas of the city, including downtown
areas along San Luis Obispo Creek, the intersection of U.S. 101 and Los Osos Valley Road, the
Johnson Avenue railroad underpass, and areas surrounding Laguna Lake have been at a high
risk for frequent flooding (City of San Luis Obispo 2011).
To address these issues, large projects have been proposed to manage flood risk in the
increasingly urbanized city. One such proposed project is the Mid-Higuera Bypass Project, which
would increase conveyance capacity of San Luis Obispo Creek between Marsh Street and
Madonna Road. This area, downstream of the confluence of Stenner and San Luis Obispo Creeks,
has flooded and received extensive damage in some of the historical floods previously mentioned.
The planned removal of sediment and Arundo stands from San Luis Obispo Creek south of Los
Osos Valley Road will also serve to reduce local flood risk.
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CLIMATE-INFORMED FLOOD RISK MODELING
As part of the development of the Climate Adaptation and Safety Element, a climate-informed
flood risk modeling exercise was conducted to understand how changes in precipitation caused
by climate change are likely to affect the frequency and severity of large storm events (e.g., 100-
year storm event) and how these changes w ould affect the city’s existing flood plains. To read
details on the full Flood Risk Modeling Methodology, see Section 2.6 in Appendix A (Hazards
and Vulnerability Report).
Table 2 includes the modeling results for various size storm events in the San Luis Obispo Creek
watershed for the long-term period (2070-2099) under a high emissions scenario.
Table 2 Climate-induced Changes in Peak Stream Flow for the San Luis Obispo Creek
Watershed
Flood Event
(Return Interval)
Percent chance of
flood occurring in
any given year
Percent increase in peak stream flow
90th Percentile 50th Percentile
(median) 10th Percentile
500-Year 0.2% 122% 38% 4%
200-Year 0.5% 116% 38% 4%
100-Year 1% 110% 38% 4%
50-Year 2% 103% 37% 4%
20-Year 5% 93% 35% 3%
10-Year 10% 84% 33% 3%
5-Year 20% 73% 29% 3%
2-Year 50% 51% 28% 8%
1-Year 99% 64% 17% -31%
Source: cbec eco engineering 2021. The late century (2070-2099), RCP 8.5 scenario was used to determine flood
impacts.
As shown in Table 2, the 10th percentile results indicate an extremely dry scenario, which
experiences decreases in flow for events with less than a 2-year recurrence interval, while the
90th percentile results represent an extremely wet future scenario and results in peak flows more
than doubling for events that occur every 50 or more years. For flood events occurring more
rarely than every 2 years, flows are expected to increase across all scenarios including the 10th
percentile projection. Overall, the median projection represents the best available estimate at
this time for the San Luis Obispo Creek watershed for how peak flows are likely to change if
global GHG emissions maintain the high emissions scenario trajectory for the long-term period.
The climate-induced increases in flood magnitude are due to increases in precipitation intensity.
As the atmosphere warms, its ability to hold water vapor increases. While total annual
precipitation in different parts of the state is projected to increase, decrease, or stay the same
depending on the location, the trend of increasing rainfall within shorter periods of time
(increasing intensity) is projected to occur broadly (OPR et al. 2018a). In this way, even areas
that may become drier and experience water scarcity as a result of climate change may also
experience increased flood risk.
Based on California’s location next to the Pacific Ocean, the state is e xposed to the atmospheric
river (AR) phenomenon, a narrow corridor of concentrated moisture in the atmosphere.
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California is subject to precipitation from an AR that transports water vapor from as far south as
Hawaii to the state. The presence of the AR co ntributes to the frequency of “wet years” in the
state, when there is an above-average number of AR storms and above-average annual
precipitation. Projected peak stream flow increases are also greater for larger (less frequent)
flood events than for smaller ones, as a result of the watershed’s diminishing ability to absorb
increasingly high levels of rainfall. For example, following a long, dry summer, the land surface ,
soils, and vegetation will have a relatively high capacity to hold incoming rain and ver y little
stream flow may be generated from a notable amount of rainfall. In the mid -winter months, after
a series of precipitation events has passed through, the soils are relatively saturated and
generate runoff more quickly. For very large precipitation events, the capacity of the watershed
to absorb incoming rainfall can be quickly exceeded, causing large increases in stream flow
within the system. For the median scenario, peak flow rates are projected to increase from 17
percent to 38 percent for events that occur every year to every 500 years, on average, as show
in Table 2.
While research indicates that the frequency of large storm events do increase in these wet years,
the most severe flooding from ARs may not be in wet years (Swain et al. 2018). The largest
flooding impacts are caused by persistent storm sequences on sub -seasonal timescales (i.e.,
short time periods, typically 2 weeks to 3 months), which bring a significant fraction of annual
average precipitation over a brief period. These storm events are similar to the Great Flood
events of 1861–1862, which caused widespread damage throughout northern California (Swain
et al. 2016). Based on current climate modeling, the frequency of these large storm sequences
over short timeframes is projected to increase noticeably under the high emissions scenario. It
is estimated that a storm similar in magnitude to the Great Flood events is more likely than not
to occur at least once between 2018 and 2060 (Swain et al. 2018).
Although annual precipitation is anticipated to increase in the city and the larger central coast
region, California’s climate oscillates between extremely dry and extremely wet periods with
annual precipitation varying widely from year to year. Climate change is anticipated to
exacerbate these seasonal extremes with dry periods becoming dryer and wet periods becoming
wetter (OPR et al. 2018b:19). As a result, the frequency and severity of large storm e vents are
anticipated to increase as well. These oscillations between extremely dry and ex tremely wet
periods, which have occurred historically in the state, are anticipated to become more severe
with rapid shifts from dry to wet periods known as “whiplash events” (Swain et al. 2016). As
Swain et al. note in their research, the recent 2012 –2016 drought followed by the 2016–2017
flood events throughout the state serve as a good example of the type of whiplash events that
will occur more frequently over the next century. These types of events are estimated to increase
by approximately 100 percent in southern California, with increases in frequency occurring
largely after 2050 (Swain et al. 2016).
FUTURE FLOOD MAPPING RESULTS
Based on hydraulic modeling discussed above, future floodplain maps were generated to
understand how changes in precipitation for the 10-year, 50-year, and 100-year storm events
would impact the city as shown in Figures 3 through 11. Additional modeling for the 10-year, 50-
year, 100-year, and 500-year storm events are included in the appendix (Detailed Flood Mapping
Results) of the Hazards and Vulnerabilities Report (Appendix A). Figures 4 through 12 show the
generated depth maps for historic and future (long-term high emissions [RCP 8.5] scenario)
conditions for the 10-year (Q10) and 100-year (Q100) events within the San Luis Obispo Creek
– Stenner Creek and San Luis Obispo Creek – Prefumo Creek confluence areas. These figures
provide an illustration of the future extent of flood plains in the San Luis Obispo Creek watershed.
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However, there are limitations preventing these maps from being used for more detailed or more
absolute flood extent delineations for historic and future conditi ons. One main limitation is the
reliance upon hydraulic models that are almost two decades old and do not cover all areas of
the city as well as an uncertain range of possibilities for future precipitation and future global
emissions trends during the late-century period. However, the mapping exercise is useful for
indicating the locations and extents of relative flood impacts that may reasonably be expected
to occur due to climate change under the late-century high emissions scenario.
To further understand relative flood impacts, the hydraulic model domain was di vided into nine
analysis regions where changes in inundated area in acres and average depth on the floodplain
(ft) were compared between historic and future conditions for each flood event. To dete rmine
these statistics for floodplain areas, the regions within the creek channels and Laguna Lake were
removed from the analysis.
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Source: cbec eco engineering 2021.
Draft Figure 3 Flood Depth: Full Extent - Q100 (Historic)
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Source: cbec eco engineering 2021
Draft Figure 4 Flood Depth: SLO-Stenner - Q10 (Historic)
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Source: cbec eco engineering 2021
Draft Figure 5 Flood Depth: SLO-Stenner - Q10 (Future 2070-2099 – RCP 8.5)
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Source: cbec eco-engineering 2021.
Draft Figure 6 Flood Depth: SLO-Stenner - Q100 (Historic)
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Source: cbec eco-engineering 2021.
Draft Figure 7 Flood Depth: SLO-Stenner - Q100 (Future 2070-2099 – RCP 8.5)
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Source: cbec eco-engineering 2021.
Draft Figure 8 Flood Depth: SLO-Prefumo - Q10 (Historic)
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Source: cbec eco-engineering 2021.
Draft Figure 9 Flood Depth: SLO-Prefumo - Q10 (Future 2070-2099 – RCP 8.5)
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Source: cbec eco-engineering 2021.
Draft Figure 10 Flood Depth: SLO-Prefumo - Q100 (Historic)
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Source: cbec eco-engineering 2021.
Draft Figure 11 Flood Depth: SLO-Prefumo - Q100 (Future 2070–2099 – RCP 8.5)
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FLOODING POLICIES
Policy FL-3.1: CLIMATE-INFORMED FLOOD MANAGEMENT
The City shall incorporate the climate-informed flood risk modelling in flood management plans,
programs, and procedures.
POLICY FL-3.2: FLOOD PROTECTION FOR NEW DEVELOPMENT
The City shall ensure that all new development adheres to all provisions in Chapter 17.78 “Flo od
Damage Prevention” in the City’s Municipal Code and update the provisions accordingly to
remain consistent with any future federal, state, and loca l regulatory requirements.
POLICY FL-3.3: FLOOD PROTECTION FOR
EXISTING DEVELOPMENT
The City shall continue identification and
mapping of areas that are at increased flood
risk form large storm events using the climate-
informed flood risk modeling that was
developed as part of the City’s climate change
vulnerability assessment. The City should
research and develop flood damage
prevention measures that can be applied to
existing properties that will be at increased
flood risk due to climate change.
Policy FL-3.4: FLOODING AND POST-
WILDFIRE DEBRIS FLOW
The City shall conduct a detailed assessment to identify key impact areas in the city from a post-
wildfire debris flow scenario and the implications this scenario would have on stormwater runoff
during larger storm events. Develop a set of pre-disaster mitigation measures to be implemented
to help mitigate impacts from post-wildfire debris flow events. Mitigation measures could include:
• rapid reforestation and stabilization of wildfire-affected areas susceptible to debris flow
runoff to stabilize soils;
• communication and coordination with residents and businesses located within potential
impact areas from post-wildfire debris flow events; and
• development of analysis techniques to predict debris flow events based on rainfall and
moisture conditions.
POLICY FL-3.5: A RESILIENT FLOOD MANAGEMENT SYSTEM
The City shall explore opportunities to add redundancy to the city’s existing stormwater and flood
management systems to mitigate impacts from increased storm intensities, as needed. To
provide co-benefits to the SLO community, design flood management system redundanc ies to
serve multiple purposes that add value to the community (e.g., detention basins that serve as
Green Infrastructure: Bioswale
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parks or recreation areas). Resilient flood management projects should be prioritized in locations
of the city that are the most vulnerable.
Policy FL-3.6: REGIONAL COORDINATION FOR FLOOD CONTROL
The City shall continue to coordinate with regional partners (e.g., San Luis Obispo County, Cal
Poly San Luis Obispo, Caltrans) on flood preparedness and flood management initiatives.
FLOODING PROGRAMS
Program FL-3.7: WATERWAY MANAGEMENT PLAN
The City shall work with County to update the Waterway Management Plan to incorporate the
climate-informed flood risk modeling that was developed as part of the City’s Hazard and
Vulnerability Assessment. The City will encourage the County to include the following
components in the updated Waterway Management Plan:
• Incorporate future changes in precipitation patterns into the City’s Drainage Design
Manual to ensure that future development in the city can properly accommodate changes
in runoff from small and large storm events caused by climate change.
• Incorporate climate-informed flood risk modeling in all flood management-related capital
improvement projects in the Waterway Management Plan.
• Develop strategy to offset the increase in stormwater
runoff from existing residential and nonresidential land
uses from small storm events through green
infrastructure to help offset climate impacts on the City's
stormwater management system from climate change.
Prioritize green infrastructure design improvements,
including rain gardens, rainwater catchment barrels,
green stormwater infrastructure, bio-swales, detentions
basins, permeable parking lots, and permeable
pavement.
• Identify critical bridges and roadways (e.g., high-
volume roadways, key evacuation routes) and prioritize
upgrades to flood managent and drainange
infrastructure associated with these roadways to
account for future increases in large storm events.
Identify anthropogenic bank protection features that
could lead to flooding through channel constriction and
mitigate those structures (e.g., rock gabion baskets, stacked concrete sack walls).
• Identify riparian corridors and floodplains particularly suited for water retention (e.g. is
suitable to receive flood waters, can slow down in-channel water through) and prioritize
conservation and restoration projects on these areas to restore and retain natural
floodplain function and slow in-channel velocity with vegetation.
Green Infrastructure Definition
“Green infrastructure” encompasses
natural features, such as forests and
wetlands, that provide similar or
complementary flood-management
benefits as engineered
infrastructure. While engineered
infrastructure can degrade rivers and
the values they provide, green
infrastructure tends to support a
diverse array of other benefits. A
sustainable and resilient approach to
flood-risk management will deploy a
mix of green and engineered
infrastructure solutions, tailored to
specific challenges and objectives
(The Nature Conservancy 2014).
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Program FL-3.8 FLOOD DAMAGE PREVENTION
Update the provisions in Chapter 17.78 “Flood Damage Prevention” to incorporate climate risk
and information from the updated Waterway Management Plan.
Program FL-3.9: SUSTAINABLE FLOOD MANAGEMENT AND OPEN SPACE
Develop a program to work with public and private landowners upstream of waterways passing
through the city (e.g., Stenner Creek, San Luis Obispo Creek) to manage stormwater runoff
through sustainable land conservation practices (e.g., conservation easements) that achieve
multiple objectives including habitat restoration, land conservation, carbon farming,
reconnection/enhancement of floodplain areas and vegetation management, with a focus on
strategies that will reduce current and future flood risk.
Program FL-3.10: URBAN CREEKS VEGETATION MANAGEMENT PLAN
Develop Urban Creeks Vegetation Management Plan to address excessive and noxious
vegetation growth and remove dead material to prevent debris jams and reduce likelihood of
flooding in and around the City and integrate as an additional section in the updated Waterway
Management Plan.
PROGRAM FL-3.11: FLOOD-PREPARED NEIGHBORHOODS PROGRAM
Work with the San Luis Obispo County Office of Emergency Services, community organizations,
and regional partners to develop neighborhood readiness plans for areas of the city that are at
current and future risk from flooding events. The City should prioritize planning efforts in
neighborhoods that are the most vulnerable, and ensure additional supports are available for
community members to participate in the planning process and invest in flood resilience.
Program FL-3.12: COMMUNITY-DRIVEN FLOOD EDUCATION
Continue to work with the San Luis Obispo County Office of Emergency Service s to provide
accurate and readily available flood risk information through the County Ready SLO and City
Prepare SLO websites and resources and integrate future flood risk and climate -related flood
impacts into County Ready SLO and City Prepare SLO materials. Creative community-driven
flood risk and resilience workshops should be developed to build awareness with hard-to-reach
populations and high-risk neighborhoods. These workshops could occur through collaboration
with the County of San Luis Obispo Zone 9 Flood Control and Watershed Protection District.
Program FL-3.13 FLOOD WARNING MONITORING SYSTEM
Explore the feasibility, costs, and benefits of developing a dedicated early warning flood
monitoring system, or incorporating early flood warning into existing alert and notification
systems, in coordination with regional partners to provide alerts to residents and visitors in the
city during large storm events. Ensure that such a program provides benefits to the most
vulnerable members of the region, including persons experiencing homelessness and mobile
home communities.
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4. Extreme Heat
OVERVIEW
Heat is emerging as a critical hazard in San Luis Obispo. While the city generally has a mild,
Mediterranean climate, recent observed extreme heat events and a projected increase of
extreme heat events mean that heat is increasingly a public safety issue.
Although the city has not historically experienced many extreme heat conditions, the city is likely
to experience increased sensitivity to extreme temperatures because residents are not
acclimatized to or prepared for extreme heat conditions, even if increases are relatively mild
compared to other parts of the state. Extreme heat events are described in this section in terms
of their intensity (i.e., average maximum temperature), frequency (i.e., how often they occur),
time of year in which they occur, and duration (total number of consecutive extreme heat days).
Figure 12 includes the average annual maximum and minimum temperatures for the city from
1926 through 2018.
Sources: Cal Poly 2020.
Draft Figure 12 Average Annual Maximum and Minimum Temperatures in the City (1926-
2018)
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CLIMATE CHANGE AND EXTREME HEAT
As shown in Table 3, both annual maximum and minimum are projected to increase throughout
the 21st century. The average annual maximum temperature in the city is projected to increase
to 71.6°F in the near-term and 73.1°F in the midterm under the high emissions scenario. The
average annual maximum temperature is projected to increase to 73.1°F and 75.6 °F in the late-
century period under the medium and high emissions scenarios, respectively. The average
annual minimum temperature in the city is projected to increase to 48.7°F in the near-term and
49.7°F in the midterm under the high emissions scenario, a nd the late-century average annual
minimum temperature is projected to increase to 50.1°F and 52.7°F under the me dium and high
emissions scenarios, respectively (CEC 2019a). Increased temperatures in the city will influence
secondary climate effects, including extreme heat events, wildfire, and drought.
Table 3 Changes in Average Annual Temperature in City of San Luis Obispo
Geography Average Annual
Temperature
Historic Average
Annual
Temperature
(1961-1990)
Near-
Term
(2021-
2050)
Midterm
(2035-
2064)
Late-Century (2070-2099)
Medium
Emissions
High
Emissions
City of San
Luis
Obispo
Maximum
Temperature (°F)
68.4 71.6 73.1 73.1 75.6
Minimum
Temperature (°F)
45.7 48.7 49.7 50.1 52.7
San Luis
Obispo
County
Maximum
Temperature (°F)
69.8 72.9 74.3 74.7 77.3
Minimum
Temperature (°F)
42.2 45.4 46.6 46.9 49.8
Notes: °F = degrees Fahrenheit; RCP = Representative Concentration Pathway.
Source: CEC 2019a.
Figure 13 illustrates the projected change in average annual maximum temperature in the city
and in San Luis Obispo County (County) in the near -term and midterm periods under the high
emissions scenario and average a nnual maximum temperature in the late -century period under
both emissions scenarios. As shown in the Figure 13, the average annual maximum
temperature is expected to rise through the late -century period under both emissions
scenarios. As shown in Table 3, the County compared to the City, has had slightly higher
maximum and minimum temperatures historically with this trend continuing under both
emissions scenarios as temperatures continue to rise in both the City and the County. This
difference is also ref lected in Figure 13, which shows the city experiencing smaller increases
in annual average maximum temperatures compared to northern and eastern portions of the
County.
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and
downloaded from Cal-Adapt in 2021.
Draft Figure 13 Changes in Annual Average Temperature in San Luis Obispo County
through 2099
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Extreme Heat Events
The Cal-Adapt tool provides estimates of future instances of
extreme heat events. Extreme heat events include extreme
heat days and heat waves. Cal-Adapt defines an extreme
heat day as a day when the daily maximum temperature
exceeds the 98th historical percentile of daily maximum
temperatures based on observed data from 1961–1990
between April and October. Heat wave events are
characterized as periods of sustained extreme heat and are
defined by Cal-Adapt as four or more consecutive extreme
heat days.
The extreme heat threshold for the city is 89.6°F, meaning 98
percent of all recorded temperatures in this period were below 89.6°F. Historically (1961-1990),
the city experienced an average of four extreme heat days per year. As a result of rising
temperatures from climate change, the city is projected to experience up to 7 extreme heats
days annually in the near-term and 10 extreme heat days annually in the midterm under the high
emissions scenario. In the late-century period, the city is projected to experience up to 10
extreme heat days annually under the medium emissions scenario and 18 extreme hea t days
annually under the high emissions scenario (CEC 2019b). As shown in Table 4, the number of
extreme heat days is already increasing from historic averages and will continue to increase
under both emissions scenarios. The city is beginning to experien ce increases in extreme heat
with a record high temperature of 117°F being set on September 6, 2020 (NOAA 2021).
Table 4 Changes in Extreme Heat Events in City of San Luis Obispo
Annual Averages
Historic Annual
Averages (1961-
1990)
Near-
Term
(2021-
2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Medium
Emissions
High
Emissions
Number of Extreme Heat
Days
4 7 10 10 18
Number of Heat Waves 0.2 0.3 0.4 0.4 1.3
Number of Days in Longest
Stretch of Consecutive
Extreme Heat Days
2.6 2.8 3 3.4 4.6
Notes: RCP = Representative Concentration Pathway; Extreme Heat Day = day with maximum temperature
above 89.6°F; Heat Wave = four or more consecutive extreme heat days
Source: CEC 2019b.
While heat waves have historically been infrequent in the city, with a h istorical average of less
than one heat wave annually, climate change is expected to increase the frequency of heat
waves. Under the high emissions scenario, the city is projected to still experience less than one
heat wave per year in the near-term and in the midterm. In the long term, the city is projected to
experience less than one heat wave per year under the medium emissions scenario and 1.3 heat
waves per year under the high emissions scenarios.
The average number of days in the longest stretch of consecutive extreme heat days per year is
also projected to increase. Historically, the longest stretch of consecutive extreme heat days lasted
for an average duration of approximately two-and-a-half days. The longest stretch of consecutive
Extreme Heat Definitions
for City of San Luis Obispo
Extreme Heat Day = Day
with maximum temperature
above 89.6°F
Heat Wave = Four or more
consecutive Extreme Heat
Days
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extreme heat days is projected to increase only slightly in the near-term and 3 days in the midterm
under the high emissions scenario. In the late century, the duration is projected to increase to an
average of 3.4 days under the medium emissions scenario and 4.6 days under the high emissions
scenario (CEC 2019b). The timing of extreme heat days is also projected to change over the 21st
century with more extreme heat days and heat wave events occurring earlier in the year (April
through May) and more severe events occurring in the historically hot months of September and
October (CEC 2019b). The projected number of heat waves and number of days in the longest
stretch of consecutive extreme heat days is shown in Table 4.
URBAN HEAT ISLAND
The city’s urban land use patterns can intensify periods of extreme heat through the “urban heat
island” (UHI) effect. The UHI effect is the phenomenon of urban areas being significantly warmer
than surrounding rural areas because of human activity and land use patterns in the built
environment. Several factors contribute to the effect, with the primary cause being changes in
land surfaces (EPA 2008). The albedo of a surface is the measure of the ability to reflect or
absorb solar radiation, with darker surfaces having a lower albedo and absorbing more solar
radiation. As urban areas develop over time, resulting in the development of more land surfaces
with low albedos (e.g., asphalt pavement, dark building surfaces), more solar radiation is
absorbed in these materials causing increased ambient temperatures and warmer nighttime
temperatures. Another factor contributing to the UHI effect is the loss of evapotranspiration in
urban areas. Evapotranspiration, the movement of water to the air from sources such as t he soil,
plants, and bodies of water, reduces ambient air temperatures (EPA 2008). As cities grow and
often reduce the extent of available vegetation that contributes to evapotranspiration, UHI effects
increase. Additionally, waste heat from human activities involving machinery (e.g., vehicle traffic,
using air conditioning, industrial activity) can also contribute to the UHI effect, with excess heat
absorbed by surrounding surfaces (Sailor 2011; Zhu et al. 2017).
ENVIRONMENTAL JUSTICE AND EXTREME HEAT
Alongside populations with health sensitivities, residents with specific sociodemographic
characteristics are at increased sensitivity to extreme heat events (CDC 2019). Research has
found that low-income residents spend a larger proportion of their income on utilities, including
electricity use for cooling, with these residents being disproportionately affected during extreme
heat events (Voelkel et al. 2018). Additionally, research has found that low -income
neighborhoods can often have less tree coverage and park space, further contributing to the
disproportionate impact on low-income residents (Zhu and Zhang 2008). Decreased access to
transportation services can further increase exposure and health risks from extreme heat events
for the unhoused community (Ramin and Svoboda 2009). Unhoused individuals are also at
increased risk from extreme heat events with, generally, less access to places to cool off and
healthcare resources during these events. Figure 16 shows the location of low-income areas in
the city, based on SLOCOG regional definition of low-income. The map shows urban heat island
hotspots and areas where average income level is less than 80 percent of the region’s average
median income.
The Margarita Avenue Neighborhood (Census Tract 111.03) is an area of the city with a
particularly vulnerable population in regard to extreme heat, Figure 14. This area includes a high
percentage of elderly and disabled residents, a high p ercentage of residents experiencing
linguistic isolation, and 50 percent of residents earning less than 200 percent of the federal
poverty level. This census tract also is located in a portion of the city that experiences a more
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intense severity of the urban heat island effect, resulting in potentially disproportionate impacts
on this population during extreme heat events. The West of South Higuera neighborhood
(Census Tract 115.01) also stands out as a particularly vulnerable to extreme heat, with the area
also near urban heat island hotspots and includes a high percentage of elderly and disabled
residents.
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Source: Data received and downloaded from City of San Luis Obispo and the Trust for Public Land.
Draft Figure 14 Urban Heat Island Effect and Tree Cover in the City
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EXTREME HEAT POLICIES
Policy HE-4.1: CLIMATE-SMART URBAN HEAT MITIGATION
The City shall equitably mitigate the effects of extreme heat in outdoor environments.
Policy HE-4.2: EQUITABLE ACCESS TO SAFE INDOOR SPACES
The City shall support equitable access to climate controlled indoor spaces.
Policy HE-4.3: GREEN AND HEALTHY BUILDINGS
The City shall support fuel switching retrofits (from fossil fuel to high-efficiency electric
appliances), energy efficiency retrofits, and distributed energy resources as low carbon solutions
to create safe, cool, and healthy buildings and consider programs and projects that support these
retrofits as critical to maintaining community safety and to supporting disaster preparedness.
EXTREME HEAT PROGRAMS
PROGRAM HE-4.4: URBAN HEAT ISLAND MITIGATION PROGRAM
Develop and implement a program to mitigate the projected increasing impacts from the urban
heat island effect. This program should include:
• A strategy to maintain and enhance the city’s urban tree canopy and other vegetative
features to help reduce the urban heat island effect while accounting for the effect of
shifting average minimum and maximum temperatures on sensitive tree species and
vegetation.
• A “cool pavement” pilot to reduce the urban heat island effect being generated from the
city’s pavement surfaces, focusing on large surface parking lots and urban heat island
hotspots. Should the pilot prove effective, consider scaling the program , including
through the adoption of new standards for new development projects, as appropriate, to
use high-albedo or cool pavements for surface parking lots.
• A Climate-Smart Green Infrastructure Strategy with regular updates to the City’s Capital
Improvement Program and Foundational Action Natural Solutions 2.1 in the City’s
Climate Action Plan which focuses on preparing the City’s first Community Forest Plan
by 2022 and planting and maintaining 10,000 new trees by 2035.
• A review of and update to Section 12.38.090 “Landscaping Standards” in the City’s
Municipal Code and other design guidelines to incorporate strategies to increase shading
of buildings and parking lots to mitigate the urban heat island effect while also ensuring
that the updated landscaping standards are aligned with recommended fire wise plant
species.
• A review of and update to City development standards, where appropriate, to include
building and site design features that mitigate the urban heat island effect including
reflective roofing, solar carports.
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PROGRAM HE-4.5: CLIMATE-SMART URBAN TREE CANOPY
Conduct analysis and incorporate climate change considerations into the City’s Community
Forest Plan and update the City’s Street Trees Master List to prepare for increases in minimum
and maximum temperatures and extreme heat events and corresponding drought and fire risk,
identifying which trees will be most vulnerable to climate impacts and which specie s will thrive
during future increases in temperature. Ensure that the updated Street Trees Master List does
not include high water use trees or highly com bustible trees. Emphasize the planting and care
of appropriate climate-ready trees in locations where they will have the greatest chances of
success in environmental conditions that are predicted to become more challenging (i.e., “right
tree, right place”). Communicate the results of the analysis to help community members prepare
for impacts on trees on private property.
Give high priority to water conservation in all urban forest -related actions. This could include
species selection, irrigation method and time-of-day recommendations, mulching, co-location
with natural drainages and stormwater runoff, etc.
Lumber from removed trees should be used in ways that store carbon indefinitely instead of
releasing it back into the atmosphere, and these uses should be publicized to build awareness
and support for climate action.
Program HE-4.6: COMMUNITY COOL ZONES NETWORK
Work with community organizations, faith -based organizations, businesses, local government
entities in SLO County, and other institutions to develop a Community Cool Zone Network
comprised of air-conditioned spaces conveniently located throughout the city that can be opened
during heat wave events to help prevent heat -related illness for vulnerable populations (e.g.,
elderly, youth, homeless, residents without air conditioning). Support network participants to
conduct energy efficiency and building decarbonization improvements consistent with the City’s
Climate Action Plan. Prioritize opening cool zone locations in areas with identified heat -
vulnerable populations and disadvantaged communities and consider co-locating with
Resilience Hubs. Assess feasibility and efficacy of providing transportation options to the cooling
network location to elderly residents and transit-dependent populations.
PROGRAM HE-4.7: GREEN AND HEALTHY BUILDINGS PROGRAM
Expand the City’s Green and Healthy Buildings Program (the existing building retrofit program
focused on electrification per the 2020 Climate Action Plan) to include climate resilience retrofit
features to help residents prepare for the impacts of climate change (e.g., extreme heat,
wildfires, and wildfire smoke). This work should include conducting a gap analysis to identify
portions of the city’s housing stock that are not equipped with air-conditioning or other cooling
systems to address the projected increases in temperature and extreme heat events. As part of
the building retrofit program, include proactive efforts (i.e., incentives, matching funds) to retrofit
or assist with retrofitting the identified housing stock with climate resiliency features including:
• Adequate climate control equipment (e.g., heat pump HVAC-systems) with air filtration
systems.
• Weatherization and energy efficiency improvements.
• Distributed energy resources (e.g., rooftop solar, battery storage, electric vehicle battery
to building equipment, etc.) to support grid-independent operation and to offset utility
energy costs.
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• Home hardening improvements to protect against wildfire.
PROGRAM HE-4.8: EXTREME HEAT AND EMERGENCY PREPAREDNESS
As part of the next update of the City’s Emergency Operations Plan, incorporate a protocol for
emergency operations during extreme heat events in the city. Identify extreme heat thresholds
which, if exceeded, would trigger the opening of cooling centers in the city as well as emergency
response efforts from appropriate City departments (e.g., Police Department, Fire Department,
Parks & Recreation). Coordinate emergency response efforts in Program HE-4.9 regarding heat-
related community outreach with this strategy.
PROGRAM HE-4.9: EQUITABLE COMMUNITY OUTREACH FOR EXTREME HEAT
Use information from the Hazards and Vulnerabilities Report that identifies areas in the City with
vulnerable populations (e.g., linguistically isolated households, elderly, youth, homeless ,
individuals with chronic health conditions) to conduct targeted outreach to these neighborhoods
and areas in the City. Increase education and training opportunities for residents to prepare for
extreme heat events, with a prioritization on participation from vulnerable populations and
businesses and institutions that house and/or support vulnerable populations. Work with
community organizations and the San Luis Obispo County Health Department to provide
additional resources and training to staff working with elderly populations on how to prevent
health-related heat impacts (Paterson et al. 2014). Work with community organ izations and
schools to help mitigate the impacts of extreme heat and heat wave events on youth. Educate
and train staff working with youth populations on how to prevent health -related impacts from
extreme heat. Continually assess the effectiveness of the City’s public information and education
efforts during heat wave events.
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5. Fire
OVERVIEW
A wildfire is defined as an uncontrolled fire spreading through vegetative fuels that poses a threat
to life and/or property (San Luis Obispo County 2019). Wildfires can be ignited by natural events,
such as lightning strikes, or can be caused by damaged infrastructure (e.g., downed power lines)
or human activities (e.g., campfires, arson). Wildfires can move quickly, casting embers into
downwind areas and spreading to developed areas, putting human lives and properties at risk.
Three factors that contribute significantly to wildfire behavior are topography, fuel, and weather:
Topography—An area’s terrain and slope affect its susceptibility to wildfire spread. Both fire
intensity and the rate of spread increase as slope increases because heat from a fire tends to
rise through convection. For this reason, wildfires tend to spread more slowly downhill. The
arrangement of vegetation on a hillside can also contribute to increased or decreased fire activity
on slopes.
Fuel—The type, condition, and volume of fuel material are key factors that influence wildfire
behavior. Fuel sources are diverse and can include dead vegetative matter, live trees, brush,
and cured grasses. Buildings and other structures, such as homes, can also be sources of fuel.
Certain types of plants are more susceptible to burning or will burn with greater intensity, and
dead, dry plant matter tends to burn more easily than living plant matter. Thus, fire risk is
increased significantly during periods of prolonged drought. The density of vegetation increases
the amount of combustible material available, also called the fuel load.
Weather—Factors such as temperature, humidity, wind, and the occurrence of lightning affect
the potential for wildfire and its spread. High temperatures and l ow humidity can dry out wildfire
fuels, creating a situation in which fuel will ignite more readily and burn more intensely. Thus,
wildfire risk increases during periods of drought. Wind is one of the most significant weather
factors in the spread of wildfires. Higher wind speeds lead to faster wildfire spread and,
oftentimes, greater fire intensity.
Environmental and climatic conditions in and around the city influence the frequency and
magnitude of wildfires. The city often experiences high -wind events, such as the Santa Lucia
winds, which originate inland and flow westward during the late summer and early fall, counter
to the prevailing westerly winds that occur throughout much of the year. Santa Lucia winds
contain little humidity, and summers in the city are hot and dry, with precipitation primarily
occurring in the winter months. Thus, the combination of the relatively hot, dry Santa Lucia winds
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occurring at a time when vegetation in the County and the city is particularly dry following the
summer months can contribute to the ignition and spread of la rge wildfires. Periods of low
relative humidity, when dead trees and vegetation cannot absorb moisture from the air, can also
increase the risk of wildfires (City of San Luis Obispo 2011).
The risk of wildfires and subsequent impacts to property and life is greatest at the wildland-urban
interface (WUI), which is where urban development borders wildland fuels. Wildfire risk is
compounded in areas of the WUI that are also located in or near High or Very High Fire Hazard
Severity Zones. Figure 18 includes CAL FIRE designated Fire Hazard Severity Zones in and
surrounding the city. Portions of southwestern and northeastern parts of the city are located in
or near a Very High Fire Hazard Severity Zones, and many of these portions of the city overlap
with the WUI. Locations identified by CAL FIRE as Hazard Severity Zones for the City and
County are identified in Appendix G (Cal Fire San Luis Obispo County Fire Hazard Severity Zone
Map). Beyond these areas of the city, the risk of urban fires decreases, with most of the areas
surrounding the city located in a Moderate Fire Hazard Severity Zone.
Figure 19 shows the locations of fires that have occurred within 10 miles of the city between
1900 and 2020; four fires have occurred within city boundaries. Between 1900 and 2018, 490
wildfires have been recorded in the County (San Luis Obispo County 2019a). Notable fires that
have occurred in the County include the Weferling fire (1960), the Las Pilitas fire (1985), the
Chispa fire (1989), the Highway 41 fire (1994), the Highway 58 fire (1996), the Logan fire (1997),
and the Chimney fire (2016). In total, these fires burned approximately 400,000 acres, destroyed
numerous structures, and cost millions of dollars to suppress (City of San Luis Obispo 2019).
The Las Pilitas fire burned 75,000 acres and burned within city limits, damaging a number of
structures (City of San Luis Obispo 2011). The 1994 Highway 41 fire burned more than 50,000
acres close to the city’s northern boundary and destroyed 42 homes, 61 other structures, and
91 vehicles (San Luis Obispo County 2019).
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Source: San Luis Obispo County 2019a.
Draft Figure 15 Wildfire Hazard Severity Zones in and Surrounding the City of San Luis
Obispo with Critical Facilities
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Sources: Data downloaded from CAL FIRE in 2020.
Draft Figure 16 Wildfire Perimeters for Wildfires within 10 Miles of the City of San Luis
Obispo (1900–2020)
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Wildfire Management
The City’s Fire Department is the main agency responsible for wildfire response, management,
and mitigation in the city, with many fires being addressed through mutual aid by both the City’s
Fire Department and CAL FIRE. Several agencies, including the Cou nty, provide support to
incorporated areas, including the City, during wildfire events. Supporting agencies, such as
CAL FIRE, are also available to mobilize during fire response if needed. In addition to having the
authority to declare local emergencies, the County can provide support for evacuations, shelter,
and other forms of assistance for municipalities, including the City (San Luis Ob ispo County
2016). The City can also declare a disaster declaration through the City’s Disaster Council,
absent the County. Because fire risk is highest for regions of the city within the WUI, the City
has produced detailed maps of these regions, indicating evacuation routes and other critical
information for responders. Locations identified by CAL FIRE as Hazard Severity Zones for the
City and County are identified in Appendix G (Cal Fire San Luis Obispo County Fire Hazard
Severity Zone Map). The City’s Community Wildfire Protection Plan serves as the primary
document for assessing wildfire risk in different areas in the city and helping to implement a
series of policies and strategies to reduce this risk, including:
Education – The goal of the education policies and strategies are to prepare response
organizations, communities, the public, and policy makers regarding app ropriate community
actions and interactions to reduce the unwanted impacts of fires in the WUI.
Fuel – The goal of the fuel policies and strategies are to mitigate the unwanted impacts of
wildfires on communities through proper vegetation management techni ques that reduce
hazardous fuels and the resulting wildfire intensity.
Planning – The goal of the planning policies and strategies are to mitigate the unwanted impacts
of wildfires on communities through community planning (including new resilient community
design, retrofitting existing communities, and efforts that support community recovery from the
impact of fire), response planning, evacuation planning, and preparedness planning for
responders, communities, individuals, animals, and livestock.
Response – The goal of the response policies and strategies are to mitigate the unwanted
impacts of wildfires on life, property, and resources by having an efficient and effective response
that includes properly trained personnel, appropriate equipment, and a community prepared to
take appropriate action or evacuation.
Ignition Resistance - The goal of the ignition resistance policies and strategies are to eliminate
or mitigate structural ignitions from radiant heat, flame contact, or embers from WUI fires.
Wildfire Smoke
While the city is at risk from the impacts of wildfires, the city and its residents are also susceptible
to impacts of smoke from wildfires in the coastal mountain ranges of central California and the
Los Padres National Forest to the east of the city. Wildfire smoke in the surrounding region and,
due to wind patterns, wildfires along the central coast in general, can greatly reduce air quality
in the city and cause public health impacts as well as impacts to tourism and normal community
functions. Community public health factors that can increase the impacts of wildfire smoke
include the prevalence of asthma in children and adults; chronic obstructive pulmonary disease;
hypertension; diabetes; obesity; percent of population 65 years of age and older; and indicators
of socioeconomic status, including poverty, income, and unemployment. Exposure to wildfire
smoke, particularly exposure to vulnerable populations, can result in worsening of respiratory
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symptoms, increased rates of cardiorespiratory emergency visits, hospitalizations, and even
death (Rappold et al. 2017). In the summer of 2020, wildfire smoke alerts were is sued for San
Luis Obispo County due to poor air quality caused by the Dolan Fire near Big Sur. Wildfire smoke
can also have impacts on the labor market and the economy in general, with air quality affecting
the ability of outdoor workers to perform their work and impact industries that operate in the open
air (e.g., wineries, recreation activities, sporting events) (Borgschulte et al. 2019).
Climate Change and Wildfires
The effects of climate change, including increased temperatures, and changes to precipit ation
patterns, will exacerbate many of the factors that contribute to wildfire risk. Recent research has
found that increases in global temperatures may be affecting wind patterns and increasing global
wind speeds, however these changes would not be experienced uniformly across geographies
in the future (Chen 2020). While the impact of climate change on wind speeds is still uncertain,
it is important to recognize this potential effect and how it may also contribute to wildfire risk in
the future.
Increased variability in precipitation may lead to wetter winters and increased vegetative growth
in the spring, and longer and hotter summer periods will lead to the drying of vegetative growth
and ultimately result in a greater amount of readily burned fuel for fires. This has already been
seen across the state in recent years, with the area burned by wildfires increasing in parallel with
rising air temperatures (OEHHA 2018). These factors, combined with the increasing frequency
and severity of intense wind conditions, will cause fires to spread rapidly and irregularly, making
it difficult to predict fires’ paths and effectively deploy fire suppression forces. Pacific Gas and
Electric (PG&E) also has several electrical transmission lines running through the city, which
carry significant potential fire risk (Figure 17).
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Draft Figure 17 PG&E Transmission Lines in the City of San Luis Obispo
Relative humidity is also an important fire-related weather factor; as humidity levels drop, the dry
air causes vegetation moisture levels to decrease, which consequently increases the likelihood
that plant material will ignite and burn. With an increase i n hotter and drier landscapes, humidity
levels may continue to drop and result in higher fuel loads, increasing the risk of wildfire
(Schwartz et al. 2015).
Given the city’s urban setting, with minor portions of the city in the VHFHSZ, the analysis for
future wildfire risk analyzes changes in wildfire risk at the County level to assess how larger
regional risks and potential impacts may affect the city. Using a statistical model based on
historical climate vegetation, population density, and large fire his tory, Cal-Adapt provides
projections for future annual mean acres burned within the County when wildfires do occur. Cal-
Adapt does not account for current or planned wildfire management projects. Table 5 and Figure
18 shows the projected change in average annual area burned within the County under low and
high emissions scenarios for the central population growth scenario at midterm and late -century
timescales. The total area burned annually by wildfire within the County is expected to rise 15
percent from the historic (1961–1990) annual average of 22,852 acres to 26,497 acres in the
near-term and increase in the midterm to 26,509 acres burned annually. In the late-century,
average annual area burned in the County is projected to increase to 26,509 acres and decrease
slightly to 24,382 acres under the low and high emissions scenarios, respectively (CEC 2019b).
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This reduction in annual average acres burned in the late-century period is noted in the research
conducted to develop the Cal-Adapt wildfire tool. As vegetation type and fuel amount, structure,
and continuity change in the future due to altered disturbance regimes (e.g., changes in the
frequency, seasonality, duration, extent and severity of wildfire and infestations by beetles and
other pathogens) and climate, future wildfire activity and its response to climatic variability may
reduce wildfire activity in some ecosystems (Westerling 2018).
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and
downloaded from Cal-Adapt in 2021.
Draft Figure 18 Projected change in average annual area burned within San Luis Obispo
County through 2099
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Importantly, Figure 18 illustrates that anticipated changes in wildfire impacts are not
homogenous across the County; for instance, the Santa Lucia Wilderness and the La Panza
Mountain range located in the southern central portions of the County will experience the larger
increases in average area burned over the 21st century under both emissions scenarios. While
these areas are outside of the city boundaries and jurisdiction, due to the regional characteristics
of wildfire impacts, wildfire events in these areas could affect th e city through secondary impacts
such as short-term and long-term wildfire evacuees, wildfire smoke, and impacts on the County’s
regional transportation network.
Table 5 Changes in Annual Average Area Burned in San Luis Obispo County
Average Annual Area
Burned
Historic Modeled1
Average Annual
Area Burned
(1961-1990)
Near-Term
(2021-
2050)
Midterm
(2035-
2064)
Late-Century (2070-2099)
Medium
Emissions High Emissions
Average Annual Area
Burned (acres) 22,852 26,497 26,509 26,509 24,382
Notes: RCP = Representative Concentration Pathway.
1 Observed historical average annual area burned data were not available from Cal-Adapt; the modeled historical
average annual area burned data under the medium emissions scenario was available and used as proxy data.
Source: CEC 2019d, hectares converted to acres
FIRE POLICIES
POLICY FI-5.1: REDUCE WILDFIRE RISK
The City shall reduce the risk of wildfires in city open spaces and in the wildland urban interface
through timely implementation of the City’s Community Wildfire Protection Plan and the
Vegetation Management Plan.
POLICY FI-5.2: FIRE-SMART LAND-USE PLANNING
The City shall minimize fire risk in land-use planning decisions. The City shall update local zoning
and subdivision codes to designate wildfire hazard overlay zones and associated conditional
use, site development standards, and design criteria to mitigate wildfire hazards and reduce
risks to new development within the overlay zones.
Promote the following risk reduction measures in future land use planning efforts in the city:
• Use wildfire risk analysis resources such as the CAL FIRE’s Fire and Resource
Assessment Program data in future housing site constraints analyses to ensure futu re land use
planning avoids locating new housing in high wildfire risk areas.
• Promote the use of clustered development patterns for subdivisions that require less fire
suppression resources and are easier to defend during wildfire events compared to large -lot
single family homes.
POLICY FI-5.3: FIRE-SMART NEW DEVELOPMENT
The City shall avoid locating future development projects in the wildland-urban interface or in
areas of the city located within a CAL FIRE designated High or Very High Severity Zones.
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The City shall only approve development when adequate fire suppression services and facilities
are available or will be made available concurrent with development, considering the setting,
type, intensity, and form of the proposed development . Ensure that new development projects
include adequate measures to minimize fire hazards while remaining in compliance with housing
laws regarding objective design standards and discretionary review.
Fire protection plans should address wildland fuel transition zones surrounding the development
and include the following components:
• Provisions for the maintenance of vegetation within the subdivision to reduce wildfire risk
• Requirements for hardening of structures to mitigate fire risk that meets or exceed the
California Building Code
• Landscaping and defensible space design around a proposed structure that reduces
wildfire risk.
POLICY FI-5.4: FIRE-SMART BUILDINGS AND HIGH OR VERY HIGH FIRE HAZARD SEVERITY
ZONES
The City shall reduce wildfire risk associated with new development by requiring all new
development located within any CAL FIRE design ated High or Very High Fire Hazard Severity
Zone to:
Meet or exceed the State’s Fire Safe Regulations (title 14, CCR, division 1.5, chapter 7,
subchapter 2, articles 1-5 commencing with section 1270) and Fire Hazard Reduction Around
Buildings and Structures Regulations (title 14, CCR, division 1.5, chapter 7, subchapter 3, article
3 commencing with section 1299.01).
Include designs to minimize pockets or peninsulas or islands of flammable vegetation within a
development.
Include additional access roads, where feasible, to ensure adequate access for emergency
equipment and civilian evacuation concurrently. All requirements and any deviations will be at
the discretion of the Fire Code Official.
Meet or exceed the California Building Code for Materials and Con struction Methods for Exterior
Wildfire Exposure (Title 24, part 2, Chapter 7A).
For all remodeled or rebuilt structures, require projects to meet current ignition resistance
construction codes included in the State’s Fire Safe Regulations.
POLICY FI-5.5: WILDFIRES AND CRITICAL FACILITIES
The City shall locate, when feasible, new essential public facilities outside of high fire risk areas,
including, but not limited to, hospitals and health care facilities, emergency shelters, emergency
command centers, and emergency communications facilities, or identifying construction
methods or other methods to minimize damage if these facilities are located in a State
Responsibility Area or Very High Fire Hazard Severity Zone.
POLICY FI-5.6 MAINTAIN FIRE FLOW
The City shall ensure adequate fire flow is maintained within the City limits through ongoing
maintenance, capital improvement infrastructure upgrades, and improvements required in
association with development projects.
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POLICY FI-5.7 FIRE SUPPRESSION INFRASTRUCURE RESILIENCY
The City shall maintain fire flow during scheduled and unscheduled power outages and
interruptions through incorporation of power source resiliency and redundancy within City water
supply, treatment, and distribution infrastructure.
POLICY FI-5.8: WILDFIRE AND PARKING MANAGEMENT
The City shall adopt an ordinance to restrict on-street parking in high wildfire risk areas in San
Luis Obispo during increased fire risk days to ensure full access for fire trucks and emergency
vehicles and to increase roadway accessibility during evacuation events. The City Fire
Department and other departments shall identify streets and neighborhoods that are at
increased wildfire risk using the CAL FIRE Fire Hazard Severity Zones, Wildland Urban Interface
Areas identified by the City, or another internal process. Conduct community outreach to
neighborhoods affected by the policy and provide detailed information on how and when the
parking restrictions will be implemented.
POLICY FI-5.9: CONCURRENCY OF FIRE PROTECTION SERVICES
The City shall ensure that adequate fire protection staffing, facilities, and equipment required, to
serve developments operating before, or in conjunction with development.
POLICY FI-5.10: CLIMATE-SMART FIRE PROTECTION
The City shall incorporate the most current climate science regarding wildfires into all future
reviews and updates to the City’s fire and wildfire related documents (e.g., community wildfire
protection plan).
POLICY FI-5.11: PROACTIVE COMMUNICATIONS ON FIRE RISKS AND PREVENTION
The City shall proactively communicate with the public about fire risks and prevention, including
information about:
• wildfire smoke health impacts and available mitigation strategies
• The “Ready, Set, Go!” wildfire preparedness program including defensible space, home
hardening, personal wildfire action planning, and evacuation actions.
• Public safety power shutoffs associated with high fire danger.
FIRE PROGRAMS
PROGRAM FI-5.12: IMPLEMENT THE COMMUNITY WILDFIRE PROTECTION PLAN
Continue to implement the City’s Community Wildfire Protection Plan (CWPP) to reduce wildfire
risk in the City’s wildland-urban interface including implementation of the CWPP Tactical Policy
Measures which focus on the four key policy areas of community education, fuels management,
planning, and emergency response preparedness on an ongoing basis. Update the CWPP,
every 5 years or sooner, to incorporate new best practices, funding opportunities, new legislation
regarding wildfire protection, and other wildfire protection planning resources.
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PROGRAM FI-5.13: IMPLEMENT THE VEGETATION MANAGEMENT PLAN
Continue to implement the City’s Vegetation Management Plan, conducting fuel reduction
projects at the 12 large open space lands included in the plan, using vegetation management
techniques appropriate for each open space including manual vegetation remova l; tree removal;
mechanical treatment, prescribed burning, livestock grazing, and chemical treatment. Update
the Vegetation Management Plan, as needed, to incorporate regulations regarding new best
practices, and new funding opportunities for vegetation ma nagement projects.
Meet with the yak tityu tityu yak tiłhini (Northern Chumash Tribe San Luis Obispo County and
Region (ytt Tribe)), Northern Chumash Tribal Council, and other tribal bodies on an annual basis,
or as needed to incorporate Traditional Ecological Knowledge approaches to vegetation
management in the City where appropriate.
Work with private property owners, San Luis Obispo County, and Caltrans to conduct roadside
vegetation clearance along public and private roadways in Very High Fire Hazard Severity Zones
in the city. Ensure that fuel reductions provide an appropriate fuel buffer for evacuees should
these roadways become congested during an emergency incident.
Develop an Urban Creek Vegetation Management Plan as part of the Waterway Management
Plan update. The plan shall set forth a holistic vision to address excessive and noxious
vegetation and dead material in the creeks and waterways in San Luis Obispo and surrounding
areas. Work with private property owners and San Luis Obispo County to review and conduct
vegetation management to ensure dead trees and vegetation are reduced to prevent fire from
spreading to adjacent lands.
PROGRAM FI-5.14: WILDFIRE IGNITION SOURCE REDUCTION PROGRAM
The City will work to reduce wildfire ignition sources within the City’s open space and creek
systems by supporting policy and exploring fire code amendments that restricts public access to
hazardous fire areas during critical weather events.
PROGRAM FI-5.15: WILDLAND-URBAN-INTERFACE DEFENSIBLE SPACE AND HOME
HARDENING PROGRAM
Implement a program to assist homeowners, landlords, and business owners in improving the
defensible space for structures in or near the very high fire hazard severity zones. The program
will serve to connect participants to contractors with experience in developing or improving home
hardening improvements (e.g., fire-safe building materials, fire resistant home vent upgrades ).
The program will seek funding to supplement the costs associated with defensible space
improvements, prioritizing low-income participants and elderly or disabled residents who would
not be able to implement defensible space improvements on their own. The program would be
developed and administered in close collaboration with the City’s Fire Department and CAL FIRE
to ensure appropriate standards for defensible space are implemented as part of the program
consistent with AB 3074 (“Fire Prevention: wildfire risk : defensible space: ember-resistant
zones”).
PROGRAM FI-5.16: RESIDENT INFORMATION AND TRAINING ON FIRE HAZARDS
The City will inform homeowners and tenants about local fire hazards, appropriate responses to
fire, and ways to prevent loss, including home improvements that can reduce the impact of f ire.
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The City will promote the efforts of the Fire Safe Council.
The City will continue hosting community preparedness sessions and workshops as effective
preparation resources for residents to aid themselves when needs exceed the availability of
professional emergency response workers.
The City will support education programs in the lower grades, using displays and demonstrations
to inform young children about fire safety, and in secondary schools, demonstrating the dynamic
aspects of fire, including major factors contributing to fire hazard and the relationship of fire to
the natural ecology. Fire prevention and evacuation lessons will be included in each program.
PROGRAM FI-5.17: WILDFIRE SMOKE PROTECTION OUTREACH STRATEGY
Work with the San Luis Obispo Air Pollution Control District to ensure residents are educated on
how to protect themselves and their homes from wildfire smoke impacts. Prioritize outreach
campaigns to populations who are vulnerable to poor air quality and those who work with the
population (e.g., elderly care nurses and assistances, teachers), conducting educational events
at convenient locations for these residents.
The outreach strategy should also focus on supporting employers to maintain compliance with
California Code of Regulations, Title 8, Section 5141.1, which applies to most outdoor
workplaces where the current Air Quality Index (current AQI) for airborne particulate matter is
2.5 micrometers or smaller is 151 or greater, and where employers should reasonably anticipate
that employees could be exposed to wildfire smoke. Compliance requirements and training
instructions are included in California Code of Regulations, Title 8, Section 5141.1.
PROGRAM FI-5.18: SUPPORT COMMUNITY RESILIENCE DURING PUBLIC SAFETY POWER
SHUTOFFS
Through the City’s Community Development Department, proactively provide information for the
installation of battery storage systems for existing residential and non-residential developments,
prioritizing opportunities for essential services such as hospitals, grocery stores, pharmacies,
and other essential businesses.
Develop a streamlined permitting process, including appropriate CEQA exemptions, for the
installation of small- and large-scale battery storage systems in existing residential and
nonresidential development as well as providing applicants information on available financing
options. Prioritize resource allocation to residents facing additional risks from Public Safety
Power Shutoffs (PSPSs) including the elderly and disabled. Explore the viability of vehicle-to-
building (V2B) technologies that can provide resilience by using the energy stored in PEV batters
to power loads inside residential, commercial, or public buildings.
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6. Earthquakes and other Geologic Hazards
OVERVIEW
Geologic conditions encompass the form of the ground surface, the composition and character
of soils, rocks, and water at the ground surface and below, and the long -term movement of the
Earth’s crust and mantle. These conditions determine the stability of the ground at a site, and
how that site will respond to changes caused by people and by the natural forces of earthquakes
and weather.
The frequency and strength of
earthquakes depend on the number and
type of faults that pass through an area.
The city is in a geologically complex and
seismically active region. Seismic
conditions here have the potential to
result in significant harm to people and
property. Some fault locations and
characteristics have been identified,
however, recent earthquakes in California
have shown that not all active faults are
revealed by surface features. Safety
precautions should be based on known
factors, as well as an awareness of the
limitations to current knowledge. This
Element must consider two of the direct
effects of an earthquake: rupture of the
ground surface along a fault, and ground
shaking that results from fault movement.
Other hazards associated with earthquakes are settlement, liquefaction, landslide, collapse of
pipes and structures, fires, and flooding from dam failure.
Numerous faults transect valleys and hillside areas in San
Luis Obispo.
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Surface Rupture
Surface rupture refers to the top of the ground moving unevenly along a fault: one side moves
horizontally, vertically, or both, with respect to the other side. It typically occurs within an area of
linear traces along previous ruptures, which mark a fault zone, and often in concert with
movement on adjacent or intersecting faults. Rupture of the ground surface along a fault trace
typically occurs during earthquakes of about magnitude 5 or greater. Surface rupture endangers
life and property when structures or lifeline facilities are located on, or cross over , a fault.
The Los Osos Fault, adjacent to the City of San Luis Obispo, is identified un der the State of
California Alquist-Priolo Fault Hazards Act (Figure18). This fault’s main strand lies near the
intersection of Los Osos Valley Road and Foothill Boule vard. It has been classified as active
within the last 11,000 years. Additional site-specific studies may find other segments of the fault,
in which case it would be appropriate for the California Department of Mines and Geology to
expand the zone. The Los Osos Fault presents a high to very high fault rupture hazard to
development and facilities in the Los Osos Valley.
Other faults in the vicinity of San Luis Obispo are the West Huasna, Oceanic, and Edna faults.
These faults are considered potentially acti ve and present a moderate fault rupture hazard to
developments near them. Figure 19 shows the locations of faults in the immediate San Luis
Obispo area.
Draft Figure 19 Seismic Hazard Designation Area
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Draft Figure 20. Regional Faults
Ground Shaking
Ground shaking refers to the vibration that occurs in response to displacement along a fault.
Typically, ground shaking has a side-to-side component as well as a vertical component, with
the actual movement depending on the type of fault, a site’s distance from the fault, and the rock
and soil conditions at the site. Shaking endangers life a nd property by damaging or destroying
structures and lifeline facilities, including water distribution systems that carry water to the city
from Whale Rock, Nacimiento and Salinas reservoirs. City reservoirs are not located near one
another which reduces the likelihood of damage and loss of all water supplies. Several faults
can produce strong ground motion in San Luis Obispo. These are the Los Osos, Point San Luis,
Black Mountain, Rinconada, Wilmar, Pecho, Hosgri, La Panza, and San Andreas faults (Figure
20). The San Andreas Fault and the offshore Hosgri Fault, which present the most likely source
of ground shaking for San Luis Obispo, have a high probability of producing a ma jor earthquake
within an average lifespan. The highest risk from ground shaking is found on deep soils that
were deposited by water, are geologically recent, and have many pore spaces among the soil
grains. These are typically in valleys.
Engineering standards and building codes set minimum design and construction methods for
structures to resist seismic shaking. Model standards and codes are typically updated every few
years at the recommendation of professional advisors, in response to review of the performance
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of structures and lifelines that have been subject to recent earthquakes. Local governments then
amend or replace their codes to reflect those required by State law or recommended.
Settlement and Liquefaction
In this context, settlement means the ground supporting part of a structure or facility lowers more
than the rest or becomes softer, usually because ground shaking reduces the voids between
soil particles (and often with groundwater rising in the process). The result can be more strain
on the supporting features than they were built to withstand, leading to cracked walls or floors
and broken water and sewer lines. Liquefaction is the sudden loss of the soil’s supporting
strength due to groundwater filling and lubricating the spaces between soil particles as a result
of ground shaking. Soils with high risk for liquefaction are typically sandy and in creek floodplains
or close to lakes. In extreme cases of liquefaction, structures can tilt, break apart, or sink into
the ground. The likelihood of liquefaction increases with the strength and duration of an
earthquake.
The soils in the San Luis Obispo area that are most susceptible to ground shaking, and which
contain shallow ground water, are the ones most likely to have a potential for settlement and for
liquefaction (Figure 21). The actual risk of settlement or liquefaction needs to be identified by
investigation of specific sites, including subsurface sampling, by qualified professionals.
Previous investigations have found that the risk of settlement for new construction can be
reduced to an acceptable level through careful site preparation and proper foundation design,
and that the actual risk of liquefaction is low. (An example is the City’s fire station at Mad onna
Road and Los Osos Valley Road.)
The building code requires site-specific investigations and design proposals by qualified
professionals in areas that are susceptible to settlement and liquefaction.
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Draft Figure 21 Liquefaction Risk Areas
Slope Instability and Landslides
Slope instability can occur as a gradual spreading of soil, a relatively sudden slippage, a rockfall,
or in other forms. Causes include steep slopes, inherently weak soils, saturated soils, and
earthquakes. Improper grading and manmade drainage can be contributing factors. Slope
instability may result in gradual or sudden damage to buildings, roads, and utility lines. Sudden
movement can be a threat to lives through immediate injury or suffocation, or loss of access.
In the late 1990s, rain-saturated soil moved above houses on the Santa Lucia foothills.
Much of the development in San Luis Obispo is in valleys, where there is low potential for slope
instability. However, the city contains extensive hillsides. Several are underlain by th e rocks of
the Franciscan group, which is a source of significant slope instability. The actual risk of slope
instability needs to be identified by investigation of specific sites, including subsurface sampling,
by qualified professionals.
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The building code requires site-specific investigations and design proposals by qualified
professionals in areas that are susceptible to slope instability and landslides.
Damage-Prone Buildings
Any type of building can be damaged in an earthquake, but some types are much more able to
withstand quakes. In the past, many buildings were constructed of clay blocks, bricks, stone, or
concrete blocks, with few or no steel members to resist separation of t he masonry units. The
weight and lack of connectivity within these unreinforced masonry buildings make them a
particular threat to safety in an earthquake. Because many unreinforced masonry buildings have
historic and architectural value, and contain viable businesses, there is reluctance to remove or
replace them quickly. State law has required the City to identi fy unreinforced masonry buildings
and implement a locally devised program to reduce risks. The City has surveyed them and
required owners to evaluate their deficiencies and reinforcing needs. The City requires upgrades
as buildings are remodeled or uses ch ange, and provides fee credits to help offset some of the
cost. A City law required the owners to complete seismic upgrades or demolish the buildings by
2017.
Some non-masonry buildings are especially prone to earthquake damage because they lack
connections to their foundations or resistance to side-to-side motion. Examples include wood-
frame buildings with apartments over garages that have one sid e occupied by a door opening,
and hillside houses with little or no bracing for tall supports on the downhill side. The City
participates in a rehabilitation loan program and a Voluntary Seismic Retrofit Program that
includes standard retrofit plans for free that helps correct such problems, along with other
measures such as bracing masonry chimneys and anchoring water heaters, mainly for older
homes.
Expansive Soils
Expansive soils can change dramatically in volume depending on moisture content . When wet,
these soils can expand; conversely, when dry, they can contract or shrink. Sources of moistures
that can trigger this shrink-swell phenomenon include seasonal rainfall, landscape irrigation,
utility leakage, and/or perched groundwater. Expansive soil ca n develop wide cracks in the dry
season, and changes in soil volume have the potential to damage concrete slab s, foundations,
and pavement. Special building/structure design or soil treatment are often needed in areas with
expansive soils
POLICIES
POLICY GE-6.1: AVOIDING FAULTS
The City shall prohibit development atop known faults. Applications for the following types of
discretionary approvals within 100 meters (330 feet) of any fault that is previously known or
discovered during site evaluation shall be subject to review and recommendation by a State -
registered engineering geologist:
• rezoning to a more intensive land-use designation;
• Tentative Tract Maps;
• Minor, Moderate, and Major Development Review Applications.
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POLICY GE-6.2: AVOIDING SLOPE INSTABILITY
Development shall not be located on or immediately below unstable slopes, or contribute to
slope instability. Any development proposed in an area of moderate or high landslide potential
shall be subject to review and recommendation by a State-registered engineering geologist.
POLICY GE-6.3: AVOIDING LIQUEFACTION HAZARDS
Development shall not be located in areas of high liquefaction potential unless a site-specific
investigation by a qualified professional determines that the proposed development will not be
at risk of damage from liquefaction. The Chief Building Official may waive this requirement upon
determining that previous studies in the immediate area provide sufficient information.
POLICY GE-6.4 STRUCTURAL STABILITY
Require new development to ensure structural stability while not creating or contributing to
erosion, subsidence, or geologic instability or destruction of the site or surrounding area. Ensure
that soils reports are prepared by a licensed civil engineer with expertise in soils and geology.
Prior to acceptance, require soils reports by a certified engineering geologist when developing
in the following areas:
a. Expansive soils and potential for subsidence
b. All areas having cut or fill material on property
c. Where there are known or suspected geologic, soils or hydrologic problems in the
immediate vicinity.
PROGRAMS
PROGRAM GE-6.5: UPDATE THE HILLSIDE PLANNING PROGRAM
Update the City’s Hillside Planning Program to ensure orderly development along the City’s
hillside areas prioritizing slope stability, safe access, circulation, and evacuation routes.
PROGRAM GE-6.6 SAFEGUARD THE INTEGRITY OF UTILITY CONVEYANCE SYSTEMS
INCLUDING WATER PIPELINES FROM CITY RESERVOIRS.
Incorporate climate models and hazard impact assessment in the design and planning of
maintenance and upgrades of water distribution systems from city reservoirs.
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7. City Operations and Emergency Services
OVERVIEW
The City has a comprehensive set plans, policies, and procedures in place to prepare for and
respond to a variety of emergency events. In coordination with San Luis Obispo County, the City
provides emergency services to the community.
EMERGENCY OPERATIONS
City government consists of approximately 457 regular full-time employees and 8 regular part-
time employees and 11 departments at the time of the Climate Adaptation and Safety Element
update. Key departments involved in emergency operations activities include:
• The City of San Luis Obispo Police Department;
• The City of San Luis Obispo Fire Department;
• The City of San Luis Obispo Utilities Department;
• The City of San Luis Obispo Public Works Department;
• The City of San Luis Obispo Parks & Recreation Department; and
• The City Manager’s Office.
The City has many staff with specific training on the use of specialized equipment or areas of
expertise that are essential in implementing mitigation actions. Additionally, the City has several
key planning documents related to emergency operations that help supp ort emergency
operations. These plans and a brief description of their content and purpose are included below.
Emergency Operations Plan– This Plan provides policy and guidance for the coordination of
planning efforts involving the City and related organi zations. The San Luis Obispo Fire
Department is responsible for Disaster Leadership and Preparedness coordination and will
regularly revise and exercise Hazard Specific Annexes and related support materials, as
appropriate. The 2022 Emergency Operations Plan covers the following types of major events:
• Earthquake
• Hazardous Materials Release
• Multiple Casualty Event
• Transportation
• Fire
• Civil Disturbance-Terrorism-Active Shooter
• Diablo Canyon Nuclear Power Plant
• Adverse Weather
• Utility Disruption
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• Pandemic
The Emergency Operations Plan also provides resource materials for staff in the event of an
Emergency Operations Center activation, such as position specific checklists, resource
directory, and specific plans related to debris management, disaster recovery, and Continuation
of Operations and Reconstitution of Government.
City of San Luis Obispo Hazard Mitigation Plan (Annex G in the San Luis Obispo County
Multi-Jurisdictional Plan) – The 2020 San Luis Obispo County Multi-Jurisdictional Hazard
Mitigation Plan was adopted by the City in June 2020. It includes a profile of existing hazards in
the city, assess the probability and severity of each hazard event, and includes a comprehensi ve
set of mitigation actions and implementation strategies while taking into account agency
capabilities to help the City reduce risk from the identified hazards. To remain eligible for many
state and federal funding, grants and assistance programs, the Ci ty must update the Hazard
Mitigation Plan, at a minimum, every 5 years, which is based on the date of FEMA plan approval.
The City also coordinates with many external agencies (e.g., local, state, federal, private sector,
and non-profits) which have capabilities to support hazard mitigation activities. Many of these
agencies participated in the hazard mitigation planning process, including the following:
• County of San Luis Obispo – Airports
• County of San Luis Obispo – Office of Emergency Services
• County of San Luis Obispo – Public Health Department
• Cal Poly – City & Regional Planning Department
• Cal Poly – Administration and Finance
• French Hospital Medical Center
• American Red Cross
• Sierra Vista Regional Medical Center
• San Luis Coastal Unified School District
• California Highway Patrol
• PG&E
• San Luis Obispo County Fire Safe Council
In addition to the plan and policy resources available to the City to mitigate hazards, the City has
developed or participated in several hazard mitigation programs including:
• Unreinforced Masonry Hazard Mitigation Program
• Disaster Preparedness Program
• Floodplain Management Educational Program
• San Luis Obispo Chamber of Commerce Business Continuity Planning
• County Public Health Emergency Preparedness Advisory Committee
• National Flood Insurance Program and FEMA Repetitive Loss Properties
• Community Wildfire Protection Program
• Greenbelt Protection Program
CRITICAL FACILITIES
Critical facilities and infrastructure provide essential services to the public, such as preserving the
quality of life and providing essential public safety, emergency response, and disaster recovery
functions. Different types of critical facilities include medical facilities, evacuation and community
centers, potable water and wastewater facilities, fire stations, and local law enforcement stations.
The County’s HMP organizes critical facilities the following four categories:
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Emergency Services – Facilities or centers aimed at providing for the health and welfare of the
whole population (e.g., hospitals, police, fire stations, emergency operations centers, evacuation
shelters, schools).
Lifeline Utility Systems – Facilities and structures such as potable water treatment plants,
wastewater, oil, natural gas, electric power and communications systems.
Transportation Systems – These include railways, highways, waterways, airways, and city
streets to enable effective movement of services, goods and people.
High Potential Loss Facilities – These include nuclear power plants, dams, and levees.
Transportation infrastructure is discussed in greater detail in Section 3.1, “Assets at Risk” of the
Hazard Mitigation Plan. Table 6 includes the City’s critical facilities and infrastructure are that
have been evaluated for their replacement value and are included in Appen dix G of the Hazard
Mitigation Plan.
Table 6 Critical Facilities and Infrastructure in the City of San Luis Obispo
Category Facility/Infrastructure Asset
Community and Recreational Facilities
City Hall
Library
Ludwick Community Center
Meadow Park Recreational Center
Mitchell Park Senior Center
Sinsheimer Pool and Park
Medical Facilities Sierra Vista Regional Medical Center
French Hospital Medical Center
Schools
California Polytechnic State University
Cuesta College
Laguna Middle School
San Luis Obispo High School
Infrastructure
Critical Bridges
Essential Bridges
Higuera Box Culvert
Evacuation Route Roads
Other Essential City-Owned Roads
Communication Towers
Other City-Owned Facilities
City Corporation Yard
Community Development and Public Works
Administration
Parking Garages
Parks and Recreation Building
Prado Day Center
Utilities Administration
Police and Fire Stations Dispatch Center
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Category Facility/Infrastructure Asset
Fire Station #1
Fire Station #2
Fire Station #3
Fire Station #4
Police Main Building, Garage, Annex
Potable Water and Wastewater
Facilities
Fire Station #4 Well
Pacific Beach Well
Reservoirs
Eight Sewer Lift Stations
Sewer System Infrastructure (pipes) – Approx. 140 miles
Water Resource Recovery Facility
Seven Water Pump Stations
Water System Infrastructure (pipes) – Approx. 180 miles
Eleven Treated Water Storage Tanks
Water Treatment Plant
Note: N/A = not available.
Source: Modified from Table G.9 in San Luis Obispo County 2019b.
RADIATION HAZARDS
The Diablo Canyon Power Plant is the primary hazard for ionizing radiation in the San Luis
Obispo area. Risks result from the potential for mistakes during day-to-day operations, accidents
associated with refueling, and damage from earthquakes or other ca uses. There is added risk
from on-site storage of spent fuel that remains radioactive for several generations. Long -term,
off-site storage facilities for spent fuel are not available. Protective systems are installed, and
emergency plans are in place in the event that any part of the reactor system fails. Diablo Canyon
is scheduled to be decommissioned in 2025 with potential extended operations through 2030
per Senate Bill 846 (SB 846, Dodd). Decommissioning will take approximately ten years after
units are shutdown. The plant operator and local agencies have jointly prepared plans for
warning, sheltering, evacuation, and other responses to radiation emergencies. Updated
information regarding the Emergency Response Plan is distributed to the public each yea r.
Relatively low-level radioactive materials and waste result from some medical facilities and other
sources. The use, transportation, and disposal of these materials are governed by State and
Federal regulations.
Radon is a naturally occurring gas produced by the breakdown of traces of uranium in certain
soils and rocks. This gas can accumulate inside structures where building materials emit or trap
radon, posing a significant health hazard. Soils and rocks in the San Luis Obispo area are not
known to be sources of radon, so it is not considered a substantial local hazard.
HAZARDOUS MATERIALS
Hazardous materials include a wide range of solids, liquids, and gases that are flammable,
explosive, corrosive, or toxic. Because large amounts of hazardous materi als are shipped
through the San Luis Obispo area daily, transportation accidents pose the most significant
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hazardous material risk to residents and the environment. Hazardous materials are transported
along highways, the railroad, and pipelines, which pass through the city.
Public exposure to hazardous materials also can result from their use by industry, agriculture,
and services. In 2022, there were about 195 businesses in the city using hazardous materials in
sufficient quantities to require filing a re port with the Fire Department, as required by the
California Health and Safety Code. Household use of hazardous materials is also a threat to
health and the environment if used or disposed of improperly.
AIRPORT HAZARDS
The San Luis Obispo County Airport provides commuter, charter, and private service to the area.
The primary hazard associated with the airport is the risk of aircraft crashing on approach and
take-off. Aircraft flight operations are determined largely by the physical layout of the airport and
rules of the Federal Aviation Administration. Activities on the airport property are managed by
the County.
Existing land uses under the approach and take-off paths include agriculture and businesses
close to the airport, and shopping centers, dwellings, and schools at greater distances. State
law requires the independent, countywide Airport Land Use Commission to adopt an Airport
Land Use Plan for each airport. This plan establishes zones based on flight patterns, with the
aim of having future development be compatible with airport operations, considering safety and
noise exposure. State and County policies encourage future development to be consistent with
the Airport Land Use Plan.
On May 26, 2021, The County of San Luis Obispo Airport Land Use Commission (ALUC)
adopted the Amended and Restated San Luis Obispo County Regional Airport (SBP) Land Use
Plan (ALUP). In accordance with state law, unless an overrule action is taken, the City’s General
Plan is required to be consistent with the ALUP.
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Draft Figure 22 ALUP Safety Zones
CITY OPERATIONS AND EMERGENCY SERVICES POLICIES
Policy OP-7.1: EMERGENCY PREPAREDNESS AND RESPONSE
Ensure the City and all relevant City departments have adequate planning, organization, and
resources for emergency preparedness and emergency response.
The following response-time programs are intended to apply to recurrent types of emergencies,
not rare, area wide disasters:
A. The Fire Department has set a response-time objective of four minutes. (The Fire
Department’s Master Plan recommends that a three-person engine company, with
paramedic, meet this standard 90 percent of the time).
B. The Police Department has set a one-third (33%) available-time objective for patrol
response. (“Available time” is the fraction of total time that a patrol unit is not previously
assigned or otherwise unavailable for response to a new emergency call for service.) The
presence of available time during a shift allows Officers to perform proactive policing
methods to deter and prevent crime, rather than responding to crime once reported.
Policy OP-7.2: CLIMATE-INFORMED EMERGENCY OPERATIONS PLANNING
The City shall incorporate climate projections and climate impact data into the Emergency
Operation Plan updates.
Policy OP-7.3: EMERGENCY ACCESS AND EVACUATION
Substantial development will be allowed only where multip le routes of road access can be
provided, consistent with other General Plan policies on development location and open space
protection and community risk reduction. “Substantial development” means industrial,
commercial, and institutional uses, multifamily housing, and single-family dwellings in
accordance with adopted fire code. “Multiple routes” include vehicle connections that provide
emergency access only, as well as public and private streets.
Policy OP-7.4: MINIMIZING HAZARDOUS MATERIALS EXPOSURE
The City shall minimize people’s exposure to hazardous substances through ensuring
businesses that use, store, or transport hazardous materials to take adequate measures to
protect public health and safety.
Policy OP-7.5: MITIGATING HAZARDS FROM NEW DEVELOPMENT
New development with sensitive land uses shall be buffered from stationary sources and
mitigated from non-stationary sources of pollution. Development, including access and utility
systems, shall be directed away from hazardous areas as described in the Hazard Mitigation
Plan. Where development, including access and utility systems, cannot avoid hazardous areas,
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the development shall adequately mitigate the hazards and provide that the City and all relevant
City departments have adequate planning, organization, and resources for emergency
preparedness and emergency response. Hazard mitigation measures shall not significantly
impact the environment, including wildlife habitats. Development shall pay an equitable share of
the costs to mitigate area wide hazards. Hazard mitigation measures shall not burden taxpayers
with high maintenance costs. Development shall not increase hazards for other properties in the
area.
Policy OP-7.6: HAZARDOUS MATERIALS IN CITY OPERATIONS
The City shall avoid using hazardous materials in its own operations to the greatest extent
practical, and will follow all established health and safety practices when they are used. When
managing pests and invasive plants, the City should use Integrated Pest Management practices
and avoid the use of chemical insecticides and herbicides to the greatest extent practical.
Policy OP-7.7: BUSINESS AND ECONOMIC RESILIENCE
The City shall incorporate climate projections and climate impact data to develop business and
economic resiliency.
Policy OP-7.8: CLIMATE CHANGE AND FOOD SECURITY
The City shall minimize potential impacts of climate hazards on food security.
CITY OPERATIONS AND EMERGENCY SERVICES PROGRAMS
Program OP-7.9: CLIMATE RESILIENCE FUND
Establish a Climate Resilience Fund to support the implementation of climate adaptation
strategies identified in the Community Safety and Resilience Element. Supplement the Climate
Resilience Fund by identifying and pursuing funding and financing opportunities for specific
climate adaptation and climate-related hazard mitigation strategies. Identify high-priced climate
adaptation strategies or capital improvement projects and research the feasibility of financing
these efforts through green bonds or similar financing mechanisms.
Program OP-7.10: EMERGENCY OPERATIONS CENTER
The City will maintain an Emergency Operations Center Plan, to prescribe the intended
activation and operation of a single facility from which disaster response and essential city
services will be supported. Fire Station 1 will serve as the Emergency Operations Center, with
the Ludwick Center serving as the back-up emergency operations center. The Corporation Yard
and the Police Station serving as department operating centers or tertiary back-up emergency
operation centers if the primary and back -up locations are not viable. The primary Emergency
Operations Center will transfer to the new Public Safety Center located at the existing Police
Headquarters when construction is complete, and occupancy is permitted, at which time, the
Fire Department will become the back-up EOC. The City will maintain back-up power sources
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for the primary and secondary EOC. If a permanent back-up power source is not feasible, the
City will maintain portable back-up power sources.
Program OP-7.11: CLEAN-ENERGY MICROGRID FOR CITY FACILITIES
Continue supporting the City’s current Carbon Neutral City Facilities plan. As part of this plan, if
appropriate, conduct a feasibility study for developing a clean energy microgrid for key City
facilities to provide clean, and reliant back-up power during utility disruptions (e.g., Public Safety
Power Shutoffs or other disruptions) as well as providing local solar power to City facilities for
non-emergency use during the day. Ensure that the feasibility study includes the following details
to allow for the development of a City microgrid, if deemed feasible:
• A review of regulatory and operational considerations
• A conceptual shovel-ready design of the technical components for a fully connected
microgrid and an “islandable” solar + storage system
• A phasing strategy and procurement plan for implementation
• An operational strategy that includes governance and cybersecurity
• Key considerations for operation of the microgrid during short -term and long-utility
disruptions
Seek funding sources including the California Energy Commissions Electric Program Investment
Charge (EPIC) Program and the Pacific Gas and Electric Community Microgrid Enablement
Program (CMEP) to conduct a feasibility study.
Program OP-7.12: CRITICAL FACILITIES LOCATIONS
The following City facilities are necessary for community function and emergency r esponse:
• fire stations
• police main station
• water treatment plant
• raw water storage reservoirs/lakes
• wastewater treatment plant
• public works and utilities corporation yards
• principal telecommunications facilities
New City’s Critical facilities will not be located in 100-year floodplains, in areas of high or extreme
wildland fire hazard, on sites subject to liquefaction or landslide (as distinguished from areas
with potential for these hazards), atop earthquake faults or withing State-designated special
studies zones, or where prohibited by the Amended and Restated San Luis Obispo County
Regional Airport (SBP) Land Use Plan (ALUP). Where the existing city operated critical facilities
are located in these high hazard areas, they shall be flood protected and the city will identify,
and when feasible, implement, mitigation strategies to limit the impacts of associated hazards.
The following facilities operated by entities other than the City, which are necessary for
community function and emergency response, should not be located in 100-year floodplains, in
areas of high or extreme wildland fire hazard, on sites subject to liquefaction or landslide [as
distinguished from areas with potential for these hazards], atop earthquake faults or within State -
designated special studies zones, or where prohibited by the Amended and Restated SBP
ALUP:
• hospitals
• Caltrans and utilities corporation yards
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• principal electrical substations
• principal natural gas transmission mains and pumping stations
• principal public-utility telecommunications and emergency broadcast facilities
• resilience hubs and community centers
Program OP-7.13: WATER SYSTEM RESPONSE PERFORMANCE STANDARDS
The City will evaluate fire-flow capacities and identify deficiencies through testing and modeling
of the water system. For identified deficiencies, the Utilities and Fire Departments will propose
remedies to meet recommended service levels based American Water Works Association
(AWWA) standards and Fire Code regulations.
Program OP-7.14: REDUCING STRUCTURAL HAZARDS
The City will identify and evaluate hazards in existing structures and work toward reducing those
hazards to acceptable levels of risk. The City will advocate that other organizations and agencies
do the same. Highest priority will be given to critical facilities (listed in Program OP-7.12) and
transportation facilities. This overall effort has five basic components:
A. The City’s continuing steps to evaluate, maintain, and replace its own facilities, in
particular bridges, public assembly rooms, fire stations, water tanks, and water and
wastewater treatment plants.
B. Routine inspections for code compliance in commercial, industrial, public-assembly,
group-housing, and multifamily residential buildings.
C. Complaint-based inspections for code compliance in all buildings.
D. Implementation of the City-adopted program to identify and mitigate hazards of
unreinforced masonry buildings.
E. Subject to adequate resources being provided through the budget process, outreach for
private, woodframe buildings involving attachments to adequate foundations, cripple-wall
bracing, water-heater attachment, and bracing or attachment of masonry chimneys.
Program OP-7.15: COORDINATED EMERGENCY PLANNING
The City will work within the Standardized Em ergency Management System, an emergency
response and coordination system used throughout California , the National Incident
Management System, and the National Response Framework. The City will participate in
periodic disaster-response drills, on a regional basis with all involved jurisdictions and involving
the news media.
The City will review the hazard assessment studies and emergency response plans of utilities
and of transportation agencies and companies operating in the San Luis Obispo area, and
update the City’s Emergency Plan, including evacuation routes, as necessary.
The City will work with Caltrans to assure transport of hazardous materials follows Caltrans -
approved routes, with all necessary safety precautions taken to prevent hazardous materials
spills. The City will train fire fighters, police officers, building inspectors, and public works.
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Program OP-7.16: CLIMATE RESILIENCY CHECKLIST FOR NEW DEVELOPMENT
Similar to the City’s GHG Emissions Analysis Compliance Checklist, develop and adopt a
Climate Resiliency Checklist to ensure that new residential and nonresidential development in
the city is designed and built to withstand the forecasted impacts of climate change. Incorporate
all appropriate policies related to new development that are included in the Community Safety
and Resilience Element into the checklist. Items in the Climate Resiliency Checklist should be
objective and comply with all relevant housing laws to eliminate discretionary review. Checklist
items could include:
A. Energy design standards that incorporate future changes in annual average minimum
and maximum temperatures
B. Additional battery storage requirements for certain types of development to mitigate
impacts from future utility disruptions
C. Defensible space and home hardening requirements for development located in high
wildfire risk areas designated by the City
D. Additional building design or site plan requirements to mitigate flood -related impacts in
areas with current or future flood risk
E. Additional building design or landscaping requirement to reduce water consumption in
new development
Program OP-7.17: DEVELOPMENT REVIEW AND INSPECTIONS
The City will maintain and administer its Zoning and Subdivision Regulations and Community
Design Guidelines in conformance with the General Plan. The standards and guidelines will be
consistent with the requirements and recommendations of City police and fire departments.
A. City fire, police, public works, and utilities personnel will review applications for
subdivisions and development projects, for consistency with safety objectives.
B. The City will maintain and administer its building and fire regulations in conformance with
State requirements, including adoption of updated editions of uniform codes.
C. The City will conduct safety inspections for fire and hazardous materials in commercial,
industrial, and multifamily residential buildings.
Program OP-7.18: STAFF TRAINING
The City will train fire fighters, police officers, building inspectors, and public works and utilities
staff to levels appropriate for their tasks and responsibilities. The City will provide training for
those of its staff who apply its building regulations and planning standards, emphasizing th e
lessons learned in locations that have experienced disasters. The City will conduct disas ter-
response exercises for the types of non-nuclear disasters discussed in this element, coordinated
with participation in required, periodic nuclear-disaster response training exercises. All public
employees in the State of California are considered Disaster Service Workers (DSW) and as
such the City will train all employees to ensure basic understanding of DSW responsibilities, the
State Emergency Management System, National Incident Management System and the Incident
Command System.
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PROGRAM OP-7.19: BUILDING CITY CAPACITY FOR CLIMATE RESILIENCE
Identify key gaps in the City’s knowledge of climate adaptation planning and how to integrate
the topic into work efforts. Establish a 1–3 year strategy and workplan to increase City staff
capacity to fully integrate climate change adaptation as a key component of their work for
appropriate departments and staff. Assess progress towards increasing staff capacity to address
climate change on an annual basis and adjust strategy accordingly based on results and new
information and guidance regarding climate adaptation planning. Establish the City’s Green
Team as the official working group to help implement the suite of climate adaptation strategies
included in the Climate Adaptation and Safety Element, identifying representatives from key City
departments to lead climate adaptation efforts in those departments.
PROGRAM OP-7.20: TRADITIONAL ECOLOGICAL KNOWLEDGE
Work with the yak tityu tityu yak tiłhini (Northern Chumash Tribe San Luis Obispo County and
Region (ytt Tribe)), Northern Chumash Tribal Council, and other tribal bodies to incorporate
Traditional Ecological Knowledge approaches into the City’s Open Space Conservation
Guidelines.
PROGRAM OP-7.21: CLIMATE-SMART PEST MANAGEMENT
Integrate Climate-Smart Pest Management Practices into the City’s Open Space Conservation
Guidelines with consideration of how climate change is going to affect pest contro l and invasive
species.
PROGRAM OP-7.22: CLIMATE INFORMED EMERGENCY OPERATION PLAN
During the City’s next comprehensive update of the Emergency Operations Plan (EOP),
incorporate climate projections and climate impact data from the Climate Change Hazards and
Vulnerabilities Report into the plan’s hazard identification and analysis to ensure hazard specific
annexes address climate-related disasters. Analyze future staffing and resource requirements
to adequately address the future frequency and intensity of climate -related hazards in the city.
Develop protocols for novel climate -related hazards that the city has previously experienced
which are not adequately addressed in existing EOP hazard-specific annexes.
PROGRAM OP-7.23: CLIMATE INFORMED ECONOMIC DEVELOPMENT STRATEGIC PLAN
Work with the local business community to identify key economic sectors that are vulnerable to
impacts from climate-related hazards and other hazards identified in the Hazard Mitigation Plan
(e.g., tourism) and develop a strategy to diversify the City’s economy to avoid overreliance on
economic sectors that are vulnerable to climate impacts and local hazards. Work with the San
Luis Obispo Chamber of Commerce to identify bu sinesses and local industries already being
affected by climate-related impacts (e.g., drought, wildfire smoke, extreme heat, flood) and
identify opportunities to help support affected industries. Where economic vulnerabilities pose a
risk to ongoing City revenues, develop programs to bolster the City’s financial resilience through
a Resilience Fund or other measures.
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PROGRAM OP-7.24: FOOD SECURITY
Work with community organizations (e.g., SLO Food Bank) and the SLO County Health
Department to assess potential impacts of climate hazards on food availability, food prices and
food insecurity in the city, particularly for disadvantaged communities. Partner with community
organizations to address food insecurity including opportunities to support food recovery efforts
as part of implementation of Senate Bill 1383 to reduce food waste and associated greenhouse
gas emissions.
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Implementation
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OVERVIEW
This section provides information on how the City can successfully implement the set of policies
and programs included in the Climate Adaptation and Safety Element. It describes how best to
conduct ongoing community engagement during implementation as well as develop key regional
and community partnerships to ensure successful implementation of the policies and programs.
The section also identifies appropriate funding and financing sources to support implementation.
Finally, the section provides a succinct timeline to help the City prioritize implementation of the
policies and programs.
COMMUNITY ENGAGEMENT AND PARTNERSHIPS
Effective implementation of the policies and programs in the Climate Adaptation and Safety
Element will require sustained collaboration with community partners and regional agencies, as
well as collaboration among City departments. Collaboration with partners during the strategy
implementation process ensures that knowledge and resources will be shared and allows the City
to implement strategies effectively. Many of the strategies that focus on hazard preparedness
involve helping residents prepare their household and neighborhoods for climate-related hazards
(e.g., flooding, heat wave events). By conducting community outreach and involving residents in
the implementation process, the City will ensure that the community overall will be better prepared
to respond to and adapt to changing circumstances, whether they are chronic stresses, such as
climate change, or acute shocks, such as an earthquake. Community engagement during
implementation can also help create a committed group of community stakeholders who will help
implement strategies and help create sustained commitment in the community for achieving
successful implementation (Cal OES 2020). The City will utilize a whole Community approach
which will attempt to engage the full capacity of the private and nonprofit sectors, including
businesses, faith-based and disability organizations, and the general public, in conjunction with
the participation of local, tribal, state, territorial, and Federal governmental partners. This Whole
Community approach is a means by which residents, City officials, organizational and
community leaders can collectively understand and assess the needs of their re spective
communities and determine the best ways to organize and strengthen their assets, capacities,
and interests (FEMA 2011).
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COMMUNITY RESILIENCE ROUNDTABLE
As part of implementation, the City will establish a Community Resilience Roundtable
(Roundtable) to help increase the City’s capacity and knowledge base for implementing the
comprehensive policies and programs in this element. Successful implementation will require
the expertise and experience of various parts of the community and the larger San Lu is Obispo
region (e.g., the transportation system, the flood management system, and community
preparedness). The Roundtable will be comprised of technical experts, residents,
representatives from community organizations, members of the business community, City staff,
and other relevant partners. The primary responsibilities of the Roundtable will be to (1) meet
regularly to guide the successful implementation of the Climate Adaptation and Safety Element,
(2) assist the City by providing subject area expertise as various policies and program are
implemented, (3) help increase the City’s capacity to implement strategies by encouraging
collaboration with regional and State agencies and community partners, and (4) review and
support grant applications for identified actions as appropriate to leverage additional fun ds for
implementation.
SUSTAINED COMMUNITY ENGAGEMENT
The City will need to host community outreach events to gather input on how best to implement
the strategy and identify community priorities to help design strategy implementation. Many of the
programs in the element will require sustained community participation or comprehensive
infrastructure updates, requiring significant City staff time and resources. By conducting sustained
community outreach during implementation, the City can gain support and buy-in from members
of the community who will help advocate for and support implementation of these strategies.
The City is developing an interactive website that will provide a platform for easy access for
residents and serve as a real-time tool to monitor and provide input on implementation of specific
strategies. The website will also serve as a platform for community members to receive the most
up-to-date information on ways to get involved in implementation of certain strategies, attend
community events, and participate in other activities to support implementation. The website will
be updated regularly to report progress on implementation of individual strategies.
IMPLEMENTATION WORKPLAN
The tables included in this section provides a ten -year timeline for when programs related to
each hazard in the element should be implemented by the City. The implementation timelines
have been designed to account for overlaps in similar programs to maximize the City’s capacity
and resources for implementation as well as for the time required for the strategy to be fully
implemented and become effective in mitigating various hazard.
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Climate Adaptation and Safety Element | 85
PROGRAM IMPLEMENTATION TIMELINE
Program Program Name Lead Department Immediate Near Term
(2023-27)
Long term
(by 2035) Ongoing
High Impact Multi Hazard Resilience Solutions
MH-1.5 Update the City’s Capital Improvement Program to Incorporate Climate
Projections
Public Works x
MH-1.6 Update City’s Engineering Standards and Specifications to Incorporate
Climate Projections
CDD x
MH-1.7 Climate Smart Natural Resource Management Office of Sustainability
and Natural
Resources
x
MH-1.8 Climate Resilience Hubs Office of Sustainability
and Natural
Resources
x
MH-1.9 Post-Disaster Recovery Debris Management Utilities x
MH-1.10 Post-Disaster Recovery Resources and Education CDD x
MH-1.11 Regional Collaboration and Community Resilience Ambassadors Office of Sustainability
and Natural
Resources
x
Environmental Justice
EJ-2.3 Empower Community Organizations Office of Sustainability
and Natural
Resources
x
EJ-2.4 Ensure Public Engagement Noticing Manual Advances Procedural Equity Office of Diversity,
Equity, and Inclusion
x
EJ-2.5 Develop Equity Checklist for City Programs and Capital Improvement
Projects
Public Works x
EJ-2.6 Establish Community Resilience Fund Administration
EJ-2.7 Report on Equity and Environmental Justice Progress Administration x
Flooding
FL-3.7 Waterway Management Plan Office of Sustainability
and Natural
Resources
x
FL-3.8 Flood Damage Prevention Office of Sustainability
and Natural
Resources
x
FL-3.9 Sustainable Flood Management and Open Space CDD x
FL-3.10 Urban Creeks Vegetation Management Plan Office of Sustainability
and Natural
Resources
x
FL-3.11 Flood-Prepared Neighborhoods Program Fire Department x
FL-3.12 Community-Driven Flood Education Administration x
FL-3.13 Flood Warning Monitoring System CDD x
Extreme Heat
HE-4.4 Urban Heat Island Mitigation Program CDD x
HE-4.5 Climate-Smart Urban Tree Canopy Public Works x
HE-4.6 Community Cool Zones Network CDD x
HE-4.7 Green and Healthy Buildings Program Office of Sustainability
and Natural
Resources
x
HE-4.8 Extreme Heat and Emergency Preparedness Fire Department x
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Climate Adaptation and Safety Element | 86
Program Program Name Lead Department Immediate Near Term
(2023-27)
Long term
(by 2035) Ongoing
High Impact Multi Hazard Resilience Solutions
HE-4.9 Equitable Community Outreach for Extreme Heat CDD x
Fire
FI-5.12 Implement the Community Wildfire Protection Plan Fire Department x
FI-5.13 Implement the Vegetation Management Plan Office of Sustainability
and Natural
Resources
x
FI-5.14 Wildfire Ignition Source Reduction Program Fire Department x
FI-5.15 Wildland-Urban-Interface Defensible Space and Home Hardening Program Fire Department x
FI-5.16 Resident Information and Training on Fire Hazards Fire Department x
FI-5.17 Wildfire Smoke Protection Outreach Strategy Fire Department x
FI-5.18 Support Community Resilience During Public Safety Power Shutoffs
CDD x
Earthquakes and other Geologic Hazards
GE-6.5 Update the Hillside Planning Program CDD x
GE-6.6 Inspect and Safeguard the Integrity of Utility Conveyance Systems
Including Water Pipelines from City Reservoirs
Utilities x
City Operations and Emergency Services
OP-7.9 Climate Resilience Fund CDD x
OP-7.10 Emergency Operations Center Fire & Police
Departments
x
OP-7.11 Clean-Energy Microgrid for City Facilities Public Works x
OP-7.12 Critical Facilities Locations CDD x
OP-7.13 Water System Response Performance Standards Utilities & Fire
Departments
x
OP-7.14 Reducing Structural Hazards CDD x
OP-7.15 Coordinated Emergency Planning Fire & Police
Departments
x
OP-7.16 Climate Resiliency Checklist for New Development CDD x
OP-7.17 Development Review and Inspections CDD x
OP-7.18 Staff Training Administration x
OP-7.19 Building City Capacity for Climate Resilience Administration x
OP-7.20 Traditional Ecological Knowledge Office of Sustainability
and Natural
Resources
x
OP-7.21 Climate-Smart Pest Management Office of Sustainability
and Natural
Resources
x
OP-7.22 Climate-informed Emergency Operations Plan Fire & Police x
OP-7.23 Climate-informed Economic Development Strategic Plan Economic Dev. x
OP-7.24 Food Security Administration & DEI x
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Implementation
Climate Adaptation and Safety Element | 87
FUNDING AND FINANCING
Successful implementation of the resilience strategies will require both City staff time and
resources. In many cases, it also will require funding for consultants to assist with
implementation, as well as m aterial costs to complete physical upgrades to th e city’s
infrastructure and the built environment. For other strategies, the City will be able to integrate
strategies into existing operations and procedures, as well as into already planned projects. The
funding required to implement the strategies will need to come from a variety of sources,
including both external funding opportunities, such as grants, and the internal funding sources
devoted to climate resilience, such as general fund revenue sources. Th e following discussion
identifies available external funding opportunities and presents a summary of internal funding
mechanisms that the City can use to implement the strategies.
EXTERNAL FUNDING OPPORTUNITIES
Federal, State, and local grants can help fill the gap for projects that cannot be funded from the
City’s general fund or local funding mechanisms.
Federal Emergency Management Agency: Hazard Mitigation Assistance Grants
FEMA’s hazard mitigation assistance grants provide funding for eligible mitigation measures that
reduce disaster losses. FEMA administers four hazard mitigation assistance grant programs
relevant to the City:
Hazard Mitigation Grant Program—Assists in implementing long-term hazard mitigation
planning and projects following a Presidential major disaster declaration
Flood Mitigation Assistance Program—Provides funds for planning and projects to
reduce or eliminate the risk of flood damage to buildings that are insured annually under
the National Flood Insurance Program
Building Resilient Infrastructure & Communities—Support for states, local
communities, tribes, and territories as they undertake hazard mitigation projects, reducing
the risks they face from disasters and natural hazards
Pre-Disaster Mitigation Program—Provides funds annually for hazard mitigation
planning and projects
National Oceanic and Atmospheric Administration: Environmental Literacy Grants
The goal of this funding opportunity is to improve the environmental literacy of K –12 students
and the public so that they are knowledgeable of the ways in which their community can become
more resilient to extreme weather and other environmental hazards and become involved in
achieving that resilience. Projects are intended to build the collective environmental literacy
necessary for communities to become more resilient to the extreme weather and other
environmental hazards they face in the short and long term.
U.S. Department of Agriculture: Conservation Innovation Grants
The Conservation Innovation Grant program is a voluntary program intended to stimulate the
development and adoption of innovative conservation approaches and technologies while
leveraging federal investment in environmental enhancement and protection, in conjunction with
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Climate Adaptation and Safety Element | 88
agricultural production. These projects ma y be watershed-based, regional, or statewide in
scope.
CivicSpark Program
The CivicSpark Program supports sustainability-focused research, planning, and
implementation projects throughout California by providing public agencies and other
organizations with capacity-building support to implement sustainability projects or programs
from CivicSpark Fellows. Fellows serve for 11 months and can work on variety of issues
including social equity, climate resilience, water resource management, affordable housing, and
mobility.
California Climate Investments
California Climate Investments is a statewide initiative that directs funds from the State’s Cap -
and-Trade Program to projects and programs that work to reduce greenhouse gas emissions in
the state. These funds can support a variety of projects, including affordable housing, renewable
energy, public transportation, environmental restoration, more sustainable agriculture, and
recycling. Numerous State programs, including some discussed above, are funded through
California Climate Investments; however, the State’s Cap-and-Trade Program continues to
evolve and is updated by the State periodically to include new or modified programs.
LOCAL FUNDING AND FINANCING MECHANISMS
Considering that major updates to the City’s built environment (e.g., flood management system)
may be needed to help prepare for current or future climate-relate hazards, financing
mechanisms may need to be leveraged to pay for projects with large upfront costs. Financing
requires a source of repayment, commonly referred to as funding, to secure a large upfront
payment that is then paid back over time with interest.
In California, laws and regulations that govern how revenue can be raised from taxes,
assessments, and fees, combined with the need for a variety of public investments competing
for the same dollars, can make securing funding a larger challenge than securing financing.
Making a compelling case that ensures broad -based public support by clearly articulating the
cost of inaction (e.g., what will be lost without the investment in the context of progressive climate
impacts) and the resulting co-benefits is an important component of securing funding for climate-
related investments through mechanisms such as taxes, assessments, and fees, as well as
successfully pursuing grants and other external funding opportunities.
After funding is secured, typical financing mechanisms used by local governments include
municipal bonds and loans, although in recent years, additional types of bonds that include
consideration of characteristics that may be relevant for climate-related investments, such as
green bonds, are now offered. Selection of a financing mechanism should be based on the total
cost of the financing and its suitability for funding the needed inve stment.
The mechanisms discussed below are a few of those commonly used to implement climate
adaptation projects, which may have multiple sources of funding and/or financing. An
assessment of which mechanisms would be used to pay for resilience strategies would be
conducted as the City begins to implement the policies and programs.
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Climate Adaptation and Safety Element | 89
Funding
Taxes: The cost of large infrastructure projects can be offset through various tax mechanisms.
For adaptation and resilience projects, a tax is generally a special tax t hat is implemented to pay
for a specific project or program. Because of voter approval requirements, special taxes can be
more difficult to develop without a clear understanding by the public of their purpose and the
specific benefits they provide. Under California law, if a jurisdiction would like to adopt, increase,
or extend a special tax, a two-thirds-majority approval is required. General taxes can pass with
a simple majority. The following common types of taxes could be used to fund appropriate
resilience strategies:
• Ad valorem property tax—This is a tax levied on property owners based on a property’s value.
It can be used only to finance voter-approved debt or finance bonds for infrastructure
projects. The requirements for voter approval to raise prop erty taxes depend on the type of
infrastructure project being funded. In general, property tax increases for infrastructure bonds
need approval by two-thirds of local voters.
• Parcel taxes—This is a form of property tax assessed based on certain established
characteristics of a parcel rather than a rate based on the assessed value of the property. A
parcel tax is considered a special tax and requires approval from two -thirds of all local voters.
• Mello-Roos taxes—A Mello-Roos district is a special district established by a local
government to obtain additional public funding for specific projects or services, such as
emergency services (e.g., fire departments, police) or public work projects (e.g.,
infrastructure improvements).
Financing
Bonds: A bond is a financing tool whereby money borrowed from investors is paid back with
interest. Bonds are bought and sold on the bond market. Local governments can finance specific
resilience projects by issuing bonds.
Green Bonds: For adaptation and resilience projects, green bonds can expand the potential
investor pool by characterizing aspects of the investment that interest investors focusing on
projects with defined environmental performance characteristics, but this approach could have
higher administrative costs. Several green and climate bond certifications, such as the Climate
Bond Standard and the Green Bond Principles, have been created to standardize the definition
of the environmental characteristics of green bond projects.
Loans
Loans are a financing tool whereby a party borrows money from a single source, such as a bank
or the government, for a specific purpose. Loans can have fixed interest rates, as bonds do, but
they often have variable interest rates, making them less attractive to cities that have budge ts
that fluctuate over time. Loan payback terms also tend to be shorter than bond payback terms.
Commercial loans are available to local governments for resilience - and infrastructure-related
projects in California from the Infrastructure State Revolving F und, which provides financing to
nonprofits and public agencies for infrastructure and economic development (excluding
housing).
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Climate Adaptation and Safety Element | 90
°C degrees Celsius
°F degrees Fahrenheit
AB Assembly Bill
AR atmospheric river
CAL FIRE California Department of Forestry and Fire Protection
Cal Poly California Polytechnic State University at San Luis Obispo
CIP Capital Improvement Projects
City City of San Luis Obispo
County San Luis Obispo County
CWPP Community Wildfire Protection Plan
EOP Emergency Operations Plan
EMF electromagnetic field
FEMA Federal Emergency Management Agency
GHG greenhouse gas
HMP Hazard Mitigation Plan
LHMP Local Hazard Mitigation Plan
PG&E Pacific Gas and Electric
SB Senate Bill
SLOCOG San Luis Obispo Council of Governments
TAZ traffic analysis zone
U.S. 101 U.S. Highway 101
UHI urban heat island
VHFHSZ Very High Fire Hazard Severity Zones
WMP Waterway Management Plan
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Climate Adaptation and Safety Element | 91
100-Year Flood: A flood that has a 1 percent likelihood of occurring in any given year.
100-Year Floodplain: The areas that have a 1-in-100 chance of flooding in any given year using
criteria consistent with, or development by, the Federal Emergency Management Agency.
200-Year Floodplain: The areas that have a 1-in-200 chance of flooding in any given year using
criteria consistent with, or development by, the Department of Water Resources.
500-Year Floodplain: The areas that have a 1-in-100 chance of flooding in any given year using
criteria consistent with, or development by, the Department of Water Resources.
Adaptive Capacity: The ability of systems, institutions, humans, and other organisms to adjust
to potential damage, to take advantage of opportunities, or to respond to consequences (IPCC
2014).
Alquist-Priolo Earthquake Fault Zone: A regulatory zone, delineated by the State Geologist,
within which site-specific geologic studies are required to identify and avoid fault rupture hazards
prior to subdivision of land and/or construction of most structures for human occupancy.
Climate Adaptation: Adjustment or preparation of natural or human systems to a new or
changing environment that moderates harm or exploits beneficial opportunities.
Climate Mitigation (Greenhouse Gas Emissions Reductions): A human intervention to
reduce the human impact on the climate system; it includes strategies to reduce greenhouse
gas sources and emissions and enhancing greenhouse gas sinks. Refer to Chapter 7, Climate
Change, for more information.
Critical Facility: Facilities that either (1) provide emergency services or (2) house or serve many
people who would be injured or killed in case of disaster damage to the facility. Examples include
hospitals, fire stations, police and emergency services facilities, utility facilities, and
communications facilities.
Extreme Weather Event: In most cases, extreme weather events are defined as lying in the
outermost (“most unusual”) ten percent of a place’s history. Analyses are available at the national
and regional levels.
Fault: A fracture or zone of closely associated fractures along which rocks on one side have
been displaced with respect to those on the other side. A fault zon e is a zone of related faults
which commonly are braided, but which may be branching. A fault trace is the line formed by the
intersection of a fault and the earth’s surface.
Active Fault: A fault that has exhibited surface displacement within Holocene time
(approximately the past 11,000 years).
Potentially Active Fault: A fault that shows evidence of surface displacement during
Quaternary time (the last 2 million years).
Flooding: A rise in the level of a water body or the rapid accumulation of runoff, including related
mudslides and land subsidence, that results in the temporary inundation of land that is usually
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Climate Adaptation and Safety Element | 92
dry. Riverine flooding, coastal flooding, mud flows, lake flooding, alluvial fan flooding, flash
flooding, levee failures, tsunamis, and fluvial stream flooding are among the many forms that
flooding takes.
Hazardous Material: An injurious substance, including pesticides, herbicides, toxic metals and
chemicals, liquefied natural gas, explosives, volatile chemicals, and nuclear fuels.
Hazard Mitigation: Sustained action taken to reduce or eliminate long-term risk to people and
their property from hazards and their effects.
Landslide: A general term for a falling, sliding, or flowing mass of soil, rocks, water, and debris.
Includes mudslides, debris flows, and debris torrents.
Liquefaction: A process by which water-saturated granular soils transform from a solid to a
liquid state during strong ground shaking.
Resilience: The ability of a social or ecological system to absorb disturbances while re taining
the same basic structure and ways of functioning, the capacity for self -organization, and the
capacity to adapt to stress and change.
Seiche: An earthquake-induced wave in a lake, reservoir, or harbor.
Subsidence: The gradual, local settling or sinking of the earth’s surface with little or no
horizontal motion (subsidence is usually the result of gas, oil, or water extraction,
hydrocompaction, or peat oxidation, and not the result of a landslide or slope failure).
Social cohesion: The extent of connectedness and solidarity among groups in society or
community. Social cohesion is one of the strongest indicators of resilience during disaster events
as well as in post-disaster recovery efforts (Townshend et al. 2015). S ocial cohesion can play
an important role in helping protect residents, particularly vulnerable populations, during climate -
related disasters. While measuring the degree of social cohesion present in the City is not
possible at this point, this subject is discussed here to emphasize the importance of social
cohesion in increasing community resilience to the impacts of the climate change.
Tsunami: A wave, commonly called a tidal wave, caused by an underwater seismic disturbance,
such as sudden faulting, landslide, or volcanic activity. Wildland Fire: A fire occurring in a
suburban or rural area that contains uncultivated lands, timber, range, watershed, brush, or
grasslands. This includes areas where there is a mingling of developed and undeveloped lands.
Page 233 of 669
Climate Adaptation and Safety Element | 93
American Planning Association. 2017 (May). APA Blog: Planning for Resilience. Available:
https://www.planning.org/blog/blogpost/9124762/. Accessed August 24, 2020.
APA. See American Planning Association.
Borgschulte, M, Molitor, D, and Zou, E, Y. 2019. Air Pollution and the Labor Market: Evidence
from Wildfire Smoke. Institute of Labor Economics 2019 Annual Conference.
California Department of Forestry and Fire Protection. 2020. Fire and Resource Assessment
Program Fire Perimeter Data. Available: http://frap.fire.ca.gov/data/frapgisdata-subset.
Accessed August 24, 2020.
California Energy Commission. 2019a. Cal-Adapt Annual Averages Tool.
———. 2019a. Cal-Adapt Annual Averages Tool.
———. 2019B. Wildfire Tool.
California Environmental Justice Alliance. 2017. SB 1000 Implementation Toolkit: Planning for
Healthy Communities
California Natural Resources Agency. 2018 (January). Safeguarding California Plan: California’s
Climate Adaptation Strategy. 2018 Update.
California Governor’s Office of Planning and Research, 2017, General Plan Guidelines.
California Governor’s Office of Planning and Research, 2020, General Plan Guidelines Chapter
4: Environmental Justice Element.
OEHHA 2018
Cal OES 2020
Cal Poly 2020
cbec eco engineering 2021
CEC 2019d
Chen, L. 2020. Impacts of climate change on wind resources over North America based on NA-
CORDEX. Renewable Energy, 153, 1428-1438.
Page 234 of 669
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Climate Adaptation and Safety Element | 94
Centers for Disease Control and Prevention. 2019. Protecting Vulnerable Groups from Extreme
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———. 2014 (December 9). Chapter 5, Safety. In City of San Luis Obispo General Plan. Adopted
July 5, 2000. Last revised December 9, 2014. Available:
https://www.slocity.org/home/showdocument?id=6645. Accessed August 24, 2020.
City of San Luis Obispo 2019
City of San Luis Obispo 2021
CDC n.d.
EPA. See U.S. Environmental Protection Agency.
FEMA 1978
FEMA 2011 referenced from FEMA's "A Whole Community Approach to Emergency
Management: Principles, Themes, and Pathways for Action"
https://www.fema.gov/sites/default/files/2020-07/whole_community_dec2011__2.pdf
George S. Nolte & Associates. 1977. Flood Control and Drainage Master Plan for the San Luis
Obispo Creek Watershed.
Governor’s Office of Planning and Research, California Energy Commission, and California
Natural Resources Agency. 2018a. California’s Fourth Climate Change Assessment.
———. 2018b. California’s Fourth Climate Change Assessment: Central Coast Region Report.
Intergovernmental Panel on Climate Change. 2014. Climate Change 2014 Synthesis Report:
Approved Summary for Policymakers.
———. 2018. Special Report: Global Warming of 1.5 °C
Jenson, J. 1998. Mapping social cohesion: the state of Canadian research. Canadian Policy
Research Networks Study No. F-03.
The Nature Conservancy 2014
NOAA 2021
OEHHA. See California Office of Environmental Health Hazard Assessment.
Questa Engineering Corporation. 2003. Waterway Management Plan. Prepared for the City of
San Luis Obispo Department of Public Works and the County of San Luis Obispo Flood
Control District – Zone 9.
Ramin, B., and Svoboda, T. 2009. Health of the homeless and climate change. Journal of Urban
Health, 86(4), 654-664.
Rappold, A. G., J. Reyes, G. Pouliot, W. E. Cascio, and D. Diaz-Sanchez. 2017. Community
Vulnerability to Health Impacts of Wildland Fire Smoke Exposure. Environmental Science
and Technology.
Rodin, Judith. 2014. The Resilience Dividend: Managing Disruption, Avoiding Disaster, and
Growing Stronger in an Unpredictable World.
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San Luis Obispo County. 2019 (October). Annex G: City of San Luis Obispo Community Profile.
Available: https://www.slocounty.ca.gov/getattachment/f97614f4 -39a1-4819-810e-
4d7b637a5507/San-Luis-Obispo-County-Annexes-Municipalities-A-G.aspx. Accessed
August 24, 2020.
———. 2016 was a bad year for valley fever in SLO County. 2017 is looking even worse.
San Luis Obispo County 2019a (ch.8)
San Luis Obispo County 2019b
Sailor, D. J. 2011. A Review of Methods for Estimating Anthropogenic Heat and Moisture
Emissions in the Urban Environment. International Journal of Climatology 31:189–199.
Schwartz, M. W., N. Butt, C. R. Dolanc, A. Holguin, M. A. Moritz, M. P. North, H. D. Safford, N.
L. Stephenson, J. H. Thorne, and P. J. van Mantgem. 2015. Increasing elevation of fire
in the Sierra Nevada and implications for forest change.
Swain, D. L., D. E. Horton, D. Singh, and N. S. Diffenbaugh. 2016. Trends in Atmospheric
Patterns Conducive to Seasonal Precipitation and Temperature Extremes in California.
Science Advances 2(4): e1501344.
Swain, D. L., B. Langenbrunner, J. D. Neelin, and A. Hall. 2018. Increasing Precipitation Volatility
in Twenty-First-Century California. Nature Climate Change 8:427–433.
Townshend, I., Awosoga, O., Kulig, J., and Fan, H. 2015. Social cohesion and resilience across
communities that have experienced a disaster. Natural Hazards, 76(2), 913-938.
USACE. See U.S. Army Corps of Engineers.
U.S. Army Corps of Engineers, L.A. District. 1974. Floodplain Information: San Luis Obispo
Creek and Tributaries Vicinity of San Luis Obispo, San Luis Obispo County, California.
U.S. Environmental Protection Agency. 2008. Reducing Urban Heat Islands: Compendium of
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Voelkel, J., D. Hellman, R. Sakuma, and V. Shandas. 2018. Assessing Vulnerability to Urban
Heat: A Study of Disproportionate Heat Exposure and Access to Refuge by Socio-
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Westerling, A. L. 2018. Wildfire Simulations for the Fourth California Climate Assessme nt:
Projecting Changes in Extreme Wildfire Events with a Warming Climate. University of
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Zhu and Zhang 2008
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DECEMBER 2021
Climate Change Hazards
and Vulnerabilities Report
City of San Luis Obispo
990 Palm Street
San Luis Obispo, CA 93401 DRAFTPage 237 of 669
DRAFTPage 238 of 669
20200048.01
Resilient SLO: Climate Change Hazards and
Vulnerabilities Report
Prepared for:
City of San Luis Obispo
990 Palm Street
San Luis Obispo, CA 93401
Prepared by:
Ascent Environmental
455 Capitol Mall, Suite 300
Sacramento, CA 95814
Authors
Ascent: Angie Xiong, Kai Lord-Farmer,
and Honey Walters
Fehr & Peers: Marshall Ballard,
Charlie Coles, and Taylor Whitaker
cbec: Chris Bowles, Luke Tillmann,
and Michael Founds
December 2021 DRAFTPage 239 of 669
DRAFTPage 240 of 669
City of San Luis Obispo i
Climate Change Hazards and Vulnerability Report
TABLE OF CONTENTS
Section Page
LIST OF ABBREVIATIONS ......................................................................................................................................................................... IV
1 INTRODUCTION ........................................................................................................................................................................ 1-1
1.1 Climate Change Overview .............................................................................................................................................. 1-2
1.2 What is Resilience? ............................................................................................................................................................ 1-3
2 CLIMATE HAZARDS ASSESSMENT .......................................................................................................................................2-1
2.1 Vulnerability Assessment Methodology .................................................................................................................... 2-1
2.2 Social Vulnerability and Environmental Justice ...................................................................................................... 2-7
2.3 Temperature and Extreme Heat Analysis ............................................................................................................... 2-18
2.4 Long-Term Drought Analysis ..................................................................................................................................... 2-38
2.5 Wildfire Analysis .............................................................................................................................................................. 2-46
2.6 Precipitation and Flooding Analysis ......................................................................................................................... 2-69
3 VULNERABILITY SCORING SUMMARY ................................................................................................................................3-1
4 REFERENCES .............................................................................................................................................................................. 4-1
Appendices
Appendix A –
Figures
Figure 1 California Adaptation Planning Guide Adaptation Planning Phases ................................................................1-1
Figure 2 California Adaptation Planning Guide Vulnerability Assessment Process .................................................... 2-2
Figure 3 Representative Concentration Pathwa y Used in Global Climate Modeling ................................................. 2-4
Figure 4 Low-Income Communities as Defined under Assembly Bill 1550 ................................................................... 2-9
Figure 5 Regionally-Defined Disadvantaged Communities in the City of San Luis Obispo .................................. 2-12
Figure 6 Census Tracts in the City of San Luis Obispo ....................................................................................................... 2-13
Figure 7 Location and Relative Density of Homeless Encampments in the City of San Luis Obispo ..................2-17
Figure 8 City Resident’s Climate Concern by Age ................................................................................................................ 2-18
Figure 9 Climate -Related Hazard Impacts on Community Organizations in the City of San Luis
Obispo ................................................................................................................................................................................ 2-19
Figure 10 Average Annual Maximum and Minimum Temperatures in the City (1926 -2018) ................................... 2-20
Figure 11 Changes in Annual Average Temperature in San Luis Obispo County through 2099 ........................... 2-21
Figure 12 Urban Heat Island Effect and Tree Cover in the City ......................................................................................... 2-26
Figure 13 Youth and Elderly Populations and Urban Heat Island Severity in the City ............................................... 2-29
Figure 14 Asthma Rate Prevalence and Urban Heat Island Severity in the City .......................................................... 2-30
Figure 15 Low-Income Areas and Urban Heat Island Severity in th e City ..................................................................... 2-33
Figure 16 Relative Changes in Extreme Heat by 2050 .......................................................................................................... 2-34
Figure 17 City Resident’s Extreme Heat Concern and Impact ............................................................................................ 2-35 DRAFTPage 241 of 669
Table of Contents Ascent Environmental
City of San Luis Obispo
ii Climate Change Hazards and Vulnerability Report
Figure 18 Projected Drought Conditions between 2051 and 2070 for San Luis Obispo County ........................... 2-39
Figure 19 Wildfire Hazard Severity Zones In and Near the City of San Luis Obispo with Cr itical Facilities ........ 2-47
Figure 20 Change in Average Annual Maximum Temperature in San Luis Obispo County through 2099 ........ 2-48
Figure 21 Biophysical and anthropogenic d eterminants of wildfire ................................................................................. 2-51
Figure 22 Changes in the WUI areas within the City 2001-2016 ........................................................................................ 2-53
Figure 23 Wildfire Hazard Severity Zones and Percent of No Vehicle Household per Block Group .................... 2-56
Figure 24 Share of Older Adults and Youth and Fire Hazard Severity Zone in the City ........................................... 2-58
Figure 25 SLOCOG Identified Disadvantaged Communities and Fire Hazard Severity Zone in the City ............ 2-59
Figure 26 Low-Income Populations and Fire Hazard Severity Zone in the City ........................................................... 2-60
Figure 27 Homeless Encampments and Fire Hazard Severity Zone in the City ........................................................... 2-61
Figure 28 Potential PG&E PSPS Events per Year by Month ................................................................................................ 2-62
Figure 29 California Public Utility Commission Fire Threat Map ....................................................................................... 2-63
Figure 30 City Resident’s Wildfire and Wildfire Smoke Concern and Impact ............................................................... 2-65
Figure 31 HEC-RAS Hydraulic Model Extent............................................................................................................................. 2-73
Figure 32 Flood Depth: Full Extent - Q100 (Historic) ............................................................................................................. 2-76
Figure 33 Flood Depth: SLO-Stenner - Q10 (Historic) Flood Depth - Q100 (Historic) ................................................ 2-77
Figure 34 Flood Depth: SLO-Stenner - Q10 (Future 2070-2099 – RCP 8.5) ................................................................... 2-78
Figure 35 Flood Depth: SLO-Stenner - Q100 (Historic) ......................................................................................................... 2-79
Figure 36 Flood Depth: SLO-Stenner - Q100 (Future 2070-2099 – RCP 8.5) ................................................................ 2-80
Figure 37 Flood Depth: SLO-Prefumo - Q10 (Historic) ......................................................................................................... 2-81
Figure 38 Flood Depth: SLO-Prefumo - Q10 (Future 2070-2099 – RCP 8.5) ................................................................. 2-82
Figure 39 Flood Depth: SLO-Prefumo - Q100 (Historic) ....................................................................................................... 2-83
Figure 40 Flood Depth: SLO-Prefumo - Q100 (Future 2070-2099 – RCP 8.5)............................................................... 2-84
Figure 41 City Transportation Assets Impacted by Flooding .............................................................................................. 2-88
Figure 42 Transit Assets Impacted by Flooding ....................................................................................................................... 2-90
Figure 43 Census Block Groups with No Vehicles per occupied housing unit ............................................................. 2-93
Figure 44 Access from Census Block Group Centroid to City Gateways ........................................................................ 2-95
Figure 45 Access from Census Block Group Centroid to City Evacuation Centers ..................................................... 2-96
Figure 46 Access from Census Block Group Centroid to City Gateways with 100 Year Flood ................................ 2-97
Figure 47 Access from Census Block Group Centroid to City Evacuation C enters with 100 Year Flood ............. 2-98
Figure 48 Access from Census Block Group Centroid to City Gateways with 500 Year Flood ................................ 2-99
Figure 49 Access from Census Block Group Centroid to City Evacuation Centers with 500 Year Flood ........... 2-100
Figure 50 Disadvantaged Communities and 100 -year and 500-year Flood Plains ................................................... 2-102
Figure 51 Low-Income Areas and Flood Plains in the City ................................................................................................ 2-103
Figure 52 Hazardous Material Clean Up Sites and Flood Plains in the City ................................................................ 2-104
Figure 53 Location and Relative Density of Homeless Encampments in the City of San Luis Obispo ............... 2-105
Figure 54 City Resident’s Flooding Concern and Impact ................................................................................................... 2-106 DRAFTPage 242 of 669
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Tables
Table 1 Potential Impact Scoring ................................................................................................................................................ 2-6
Table 2 Adaptive Capacity Scoring ............................................................................................................................................ 2-6
Table 3 Potential Impact Summary ............................................................................................................................................ 2-7
Table 4 City Demographics by Sex, Race, and Age .............................................................................................................. 2-7
Table 5 Housing Cost Characteristics ........................................................................................................................................ 2-8
Table 6 Gross Rent as a Percentage of Monthly Household Income ............................................................................ 2-8
Table 7 Languages Spoken by City Residents ...................................................................................................................... 2-10
Table 8 Social Vulnerability and Environmental Justice Indicators by Census Tract ............................................... 2-14
Table 9 Changes in Average Annual Temperature in City of San Luis Obispo ........................................................ 2-20
Table 10 Changes in Extreme Heat Events in City of San Luis Obispo .......................................................................... 2-22
Table 11 Changes in building energy use through 2099 ................................................................................................... 2-27
Table 12 Heat Health Events through 2099 ............................................................................................................................ 2-31
Table 13 Changes in Average Annual Precipitation and 5 -Year Storm Event in San Luis Obispo County ....... 2-39
Table 14 Changes in Annual Average Area Burned in San Luis Obispo County ........................................................ 2-49
Table 15 Percent Change in Developed Area for WUI Areas within the City 2001 -2016 ......................................... 2-52
Table 17 Changes in Average Annual Precipitation in City of San Luis Obispo ......................................................... 2-70
Table 18 Climate-induced Changes in Peak Stream Flow for the San Luis Obispo Creek Watershed ............... 2-74
Table 19 Change in Connected Floodplain Areas for 9 Analysis Regions from Historic to Future
(median) Conditions. ..................................................................................................................................................... 2-85
Table 20 Change in Connected Floodplain Depths for 9 Analysis Regions from Historic to Future
(median) Conditions. ..................................................................................................................................................... 2-85
Table 21 Transit Stops Impacted by Storm Event ................................................................................................................. 2-89
Table 22 Flood Year and Longest Distances to City Gateways and Evacuation Centers ........................................ 2-101
Table 23 Summary of Existing Plans and Reports .................................................................................................................... 3-1
Table 24 Summary of Vulnerability Scoring ............................................................................................................................... 3-1
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LIST OF ABBREVIATIONS
°F Fahrenheit
°C Celsius
Q10 10-year storm event
Q100 100-year storm event
APG Adaptation Planning Guide
AR Atmospheric River
CALFIRE Department of Forestry and Fire Protection
Cal Poly California Polytechnic State University at San Luis Obispo
Caltrans California Department of Transportation
CDC Center for Disease Control and Prevention
CDD Cooling Degree Day
CDHP California Department of Public Health
CHAT California Heat Assessment Tool
County County of San Luis Obispo
City City of San Luis Obispo
FEMA Federal Emergency Management Agency
GHG greenhouse gas
GIS geographic information system
HDD Heating Degree Day
HHE Heat Health Events
HMP San Luis Obispo County Multi-Jurisdictional Hazard Mitigation Plan
IDF intensity, duration, frequency
IPCC Intergovernmental Panel on Climate Change
OES Office of Emergency Services
OPR Governor’s Office of Planning and Research
PG&E Pacific Gas and Electric
PCTP Pacific Coast tick fever
ppm Parts Per Million
PSPS Public Safety Power Shutoff
RCP Representative Concentration Pathways
Report Climate Change Hazards and Vulnerabilities Report
RTA San Luis Obispo Regional Transit Authority DRAFTPage 244 of 669
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SB Senate Bill
SLO San Luis Obispo
SR State Route
SWAT Soil and Water Assessment Tool
UHI Urban Heat Island
UWMP Urban Water Management Plan
VHFHSZ Very High Fire Hazard Severity Zones
WUI wildland-urban interface
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1 INTRODUCTION
The climate is changing, with the pace of global warming being rapidly increased by human activities. Human -caused
climate change is likely to increase the global average temperature 1.5 degrees Celsius (°C) (2.7° Fahrenheit [F])
between 2030 and 2052 (IPCC 2018). While the global community continues to reduce greenhouse gas (GHG)
emissions moving forward, historic global GHG emissions have already solidified permanent changes to the
environment, bringing with it substantial changes to the world, the state, the region, and the City of San Luis Obispo
(City). Acknowledging the severity of these impacts and the importance of preparedness, the City o f San Luis Obispo
City Council has identified climate adaptation and resilience as a top priority.
The Climate Change Hazards and Vulnerabilities Report (Report) is the City’s primary climate change vulnerability
assessment summary document. The vulnerability assessment included in the Report identifies the City’s exposure to
the effects of climate change, identifies the sensitivity of population groups and community assets to specific climate-
related hazards, analyzes potential climate change impacts, and assesses the City’s existing capacity to address those
impacts. The Report also serves to summarize and synthesize more detailed work being done that focuses on specific
climate-hazards, City resources, or specific climate-related impacts. This Report is a component of the City’s Resilient
SLO project, a community-led initiative to improve community resilience to the worsening impacts of climate change.
It is intended to help identify the specific climate vulnerabilities and impacts that are p rojected to occur in the City
and assist in the development of a comprehensive set of climate adaptation strategies that will be incorporated into
the General Plan Safety Element in compliance with Senate Bill (SB) 379, Government Code section 65302(g)(4).
SB 379, adopted in 2015, requires jurisdictions to integrate climate change adaptation into the general plan safety
element development and update process. The law requires all cities and counties to update their safety elements to
include the assessment of climate change vulnerabilities and adaptation strategies upon the jurisdiction’s next safety
element update. Under Government Code Section 65040.2, the Governor’s Office of Planning and Research is
charged with periodically updating and adopting the State General Plan Guidelines to guide the preparation of
general plans for all cities and counties in California. The 2017 update to the General Plan Guidelines Safety Element
chapter includes an additional focus on preparing communities for long-term climate change impacts (OPR 2017).
The Resilient SLO project follows the four -phase adaptation planning process included in the California Adaptation
Planning Guide, as shown in Figure 1. This Report serves as the culmination of Phase 2 of the project, assessing the
unique vulnerabilities of the SLO community to the impacts of climate change. The findings of this Report will support
development of a set of adaptation strategies (Phase 3) to be included in City’s Safety Element Update.
Figure 1 California Adaptation Planning Guide Adaptation Planning Phases DRAFTPage 247 of 669
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This Report was developed using the best available information regarding climate change projections for the City and
the Central Coast region, relevant information on current efforts to adapt to climate change, and best practices and
guidance provided by the State and other sources specific to climate adaptation planning. The primary resources
used in developing this Report are:
California Adaptation Planning Guide (Cal OES 2019);
Safeguarding California Plan: California’s Climate Adaptation Strategy (CNRA 2018);
Cal-Adapt 2.0;
California’s Fourth Climate Change Assessment (statewide report) (OPR et al. 2018a, 2018b);
California’s Fourth Climate Change Assessment: Central Coast Region Report (2018b);
State of California General Plan Guidelines (OPR 2017);
State Adaptation Clearinghouse in the Integrated Climate Adaptation and Resiliency Program;
San Luis Obispo County Multi-Jurisdictional Hazard Mitigation Plan (San Luis Obispo County 2019a; and
California Department of Transportation (Caltrans) District 5 Climate Change Vulnerability Assessment Summary
Report (Caltrans 2019a); and associated Technical Report (Caltrans 2019 b).
1.1 CLIMATE CHANGE OVERVIEW
The combustion of fossil fuels, among other human activities since the Industrial Revolution in the 19th century , has
introduced GHGs into the atmosphere at an increasingly accelerated rate. Significantly elevated levels of GHG
emissions have intensified the greenhouse effect and led to a trend of unnatural warming of the Earth’s climate, known as
global climate change or global warming. The largest source of GHG emissions from human activities i s the burning
fossil fuels for electricity, heat, and transportation. Climate change, in recent decades, has become a priority issue on
an international, national, and local scale as recent climate data reveal more extreme weather patterns, increased
average global temperatures, and the rapid melting of the Earth’s Artic and Antarctic poles and glaciers.
The global average temperature is expected to increase by 3.7 degrees Celsius (°C) (6.7 to 8.6 degrees °F) by the end
of the century unless additional efforts to reduce GHG emissions are made (IPCC 2014). Human-caused climate
change is currently increasing the global average temperature by approximately 0.2°C (0.36 °F) per decade due to
past and ongoing emissions. While the global average temperature has already begun to increase, the
Intergovernmental Panel on Climate Change (IPCC) has identified an increase of 1.5 degrees °C (2.7 F°) as a threshold
that, if crossed, push many natural systems that sustain life past a dangerous turning point with a more limited ability
to recover (IPCC 2018). Depending on future GHG emissions, average annual maximum daily temperatures in
California are projected to increase between 4.4 and 5.8°F by 2050 and by 5.6 to 8.8°F by 2100 unless significant
reductions in GHG emissions are made (OPR et al. 2018a). Temperature changes in the Central Coast region are
expected to be even more significant, with projections of a 7 to 8°F increase by the end of the century (OPR et al
2018b) if global emissions continue on their current trend .
The state and the City have already begun to experience extreme weather effects, the frequency and intensity of
which have been worsened by climate change (OPR et al. 2018a). Extreme weather effects such as volatility in
precipitation, increased average temperatures, and increased frequency of extreme heat events have led to increases
in the frequency and intensity of human health and natural hazard impacts such as wildfires, droughts, and changes
to regional water supplies.
While the scope of the Resilient SLO project is intended to focus o n local and regional climate impacts, it is important
to recognize that larger scale climate impacts to natural and manmade systems may affect the SLO community and
should be recognized. DRAFTPage 248 of 669
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In September 2021, the IPCC’s Sixth Assessment Report was released. The findings highlight key new insights into the
importance of global climate tipping points, a threshold that, when exceeded, can lead to large changes in the state
of the climate system with one impact rapidly leading to a series of cascading events with vast repercussions. This
new report is set to contain the body’s strongest warnings yet on the subject.
Importantly, the draft report notes that, in terms of solutions, “We need transformational change operating on
processes and behaviors at all levels: individual, communities, business, institutions and governments . We must
redefine our way of life and consumption (Earth.org 2021)”
In 2020, the City adopted the Climate Action Plan for Community Recovery with the goal of achieving carbon
neutrality by 2035 while focusing on using resources more effectively, improving community equity and well -being,
and developing an economy that is set to recover from the impacts of COVID -19. The intent of the science-based
goal is to play a proportional role in achieving global carbon neutrality and inspire similar action regionally, statewide,
nationally and internationally so that global warming is kept between 1.5°C and 2°C. While it remains imperative that
the City implement the Climate Action Plan and reduce GHG emissions to achieve carbon neutrality, it is equally
important for communities to invest in climate change adaptation planning to improve resilience to extreme climate
events that are projected over the 21st century.
1.2 WHAT IS RESILIENCE?
Resilience is the capacity of any entity —an individual, a community, an organization, or a natural system —to prepare
for disruptions, to recover from shocks and stresses, and to adapt and grow from a disruptive experience (Rodin
2014). As has been demonstrated by recent catastrophic wildfire seasons, the more frequent severe storms, the
prolonged drought periods and the longer and hotter summer seasons, the effects of climate change are already
occurring in California and in the Central Coast region. Planning for how to mitigate and adapt to these impacts is
important to ensure the City is able to continue to prosper as a community.
Importantly, the concept of creating community resilien ce goes beyond preparing for the physical environment for
future impacts from climate change and now considers and prioritizes the physical and psychological health of the
population, social and economic equity, and well-being of the community. Developing a resilient community requires
effective risk communication, integration of organizations (both governmental and community-based) in climate
adaptation planning, response, and recovery, and supporting social connectedness for resource exchange, cohesion,
response, and recovery efforts (CNRA 2018). In an effort to identify how the City can not only adapt to climate
impacts but become more resilient and thrive in a more volatile and unpredictable climate, this Report identifies and
discusses both the physical and social vulnerabilities the City has to the impacts of climate change in an effort to
better support the adaptation strategy development process.
The following section (Climate Hazards Assessment) of the Report provides a detailed assessment of four key
climate-related hazards (Temperature and Extreme Heat; Long-Term Drought; Wildfire; and Precipitation and
Flooding) that are projected to affect the City. Section 3 (Vulnerability Scoring Summary) then provides a summary
and ranking of the four climate-related hazards based on the findings of the assessment in Section 2.
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2 CLIMATE HAZARDS ASSESSMENT
This section provides a comprehensive assessment of the City’s vulnerabilities to climate change. It identifies and
characterizes climate-related hazards and other climate effects that are anticipated to affect the City , its residents,
and visitors. The analysis in this section is organized into four distinct hazard categories. These categories are:
Temperature and Extreme Heat
Long-Term Drought
Wildfire
Precipitation and Flooding
It is important to recognize that the City is exposed to other natural and human-made hazards such as seismic
events or hazardous waste. However, these hazards are addressed other planning documents in the City’s Safety
Element and the County Multi-Jurisdictional Hazard Mitigation Plan. This Report assesses hazards that are going
be affected and exacerbated by climate change, focusing specifically on how these hazards are likely to increase in
frequency and severity .
2.1 VULNERABILITY ASSESSMENT METHODOLOGY
For each of the four hazard areas listed above, the analysis follows the vulnerability assessment process outlined in
the California Adaptation Planning Guide and is composed of the four steps outlined below in Figure 2. The following
discussion provides an overview of the methodology used for each step of the vulnerability assessment proces s and
provides context for the discussions of each climate-related hazard in Sections 2.2 through 2.5.
2.1.1 Exposure
The purpose of this step is to understand to what degree the City is vulnerable to impacts from each climate-related
hazard under historic conditions and how changes in climate variables are projected to affect th e hazard. A summary
of the City’s existing exposure to each hazard is provided using information from the Resilient SLO Baseline
Conditions Report (City of San Luis Obispo 2021a).
According to the work of IPCC and research conducted by the State of California , partner agencies, and
organizations, climate change is already affecting and will continue to affect the physical environment throughout
California, including the City. To identify the local impacts of climate change in California, the California Energy
Commission, and the University of California, Berkeley Geospatial Innovation Facility developed the scenario planning
tool Cal-Adapt. The Cal-Adapt tool uses global climate simulation model data downscaled to a local and regional
resolution to identify localized impacts from various climate metrics. Developers of the Cal -Adapt tool selected four
priority global climate models to include in projections provided in th e tool. This analysis uses the average of these
four models to identify changes in temperature and extreme heat events. DRAFTPage 251 of 669
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Source: Cal OES 2019.
Figure 2 California Adaptation Planning Guide Vulnerability Assessment Process
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This analysis uses Cal-Adapt data to evaluate changes in several key climate variables projected to affect the City. The
analysis also identifies at what point over the next approximately 80 years (202 1–2099) changes in these variables will
occur and at what magnitude. This exposure analysis uses three time periods to analyze changes in key climate
variables. Due to annual fluctuations in climate variables, climate data is typically measured on a 30 -year or longer
timescale. Climate variables measured over a shorter time period is typically less accurate and not reflective of long-
term averages (NOAA 2018). The time periods established for this analysis are 30-year time intervals to gather
accurate data on average changes in the climate . This results in overlap among some time periods and a gap between
2064 and 2070. However, the three time periods used in this analysis have been chosen to align with time periods used
in the Cal-Adapt tool and are intended to provide snapshots of how certain climate variables will change over the 21st
century. The three time periods are:
Near-term (2021–2050),
midterm (2035–2064), and
late-century (2070–2099).
The California Adaptation Planning Guide (APG), as well as the Governor’s Office of Planning and Research’s
guidance for State agencies (OPR 2018), provide guidance on choosing appropriate Representative Concentration
Pathways (RCP) scenarios to be included in vulnerability assessment analyses. For analysis of impacts through 2050,
the APG suggests using a conservative approach and selecting the high emissions scenario, to assume a worst-case
scenario but notes that impacts by 2050 under the medium and high scenarios will vary based on local context. As
recommended by the APG, this analysis evaluates near-term and midterm climate change effects and their associated
impacts under the high emissions scenario, as this takes a conservative approach and assumes a worst -case scenario.
Additionally, as observed in the Cal-Adapt data, changes in climate variables during the near-term and midterm
periods are similar under both the medium and high emissions scenarios. Because long-term global GHG emissions
trends are less certain and climate impacts vary more considerably between scenarios during this period, a discussion
of both the medium and high emissions scenarios is included for this timescale (OPR et al 2018a).
FORECASTING ASSUMPTIONS
The projected effects of climate change over the next century will vary depending on global GHG emissions trends.
The Cal-Adapt tool includes global climate simulation model data from two emissions scenarios, known as RCPs, that
were used in the IPCC’s Fifth Assessment Report. The RCPs represent scenarios that estimate the level of global GHG
emissions through 2099. The RCP scenarios used in the Cal -Adapt tool and discussed in the California Adaptation
Planning Guide are the RCP 8.5 (high emissions) scenario, which represents a business-as-usual future emissions
scenario in which global GHG emissions continue to rise through the rest of the century , peaking around 2099, and
resulting in atmospheric CO2 concentrations exceeding 900 parts per million (ppm) by 2100, and the RCP 4.5 (medium
emissions) scenario, which represents a lower GHG emissions future and likely the best -case scenario for climate
impacts, under which GHG emissions would peak in 2040 and then decline through the rest of the century, resulting
in a CO2 concentration of about 550 ppm by 2100. The RCP trends assumed in the analysis are illustrated in Figure 3.
Figure 3 also includes other global emissions scenarios that have been analyzed by the IPCC but are not included in
the Cal-Adapt tool. The RCP 4.5 and 8.5 scenarios have been included in the Cal -Adapt tool because they represent
two important scenarios for future planning. The RCP 8.5 scenario is included to illustrate what climate impacts will
look like if no future action is taken to reduce global emissions. T he RCP 4.5 scenario is included as a potential best -
case scenario for reducing global GHG emissions. The emissions scenarios depend on global GHG emissions trends in
the future and the efficacy of global GHG reduction strategies proposed by the internation al community. DRAFTPage 253 of 669
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Notes: CO2= carbon dioxide; ppm = parts per million; PgC = one billion metric tons of carbon;
RCP = Representative Concentration Pathway.
Source: Goosse et al. 2010
Figure 3 Representative Concentration Pathway Used in Global Climate Model ing
Cal-Adapt also includes 10 global climate models, downscaled to local and regional resolution using the Localized
Constructed Analogs statistical technique. Four of these models have been selected by California’s Climate Action
Team Research Working Group as priority models for research contributing to California’s Fourth Climate Change
Assessment. Projected future climate from these four models can be described as producing:
A warm/dry simulation (HadGEM2-ES),
A cooler/wetter simulation (CNRM-CM5),
An average simulation (CanESM2), and
The model simulation that is most unlike the first three for the best coverage of different possibilities (MIROC5).
2.1.2 Sensitivity and Potential Impacts
This step summarizes population groups and community assets that are sensitive to localized climate change effects.
Changes in climate-related hazards are generally projected to increase in severity, with the potential for climate
change to generate new impacts that communities have not experi enced historically. Using historical data, research
from regional and statewide reports on climate impacts, and input from stakeholders on which sensitive populations
and assets should be prioritized for the analysis, this step identifies sensitive populations and assets and assesses how
they are likely to be impacted by climate change.
As part of the community outreach process for the Resilient SLO project, a specific set of priority assets and functions
were identified for each of the three categories de scribed above. The priorities identified for these three categories
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Resilience Roundtable, a community-led advisory body that is helping the City guide the approach and focus of the
Resilient SLO project and the City’s Safety Element update. The priorities identified through the community outreach
process were then supplemented using hazard mitigation and emergency operation planning resources developed
previously the by City and the County. The priorities identified by the working groups and additionally identified
priority sensitive populations and assets are list below under each category.
The set of sensitive populations, assets, and community functions analyzed in this step are organized into the
following three general categories.
Natural Systems – This category includes systems or system
components of the natural environment (e.g., forests and grasslands, flora and
fauna, stream health) in the City and the surrounding region that are critical to
overall ecosystem health.
o Passive Recreation and Trails (Working Group)
o Open Space and Ecosystem Functions (Working Group)
o Agricultural Production and Industry (Working Group)
o Invasive species and secondary impacts (Working Group)
o Water (water supply, stormwater) (Working Group)
o Urban Tree Canopy (Additional Priority)
Built Environment – This category includes the physical assets that
comprise the City’s built environment (e.g ., roadway network, buildings, utility
systems, stormwater management system) that are critical to supporting normal
community functions in the City.
o Evacuation Routes and Mobility (Working Group)
o Telecommunication Systems (Working Group)
o Building Stock and Energy Efficiency (Working Group)
o Community Spaces for Gathering (Working Group)
o Energy Infrastructure and Outages (Working Group)
o Wildland Urban Interface (Additional Priority)
o Water Supply Reservoirs (Additional Priority)
o Stormwater Management System (Additional Priority)
Community Resilience – This category includes human-focused
systems that provide essential services to residents and visitors in the City and are
critical to maintaining normal community functions (e.g., economic activity,
healthcare system, schools).
o Food Systems and Supply Chains (Working Group)
o Emergency Communications/Misinformation (Working Group)
o Personal Resilience (Health and Finances) (Working Group)
o Governance/Trust (Working Group)
o Community Organizations and Social Networks (Working Group)
o Climate Vulnerable Populations (Additional Priority)
These three categories, marked by their signature color shown above, are discussed throughout this report in relation
to each hazard.
While these three categories are intended to encompass important components of the City and i ts functions, impacts
in these categories are likely to affect one another and result in secondary or compounding impacts. Alongside the
discussion of potential impacts, th e sections below that discuss each hazard also includes a discussion of how some
of the various impacts in these categories may overlap or compound one another. DRAFTPage 255 of 669
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Based on guidance from the California Adaptation Planning Guide, potential impacts from each of the four climate-
related hazards listed above are rated on a qualitative scale comprised of Low, Medium, and High ratings. A
description of each qualitative rating for potential impacts is provided in Table 1.
Table 1 Potential Impact Scoring
Score Potential Impact Scoring Description
Low (1) Impact is unlikely based on projected exposure; would result in minor consequences to public health, safety, and/or other
metrics of concern.
Medium (2) Impact is somewhat likely based on projected exposure; would result in some consequences to public health, safety, and/or
other metrics of concern.
High (3) Impact is highly likely based on projected exposure; would result in substantial consequences to public health, safety, and/o r
other metrics of concern.
Source: CalOES 2020
2.1.3 Adaptive Capacity
Adaptive capacity is defined as the ability of systems, institutions, humans, and other organisms to adjust to potential
damage, to take advantage of opportunities, or to respond to consequences (IPCC 2014). The City, partner agencies,
and community organizations in the City have already taken substantial steps to build resilience and protect the City
from existing climate-related hazards. The purpose of this step is to analyze and summarize the City’s current adaptive
capacity to address and reduce risk from future climate impacts. This step includes a review of the City’s existing policies,
plans, programs, and resources, as well as those from relevant regional and State agencies and organizations that
provide an assessment of the City’s current ability to reduce vulnerability to hazards and adapt to climate change over
the 21st century. Although the City has already taken comprehensive steps to reduce risk from these hazards, climate
change is projected to increase the frequency and severity of climate-related hazards in the future and may exceed the
City’s current capacity to address these hazards or may pose novel threats the City has not encountered historically.
Based on the analysis of current resources and efforts undertaken by the City or partner agenc ies, the City’s adaptive
capacity for each climate-related hazard is rated Low, Medium, or High. High adaptive capacity indicates that
measures are already in place to address the points of sensitivity and impacts associated the specific climate-relate
hazard, while a low rating indicates a community is unprepared and requires major changes to address specific
sensitivities. Adaptive capacity ratings are described in Table 2.
Table 2 Adaptive Capacity Scoring
Score Adaptive Capacity Scoring Description
Low (3) The community lacks capability to manage climate impact; major changes would be required.
Medium (2) The community has some capacity to manage climate impact; some changes would be required.
High (1) The community has high capacity to manage climate impact; minimal to no changes are required.
Source: CalOES 2020
2.1.4 Vulnerability Scoring
This step determines the City’s priority climate vulnerabilities through a vulnerability scoring process. The City’s
vulnerability to each identified impact is assessed based on the magnitude of risk to and potential impacts on City
while considering the current adaptive capacity to mitigate for these impacts. Based on the ratings of potential
impacts and adaptive capacity, an overall vulnerability score has been assigned to each climate -related hazard
category. This scoring helps the City better understand which climate hazards pose the greatest threat and should be
prioritized for future planning efforts. Table 3 presents the rubric used to determine overall vulnerability scores based
on the ratings for potential impacts and adaptive capacity. DRAFTPage 256 of 669
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Table 3 Potential Impact Summary
Vulnerability Score
Adaptive Capacity
Low 3 4 5
Medium 2 3 4
High 1 2 3
Low Medium High
Potential Impacts
Source: CalOES 2020; adapted by Ascent Environmental in 2021
Vulnerability scoring for each climate change effect identified and evaluated in Sections 2.2 through 2.5 is included in
Section 3 which also provides a summary of all climate-related hazards analyzed.
2.2 SOCIAL VULNERABILITY AND ENVIRONMENTAL JUSTICE
This section provides an overview of the sociodemographic characteristics of the City and highlights specific social
vulnerabilities and environmental justice issues that may place certain populations or areas in the City at a
disproportionately higher risk of climate change related impacts. The information in this section is then used, as
appropriate, in each hazard dis cussion, highlighting where and how certain populations may be at increased risk from
climate impacts.
Certain populations in urban areas are particularly vulnerable to a variety of hazards that are likely to be exacerbated
by climate change. Vulnerabilities can include being disproportionately exposed to hazards and environmental
pollution; being more sensitive to impacts because of preexisting health conditions; or having less resources or
opportunities to prepare for and recover from hazard impacts. Vuln erable populations often include persons over the
age of 65, infants and children, communities of color, individuals with chronic health conditions (e.g., cardiovascular
disease, asthma), low-income populations, athletes, and outdoor workers (CDC 2019). More broadly, any trait that
would limit or prevent people from avoiding a hazard, seeking medical attention, or obtaining essential food,
supplies, and/or care in an emergency would make them vulnerable to hazards.
2.2.1 Population Overview
The U.S. Census bureau estimates the City’s population to be 47,459 persons as of July 2019 (U.S. Census Bureau 2019).
Table 4 illustrates the City’s demographics by sex, race, and age according to the U.S. Census. As shown, the majority of
residents identify as white with those identifying as Hispanic being the second largest demographic group. In terms of
youth and elderly populations, 29 percent of City residents are either under 18 years or over 65 years old. The City is
highly educated: 93 percent of the population over 25 years old has at least a high school degree, and 50 percent of the
population over 25 years old has a bachelor’s degree or higher (U.S. Census Bureau 2018).
Table 4 City Demographics by Sex, Race, and Age
Demographic Characteristics City of San Luis Obispo San Luis Obispo County California
Population 47,459 283,111 39,512,223
Male 51% 51% 50%
Female 49% 49% 50%
White alone 84% 89% 72%
Hispanic or Latino 18% 23% 39%
Asian alone 6% 4% 16%
Two or more races 4% 4% 4%
Black or African American alone 2% 2% 7%
American Indian and Alaska Native alone 0.4% 1.4% 1.6% DRAFTPage 257 of 669
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Demographic Characteristics City of San Luis Obispo San Luis Obispo County California
Persons under 5 years 3% 5% 6%
Persons under 18 years 13% 18% 23%
Persons 65 years and older 13% 21% 15%
Source: U.S. Census Bureau 2019
HOUSING COSTS
Overall, the cost of living in the City is high relative to household income. Table 5 provides key information about
housing costs in the City. As shown in Table 6, around 57 percent of renters spend 35 percent or more of their
income on rent (U.S. Census Bureau 2018). Around 6 percent of all families and 14 percent of families with a female
single parent had an income that fell below the poverty level in the span of a year (U.S. Census Bureau 2018).
Table 5 Housing Cost Characteristics
Housing Characteristic Housing Cost
Median monthly cost for owners with a mortgage $2,340
Median monthly cost for renters $1,461 per unit
Median household income $52,740
Source: U.S. Census Bureau 2018
Table 6 Gross Rent as a Percentage of Monthly Household Income
Housing Characteristic Percent of Occupied Units
Less than 15 percent 7%
15 to 20 percent 8%
20 to 25 percent 9%
25 to 30 percent 13%
30 to 35 percent 6%
35 percent or more 57%
Source: U.S. Census Bureau 2018
As illustrated in Figure 4, the City has a substantial low-income population, as mapped consistently with definitions
provided in Assembly Bill 1550, which defines low-income communities as census tracts with median household
incomes at or below 80 percent of the statewide median income or with median household incomes at or below the
threshold designated as low income by the California Department of Housing and Community Development’s list of
state income limits adopted pursuant to California Code Section 5 0093. As demonstrated in Figure 4, this population
is located primarily in the northern and central parts of the City . It is estimated that Cal Poly State University and
Cuesta College students comprise more than one third of the City's population. As a result, students strongly
influence the City’s housing supply and demand. As noted in the City’s Housing Element, although often grouped
into low-income categories statistically, many students can spend more on housing than income data suggests
because of parental support or larger household sizes. By pooling their housing funds, groups of students can often
afford more expensive housing. This contributes to higher rents in San Luis Obispo compared to other parts of the
County (City of San Luis Obispo 2020a).
Research has found that housing affordability is one of the strongest predictors of rates of homelessness in a
community, with higher median rents leading to higher rates of homelessness and higher rates of sheltered homeless
populations. To better understand the issue of homelessness , the U.S. Interagency Council on Homelessness
categorizes homeless individuals in three basic groups: chronically homeless (i.e., people who have experienced long -
term homelessness), episodic homeless (i.e., people who alternate between permanent housing and supportive
housing or shelters), and transitional homeless (i.e., people who become t emporarily homeless because of an event,
such as loss of employment) (U.S. Interagency Council on Homelessness 2009). There are approximately 482
homeless individuals in the City (City of San Luis Obispo 2020a). DRAFTPage 258 of 669
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Source: CalEPA 2020
Figure 4 Low-Income Communities as Defined under Assembly Bill 1550 DRAFTPage 259 of 669
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DISABILITY STATUS
Individuals with disabilities, especially those who are also unemployed or underemployed, are especially vulnerable to
climate hazards largely because they, along with youth and senior populations, often rely heavily on family or caretakers
for transportation and other basic needs (e.g., taking medications, cooking food). Around 9 percent of the City’s total
civilian noninstitutionalized population has a disability, with the majority of these people 65 years and over. Around 35
percent of people 65 years and over in the city have reported having a disability (U.S. Census Bureau 2018).
LANGUAGE
Cultural and linguistic isolation can make it difficult for people to access or understand important information
regarding preparing for and responding to emergency situations. Approximate ly 6 percent of the City’s population
primarily speaks a language other than English and reports that they can speak English less than “very well” (U.S.
Census Bureau 2018). Table 7 includes information about languages spoken in the City as well as what perce ntage of
residents that speak another language do not speak English “very well” and may experience linguistic isolation.
Table 7 Languages Spoken by City Residents
Language Spoken Percentage of Population Percentage of population that speak
English less than “very well”
Speak only English 83% n/a
Speak Spanish 11% 33%
Other Indo-European Language 2.5% 26%
Asian-Pacific Island Language 3% 45%
Other Languages 0.5% 21%
Notes: n/a = not applicable
Source: U.S. Census Bureau 2018
2.2.2 Social Vulnerability Mapping and Environmental Justice
While the City includes sociodemographic characteristics that may place residents at increased risk to climate
impacts, it is important to recognize that these social vulnerabilities are not spread evenly acr oss the City. Populations
with specific vulnerabilities may be concentrated in key areas of the City and have the potential to overlap with key
climate related hazards that place these populations at a disproportionate level of risk from climate impacts. In
general, low-income residents, communities of color, tribal nations, and immigrant communities have
disproportionately experienced some of the greatest environmental burdens and related health problems throughout
the history of the U.S. and in California. These historic inequities are, in the majority of cases, not a coincidence but a
result of inappropriate zoning and negligent land use planning, intersecting structural inequalities, failure to enforce
proper zoning or conduct regular inspections, deed r estrictions and other discriminatory housing and lending
practices, limited political and economic power among certain demographics, the prioritization of business interests
over public health, development patterns that tend to concentrate pollution and en vironmental hazards in certain
communities, and the placement of economic and environmental benefits in areas outside of disadvantaged
communities (California Environmental Justice Alliance 2017).
Based on the State’s definition of disadvantaged communitie s, no census tracts within the San Luis Obispo region are
designated as disadvantaged communities. However, the San Luis Obispo Council of Governments (SLOCOG) has
created a regional definition of disadvantaged communities to better compete for grant funding, distribute funds
more equitably, and meet the state and federal environmental justice requirements. The Disadvantaged Communities
Assessment was approved by the SLOCOG Board for use in the 2023 RTP and the 2022 Programming Cycle on June
2nd, 2021. DRAFTPage 260 of 669
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In the San Luis Obispo Region, disadvantaged communities are defined as disproportionately burdened areas that
are economically distressed and/or historically underrepresented as a part of the local government process. The
Disadvantaged Communities Assessment identifies 13 variables that address a wide range of socioeconomic and
population-based factors to geographically define these disproportionately -burdened areas. The 13 variables are:
Racial Minority
Ethnic Minority
Disability Status
Household Income
Free or Reduced-Price Meals
Educational Attainment
Language Proficiency
Renter Affordability
Housing Ownership Affordability
Older Adults: Age 75 Years and Older
Youth: Age 15 Years and Under
Households with No Vehicle Available
Households with No Computing Device Available
Similar to the SLOCOG assessment of disadvantaged communities, the Public Health Alliance of Southern California
has developed the California Healthy Places Index (HPI). The California HPI provides an interactive map, graphs, dat a
tables, and a policy guide to examine local health factors and compare local conditions to those across the state.
Climate health vulnerability indicators are built into the HPI by incorporating climate -related hazards data layers into
the mapping (e.g., air conditioning access, public transit access); incorporating select climate -resiliency metrics into
the HPI score, which combines 25 community characteristics into a single indexed score to describe a community’s
overall health; and addressing climate challenges in the policy guide.
The HPI score for the City combines 25 community characteristics across eight areas (i.e., economic, social, education,
transportation, neighborhood, housing, clean environment, and health care) into a single indexed score correlated to life
expectancy at birth. The HPI score ranking for the combined census tracts in the City places it in the 61st percentile,
meaning it has healthier community conditions than 61 percent of other California census tracts. Certain geographic
areas and populations may be more vulnerable than others, by identifying these specific populations or geographic
areas, the City can work to address these vulnerabilities and, in turn, make the whole community more resilient.
Compared to the City’s overall HPI score, the City is doing particularly well in terms of education, performing better
than 78 percent of other California census tracts in preschool enrollment and residents with a bachelor’s degree or
higher. However, the City ranks lower in terms of the economic factors score (39th percentile overall), which includes
factors such as median household income, unemployment rate, and population with an income exceeding 200
percent of federal poverty level. The City also ranks low in terms of the housing fa ctors score (17th percentile overall),
which includes indicators such as low-income homeowners and renters with a severe housing burden (HPI 2020). This
summary provides highlights of the City overall HPI score. To see all information on individual indicat ors, visit the
California HPI website (https://map.healthyplacesindex.org/).
Figure 6 below includes the main census tracts that comprise the City. Table 8, which corresponds with Figure 6, includes
a set of sociodemographic characteristics for each of the City’s census tracts. Figure 5 also includes the HPI scoring scale
for each census tract in the City, highlighting the portions of the City with lower scores that may be more vulnerable to
climate impacts. The HPI scores for each census tract can be compared across the state to paint an overall picture of
health and well-being in each census tract relative to the rest of California. For example, a census tract HPI score of 21
means that that tract has healthier community conditions than just 21.5 percent of other California census tracts. This
means the lower the HPI score equates to, in general, less healthy living conditions and health outcomes for residents
and potentially more climate vulnerability. DRAFTPage 261 of 669
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Sources: Data received from SLOCOG in 2021 and from CBEC Engineering in 2020, and downloaded from City of San Luis Obispo in 2020 and
County of San Luis Obispo in 2020
Figure 5 Regionally Defined Disadvantaged Communities in the City of San Luis Obispo DRAFTPage 262 of 669
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Sources: Data downloaded from US Census in 2019, City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 6 Census Tracts in the City of San Luis ObispoDRAFT
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Table 8 Social Vulnerability and Environmental Justice Indicators by Census Tract
Name
Cal Poly
Neighbo
rhood
North
Monterey
Street and
Johnson
Avenue
Sinsheimer
Neighborh
ood
Downtown
SLO and Mill
Street
Historic
District
South
Downtown
SLO and
Railroad
District
Margarita
Avenue
Neighborhood
Foothill
Boulevard
Neighborhood
Laguna Lake
and Los
Osos Valley
Road
West of
South
Higuera
South Broad
Street
Neighborhood
Census Tract 109.02 110.02 110.01 111.01 111.02 111.03 112 113 115.01 115.03
Healthy Places Index Score 27.6 70.5 72.7 55.5 69.6 37.4 50.9 68.4 60.4 84.6
Latino 12% 9% 16% 15% 16% 25% 10% 18% 17% 9%
Black <1% <1% <1% 2% <1% 2% <1% 0.01 2% <1%
Asian 6% 4% 5% 3% 3% 3% 5% 7% 4% 4%
Poverty Level 80% 51% 30% 49% 42% 50% 59% 38% 32% 22%
Linguistic Isolation 2% 2% 4% 1% 3% 8% 1% 8% 4% 0%
Outdoor Workers <1 2% 2% 4% 4% 3% 2% 3% 5% 2%
Elderly Populations 3% 8% 20% 9% 10% 17% 13% 14% 17% 12%
Youth Populations 2% 2% 7% 2% 3% 5% 3% 3% 5% 6%
Disabled Population 3% 4% 12% 7% 11% 11% 8% 10% 15% 7%
Tree Canopy 5% 1% 7% 6% 3% 4% 9% 9% 5% 3%
Park Access 76% 78% 93% 100% 100% 94% 60% 99% 100% 93%
Supermarket Access 33% 67% 30% 83% 99% 40% 58% 53% 92% 32%
Renter Housing Cost Burden 70% 42% 22% 29% 25% 35% 70% 34% 11% 41%
Active Commuting 31% 20% 11% 35% 23% 21% 22% 13% 9% 6%
CalEnviroScreen Score 9.89 14.99 6.69 11.85 10.95 26.9 15.86 16.58 12.86 10.9
Notes: n/a = not applicable
Source: California Healthy Places Index 2021; U.S. Census Bureau 2017 DRAFTPage 264 of 669
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Sociodemographic Characteristic Definitions
Latino – Percent of population in the census tract that identify as Latino.
Black – Percent of population in the census tract that identify as Black or African American.
Asian – Percent of population in the census tract that identify as Asian.
Poverty Level - Percent of people in the census tract earning less than 200% of the federal poverty level (Federal
poverty level = $12,880 per individual in 2021). 200% is often used to measure poverty in California due to high
costs of living.
Linguistic Isolation – Percent of households in the census tract that do not have one or more persons 14 years or
older who speaks English well.
Outdoor Workers - Percent of adults (over 16) in the census tract who work outdoors.
Elderly Populations - Percent of population in the census tract under 5 years old.
Youth Populations - Percent of population in the census tract under 5 years old.
Disabled Population - Percent of people in the census tract with access and functional needs (a physical or
mental disability).
Tree Canopy - Percent of land in the census tract has tree canopy (weighted by number of people per acre).
Park Access - Percent of people in the census tract who live within walkable distance (half-mile) of a park or open
space greater than 1 acre.
Supermarket Access - Percent of land in the census tract that reside less than 1/2 mile from a supermarket/large
grocery store.
Renter Housing Cost Burden - Percent of low-income renters in the census tract who pay more than 50 percent
of their income on housing costs.
Active Commuting - Percent of workers (16 years old and older) in the census tract commute to work by transit,
walking, or cycling.
CalEnviroScreen Score – CalEnviroScreen score which identifies communities disproportionately burdened by
multiple sources of pollution and with populati on characteristics that them more sensitive to pollution. A n area
with a high score is one that experiences a much higher pollution burden than areas with low scores , with scores
(0 -100) being compared across all census tracts in the state.
As shown in Figure 6 and Table 8, the city includes several census tracts which include both sociodemographic
characteristics and characteristics of the built environment that make the populations in these census tracts more
vulnerable to climate-related hazards and may be at a larger disadvantage in their ability to become more resilient to
the impacts of climate change. However, as shown in Table 8, other census tracts in the City display specific
characteristics that may make those residents particularly vulnerable to certa in climate related hazards and should
not be overlooked.
Margarita Avenue Neighborhood (Census Tract 111.03) stands out as a particularly vulnerable area of the City and
includes the second lowest HPI score and highest CalEnviroScreen score. Notable chara cteristics of this area that
make it particularly vulnerable , compared to the rest of the city, include a high percentage of minority residents, a
high percentage of elderly and disabled residents, a high percentage of residents experiencing linguistic iso lation, low
access to supermarkets and grocery stores, and 50 percent of residents earning less than 200 percent of the federal
poverty level. The West of South Higuera neighborhood (Census Tract 115.01) also stands out as a particularly
vulnerable area of the City to climate impacts. Notable characteristics of this area that make its residents particularly
vulnerable, compared to the rest of the city, include a high percentage of elderly and disabled residents, the highest
percentage of outdoor workers in the City, and a high percentage of Latino residents who are generally more DRAFTPage 265 of 669
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vulnerable to climate impacts (Natural Resource Defense Fund 2016) and may not have the same level of access to
emergency resources of information.
The analysis of each hazard also takes into account the information on social vulnerabilities presented above to
assesses how populations in different areas of the City are vulnerable to specific hazards.
Figure 7 includes the location and relative density of homeless encampments in the city. The city’s homeless
population are particularly vulnerable to climate -related hazards with less access to shelter and resources to protect
themselves during emergency events (e.g., flooding, heat waves). Similar to the sociodemographic trends prevale nt in
some areas of the City, which make them particularly vulnerable to climate -related hazards, the locations of the
homeless encampments identified in Figure 7 are also identified as areas in the City with particularly vulnerable
populations.
2.2.3 Community-Based Adaptative Capacity
As discussed in 2.1.3, adaptive capacity is defined as the ability of systems, institutions, humans, and other organisms to
adjust to potential damage, to take advantage of opportunities, or to respond to consequences (IPCC 2014). Alongside
the steps the City and partner agencies have already taken protect the City from existing climate-related hazards, it is
important to recognize the role community organizations and informal social networks can play in building adaptive
capacity to the impacts of climate change.
SOCIAL NETWORKS AND SOCIAL COHESION
Aside from resources provided by the City or other agencies to help mitigate the impacts on residents and businesses
during these events, social cohesion can play an important rol e in helping protect residents, particularly vulnerable
populations, during climate-related disasters. Social cohesion, generally understood as the extent of connectedness
and solidarity among groups in society or community, is one of the strongest indicators of resilience during disaster
events as well as in post-disaster recovery efforts (Townshend et al. 2015). Important indicators of social cohesion,
from the this research include:
Belonging versus isolation, which means shared values, identity, feelin gs of commitment;
Inclusion versus exclusion, which concerns equal opportunities of access;
Participation versus non-involvement;
Recognition versus rejection, which addresses the issue of respecting and tolerating differences in a pluralist
society; and,
Legitimacy versus illegitimacy (Jenson 1998).
An important component in remaining resilient to the impacts of climate change and climate -related disasters is the
post-disaster recovery period. As noted in research on the topic, a focus not only of the phys ical rehabilitation of the
built environment but on the addressing the emotional and mental health impacts of disasters is needed to ensure a
successful community recovery during the post -disaster period. The emotional and mental health impacts of disaster s
can be addressed though various types of social cohesion including social and support networks (including access to
social support in times of need), social participation (as the obverse of social isolation and being cut off from
relationships providing friendship and company), and community engagement (including volunteering which draws
people together to work for the benefit of others) (Townshend et al. 2015). While measuring the degree of social
cohesion present in the City is not possible at this poin t, this subject is discussed here to emphasize the importance
of social cohesion in increasing community resilience to the impacts of the climate change. Social cohesion here is
highlighted as important component of c ommunity-based adaptative capacity and is discussed, as appropriate, in the
discussions on specific climate -related hazards.
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Sources: City of San Luis Obispo in 2021
Figure 7 Location and Relative Density of Homeless Encampments in the City of San Luis Obispo DRAFTPage 267 of 669
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RESILIENT SLO COMMUNITY PRIORITIES SURVEY
The effects of climate change are already being felt by community members. In an effort to gather input on overall
community priorities regarding climate-related hazards, concerns related to climate change impacts, experience with
past hazard events and response efforts, and priorities for local action, a community priorities survey was developed and
provided to community residents. The survey, consisting of 19 questions, was open from August 31, 2020 – October 11,
2020 and had 328 responses. Highlights from the survey results have been included in this Report to help better
understand the community’s priorities regarding climate-related hazards and how the residents may already be affected
climate-related hazards. The survey results are also included in the discussion on specific climate-related hazards.
As part of the survey, participants were asked what climate -related impact they were most concerned about. Figure 8
illustrates the responses to this question by age group. As shown in Figure 8, respondents were most concerned
about wildfires and associated poor air quality events. Leading up to and during the survey response period, the City
experienced poor air quality from several wildfires in the surrounding region, which may have influenced su rvey
results. The large majority of respondents were also concerned about drought, increasing temperatures, and heat
wave events and much less concerned about flooding and sea level rise. Survey results for this question also highlight
that respondents in the 18-24 year old age cohort were the most concerned about almost all climate issues. To
explore the full results of the community priorities survey, please refer to Baseline Conditions Report
Sources: Resilient SLO Community Priorities Survey
Figure 8 City Resident’s Climate Concern by Age
COMMUNITY-BASED ORGANIZATIONS
Community-based organizations are generally understood as public or private nonprofit organization s that represent
one or more segments of a community and/or provide educational or other community services to individuals or
specific segments of the population. Climate-related hazards can also affect the ability of community-based
organizations to operate and provide services to the communities they serv e. Community-based organizations also
play an important role in providing a wide variety of services to any community both during disaster and post -
disaster recovery periods as well as during non -disaster periods (Tyler and Moench 2012). In many cases, community-
based organizations provide services to a communities most vulnerable population and as a result are the institutions
most in touch with the day-to-day needs and concerns of these populations during both disaster and non -disaster
periods (Murray and Poland 2020). There is a comprehensive network of organizations in the city and the County that
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Drought and
Decreased
Water Supply
Flooding and
Storm Damage
Hotter
Temperatures
and Heat
Waves
Sea Level Rise Wildfires Wildfire SmokePerecnt of RespondentsClimate Impact
CLIMATE CONCERN BY AGE
18-24
25-34
35-44
45-54
55-64
Above 65
Total Responses = 328 DRAFTPage 268 of 669
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provide a wide variety of services to SLO community residents and visitors. In June 2020, a brief survey was sent out
to community-based organizations in the C ity to better understand how these organization’s operations were being
affected by climate-related hazards and what responses were being taken to better prepare for the impacts of
climate change. A total of eight community organizations responded to the s urvey. Figure 9 includes the results from
two key questions in the survey, highlighting which climate -hazards community-based organizations have been
affected by and which hazards they are concerned will affect their operations. The survey also asked what actions are
being taken by the organizations to better prepare for climate changes. These results will be incorporated in the
resilience strategy development process of the Resilient SLO project.
Figure 9 Climate -Related Hazard Impacts on Community Organizations in the City of San Luis Obispo
2.3 TEMPERATURE AND EXTREME HEAT ANALYSIS
This section discusses future increases in temperature and extreme heat in the City and analyzes how these changes
are likely to impact the City and its population as well as highlighting what capacity the City and partner agencies
already have in place to address future heat-related impacts.
2.3.1 Future Exposure to Temperature Increases and Extreme Heat
The City is characterized by a Mediterranean climate. While the Ci ty is generally considered to have a mild climate,
historically unseasonably warm periods and cold spells have been observed. According to Cal-Adapt, during the
historic period (1961–1990), the annual average maximum temperature in the City was 71.1°F and the annual average
minimum temperature was 43.7°F (CEC 2019a). The annual maximum and minimum daily temperatures are calculated
by averaging daily values of maximum and minimum temperatures for the full year, which is then averaged over a
thirty-year time-period to account for year-to-year variability.
Although the City has not historically experienced many extreme heat conditions, the City is likely to experience
increased sensitivity to extreme temperatures because residents are not acclimatized to or pre pared for extreme heat
conditions, even if increases are relatively mild compared to other parts of the state . Extreme heat events are
described in this section in terms of their intensity (i.e., average maximum temperature), frequency (i.e., how often
they occur), time of year in which they occur, and duration (total number of consecutive extreme heat days). Figure 10
includes the average annual maximum and minimum temperatures for the City from 1926 through 2018.
0
2
4
6
8
Wildfire and associated
impacts
Increased Temperatures
and Extreme Heat
Large Storm Events and
Flooding
Long-Term Drought None of theseNumber of ResponsesClimate Hazard
HAZARD IMPACTS ON SLO COMMUNITY
ORGANIZATIONS
Which of the following climate change impacts are you concerned about affecting your organization and/or the
populations you serve?
Which of the above-mentioned climate-related hazards has your organization been personally affected by in the past
1-3 years?DRAFTPage 269 of 669
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Sources: Cal Poly 2020
Figure 10 Average Annual Maximum and Minimum Temperatures in the City (1926-2018)
AVERAGE TEMPERATURE
As shown in Table 9, both annual maximum and minimum are projected to increase throughout the 21st century. The
average annual maximum temperature in the City is projected to increase to 71.6°F in the near-term and 73.1°F in the
midterm under the high emissions scenario. The average annual maximum temperature is projected to increase to
73.1°F and 75.6°F in the late-century period under the medium and high emissions scenarios, respectively. The
average annual minimum temperature in the City is projected to increase to 48.7°F in the near-term and 49.7°F in the
midterm under the high emissions scenario, and the late-century average annual minimum temperature is projected
to increase to 50.1°F and 52.7°F under the medium and high emissions scenarios, respectively (CEC 2019a). Increased
temperatures in the City will influence secondary climate effects, including extreme heat e vents, wildfire, and drought.
Table 9 Changes in Average Annual Temperature in City of San Luis Obispo
Geography Average Annual
Temperature
Historic Average
Annual Temperature
(1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Medium
Emissions
High
Emissions
City of San Luis
Obispo
Maximum Temperature (°F) 68.4 71.6 73.1 73.1 75.6
Minimum Temperature (°F) 45.7 48.7 49.7 50.1 52.7
San Luis Obispo
County
Maximum Temperature (°F) 69.8 72.9 74.3 74.7 77.3
Minimum Temperature (°F) 42.2 45.4 46.6 46.9 49.8
Notes: °F = degrees Fahrenheit; RCP = Representative Concentration Pathway.
Source: CEC 2019a
Figure 11 illustrates the projected change in average annual maximum temperature in the city and in San Luis
Obispo County (County) in the near-term and midterm periods under the high emissions scenario and average
annual maximum temperature in the late-century period under both emissions scenarios. As shown in the Figure
11, the average annual maximum temperature is expected to rise through the late-century period under both
emissions scenarios . As shown in Table 9, the County compared to the city, has had slightly higher maxi mum and
minimum temperatures historically with th is trend continuing under both emissions scenarios as temperatures
continue to rise in both the city and the County . This difference is also reflected in Figure 11, which shows the City
experiencing smaller increases in annual average maximum temperatures compared to northern and eastern
portions of the County. DRAFTPage 270 of 669
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and downloaded from Cal-Adapt in 2021
Figure 11 Changes in Annual Average Temperature in San Luis Obispo County through 2099 DRAFTPage 271 of 669
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EXTREME HEAT EVENTS
The Cal-Adapt tool provides estimates of future instances of extreme heat events. Extreme heat events include
extreme heat days and heat waves. Cal-Adapt defines an extreme heat day as a day when the daily maximum
temperature exceeds the 98th historical percentile of daily maximum temperatures based on observed data from
1961–1990 between April and October. Heat wave events are characterized as periods of sustained extreme heat and
are defined by Cal-Adapt as four or more consecutive extreme heat days.
The extreme heat threshold for the city is 89.6°F, meaning 98 percent of all recorded temperatures in this period were
below 88.6°F. Historically (1961-1990), the city experienced an average of four extreme heat days per year. As a result
of rising temperatures from climate change, the city is projected to experience up to 7 extreme heats days annually in
the near-term and 10 extreme heat days annually in the midterm under the high emissions scenario. In the late-
century period, the city is projected to experience up to 10 extreme heat days annually under the medium emissions
scenario and 18 extreme heat days annually under the high emissions scenario (CEC 2019b). As shown in Table 10, the
number of extreme heat days is already increasing from historic averages and will continue to increase through the
late-century under both emissions scenarios . The city is already beginning to experience increases in extreme heat
with a new September record high temperature of 117 °F being set on September 6th, 2020 (NOAA 2021).
Table 10 Changes in Extreme Heat Events in City of San Luis Obispo
Annual Averages Historic Annual
Averages (1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Medium
Emissions High Emissions
Number of Extreme Heat Days 4 7 10 10 18
Number of Heat Waves 0.2 0.3 0.4 0.4 1.3
Number of Days in Longest Stretch of
Consecutive Extreme Heat Days 2.6 2.8 3 3.4 4.6
Notes: RCP = Representative Concentration Pathway; Extreme Heat Day = day with maximum temperature above 89.6°F; Heat Wave = four or
more consecutive extreme heat days
Source: CEC 2019b
While heat waves have historically been infrequent in the City, with a
historical average of less than one heat wave annually, climate change is
expected to increase the frequency of heat waves. Under the high
emissions scenario, the City is projected to still experience less than one
heat waves per year in the near-term and in the midterm. In the long
term, the City is projected to experience less than one heatwave per year
under the medium emissions scenario and 1.3 heat waves per year under
the high emissions scenarios.
The average number of days in the longest stretch of consecutive extreme heat days per year is also projected to
increase. Historically, the longest stretch of consecutive extreme heat days lasted for an average duration of
approximately two-and-a-half days. The longest stretch of consecutive extreme heat days is projected to increase only
slightly in the near-term and 3 days in the midterm under the high emissions scenario. In the late century, the duration
is projected to increase to an average of 3.4 days under the medium emissions scenario and 4.6 days under the high
emissions scenario (CEC 2019b). The timing of extreme heat days is also projected to change over the 21st century with
more extreme heat days and heat wave events occurring earlier in the year (April through May) and more severe events
occurring in the historically hot months of September and October (CEC 2019b). The projected number of heat waves
and number of days in the longest stretch of consecutive extreme heat days is shown in Table 10.
Extreme Heat Definitions
Extreme Heat Day = Day with
maximum temperature above
89.6°F
Heat Wave = Four or more
consecutive Extreme Heat Days
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2.3.2 Extreme Heat Sensitivities and Impact
This section discusses the City’s existing sensitivities to extreme
heat and analyzes potential impacts to City with impacts
discussed in the three general impact categories (e.g., Natural
Systems, Built Environment, Community Resilience).
EXTREME HEAT AND NATURAL SYSTEMS
Open Space and Ecosystem Functions
Increases in annual average maximum and minimum
temperatures are likely to alter suitable habitat for specific flora
and fauna in the City, particularly in the City’s recreation and
open space areas. In general, plant species in the Central Coast mountain ranges in or near the city will shift upslope
to track warming temperatures while, in the lowlands, species will move north ward over the 21st century. The City’s
designated open space areas are comprised of a of a mixture of vegetation types including oak woodland, grassland,
coastal sage scrub, and chaparral. Changes in annual average temperatures as well as long-term drought periods are
projected to place increased pressure on these vegetation types. Invasive species have become more common in
coastal sage scrub communities and compete with native coastal sage scrub species inc luding commercial cultivars of
the Monterey Pine (Pinus radiata) from New Zealand. However, it is unclear what effect climate change will have on
invasive species in these open space areas (OPR et al. 2018b).
Many of the open spaces in and around the city also include inland grasslands. Historically, the duration and intensity
of annual droughts in California varies substantially with elevation, latitude, distance to coast, and local soil
characteristics. However, it is projected that most grassland species should be adaptive to tolerate climate extremes
and variability (OPR et al. 2018b). As noted in the Central Coast Region Report, future changes in precipitation and
drought will impact grasslands and wildflowers on the Central Coast and will be dependent on 1) the proximity to
coast, 2) the relative proportion of native to exotic, and perennial to annual species.
Currently, the city has an extensive urban tree canopy with approximately 20,000 public trees on designated public
property within the city limits. The City’s tree canopy provides key benefits to residents and business owners including
shading, traffic calming, beautification, and carbon sequestration. However, due to shifts in annual average minimum
and maximum temperatures in the future, the urb an tree canopy may be threatened, with some tree species no
longer suitable given future minimum and maximum temperature thresholds. Research indicates that increases in
temperature result in decreased photosynthesis and tree growth, and subsequently less carbon sequestration
potential, as well as elevated incidence of pests (Meineke et al. 2016). Research on the impact of climate change on
street trees in 16 California cities indicates that certain tree species that may be less suitable under future climate
conditions may be more resilient when they are part of urban tree network. This is because urban tree networks are
managed by staff which typically includes irrigation and pest management (McBride and Laćan 2018), two important
factors that affect the suitability of various tree species under future climate conditions. The combined urban heat island
effect as well as increase in temperatures due to climate change will also place increased heat stress on the City’s urban
tree canopy (McBride and Laćan 2018).
Invasive Species
As temperatures have increased over the past decade or more, observations have shown that invasive species have
become more common in coastal sage scrub communities and compete with native coastal sage scrub species with the
potential for coastal sage scrub habitats to convert to grasslands after fires, grazing, or nitrogen deposition. However, as
noted in a recent study, while climate change is projected to affect coastal sage scrub communities, anthropogenic land
use changes are likely to be a stronger indicator of effects on this habitat (Riordan and Rundel 2014). DRAFTPage 273 of 669
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In terms of forests and tree species in and surrounding the City, climate change’s impacts on physical conditions in
Central Coast forests will interact with biotic factors such as insect and disease outbreaks alongside changes in
temperature and precipitation. The increasing presence of non-native species in the City’s riparian areas also creates
competing demand for water resources alongside native popul ations of plant species. For the last several decades,
Sudden Oak Death has affected coast live oak, canyon live oak, California black oak, Shreve oak, and the closely
related tan oak. During wet weather, spores of the disease of (Phytophthora ramorum) are produced on infected
leaves, which can be dispersed by wind or via transported soil transported by humans (e.g., hikers, bikes) to infect
new hosts. Climate models suggest broad scale movement Sudden Oak Death into California’s North Coast by 2030,
but less toward the southern portions (e.g., San Barbara County and San Luis Obispo County) of the Central Coast
because of drier conditions there (Meentenmeyer et al. 2011).
Agriculture
Agricultural production is a prominent industry in the County of San Luis Obispo, including a thriving wine industry.
The City also includes some agricultural land uses most notably the San Luis Ranch and the City Farm, a community-
based urban farm hub, both located in the southern portions of the city west of US 101. The agricultural industry is
highly sensitive to climate impacts including specific climate variables such as amounts, forms, and distribution of
precipitation and changes in temperatures. Decrease in water availability due to long -term drought can affect crop
yields and areas suitable for growing (Tanaka et al. 2015).
Increases in temperature, along with the frequency of extreme heat events and heat waves, has the potential to affect
livestock operations in the County. Higher temperatures will lead to increased rates of evaporation of surface waters and
evapotranspiration in plants, resulting in decreased moisture content of soils. These effects will lead to increased
demand for irrigation to water crops. Warmer nighttime temperatures will reduce or eliminate the required number of
“chill hours” that certain crops (e.g., fruit trees) need to bud (Union of Concerned Scientists n.d.). Strawberry production
accounts for approximately 26 percent of total crop value in the County (County of San Luis Obispo 2018). It is projected
that increases in temperatures caused by climate change could decrease yields of California strawberries by about 10
percent by 2050 and up to 43 percent between 2070 and 2099 (USDA 2016). Crop loss of this magnitude would result in
significant loss of tax revenue to the County and result in impacts to employment opportunities for agricultural workers.
Additionally, changes in temperatures will alter the range of crop-damaging pests and microbial diseases, which could
increase the susceptibility of certain crops to predation, increased spoilage, reduced nutritional content, and other
damage. Livestock operations, which accounts for approximately 3 percent of total crop value in the County, could also
be subject to heat stress, which can result in reduced livestock pregnancy rates, increased length of time needed to
meet market weight, and reduced milk production (CNRA 2014:24).
Total yields for wine grapes may be reduced due to warmer winters in the future. Changes in temperature can also
affect plant diseases, insects, and invasive weeds (Pathak et al. 2018). Because the City relies heavily on tourism including
wine and vineyard-based tourism, impacts on agriculture and the wine industry due to climate change in the County
could have negative economic impacts for the City and businesses. There are over 250 wineries throughout Paso
Robles, Edna Valley, and other areas of the County that are national and international tourist destinations. The grape
and wine industry has a large influence on agricultural production in the County. Grapes alone accounted for
approximately 27 percent of all crop value in 2018, while the County produced one billion dollars in total crop value,
demonstrating the significance of agriculture in supporting the County’s economy (County of San Luis Obispo 2018).
Key Findings and Policy Considerations
Changes in temperature and extreme heat are likely to have negative impacts on the City’s tree canopy with
some tree species no longer suitable for future minimum and maximum temperatures. Any future policies
focused on improving the City’s tree canopy or green spaces to mitigate the urban heat island effect should
carefully consider what plant and tree species will be suitable for future climate conditions.
Climate change is projected in invasive species in the City’s open spaces, affecting coastal sage s crub habitats as
well as the City’s oak species from Sudden Oak Death. DRAFTPage 274 of 669
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Regional impacts on the agriculture and viticulture industries from shifting temperatures have the potential
impact the City via decreases in wine and vineyard-based tourism, with the City relying heavily on revenue and
employment opportunities in these industries. Resilience strategies focused on economic impacts should
consider potential impacts on viticulture vineyard-based tourism and potential diversification of the City’s tax
revenue sources and employment industries.
EXTREME HEAT AND THE BUILT
ENVIRONMENT
Urban Heat Island
Although the city’s Mediterranean climate includes high
temperatures during summer and fall months, the city’s urban
land use patterns can intensify periods of extreme heat through
the “urban heat island” effect. The urban heat island effect is
generally understood as the phenomenon of urban areas being
significantly warmer than surrounding rural areas because of
human activity and land use patterns in the built environment. Several factors contribute to the urban heat island
effect, including land use patterns; the presenc e of large-paved areas (e.g., roads and parking lots); traffic from high-
volume roadways (Zhu et al. 2017), impervious surfaces (e.g., roofs). Conversely, the presence of vegetation and trees
in urban environments increases evapotranspiration in which water is released form plants in its gas vapor form and
has a cooling effect on the surrounding air.
SLOCOG developed a regional definition for disadvantaged communities. Disadvantaged communities are
disproportionately burdened areas that are economically dis tressed and/ or historically underrepresented as a part of
the local government process. SLOCOG examined 13 variables, such as racial and ethnic minority, disability status,
language proficiency, renter affordability, and household income. Many of these in dicators also result in increased
susceptibility to extreme heat impacts. To show how the urban heat island effect may further exacerbate projected
heat impacts on the city, including vulnerable populations, Figure 12 identifies SLOCOG identified disadvantaged
community areas, as well as the locations of critical facilities for vulnerable populations.
As shown in Figure 12, areas in the city with an increased concentration of commercial and industrial land uses have
above-average surface temperatures. Notable urban heat island hotspots in the city include:
the Service and Manufacturing, Office, and Business Park land uses near Tank Farm Road and South Higuera Street
the Neighborhood Commercial land uses near Broad Street and Tank Farm Road
some Commercial land uses along the northern portions of Monterey Street in downtown San Luis Obispo (SLO)
Notably, the urban heat island hotspot along South Higuera Street is directly adjacent to residential land use to the
east of South Higuera Street and north of Prado Road likely resulting in disproportionate impacts on these residential
areas including increased energy demand for cooling .
Additionally, as shown in Figure 12, southern portions of the city include far less tree cover than areas near the
downtown and the Laguna Lake area to the west of US 101, which is likely contributing to urban heat island hotspots
in these areas. This include the Margarita Avenue Neighborhood (Census Tract 111.03) and the West of South Higuera
Neighborhood (Census Tract 115.01) which have four and five percent tree cover, respectively, which is lower than
many other parts of the City. Southern portions of the city including areas adjacent to southern portions of Broad
Street and Tank Farm Road include newer residential and commercial developments which include younger trees and
vegetation. This may reduce potential urban heat island effects as vegetation and the tree canopy increase in these
areas in the future. DRAFTPage 275 of 669
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Source: Data received and downloaded from City of San Luis Obispo and the Trust for Public Land.
Figure 12 Urban Heat Island Effect and Tree Cover in the City DRAFTPage 276 of 669
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Buildings and Energy Use
Changes in annual average temperature and extreme heat events are likely to effect buildings primarily through
changes in energy use as well as disproportionate impacts on individuals residing in units that do not have air
conditioning. Cal-Adapt provides data on the shifts in Cooling Degree Days and Heating Degree Days, which are
measurements used to assess the energy demand needed for cooling and heating buildings in different climate
zones throughout California. A degree day does not equate to a single day of the year but r ather compares the mean
(the average of the high and low) outdoor temperatures recorded for a location to a standard temperature (i.e., 65°F).
For example, if the average temperature for a day is 80°F, the day has 15 Cooling Degree Days (80 – 65 = 15). Degree
days are used in the State’s Title 24 Building Energy Efficiency Standards to help design the energy demand needed
for heating and cooling in the various climate zones throughout the state. To illustrate how climate change is likely to
affect energy demand for heating and cooling in the future, Table 11 includes the relative shift in Cooling Degree
Days and Heating Degree Days in the city through 2099.
Table 11 Changes in building energy use through 2099
Impact Impact Type
Percent Change in Energy Demand for Heating and Cooling
Threshold Source Near-Term (2021-
2050)
Midterm (2035-
2064)
Late-Century (2070-2099)
Low Emissions High Emissions
Building Energy Use
Cooling Degree
Days 66% 77% 80% 89% CEC 2019c
Heating Degree
Days -43% -68% -82% -161% CEC 2019c
Note: NA = not available.
Source: CEC 2019c
As shown in Table 11, in the near-term period, Cooling Degree Days in the City will increase by 66 percent while
Heating Degree Days will decrease by 43 percent compared to historic averages. By the midterm period, Cooling
Degree Days in the City will increase by 77 percent while Heating Degree Days will decrease by 68 percent compared
to historic averages. In the late-century period under the medium emissions scenario, Cooling Degree Days will
increase by 80 percent while Heating Degree Days will decrease by 82 percent . Under a high emissions scenario in
the late-century period, Cooling Degree Days will increase by 89 percent while Heating Degree Day s will decrease by
161 percent.
Changes in Cooling Degree Days will have implications for energy demand in residential and nonresidential buildings
in the City with a higher energy demand for cooling and a decrease in energy demand for heating, in general . In
general, for buildings in the City, increases in Cooling Degree Days will result in increased electricity demand for
cooling and place increased demand on the electricity grid, particularly during extreme heat days and heat wave
events which is projected to increase peak electricity demand for utilities . Currently, during extreme heat days and
heat wave events, electricity utilities and the State’s grid operator, California Independent System Operator, initiate
“Flex Alerts”, requesting customers to conserve energy during certain times of the day to reduce stress on the
electricity grid (KSBY Santa Barbara-San Luis Obispo 2021). Some initial research that models future changes in peak
load for utilities in California during extreme heat events has demonstrated that peak loads are substantially more
sensitive to temperature anomalies, indicating warm-anomalous temperatures (e.g., extreme heat days and heat
waves) will have a disproportionate impact on higher -intensity electricity consumption (Kumar et al. 2020). The
research also indicates that disregarding the asymmetry in temperature response of electricity demand will lead to
underestimating the climate-sensitive portion of the upper extremes of demand for electricity utilities in California, for
short-term (2021-2040) and long-term (2081-2099) time periods included in the study.
As noted above, the urban heat island effect and hotspots in the City are likely to experience disproportionate
increases in ambient air temperature during extreme heat days and heat wave events, further increasing electricity
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for homes without air conditioning. As noted in the City’s recent Housin g Element update, approximately 79 percent
of the City’s housing stock was built before 1989 (City of San Luis Obispo 2020a). These older and, in general, less
energy efficient homes are more susceptible to increases in energy demand for heating and cooling.
Key Findings and Policy Considerations
The Margarita Avenue Neighborhood (Census Tract 111.03) include s population characteristics that make this area
particularly vulnerable to extreme heat and is located in an area of the City with increased urban heat island
severity. Resilience strategies that mitigate impacts of the urban heat island effect should focus on supporting
this area of the City.
Shifts in temperature and extreme heat will result in changes in energy demand for cooling in the City, with
increased demand in areas experiencing more severe urban heat island hotspots. As the City implements it’s
recently adopted Climate Action Plan and as well as the Resilient SLO strategies, solutions that both reduce GHG
emissions and help the City adapt to impacts of climate change should be prioritized.
Older and, in general, less energy efficient homes are more susceptible to increases in energy demand for
heating and cooling. Only 34 percent of homes in San Luis Obispo County have air conditioning with likely similar
percentages in the City, making the City and it’s building stock particularly ill-equipped to projected increases in
heat wave events.
Extreme heat days and heat waves will have a disproportionate impact on electricity demand, with higher
electricity demand projected for these events in the future. These projections place an increased urgency on
electricity utilities to plan for higher electricity demand during these events in future.
EXTREME HEAT AND COMMUNITY RESILIENCE
Heat-Sensitive Populations
As discussed in Section 2.2., over the age of 65, infants and
children, individuals with chronic health conditions (e.g.,
cardiovascular disease, asthma), low-income populations, athletes
training outdoors, and outdoor workers are particularly vulnerable
to climate-related hazards including extreme heat (CDC 2019).
Increased temperatures have been reported to cause heat stroke,
heat exhaustion, heat syncope, and heat cramps, with certain
vulnerable populations at increased probability of experiencing
these effects (Kovats and Hajat 2008). Homeless populations often have higher rates of chronic disease because of
extreme poverty, delays in seeking care, nonadherence to therapy, substance abuse, cognitive impairment, and other
factors, placing them at increased risk during extreme heat events. Additionally, preexisting psychiatric illness can triple
the risk of death for homeless populations during extreme heat events (Ramin and Svoboda 2009). Extreme heat can
also worsen air quality, quickening the production of ozone in areas with increased concentrations of ozone precursors
(i.e., oxides of nitrogen and reactive organic gases) (Knowlton et al. 2004). As shown in Figure 13 there is significant
overlap between areas of moderate to severe urban heat island effect and areas with a higher share of older adults and
youth under 5 years of age. The California Communities Environmental Health Screening Tool (CalEnviroScreen 4.0)
includes an asthma prevalence indicator that measures the rate of emergency department visits for asthma. Although
asthma rates in the City are low compared to statewide levels, there are areas of the City with relatively high asthma
prevalence compared to local levels. Exposure to extreme heat has been shown to increase the risk of hospitalization for
those with asthma (Dahl et al. 2019). As shown in Figure 14, the southern part of the City includes areas of more severe
urban heat island effect and higher asthma prevalence. As noted in Section 2.2.2., the Margarita Avenue Neighborhood
(Census Tract 111.03) and the West of South Higuera neighborhood (Census Tract 115.01) both include population
characteristics that make these areas particularly vulnerable to extreme heat including higher percentages of elderly and
disabled residents in these areas as well 50 percent of residents earning less than 200 percent of the federal poverty
level in the Margarita Avenue Neighborhood. DRAFTPage 278 of 669
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Sources: Data received from SLOCOG in 2021, downloaded from The Trust for Public Lands in 2020, City of San Luis Obispo in 2020,
County of San Luis Obispo in 2020
Figure 13 Youth and Elderly Populations and Urban Heat Island Severity in the City DRAFTPage 279 of 669
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Sources: Data downloaded from OEHHA in 2021, downloaded from The Trust for Public Lands in 2020, City of San Luis Obispo in 2020, County of
San Luis Obispo in 2020 and received from CBEC Engineering in 2020
Figure 14 Asthma Rate Prevalence and Urban Heat Island Severity in the City DRAFTPage 280 of 669
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Public Health and Extreme Heat
For this analysis, the California Heat Assessment Tool (CHAT) was used to identify how Heat Health Events would
increase in the future. A Heat Health Event, for the purposes of the tool, is defined as any event that results in
negative public health impacts, regardless of the absolute temperature. The tool includes unique Heat Health
Events threshold for locations throughout the state, specific to the climat e and the historical sensitivity of people in
that area to past extreme heat events. Heat Health Events are defined by a set of meteorological conditions over
several days that have been associated with significant negative public health impacts (i.e., rat e of visits to local
emergency rooms) in a specific location. The defined temperature threshold for the City in the CHAT tool is days
when maximum temperatures reach 92.6°F and maximum humidity reaches 50.5 percent. Specifically, the tool
focuses on emergency room visits for individuals under four and above 65 as well as all non -white individuals, to
define a vulnerable population cohort. For this analysis, the CHAT tool and the projected increase in Heat Health
Events in the City for the general population s and vulnerable populations, as defined by the tool, are used. For
more information on the tool and methodology used to identify Heat Health Events, please visit the CHAT Tool
website (cal-heat.org). Table 12 includes increases in Heat Health Events for the general population and vulnerable
populations in the City through 2099.
Table 12 Heat Health Events through 2099
Impact Impact Type Population Historic
(1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Threshold Source Low
Emissions
High
Emissions
Building
Energy Use
Heat Health
Events (HHE) General Population NA 1.3 1.4 1.75 5.4 CEC 2018
Heat Health
Events (HHE)
Vulnerable
Populations NA 8.23 10 11.2 12 CEC 2018
Note: NA = not available; CHAT = California Heat Assessment Tool.
Source: CEC 2018
As shown in Table 12, during the near-term period, the City’s general population will experience approximately 1.3
Heat Health Events while vulnerable populations to extreme heat will experience 8.23 H eat Health Events per year
resulting in projected increases in demand for emergency services and hospital room visits. By the midterm period,
the City’s general population will experience approximately 1.4 Heat Health Events per year while vulnerable
populations will experience 10 Heat Health Events per year. In the midterm period under the medium emissions
scenario, the general population will experience approximately 1.75 Heat Health Events per year while vulnerable
populations will experience 11.2 Heat Health Events per year. Under the high emissions scenari o for the late-century
period, the City’s general population will experience a large increase to approximately 5.4 Heat Health Events per
year while vulnerable populations to extreme heat will experience 12 Heat Health Events per year. As shown in Table
12, Heat Health Events for both the general population and vulnerable populations will continue to increase through
the late-century period. For the general population, by the late -century period, Heat Health events will increase
between 33 percent (low emissions scenario) and 315 percent (high emissions scenario). For vulnerable populations at
increased risk from heat-related impacts, by the late-century period, Heat Health events will increase between 3 6
percent (low emissions scenario) and 46 percent (high emissions scenario). This analysis demonstrates a general
increase in Heat Health Events throughout the century with a more pronounced impact on vulnerable populations
who are at increased risk during Heat Health Events.
Environmental Justice and Extreme Heat
Alongside populations with health sensitivities, residents with specific sociodemographic characteristics are at
increased sensitivity to extreme heat events (CDC 2019). Research has found that low -income residents spend a larger
proportion of their income on utilities, including electricity use for cooling, with these residents being
disproportionately affected during extreme heat events (Voelkel et al. 2018). Additionally, research has found that
low-income neighborhoods can often have less tree coverage and park space, further contributing to the DRAFTPage 281 of 669
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disproportionate impact on low-income residents (Zhu and Zhang 2008). Additionally, decreased access to
transportation services can further increase exposure and health risk s from extreme heat events for the unhoused
community (Ramin and Svoboda 2009). Unhoused individuals are also at increased risk from extreme heat events
with, generally, less access to places to cool off and healthcare resources during these events. Figure 15 shows the
location of low-income areas in the City, based on the San Luis Obispo Council of Government’s (SLOCOG) regional
definition of low-income. The map shows urban heat island hotspots and areas where average income level is less
than 80 percent of the region’s average median income. Unhoused individuals are also at increased risk from extreme
heat events with, generally, less access to places to cool off and healthcare resources during these events.
Additionally, decreased access to transportation services can further increase exposure and health risks from extreme
heat events for the unhoused community (Ramin and Svoboda 2009).
The Margarita Avenue Neighborhood (Census Tract 111.03) is an area of the city with a particularly vulnerable
population in regard to extreme heat. This area includes a high percentage of elderly and disabled residents, a high
percentage of residents experiencing linguistic isolation, and 50 percent of residents earning less than 200 percent of
the federal poverty level. This census tract also is located in a portion of the City th at experiences a more intense
severity of the urban heat island effect, resulting in potentially disproportionate impacts on this population during
extreme heat events. The West of South Higuera neighborhood (Census Tract 115.01) also stands out as a particularly
vulnerable to extreme heat, with the area also near urban heat island hotspots and includes a high percentage of
elderly and disabled residents.
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Sources: Data received from SLOCOG in 2021, The Trust for Public Lands in 2020, City of San Luis Obispo in 2020, County of San Luis Obispo in
2020 and received from CBEC Engineering in 2020
Figure 15 Low-Income Areas and Urban Heat Island Severity in the City DRAFTPage 283 of 669
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Economic Systems and Extreme Heat
As discussed previously and shown in Table 9 and 10, the City will experience increases in average annual
temperature and extreme heat days throughout the 21 st century. However, these increases are, in general, less intense
than increases many other parts of California, particularly in southern California and the San Joaquin Valley. Coastal
communities in the County as well as the City already experience an influx of visitors during the summer months,
many of them escaping the more extreme summer heat in t he San Joaquin Valley. This phenomenon was even more
pronounced during the recent heat waves in the summer of 2020, with the County and the City experiencing record
maximum temperatures coupled with an influx of visitors escaping heat in other parts of the state (San Luis Obispo
Tribune 2020). As shown in Figure 16, by approximately 2050, increases in average temperatures will be less severe
relative to other parts of the state.
Increases in average temperature in June through July by 2050 under a high emissions scenario.
Source: Climate Impact Labs 2021
Figure 16 Relative Changes in Extreme Heat by 2050
Due to this milder change in temperature, the City and the County are likely to increasingly be come a refuge for
visitors and future permanent residents looking to escape more extreme climate impacts. This influx could have
secondary impacts on the City including increase demand for services, increases in traffic congestion, and increases
demand for housing, placing additional pressure on the City’s housing market and affordability issues. Given that the
City is an attractive destination for tourism, coupled with the characteristics that could serve as a refuge for the
impacts from climate change, these factors pose a unique issues with potential benefits and drawbacks that should
be considered carefully.
Community Extreme Heat Concerns
As part of the community priority survey, when participants were asked to report on their level of concern for extreme
heat, as shown in Figure 17, 87 percent of respondents indicated that they were “Somewhat” or “Very” concerned about
the issue. Ninety percent of individuals indicated they had been “Somewhat” or “Very” impacted by extreme heat in the
past 1-3 years. Additionally, individuals with a household income of less than $50,000 and individuals between the ages
of 18 and 24 had the highest level of concern for extreme heat. Individuals who note their housing situation as “Renter”
or “Other” indicate the highest level of concern for extreme heat (i.e., 79 percent versus 58 percent for homeowners). DRAFTPage 284 of 669
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Sources: Resilient SLO Community Priorities Survey
Figure 17 City Resident’s Extreme Heat Concern and Impact
Key Findings and Policy Considerations
The Margarita Avenue Neighborhood (Census Tract 111.03) West of South Higuera neighborhood (Census Tract
115.01) is an area of the city with a particularly vulnerable population in regard to extreme heat, with a high
percentage of elderly, disabled, or low-income residents. The West of South Higuera neighborhood (Census
Tract 115.01) also includes a high percentage of elderly and disabled residents, making this area particularly
vulnerable to extreme heat impact.
Low-income residents are particularly vulnerable to extreme heat impacts due to a number of factors including a
higher reliance on public transit (leaving these residents more exposed to extreme heat during transit use), a
higher percentage of income being devoted toward utility bills , and a trend of lower income neighborhoods
having less tree cover. Unhoused individuals are also at increased risk from extreme heat events with, generally,
less access to places to cool off and healthcare resources during these events.
The City and the County, in general, have historically served as a destination for summer tourists to escape more
extreme summer heat in the San Joaquin Valley and southern California. As extreme heat events continue to
increase disproportionately in those areas of the stat e compared to less severe increases locally, the City may
experience increases in this phenomenon placing increased demand on services, impacts on City infrastructure
and resources, as well increased pressure on the housing shortage issue in the City from new permanent
residents.
13%
18%
69%
9%
42%
48%
0%
10%
20%
30%
40%
50%
60%
70%
80%
Not at all Somewhat VeryPercent of RespondentsLevel of Concern
EXTREME HEAT CONCERN & IMPACT
Which of the following climate change impacts are you concerned about [Extreme Heat]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Extreme Heat]?
Total Responses = 328 DRAFTPage 285 of 669
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2.3.3 Adaptive Capacity for Temperature and Extreme Heat Events
ADAPTIVE CAPACITY RATING: LOW
While the City has experienced periods of extreme heat historically, this climate -related hazard has not been a
prominent issue for the City in the past. Because prolonged heat events have been rare in the City, both the City’s
2006 Local Hazard Mitigation Plan and the more recent Annex G of the County’s Multi-Jurisdictional Hazard
Mitigation Plan do not discuss or evaluate extreme heat events in any detail. Specifically, the City’s portion of Annex
G of the County’s Multi-Jurisdictional Hazard Mitigation Plan does not include any mitigation actions specific to
extreme heat or protecting vulnerable populations from extreme heat. The City’s Emergency Operation Plan also
does not include a specific discussion or protocols for addressing extreme heat events when they occur. The
exclusion of extreme heat from these documents is likely because these even ts have not been an issue historically.
The City is currently working to implement its recently adopted Climate Action Plan which includes strategies for the
electrification of new and existing buildings (Green Buildings 1.1 and 1.2 in City’s C limate Action Plan). As the City
continues this work to electrify new and existing buildings, changes in electricity demand for cooling will remain an
important consideration for the energy desig n of new buildings and existing building retrofits. Decreases in HDDs
due increase in annual maximum and minimum temperatures
as shown in Table 11, will result in decreased demand for
heating fuels, which for buildings in the City is primarily
natural gas. Decreases in energy demand for heating also
has the potential to decrease the City’s overall GHG
emissions and help achieve the City’s GHG emissions
reduction targets.
As noted previously, 79 percent of the City’s housing stock
was built before 1989, reducing the ability of these older and
less energy efficient homes to adapt to changes in extreme
heat. In the County as a whole which can serve as proxy for
the City, only 34 percent of households include air
conditioning, placing these households at increa sed risk
when extreme heat events do occur (CEC 2009). Retrofitting
homes with central air conditioning o r air conditioning units
can be a major expense, especially for low-income
households, and may not be possible for City residents who
are renting. Overall, because the City has not historically
experienced many extreme heat conditions,, residents are not
acclimatized to or prepared for extreme heat conditions,
which makes the City particularly sensitive to extreme
temperatures.
For these reasons, the adaptive capacity ranking for increased temperature s and extreme heat is ranked as low.
Climate Action Plan and Resilient SLO
In 2020, the City adopt the Climate Action
Plan for Community Recovery which
establishes a community-wide goal of carbon
neutrality by 2035, adopts sector specific
goals, and provides foundational actions to
establish a trajectory towards achieving those
goals. The Resilient SLO project focuses on
developing strategies to make the City more
resilient to the impacts of climate change.
However, as the City implements the Climate
Action Plan and the Resilient SLO strategies,
it will be important to prioritize solutions that
both reduce GHG emissions and help the
City adapt to impacts of climate change.
Both reducing emissions and adapting to
climate change serve to create a more
resilient community. DRAFTPage 286 of 669
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2.3.4 Vulnerability Summary
Overall, the City is projected to experience noticeable increases in annual average temperatures and extreme heat
events. These changes will result in varyin g impacts on the City and its residents as discussed above. Based on the
analysis of various impacts discussed in Section 3.2.2, the City’s potential impact scoring is Medium (2). Impacts that
are unique to the City and should be given increased consideration during the adaptation strategy development
process are discussed below.
Natural System Findings
Changes in temperature and extreme heat are likely to have negative impacts on the City’s tree canopy with
some tree species no longer suitable for future minimum and maximum temperatures. Any future policies
focused on improving the City’s tree canopy or green spaces to m itigate the urban heat island effect should
carefully consider what plant and tree species will be suitable for future climate conditions.
Climate change is projected in invasive species in the City’s open spaces, affecting coastal sage scrub habitats as
well as the City’s oak species from Sudden Oak Death.
Regional impacts on the agriculture and viticulture industries from shifting temperatures have the potential to
impact the City via decreases in wine and vineyard-based tourism, with the City relying heavily on revenue and
employment opportunities in these industries. Resilience strategies focused on economic impacts should
consider potential impacts on viticulture vineyard -based tourism and potential diversification of the City’s tax
revenue sources and employment industries.
Built Environment Findings
The Margarita Avenue Neighborhood (Census Tract 111.03) include s population characteristics that make this area
particularly vulnerable to extreme heat and is located in an area of the City with increased urban heat island
severity. Resilience strategies that mitigate impacts of the urban heat island effect should focus on supporting
this area of the City.
Shifts in temperature and extreme heat will result in changes in energy demand for cooling in the City, with
increased demand in areas experiencing more severe urban heat island hotspots. As the City implements it’s
recently adopted Climate Action Plan and as well as the Resilient SLO strategies, soluti ons that both reduce GHG
emissions and help the City adapt to impacts of climate change should be prioritized.
The City’s historically moderate climate has, in general, not required the City’s existing building stock to be
designed or equipped with air conditioning. However, as average temperatures and extreme heat events increase
in the future, residents are ill-equipped to prepare for these events. Additionally, increases in temperature and
extreme heat will result in increased energy demand for cooling, which underscores the need to support
distributed energy resources, customer sited energy storage, demand response, and grid/building connected
appliances and vehicles.
Extreme heat days and heat waves will have a disproportionate impact on electricity demand, with higher
electricity demand projected for these events in the future. These projections place an increased urgency on
electricity utilities to plan for higher electricity demand during these events in future.
Community Resilience Findings
The Margarita Avenue Neighborhood (Census Tract 111.03) West of South Higuera neighborhood (Census Tract
115.01) is an area of the city with a particularly vulnerable population in regard to extreme heat, with a high
percentage of elderly, disabled, or low -income residents. The West of South Higuera neighborhood (Census
Tract 115.01) also includes a high percentage of elderly and disabled residents, making this area particularly
vulnerable to extreme heat impact.
Low-income residents are particularly vulnerable to extreme heat impacts due to a number of factors including a
higher reliance on public transit (leaving these residents more exposed to extreme heat during transit use), a
higher percentage of income being devoted toward utility bills, and a trend of lowe r income neighborhoods DRAFTPage 287 of 669
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having less tree cover. Unhoused individuals are also at increased risk from extreme heat events with, generally,
less access to places to cool off and healthcare resources during these events.
The City and the County, in general, have historically served as a destination for summer tourists to escape more
extreme summer heat in the San Joaquin Valley and southern California. As extreme heat events continue to
increase disproportionately in those areas of the state compared to less severe increases locally, the City may
experience increases in this phenomenon placing increased demand on services, impacts on City infrastructure and
resources, as well increased pressure on the housing shortage issue in the City from new permanent residents.
Temperatures and Extreme Heat Vulnerability Score
Adaptive Capacity: Low (3)
Potential Impact: Medium (2)
Vulnerability Score: 4
2.4 LONG-TERM DROUGHT ANALYSIS
This section discusses future long-term drought scenarios for the City and analyzes how long-term drought could
impact City and its population as well as highlighting what capacity the City and partner agencies already have in
place to address future drought impacts.
2.4.1 Future Exposure to Long-Term Drought Scenarios
Long-term drought can have environmental, agricultural, health, economic, and social consequences. The County,
along with larger areas of California, experiences periods of long -term drought that stress ecosystems and water
supplies; and subsequently, impact agriculture, public healt h, and the economy. The City relies on regional water
supplies with the four primary sources being Whale Rock Reservoir, Salinas Reservoir, Nacimiento Reservoir, and
recycled water (City of San Luis Obispo 2019). Because the City relies on reservoirs in the County, outside the City
limits, this analysis focuses on long-term drought scenario projections for the County as a whole.
While average annual precipitation in the County is projected to trend upward in future years, the key finding for this
climate effect is that precipitation patterns are expected to become more volatile, with potentially less frequent but
intense storms that produce above average amounts of precipitation. As discussed in more detail in Section 2.5,
precipitation patterns in California oscillate between extremely dry and wet periods . Climate change is anticipated to
exacerbate these seasonal extremes with dry periods becoming dryer and wet periods becoming w etter (OPR et al.
2018b:19). As a result, the frequency and severity of large storm events are anticipated to increase as well. These
oscillations between extremely dry and extremely wet periods, which have occurred historically in the state, are
anticipated to become more severe with rapid shifts from dry to wet periods known as “whiplash events” (Swain et al.
2016). With the increased severity of oscillation between wet and dry periods and precipitation occurring over more
intense but shorter periods in the year, this will reduce opportunities for groundwater recharge which ideally occurs
during prolonged wet periods allowing for soil infiltration, deeper percolation, and the resulting groundwater
recharge. As discussed further in Section 2.4.2, while a unique long-term drought scenario would likely affect the
City’s overall water supply management practices, there is the potential for there still to be above average wet years
within a long-term drought, as shown in Figure 18. These above average wet years have the potential to replenish
water supplies in the City’s reservoirs and help mitigate the impacts of long -term drought. Table 13 includes
projections for average annual precipitation in the County through 2099 as well as rainfall projections for change s in
the 5-year storm event, demonstrating the increased intensity of large storm events and wet years in the future.
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Table 13 Changes in Average Annual Precipitation and 5-Year Storm Event in San Luis Obispo County
Average Annual Precipitation Historic Average Annual
Precipitation (1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Medium
Emissions
High Emissions
Average Annual Precipitation (inches) 16.1 18.1 17.8 17.2 19.8
5-Year Storm Event (2-day rainfall) 7.9 7.9 8 8.2 9.8
Source: CEC 2019a
As shown in Table 13 above, under both the low and high emissions scenarios, the County is expected to experience
slight overall increases in average annual precipitation in the late century. However, projections show the County will
experience increased variability and volatility in precipitation events such as droughts. The County and state have a
highly variable climate that is susceptible to prolonged periods of drought, and recent research suggests that extended
drought occurrence (a “mega-drought”) could become more pervasive in future decades (OPR et al. 2018b).
Cal-Adapt uses data to model an extended drought scenario for all of California from 2051 to 2070 specifically using
the HadGEM2-ES GCM model under a high emissions scenario. The extended drought scenario is based on the
average annual precipitation over 20 years. As shown in Table 13, the County’s observed historical (1961-1990)
average annual rainfall accumulation is 16.1 inches. Under the anticipated drought scenario between 2051 and 2070,
the County’s average annual rainfall accumulation would decrease to 13.3 inches (CEC 2019a), resulting in an
approximately 18 percent decrease in annual average rainfall over a 20 -year period.
Source: Cal-Adapt 2021
Figure 18 Projected Drought Conditions between 2051 and 2070 for San Luis Obispo County DRAFTPage 289 of 669
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2.4.2 Drought Sensitivities and Impacts
This section discusses the City’s existing sensitivities to long-term drought and analyzes potential effects on the City,
discussed in the three general impact categories (e.g., Natural Systems, Built Environment, Community Resilience).
DROUGHT AND NATURAL SYSTEMS
Open Space and Ecosystem Functions
The City’s designated open space areas include a mixture of
vegetation types including oak woodland, grassland, coastal
sage scrub, and chaparral that are anticipated to be impacted
by changes in annual average temperatures, extreme heat, and
long-term droughts (OPR et al. 2018b). Historically, the
duration and intensity of droughts in California varies
substantially with elevation, latitude, distance to coast, and
local soil characteristics. Native perennial grasses tend to
concentrate growth periods during wet winter months, ada pting to the annual summer drought (Vaughn et al.
2011). Some native perennial grasses can survive prolonged droughts in a non -green state and then regenerate
after it rains (Potter 2015). As a result, it is projected that most grassland species should be adaptive to tolerate
climate extremes and variability (OPR et al. 2018b). The diversity of ecological communities along the California
coast are linked to the summer marine layer of fog and low clouds, allow for adaptations. Chaparral shrubs, in
general are more drought tolerant. F uture changes in precipitation and drought will impact grasslands and
wildflowers on the Central Coast and will be dependent on the proximity to the coast as well as the relative
proportion of native to non-native, and perennial to annual species (OPR et al. 2018b).
In dryer years and drought periods, demographic rates for annual plants (e.g., survival, reproduction) are lower than
in wetter years (Fox et al. 2006). As dry years and long-term droughts become more common in the future,
population growth rates of annual plant species will become marginal, and populations are likely to become locally
extinct. Foraging on these annuals, particularly by deer, rabbits, and woodrats reduces population growth even more
than drought in some species, but not others (OPR et al. 2018b).
Deer browse (e.g., leaves, twigs, and buds of woody plants eaten by deer) reduces growth, reproduction, and survival
in ceanothus (e.g., California Lilac). As the abundances of deer and other wildlife declined during the recent drought
of 2011-2017, previously browsed shrubs grew and reproduced well and then resp onded rapidly to the two wet years
since. These observations suggest that unless deer populations increase again between droughts, or in areas without
much deer browse, ceanothus shrub are likely to grow rapidly, but will become vulnerable with further dro ughts
projected under climate change (OPR et al. 2018b).
Key Findings and Policy Considerations
The City’s designated open space areas include a mixture of vegetation types including oak woodland, grassland,
coastal sage scrub, and chaparral that are anticipated to be impacted by changes in annual average
temperatures, extreme heat, and long -term droughts (OPR et al. 2018b).
As dry years and long-term droughts become more common in the future, population growth rates of annual
plant species will become marginal, and populations are likely to become locally extinct (OPR et al. 2018b). DRAFTPage 290 of 669
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DROUGHT AND THE BUILT ENVIRONMENT
Water Supply
While increasingly frequent and prolonged droughts affect the
City’s drinking water supply, the City’s built environment (e.g.,
buildings, roadways) will not experience direct physical impacts
associated with this climate-related hazard. However, drought
conditions and other climate-related effects will likely effect
reservoirs, located outside the City boundaries, which provide
water to the City. For the Central Coast, a 50-year projection for
land uses from 2012 to 2062 suggest potential changes that could
affect groundwater supplies including a large amount of grassland habitat loss over 50 years that wil l exacerbate
challenges in preserving and recharging groundwater aquifers , as well as increased water demand due to
urbanization and expansion of berries and vineyards (Wilson et al. 2016).
As shown in Figure 18, even during a future long-term drought scenario, there would be years with above average
rainfall for one or even multi-year periods. However, these one or multi -year periods with above average rainfall may
not be sufficient to restore reservoirs to normal water levels compared to non -drought periods. For example, during
the statewide drought between approximately 2011 and 2016, water supplies on the Central Coast were severely
affected with increases in reservoirs and groundwater levels varying significantly across the Central Coast region
following the above average 2016-2017 winter rain season (OPR et al. 2018b). As noted in the City’s 2017 Water
Resources Status Report, between January 2017 and June 2017 the water supply in the Salinas Reservoir went from 10
percent to 100 percent, the Whale Rock Reservoir went from 32 percent to 79, and the Nacimiento Reservoir shifted
from 25 percent to 78 percent (City of San Luis Obispo 2021b). This dramatic shift from a multi -year drought between
2011 and 2015 drought followed by an above average wet year in the 2016-2017 winter rain season was characteristic
of a whiplash event (Swain et al. 2018) and allowed the City to replenish its water suppl ies. However, these whiplash
events may affect water supply management practices over the long -term, particularly as the swings from multi-year
dry to wet periods become more prolonged and more severe (Persad et al. 2020).
As part of the City’s 2020 Urban Water Management Plans (UWMP), climate change modeling was conducted to
determine future projections on the City’s safe annual yield. Safe annual yield is generally defined as a measurement
used to determine the average replenishment rate of a water body or aquifer from natural and artificial recharge, which
factors in evaporation, transpiration, and basin outflow into the replenishment rates. Safe annual yields are calculated as
the quantity of water which can be withdrawn regularly and permanently without dangerous depletion of the storage
reserve. Based on the climate modeling included in the 2020 UWMP, it was determined that, when accounting for future
precipitation patterns due to climate change, the safe annual yield for Whale Rock and Salinas Reservoirs (two reservoirs
included in the City’s water supply portfolio) could shift from a decrease of as much as 850-acre-feet per year (AFY) to
an increase of as much as 160 AFY. However, these potential shifts are relatively small compared to the City’s overall safe
annual yield of 10,130 acre-feet from the full water supply portfolio, with shifts from climate change accounting for an
approximately 8 percent decrease to 2 percent increase in the City’s overall supply (City of San Luis Obispo 2021b).
Sediment Deposition
The buildup of sedimentation in reservoirs can reduce a reservoir’s available storage volume. As noted in the City’s 2020
Urban Water Management Plan (UWMP), the Whale Rock and Salinas Reservoirs, which provide water to City, are
projected to experience an total loss of 500 acre-feet of water between 2010 to 2060 period (a rate of 10 acre-feet per year
over 50 years). Intense, long-duration winter storm rainfall can result in the movement of large sediment quantities into
reservoirs (OPR et al. 2018b). In the Central Coast region, annual sediment movement from individual watersheds varies by
a factor of 500 or more between extreme dry and extreme wet years (Conaway et al., 2013; East et al., 2018). Landscape
disturbances including wildfire, post-wildfire runoff, or landslides after wet winters, is projected to increase sediment yield
from watersheds along the Central Coast (OPR et al. 2018b) and will reduce the amount of water-storage capacity in
dammed Central Coast reservoirs (Smith et al. 2018). Changes in vegetation and fire regimes could also potentially add to
the likelihood of increased sediment flux (Sankey et al., 2017). Sediment, including the nutrients and chemicals adsorbed in
sediment, can result in decreased water quality and make water treatment more technically complex and more costly. DRAFTPage 291 of 669
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Key Findings and Policy Considerations
Dramatic shifts from multi-year dry periods to wet periods, similar to the 2011-2015 drought followed by an above
average wet year in the 2016-2017, are known as whiplash events (Swain et al. 2018) and they are expected to
become more severe in the future. These whiplash events may affect water supply management practices over the
long-term, particularly as the swings from multi-year dry to wet periods become more prolonged and more severe,
with an emphasis on increasing rainfall storage when it does occur during the wet periods (Persad et al. 2020).
Buildup of sedimentation that reduces a reservoir’s available volume already occurs in the City’s water storage
system, with the City implementing programs and policies to address this storage loss over the long term. However,
landscape disturbances including wildfire, post-wildfire runoff, or landslides after wet winters, is projected to
increase sediment yield from watersheds along the Central Coast (OPR et al. 2018b), with the potential to further
reduce the amount of water-storage capacity in dammed Central Coast reservoirs (Smith et al. 2018).
The City’s Safe Annual Yield analysis included in the 2020 UWMP modeled potential impacts on the City’s water
supplying, finding that changes in precipitation could result in a decrease of as much as 850 AFY to an increase
of as much as 160 AFY, accounting for an approximately 8 percent decrease to 2 percent increase in the City’s
overall water supply (City of San Luis Obispo 2021b).
DROUGHT AND COMMUNITY RESILIENCE
Vector-borne and Infectious Disease
Increases in temperature and extreme heat events are
associated with increases in vector-borne and infectious
disease transmission (OPR et a. 2018b). Based on recent
research, summarized in the Central Coast Report, future long-
term drought scenarios have the potential to increase the
prevalence of certain vector-borne diseases present on in the
central coast region. For example, long-term drought can affect
the life cycles and extend the habitat range of native tick
species that can harbor Lyme disease and other illnesses (OPR et a. 2018b ). Cases of vector-borne disease,
including Lyme disease, are projected to increase in the future due to climate change (Estrada -Pena, A., N. Ayllon,
and J. de la Fuente 2012). However, in the Central Coast region, the spread of Lyme disease has likely been
contained due to the area’s drier climate a nd differing vegetation (MacDonald, A.J. et al. 2017). A newly identified
vector-borne disease, Pacific Coast tick fever (PCTP), has been identified (Padgett, K.A., et al. 2016). Although an
emerging illness, a few of the human cases originated specifically in the Central Coast. PCTP has exhibited a
summer trend so far. Therefore, increasing temperatures have the potential to extend PCTP’s transmittal season in
the Central Coast.
A lack of soil moisture during long-term droughts can increase dust particle concentration, which can include harmful
fungal spores and viruses, including coccidioidomycosis (valley fever) (OPR et a. 2018b). The California Department of
Public Health (CDHP) has highlighted the Central Coast as a high-risk area for valley fever (OPR et a. 2018b). Valley
fever is found in disturbed, dry soil particles that must be inhaled. Symptoms of Valley fever include chest pain,
exhaustion, fever, coughing, joint and muscle pain, and difficulty breathing. Certain populations including pregnant
women, the elderly, African, and Filipino Americans are particularly vulnerable to the severe cases of the disease
(Brown et al. 2013). Santa Barbara and San Luis Obispo Counties, where the Valley fever fungus, C. immitis, is
endemic, reported larger numbers of cases in 2017, with the CDPH reporting over 500 cases for these two counties
(San Luis Obispo Tribune 2016).
Key Findings and Policy Considerations
Increases in temperature and extreme heat ev ents are associated with increases in vector-borne and infectious
disease transmission, with future long-term drought scenarios potentially increasing the prevalence of certain
vector-borne diseases present on in the central coast region including Lyme disease and Valley fever. DRAFTPage 292 of 669
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2.4.3 Adaptive Capacity for Drought Impacts
ADAPTIVE CAPACITY RATING: HIGH
Utilities Department and Water Management
Short- and long-term droughts have historically been an issue for the City and the Central Coast region. As a result,
the City already has a comprehensive set of initiatives and resources in place to address drought periods when they
do occur. In 2021, the City adopted the 2020 UWMP which evaluates the current and projected water supplies
through the year 2040. The UWMP was prepared in accordance with the Urban Water Management Planning Act,
and accordingly, will be updated every 5 years and submitted to the Cali fornia Department of Water Resources. Goals
in the UWMP related to this this Report include the following:
assess current and future water use trends in the community;
summarize the water supply and the water system;
assess water supply reliability;
document the water demand; and
manage measures in place to balance supply and demand .
The 2020 UWMP includes a section specially on Water Resiliency Planning which highlights a set of strategies the
City has taken to ensure long -term water resiliency and to mitigate the impacts from a long -term drought
scenario . These include:
a multi-source water supply;
conservative water supply projections;
water use efficiency;
water recycling; and
future groundwater recharge.
As noted in the 2020 UWMP, the City has a Reliability Reserve and a Secondary Water Supply which ha ve been
incorporated in water management planning and calculations to provide a buffer for future unforeseen or
unpredictable long-term impacts to the City’s available water resources such as loss of yield from an existing water
supply source and impacts due to climate change. The Reliability Reserve provides a twenty percent buffer beyond
the City’s projected water demand at build out. As discussed in Section 2.4.2, the 2020 UWMP includes forecasted
projections on the City’s safe annual yield which accounts for potential shifts in precipitation caused by climate
change. The 2020 UWMP also includes key considerations on how climate change may affect water deman d in years
with less rainfall (City of San Luis Obispo 2021b).
In 2006, the City completed the Water Reuse Project, creating the first new source of water for the City since 1961.
The project included improvements to the City’s Water Resource Recovery Facility and an initial eight miles of
distribution pipeline for use by City residents and businesses for landscape irrigation and other approved uses. In
2017, the City completed the Recycled Water Master Plan. The plan describes future opportuni ties for the City to
consider potable reuse, presents a plan to serve recycled water to developing areas of the community for use as
landscape irrigation, prioritizes opportunities to retrofit existing sites to offset potable water use, and explores use of
recycled water outside the City limits during periods where much of the City’s recycled water supply goes
underutilized. Chapter 7 of the plan includes a capital improvement plan for future expansion of the City’s recycled
water distribution system, which is consistent with the City’s larger water supply management strategy to maintain
multi-source water supply. The City’s current recycled water program can generate over 1,000 acre-feet of recycled
water for approved uses, reducing water demand from the Ci ty’s other water supply sources. In 2020, 245 acre -feet
of recycled water were delivered to the community (City of San Luis Obispo 2021b ). DRAFTPage 293 of 669
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As part of the 2020 UWMP, the City has also developed the 2020 Water Shortage Contingency Plan, which
establishes the foundation for a staged response to worsening water shortage conditions that could occur due to
drought, earthquake, infrastructure failure, or other emergenc ies. The 2020 Water Shortage Contingency Plan
establishes the City’s water supplies for a normal year, single dry year (2013) and a multiple dry year scenario,
identified as the years 2011 to 2015, with combined rainfall total for those five years being the lowest on record.
Alongside developing a water shortage assessment, the plan also includes a comprehensive water shortage response
to temporarily augment supply and/or reduce water demand. This response would include voluntary reduction
measures, mandatory reduction measures, water use prohibitions, and supplemental water supply options.
General Plan Water and Wastewater Management Element
The City’s General Plan Water and Wastewater Management Element, most recently updated in 2020, includes a
comprehensive set of goals, policies, and programs manage the City’s water supply and includes measures to address
the potential impacts of climate change on the City’s water supply . The updated Water and Wastewater Management
Element coincides with the City’s efforts to incorporate climate change projections into the City’s safe annual yield
assessment and water management practices. Goals in the element focus on the various components of successful
water management including managing the City’s multi -source water supply, water supply accounting and water
demand projections, water conservation practices, and the implementing the City’s recycled water program. The
Water and Wastewater Element also includes a goal specifically for siltation management in the City’s reservoirs,
noting the potential for the increasing intensity of rainfall events as well as post-wildfire runoff to increase siltation
rates and reduce the overall storage capacity of the City’s reservoirs. Noting this potential threat, the Siltation portion
of the element includes a set of policies and programs to proactively implement best management practices to
reduce erosion and subsequent siltation consistent with other City watershed management goals.
Sustainable Groundwater Management Act and Groundwater Recharge
The City, in coordination with the County and partner agencies, are increasing efforts to achieve sustainable
groundwater management through requirements in the Sustainable Groundwater Management Act. The City and
County, in coordination with local water purveyors including the Edna Valley Growers Mutual Company, Edna Ranch
Mutual Water Company, Varian Ranch Mutual Water Company and Golden State Water Company, developed a
Groundwater Sustainability Plan to sustainably manage groundwater resources in the San Luis Obispo Valley
Groundwater Basin and prevent an unreasonable reduction of groundwater storage in the basin. The City’s portion of
the San Luis Valley Groundwater Basin is currently estimated to have a 700 acre -foot per year surplus of groundwater.
This is largely because the City is not currently pumping groundwater. The City plans to resume groundwater
pumping within the next five years to better balance surface water and groundwater use in order to mitigate climate
change impacts.
Alongside development and implementation of the Groundwater Sustainability Plan, through implementation of the
State mandated NPDES Stormwater Program and the Post Construction Requirements , new and re-developments are
required to retain and infiltrate water that would have previously been piped off the property. This requirement helps
to mitigate stormwater runoff and supports groundwater recharge in the San Luis Valley Groundwater Basin.
For these reasons, the adaptive capacity ranking for increased long-term drought is high.
2.4.4 Vulnerability Summary
Due to increases in annual average temperatures and extreme heat discussed in Section 3.2, as well as the increased
likelihood of a long-term drought scenario, the City is vulnerable to impacts from drought caused by climate change.
These changes will result in varying impacts on the City and its residents as discussed above . Based on the analysis of
various impacts discussed in Section 3.3.2, the City’s potential impact scoring is High (3). Impacts that are unique to
the City and should be given increased consideration during the adaptation strategy development process are
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Natural System Findings
The City’s designated open space areas include a mixture of vegetation types in cluding oak woodland, grassland,
coastal sage scrub, and chaparral that are anticipated to be impacted by changes in annual average
temperatures, extreme heat, and long -term droughts (OPR et al. 2018b).
As dry years and long-term droughts become more common in the future, population growth rates of annual
plant species will become marginal, and populations are likely to become locally extinct .
Built Environment Findings
Dramatic shifts from multi-year dry periods to wet periods, similar to the 2011-2015 drought followed by an above
average wet year in the 2016-2017, are known as whiplash events (Swain et al. 2018) and they are expected to
become more severe in the future. These whiplash events may affect water supply management practices over the
long-term, particularly as the swings from multi-year dry to wet periods become more prolonged and more severe,
with an emphasis on increasing rainfall storage when it does occur during the wet periods (Persad et al. 2020).
Buildup of sedimentation that reduces a reservoir’s available volume already occurs in the City’s water storage
system, with the City implementing programs and policies to address this storage loss over the long term. However,
landscape disturbances including wildfire, post-wildfire runoff, or landslides after wet winters, are projected to
increase sediment yield from watersheds along the Central Coast (OPR et al. 2018b), with the potential to further
reduce the amount of water-storage capacity in dammed Central Coast reservoirs (Smith et al. 2018).
The City’s 2020 UWMP modeled potential impacts on the City’s water supplying, finding that changes in
precipitation could result in a decrease of as much as 850 AFY to an increase of as much as 160 AFY, accounting
for an approximately 8 percent decrease to 2 percent increase in the City’s overall water supply (City of San Luis
Obispo 2021b).
With more rapid shifts from dry to wet periods known as “whiplash events ,” precipitation will occur over shorter
more intense periods. This shift has the potential to reduce groundwater recharge which ideally occurs during
prolonged wet periods to allow for soil infiltration, deeper percolation, and more effective groundwater recharge.
However, increases in the intensity of rainfall events, when they do occur in the wet periods, provides an
opportunity to offset potential losses in storage during periods of drought.
The 2020 UWMP includes a section specially on Water Resiliency Planning which highlights a set of strategies the
City has taken to ensure long-term water resiliency and mitigate the imp acts from a long-term drought scenario.
These strategies include a multi -source water supply; conservative water demand projections; water use
efficiency; water recycling; and future ground water recharge.
Community Resilience Findings
Increases in temperature and extreme heat events are associated with increases in vector -borne and infectious
disease transmission, with future long-term drought scenarios potentially increasing the prevalence of certain
vector-borne diseases present on in the central coast region including Lyme disease and valley fever.
Long-Term Drought Vulnerability Score
Adaptive Capacity: High (1.5)
Potential Impact: High (3)
Vulnerability Score: 3.5
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2.5 WILDFIRE ANALYSIS
This section discusses future changes in wildfire in the County and areas surrounding the City and analyzes how these
changes are likely to impact City and its population as well as highlighting what capacity the City and partner
agencies already have in place to address these future impacts.
2.5.1 Future Exposure to Wildfire Risk
Wildfire risk is determined by several factors, such as wind speeds, drought conditions, available wildfire fuel (i.e.,
vegetation), past wildfire suppression activity, and expanding wildland -urban interface (WUI) in and around forests,
grasslands, shrub lands, and other natural areas (Westerling 2018). Climate change effects, including increased
temperatures and changes to precipitation patterns, will exacerbate many of the factors that contribute to wildfire
risk. Recent research has found that increases in global temperatures may be affecting wind patterns and increasing
global wind speeds, however these changes w ould not be experienced uniformly across geographies in the future
(Chen 2020). While the impact of climate change on wind speeds is still uncertain, it is important to recognize this
potential effect and how it may also contribute to wildfire risk in the future.
Increased variability in precipitation may lead to wetter winters and increased vegetative growth in the spring, and
longer and hotter summer periods will lead to the drying of vegetative growth and ultimately result in a greater
amount of readily burned fuel for fires. This has already been seen across the state in recent years, with the area
burned by wildfires increasing in parallel with rising air temperatures (OEHHA 2018). These factors, combined with the
increasing frequency and severity of intense wind conditions, will cause fires to spread rapidly and irregularly, making
it difficult to predict fires’ paths and effec tively deploy fire suppression forces. Pacific Gas and Electric (PG&E) also has
several electrical transmission lines running through the City, which carry significant potential fire risk.
Relative humidity is also an important fire -related weather factor; as humidity levels drop, the dry air causes
vegetation moisture levels to decrease, which consequently increases the likelihood that plant material will ignite and
burn. With an increase in hotter and drier landscapes, humidity levels may continue to drop and result in higher fuel
levels, increasing the risk of wildfire (Schwartz et al., 2015).
Environmental and climatic conditions in and around the City influence the frequency and magnitude of wildfires. The
City often experiences high-wind events, such as the Santa Lucia winds, which originate inland and flow westward
during the late summer and early fall, counter to the prevailing westerly winds that occur throughout much of the
year. Santa Lucia winds contain little humidity, and summers in the City are hot and dry, with precipitation primarily
occurring in the winter months. Thus, the combina tion of the relatively hot, dry Santa Lucia winds occurring at a time
when vegetation in the County and the City is particularly dry following the summer months can contribute to the
ignition and spread of wildfires. Periods of low relative humidity, when dead trees and vegetation cannot absorb
moisture from the air, can also increase the risk of wildfires (City of San Luis Obispo 2011).
The risk of wildfires and subsequent impacts to property and life is greatest at the WUI, which is where urban
development borders wildland fuels. Wildfire risk is compounded in areas of the WUI that are also located in or near
High or Very High Fire Hazard Severity Zones (VHFHSZ). Figure 19 includes CAL FIRE designated Fire Hazard Severity
Zones in and surrounding the City. Portions of southwestern (near the Irish Hills Natural Reserve) and northeastern
(near Reservoir Canyon Natural Reserve) parts of the City are located in or near a VHFHSZ, and many of these
portions of the City overlap with the WUI. Beyond these areas of the City, the risk of urban fires decreases, with most
of the areas surrounding and some locations within the City designated as Moderate Fire Hazard Severity Zone.
Given the City’s urban setting, with minor portions of the City in the VHFHSZ, the analysis for future wildfire risk
incorporates County-level changes in wildfire risk to assess how larger regional risks and potential impacts may affect
the City. Using a statistical model based on historical climate vegetation, population density, and large fire history,
Cal-Adapt provides projections for future annual mean hectares burned within the County when wildfires do occur.
Cal-Adapt does not account for current or planned wildfire management projects. Table 14 and Figure 20 shows the
projected change in average annual area burned within the County under low and high emissions DRAFTPage 296 of 669
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Source: San Luis Obispo County 2019a
Figure 19 Wildfire Hazard Severity Zones In and Near the C ity of San Luis Obispo with Critical Facilities DRAFTPage 297 of 669
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and downloaded from Cal-Adapt in 2021
Figure 20 Change in Average Annual Maximum Temperature in San Luis Obispo County through 2099 DRAFTPage 298 of 669
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scenarios for the central population growth scenario at midterm and late-century timescales. The total area burned
annually by wildfire within the County is expected to rise 15 percent from the historic (1961-1990) annual average of
9,248 hectares to 10,723 hectares in the near-term and increase in the midterm to 10,728 hectares burned annually. In
the late-century, average annual area burned in the County is projected to increase to 10,728 hectares and decrease
slightly to 9,867 hectares under the low and high emissions scenarios, respectively (CEC 20 19d). This reduction in
annual average hectares burned in the late -century period is noted in the research conducted to develop the Cal -
Adapt wildfire tool. As vegetation type and fuel amount, structure, and continuity change in the future due to altered
disturbance regimes (e.g., changes in the frequency, seasonality, duration, extent and severity of wildfire and
infestations by beetles and other pathogens) and climate, f uture wildfire activity and its response to climatic variability
may reduce wildfire activity in some ecosystems (Westerling 2018).
Importantly, Figure 20 illustrates that anticipated changes in wildfire impacts are not homogenous across the County;
for instance, the Santa Lucia Wilderness and the La Panza Mountain range located in the southern central portions of
the County are projected to experience the largest increases in average area burned over the 21st century under both
emissions scenarios. While these areas are outside of the City boundaries and jurisdiction, due to the regional
characteristics of wildfire impacts, wildfire events in these areas could affect the City through secondary impacts such
as short-term and long-term wildfire evacuees, wildfire smoke, and impacts on the County’s regional transportation
network.
Table 14 Changes in Annual Average Area Burned in San Luis Obispo County
Average Annual Area Burned
Historic Modeled1
Average Annual Area
Burned
(1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Medium
Emissions High Emissions
Average Annual Area Burned
(hectares) 9,248 10,723 10,728 10,728 9,867
Notes: RCP = Representative Concentration Pathway.
1 Observed historical average annual area burned data were not available from Cal-Adapt; the modeled historical average annual area burned
data under the medium emissions scenario was available and used as proxy data.
Source: CEC 2019d.
2.5.2 Wildfire Sensitivities and Impact
This section discusses the City’s existing sensitivities to wildfire impacts and analyzes future wildfire risk in the City,
discussed in the three general impact categories (e.g., Natural Systems, Built Environment, Community Resili ence).
WILDFIRE AND NATURAL SYSTEMS
Open Space and Ecosystem Functions
Changes in climate variables including increased average
annual temperatures, annual climatic water deficit, and
relative humidity are all strong predictors of fire occurrence
and burned area in semi-arid regions. These changes in
climate variables are projected to increase wildfire risk in
open spaces and wooded areas in and surrounding the City.
As noted in the Central Coast Region Report, the size of
wildfires in the Central Coast region increases with both air
temperature in the month of ignition and with lower rates of
precipitation in the 12 months preceding the fire, which
create conditions in the natural landscape that increase
wildfire risk (Potter 2017). DRAFTPage 299 of 669
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Chaparral habitat, which is present in the City’s designated open spaces and surrounding areas, is a fire-dependent
evergreen shrubland vegetation community. Human ignitions, fire suppression, and short-term meteorological events
have dominated variability in fire activity in chaparral zones in recent decades (Abatzoglou et al. 2016, Mann et al.
2016). Some research has shown that the increasing frequency of fire on these landscapes have caused coastal sage
shrubs and chaparral to shift to grasses, including e xotic grasses (OPR et al. 2018b). Some research has suggested
that annual and some perennial grasses have the strongest effects on fire regimes and act as ecosystem transformers.
Noting that in many ecosystems, the dense growth habit and flammable tissue o f invasive grasses create continuous
drier fuels that are not present in areas not invaded by non-native grasses (Linder et al. 2018). However, the impact of
these shifting vegetation communities on wildfire risk specific to the City is not known at this time.
Plant communities in riparian habitats typically have higher foliar moisture than upland plants. This higher moisture
content can help to reduce damage from fire , and further, riparian corridors are often considered to be functional
barriers to the spread of wildfire (Pettit and Naiman 2007). However, some invasive plants such as the Giant reed
(Arundo donax) and tamarisk (Tamarix spp.) are highly flammable in California riparian systems , and are changing
these dynamics. However, both species recover rapidly from fire by regrowth from below-ground plant parts. By
contrast, cottonwoods, willows, and other native woody plants are less tolerant of direct exposure to fire. The invasive
plants mentioned above as well as Giant reed, a large, bamboolike grass, are making riparian systems fire-prone,
particularly in drier periods when this vegetation can increase fuel loads and subsequent wildfire risk (Linder et al.
2018).
Wildfire impacts in riparian zones can reduce canopy cover, resulting in increased water temperatures in creeks and
other shaded waterways, as well as increased sediment flux in stream beds and adjacent areas. These changes can
directly affect the food web of burned stream areas, increasing the density of algae as well as the potential to decrease
terrestrial vegetation inputs, resulting in more invertebrate algae consumers (Cooper et al. 2015).
Post-wildfire conditions can also alter runoff production and streamflow. Studies have shown that post-wildfire
streamflow can increase between 82 and 200 percent in the first year after a wildfire event (OPR et al. 2018b). High
intensity rainfall events increase the export of sediment flow in affected landscapes while lower intensity events
stimulate post-fire regrowth and increase the pace of hydrologic recovery. Research has also shown the floatation of
nutrients in post-wildfire streamflows in central portions of the state can affect nearshore marine and estuarine
waters. Specifically, post-fire runoff typically has elevated nitrogen concentrations due to the amount of biomass
burned in these landscapes during wildfire events (OPR et al. 2018b).
Post-Wildfire Runoff and Debris Flow
Wildfire events can result in post-wildfire scarring on effected landscapes and can alter the hydrologic response of
a watershed with the potential for even modest rainstorms to produce dangerous flash floods and debris flows
events, in which a mix of water, soils, vegetation, and fragmented rock can rush down mountainsides and funnel into
waterways. These events are due to vegetation loss and soil exposure on scarred landscapes, which would otherwise
support the stability of soils in steeper terrains. Post-wildfire runoff and debris flows can be affected by several factors
but are generally triggered by one of two processes: surface erosion caused by rainfall runoff, and landslid es caused
by rainfall seeping into the ground. While it is difficult to determine the potential risks of post-wildfire runoff prior to
wildfire events, the United States Geological Survey conducts post-fire debris-flow hazard assessments for select fires
in the Western U.S that are deemed susceptible to potential post-fire debris-flow events. These assessments analyze
burn severity, soil properties, and rainfall characteristics to estimate the probability and volume of debris flows that
may occur in response to a design storm and can help communities better prepare for these events . Design storms
are defined as hypothetical discrete rainstorms characterized by a specific duration, temporal distribution, rainfall
intensity, return frequency, and total depth of rainfall. While the effect of climate change on post-wildfire runoff and
debris flow is uncertain, climate change is projected to result in higher intensity rainfall events as well as “whiplash
events” with oscillations between extremely dry and extremely wet periods, potentially affecting post-wildfire hazards.
Additionally, drought inhibition of vegetation recovery in areas affected by wildfire can decrease soil stability and
increase the risk of post wildfire events (OPR et al. 2018b). Impacts from post-wildfire runoff and debris flow can result
in blockage of drainage systems causing further flooding, damage to infrastructure and property , as well as short-DRAFTPage 300 of 669
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term and long-term roadway closures. Impacts from these hazards are more likely to affect areas surrounding
waterways and areas with steeper terrain (USGS n.d.).
Key Findings and Policy Considerations
The increasing frequency of fire on chaparral landscapes have caused coastal sage shrubs and chaparral to shift
to grasses, including exotic grasses. Some research has suggested that annual and some perennial grasses have
the strongest effects on fire regimes and act as ecosystem transformers.
Wildfire impacts in riparian zones can reduce canopy cover, resulting in increased water temperatures in creeks
and other shaded waterways as well as produce increased se diment flux in stream beds and adjacent areas,
affecting the food web of burned stream areas and increasing the density of algae in waterways.
Post-wildfire runoff and debris flows can be affected by several factors but are generally triggered by one of two
processes: surface erosion caused by rainfall runoff, and landslid es caused by rainfall seeping into the ground.
While it is uncertain the effect climate change will have on post -wildfire runoff and debris flows event, climate
change is projected to result in higher intensity rainfall events as well as “whiplash events” with oscillations
between extremely dry and extremely wet periods, potentially affecting post-wildfire hazards.
WILDFIRE AND THE BUILT ENVIRONMENT
Anthropogenic Factors and Wildfire Risk
As noted extensively in research, while the effects of climate change are
projected to increase the frequency and severity of wildfires when they do
occur, approximately 95 percent of wildfires in the state are caused by
human ignition (Mann et al. 2016). This fact helps to place into
perspective the large influence human development has on the fire
regime in the state even with the increasing influence of climate change
throughout the 21st century. In assessing the influence of climate change on wildfire risk for the City, it is important to
recognize and consider the other anthropogenic factors influencing risk. As show in Figure 21, the risk of wildfire is
dependent on a variety of factors not excluding
biophysical factors that are affected by climate
change. These determinants, both anthropogenic and
biophysical, can be organized into three categories:
Resources (e.g., land use patterns, vegetation growth),
Ignitions (e.g., lightning, accidental ignitions, arson),
and Conditions (e.g., precipitation, wind, seasonal
variation).
Modeling conducted on the anthropogenic
influences of future wildfire risk in California note
that there are three dominant anthropogenic
mechanisms aside from climate change that will
heavily influence wildfire risk. These are increasing
ignitions, fire management practices, and the
modification of land cover. The research also
suggests that fire activity will increase in public
lands, especially those surrounding urban areas,
influenced by the promotions of fire suppression
through firefighting and the physical properties of
a dense urban environment (OPR et al. 2018b)
Source: Mann et al. 2016
Interactions of wildfire requirements as regulated by biophysical and
anthropogenic influences.
Figure 21 Biophysical and anthropogenic determinants
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A part of this increased risk from anthropogenic factors is the presence electric transmission l ines that travel from
power plant substations to electric distribution substations via utility easements called rights -of-way which are
present throughout the state including areas around the City as show in Figure 28. To reduce the risk of power
outages, damage, or wildfire, the rights-of-way are cleared of trees or vegetation that can contact the transmission
line. However, the combination of dry climate conditions and the seasonal high autumn winds in California can
increase the risk of trees or branches falling on transmission lines and causing power outages or wildfires. High winds
can also cause power lines to contact with one another and cause electrical arcs with sparks or hot molten materials
that can cause fires in dry grasses underneath transmissi on lines. While there are variety of factors which affect the
risk of wildfires being caused by damaged transmission lines, several recent wildfires have been blamed on electrical
utility infrastructure including a wildfire in San Diego County in 2007, the Thomas Fire in 2017, and the Camp Fire in
2019. As climate change contributes to drier conditions and tree mortality rates, the risk of wildfires caused by
transmissions lines will increase if actions are not taken to mitigate this risk (Congressional Res earch Service 2019).
Wildland Urban Interface (WUI)
As shown in Figure 22, portions of the City as well as areas immediately surrounding the City limits are increasingly at
risk of wildfire impacts. As noted above, climate change will increase the frequency of wildfire events and increase the
severity and average acreage burned when wildfire events do occur. Buildings and structures in and near VHFHSZ are
at increased risk of damage or destruction in the event of wildfire. Increased wildfire risk may also result in a loss of
housing stock and reduced regional housing affordability.
To better understand how anthropogenic influences, specifically development patterns, may affect wildfire risk, the
degree of urbanization within WUI zones in the City over several decades was analyzed. Processed satellite imagery
from the National Land Cover Database (Dewitz 2019) was used to determine changes in several land use categories
over three periods: 2001-2006, 2006-2011, and 2011-2016. Specifically, changes in high, medium, and low -intensity
development and developed open space over these three time periods for each of 18 WUI zones within the City were
assessed using a geographic information system (GIS) analysis. The results of the analysis are illustrated in Figure 22
and in Table 15.
Table 15 Percent Change in Developed Area for WUI Areas within the City 2001-2016
WUI Area Percent change in developed area in the WUI
2011-2016 2006-2011 2001-2006
Highland Area - - -
Foothill Area - - -
Buena Vista Area - - -
San Luis Drive Area - - -
Lizzie/Sunset Area - - 3.2%
Flora Area - - -
Tanglewood Area - - -
Woodbridge Area - - -
Fontana Area - - -
Margarita Area 86.3% - -
Tank Farm Road Area - - 0.2%
Prefumo Canyon Area - - -
Madonna Area - 0.2% 54.3%
North Broad - - -
Stoneridge - - 1.0%
Terrace Hill - - -
Righetti South - - -
Righetti North - 1.2% -
Source: National Land Cover Database processed by Cbec eco-engineering 2021 DRAFTPage 302 of 669
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Figure 22 Changes in the WUI areas within the City 2001-2016 DRAFTPage 303 of 669
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Overall, there was limited development within the WUI for the period of 2001 – 2016, with a few prominent
exceptions. The Madonna Area experienced over a 50 percent increase in developed area in the early 2000’s due to
commercial and residential development on former agricultural land along Los Osos Valley Road. Secondly, the
Margarita Area experienced an increase in dev eloped area of over 85 percent in the 2011 – 2016 period as a result of
residential development. These statistics represent a conservative estimate of development within the WUI areas,
because areas that are classified as ‘developed open space’ may include grass and other open vegetated areas and
in-fill into these zones by more intensive development is not considered. Instead, land cover needed to change from
non-developed to developed for inclusion in the assessment. Increases in these WUI areas, although limited, do
represent an increase in overall wildfire risk for the City, increasing the probability of ignitions that could have impacts
on other portions of the City as well .
While buildings within the WUI are at risk from direct flame contact and radiant heat during wildfire events, buildings
outside of the WUI are also at risk from ignition due to the spread of firebrands (or embers) that can initiate new spot
fires up to one mile ahead from the main fire front. The risk of spot fires initiated by embers depends on several
characteristics including fuel material type, condition of the fuel (e.g., live or dead fuels and moisture content levels),
the thermal degradation characteristics of the fuel, the combustion properties of the fuel, and environmental
conditions the fuel is subjected to (such as wind, relative humidity, temperature, and external heating condition) (U.S.
Department of the Interior 2019). Once embers have been transported to new locations and have the potential to
cause new spot fires, there are several pathways into structures such as eaves, vents, windows, roofs , fences, and
decking as well as potential fuels (e.g., mulch, landscaping, woody vegetation) surrounding structures , all of which
affect the risk of new spot fires igniting. Eaves and vents are seen to be significant sources of ignition for homes
during wildfire events, which have historically been included in homes for thermal efficiency and to minimize the
chance of moisture buildup in attics. The location and arrangement of homes and land uses can also contribute to
the overall fire risk within a community. Research has determined that fire risk within communities is primaril y
governed by structure-to-structure spread and can vary significantly by the density and flammability of homes and
associated landscaping within the WUI (Fire Protection Research Foundation 2015).
Key Findings and Policy Considerations
The risk of wildfire is dependent on a variety of factors not excluding biophysical factors that are affected by
climate change including Resources (e.g., land use patterns, vegetation growth), Ignitions (e.g., lightning,
accidental ignitions, arson), and Conditions (e.g., precipitation, wind, seasonal variation). Approximately 95
percent of wildfires in the state are caused by human ignition . However, climate change is projected to increase
the frequency and severity of wildfires , when they do occur (Mann et al. 2016).
The combination of dry climate conditions and the seasonal high autumn winds in California can increase the
risk of trees or branches falling on transmission lines and causing power outages or wildfires. While these
events have occurred historically, the effec t of climate change on biophysical features that increase the risk of
wildfires (e.g., precipitation, wind, seasonal variation) will increase the frequency and severity of wildfires from
transmission line ignitions.
There was limited development within the WUI in the city for the period of 2001 – 2016, with a few prominent
exceptions including the Madonna Area and the Margarita Area to the east of South Higuera Street. However,
buildings outside of the WUI are also at risk from ignition due to the spread of firebrands (or embers) that can
initiate new spot fires. DRAFTPage 304 of 669
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WILDFIRE AND COMMUNITY RESILIENCE
Wildfire Evacuation Route Analysis
Wildfire events in or near the City, when they do occur, could
result in emergency evacuations for certain areas. As show in
Figure 22, the areas at highest risk from wildfire impacts are
located in the WUI in the peripheral areas of the City Limits. As a
result, impacts to the City’s evacuation gateways (e.g., major
ingress and egress points in and out of the City) are not
projected to be affected by wildfires. Wildfire events in the
VHFHSZ near the Irish Hills Natural Reserve could potentially
have immediate impacts to some residential areas on Royal Way, Sterling Lane and Isabella Way . Additionally, areas
in the northeast of the City south of US 101 along San Luis Road are at risk from wildfire impacts and could potentially
compromise evacuation management when wildfires do occur in this area. Figure 23 identifies census block groups in
the City based on the percentage of vehicle access . Table 16 summarizes the number of census blocks in the City
relative to households with vehicle access. Although not located adjacent to any VHFHSZ, the neighborhoods north
of Foothill Boulevard include areas with higher percentage of households without access to a vehicle , likely due to the
high percentage of California Polytechnic State University at San Luis Obispo (Cal Poly) students who live in these
neighborhoods located adjacent to the campus. As part of Cal Poly’s emergency management planning, the
University has contracted with multiple bus and shuttle companies in County to provide emergency transportation
services, if needed, and worked with the County ’s Office of Emergency Services to ensure transportation resources
would be available during large scale emergency events (Cal Poly 2018).
Table 16 Wildfire Hazard Severity Zones and Percent o f No Vehicle Households per Block Group
Percent of No Vehicle Households Number of Block Groups
0-5% 17
5-10% 8
10-15% 3
15-20% 4
Source: Fehr and Peers 2021
The other portion of the City with a noticeably high percentage of households without access to vehicles is the
downtown area near Marsh Street and High Street, likely to due to the high-density housing and closer proximity to
goods and services in these areas. It is important to note here that areas of the City with lower vehicle access do not
necessarily mean increased vulnerability to emergency evacuation events but that more coordination is needed in
these areas including Car Less Collection Points during evacuation scenarios for residents without vehicles. The City
has identified Car Less Collection Points in this area including one in Meadow Park and one in the San Luis Obispo
Mission Plaza. As the City continues to implement its CAP, which includes efforts to reduce single-occupancy vehicle
trips and the needs for personal vehicle ownership, coordination and planning for evacuation scenarios for these
areas of the City will need careful consideration. DRAFTPage 305 of 669
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Note: No vehicle Households: Low = 0-5%, High = 5-21%; Source: Fehr and Peers 2021
Figure 23 Wildfire Hazard Severity Zones and Percent of No Vehicle Household per Block Group DRAFTPage 306 of 669
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As shown in Figure 24, areas with a higher share of older adults and youth include areas of moderate to very high
FHSZs. The Sinsheimer Neighborhood (Census Tract 110.01) is particularly vul nerable to wildfire impacts as the
neighborhood is adjacent to moderate to very high FHSZs, and has the highest percentage of elderly (20 percent)
and youth (7 percent) populations in the city, as well as the second highest percentage of disable d populations (12
percent). The Laguna Lake and Los Osos Valley Road (Census Tract 113) is also particularly vulnerable to wildfire risk,
with a high percentage of elderly residents (14 percent), disabled (10 percent) populations, and households
experiencing linguistic isolation (8 percent), which may present issues during emergency evacuation events.
Wildfire Smoke
While the City is at risk from the impacts of wildfires, the City and its residents are also susceptible to impacts of
smoke from wildfires in the coastal mountain ranges of central California and the Los Padres National Forest to the
east of the City. Wildfire smoke in the surrounding region and, due to wind patterns, wildfires along the central coast
in general, can greatly reduce air quality in the City and cause public health impacts as well as impacts to tourism and
normal community functions. Community public health factors that can increase the impacts of wildfire smoke
include the prevalence of asthma in children and adults; chronic obstructive pulmonary disease; hypertension;
diabetes; obesity; percent of population 65 years of age and older; and indicators of socioeconomic status, including
poverty, income, and unemployment. In addition to health risks from smoke inhalation, older adults may also be less
mobile and experience challenges with evacuation. Disadvantaged communities are vulnerable to wildfire impacts
because they score high on many of the public heal th factors and socioeconomic indicators described above. As
shown in Figure 25 and in Figure 26, disadvantaged communities and low-income areas in the City are also located in
high and very high fire hazard severity zones. This overlap may present challeng es for low-income residents, who
may not have resources to recover from wildfire events when they do occur or resources for increasing their
preparedness for wildfire events (e.g., defensible space improvements, emergency resources). Figure 27 includes the
high and very high fire hazard severity zones as well as the location and density of homeless encampments in the
City. The co-location of homeless populations and areas with higher wildfire risk places these populations a t higher
risk to wildfire impacts when they do occur as well as higher risk of wildfire occurrence due to ignitions at these
encampments.
Exposure to wildfire smoke, particularly exposure to vulnerable populations, can result in worsening of respiratory
symptoms, increased rates of cardio respiratory emergency visits, hospitalizations, and even death (Rappold et al.
2017). In the summer of 2020, wildfire smoke alerts were issued for the County due to poor air quality caused by the
Dolan Fire near Big Sur (The Tribune 2020a). Wildfire smoke can also have impacts on the labor market and the
economy in general, with air quality affecting the ability of outdoor workers to perform their work, industries that
operate partially or entirely outdoor (e.g., wineries, recreation activities, sporting ev ents), and the tourism industry
(Borgschulte et al. 2019).
Tourism and Economic Impacts
Wildfires can damage not only buildings and infrastructure, but also the natural environment, including portions of the
City and the areas in the County that serve as regional recreation and tourism opportunities. Hiking, camping, biking,
wine tasting, fairs, music festivals, and other popular tourism and recreation activities can be disrupted by wildfires both
during and in post-wildfire periods. In addition to reducing the abilities of individuals to partake in these activities, the
financial impacts caused by wildfires on these industries and the economy at large can be devastating. Major wildfires
often result in damage to transportation infrastructure and/or closure of roadways. Combined with potential impacts of
wildfire smoke from surrounding areas, wildfires may significantly reduce the overall desirability of the City and County
for visitors coming from other areas in the state as well as locations outside the state. DRAFTPage 307 of 669
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Sources: Data received from SLOCOG in 2021 and data downloaded from CAL FIRE in 2008 & 2020, City of San Luis Obispo in 2020
and County of San Luis Obispo in 2020
Figure 24 Share of Older Adults and Youth and Fire Hazard Severity Zone in the City DRAFTPage 308 of 669
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Sources: Data received from SLOCOG in 2021 and data downloaded from CAL FIRE in 2008 & 2020, City of San Luis Obispo in 2020
and County of San Luis Obispo in 2020
Figure 25 SLOCOG Identified Disadvantaged Communities and Fire Hazard Severity Zone in the City DRAFTPage 309 of 669
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Sources: Data received from SLOCOG in 2021 and data downloaded from CAL FIRE in 2008 & 2020, City of San Luis Obispo in 2020
and County of San Luis Obispo in 2020
Figure 26 Low-Income Populations and Fire Hazard Severity Zone in the City DRAFTPage 310 of 669
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Sources: Data received from SLOCOG in 2021 and data downloaded from CAL FIRE in 2008 & 2020, City of San Luis Obispo in 2020, 2021 and
County of San Luis Obispo in 2020
Figure 27 Homeless Encampments and Fire Hazard Severity Zone in the City DRAFTPage 311 of 669
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Public Safety Power Shutoffs
Beginning in 2019, electrical utilities in the state began to administer pre-emptive power shutoffs known as Public
Safety Power Shutoffs (PSPSs) to portions of the electricity grid that were experiencing increased risk of wildfire due
to specific weather conditions. PG&E, which operates the transmission lines in and around the City and has
administered several PSPS events throughout their service territory, use specific criteria when determining a PSPS
events (PG&E 2020). These include:
Low humidity levels (generally 20 percent or below)
High wind forecasts (sustained winds above 25 miles per hour and wind gusts above 45 miles per hour)
Low moisture content of live vegetation
Red Flag Warnings declared by the National Weather Service
Real-time ground observations from the PG&E Wildfire Safety Operations Center
PG&E has projected that future occurrence of these events will occur across their service territory more frequently
with most events occurring in the late summer and fall months during the historic fire season as shown in Figure 28.
Additionally, to help identify areas in the state with increased risk from wildfires caused by utility infrastructure, the
California Public Utilities Commission has developed a Fire Threat Map. As shown below in Figure 29, while future
frequency of PSPS events in the City is unknown, the City is in a location adjacent to “Elevated” and “Extreme” Fire
Threat Hazard Zones and transmission lines that help provide power to the City transverse both Elevated and
Extreme Fire Threat Hazard Zones, making the City more likely to experience PSPS events in the future as the climate
conditions that lead to these events become more common due to climate change.
Projected PSPS events per month based on weather data collected over the last 30 years.
Source: PG&E 2020
Figure 28 Potential PG&E PSPS Events per Year by Month
Electricity to the City is provided by PG via a 115 kilovolt (kV) tr ansmission line and three 21kV distribution lines from
the Morro Bay area. Currently, there are no redundant or backup facilities or resources for continuous electrical
service if a utility disruption were to occur to these facilities. Through coordination with PG&E, the City will be notified
during planned shut offs to any of the distribution lines servicing the City. DRAFTPage 312 of 669
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The CPUC Fire-Threat Map depicts areas with increased risk from wildfires caused by transmission lines and where enhanced fire safety regulations
have been enacted for utilities by the CPUC.
Source: CPUC 2021
Figure 29 California Public Utility Commission Fire Threat Map
Although residents in the City may not live or work in a high fire-threat area, their power may also be shut off if their
neighborhood or home relies upon a line that passes through an area experiencing extreme fire danger conditions.
During PSPS events, businesses and homes in the City lose power temporarily which can result in a variety of short -
term impacts on the community including access to pharmacies, grocery stores, and other essential businesses for
residents; secondary economic impacts on these businesses; loss of productivity for employees and employers; and
loss of products for businesses requiring refrigeration such as grocery stores and restaurants. PSPS events may also
affect telecommunication services such as cell towers and inhibit the ability to communicate information to residents
during emergency events. However, in January 2020, SB 431 was adopted, which requires telecommunications service
providers to develop backup power supplies to maintain minimum service for at least 72 hours during power
outages. The bill also requires that during a utility deisruption, telecommunications servicee providers must provide
communication services to emergency communication dispatch centers, emergency operations center s, federally-
qualified health centers, fire stations, general acute care hospitals, police stations, and rural health clinics.
Considering that PSPS events are projected to occur in the late summer and fall months which are typically the
warmest months in the City, the compounded effect of power loss during heat wave even ts could have considerable
public health impacts leaving residents and businesses without power and air conditioning during heat wave periods. DRAFTPage 313 of 669
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These impacts would be even more severe for populations who are at increased risk from heat -related illnesses
including persons over the age of 65, infants and children, individuals with chronic health conditions (e.g.,
cardiovascular disease, asthma), low-income populations, athletes, and outdoor workers (CDC 2019). Residents who
require at home supplemental oxygen , refrigerated medications, and other medical equipment that requires
electricity are also at increased risk during PSPS events. Additionally, a loss of power can disrupt heating, ventilation,
and air conditioning (HVAC) systems in homes and business, which are critical for maintaining indoor air quality. The
combination of PSPS events occurring during periods of poor air quality caused by wildfire smoke can lead to poor
indoor air quality and result in increased public health impacts.
Aside from the power supply related impacts of PSPS events, recent research has shown that PSPS events likely
result in a ‘looming threat’ that can be linked to unintended poo r mental health outcomes compounded by self -
reported trauma lingering from previous wildfire experiences. Specific concerns expressed by individuals affected
by PSPS events in 2019 included, rotting food in refrigerators, people with medical needs being unable to access
needed electricity, in addition to personal concerns about individuals’ ability to conduct their normal daily
activities. Other concerns included worries about how the PSPS events affected their ability to go to work or
school, having to personally care or find childcare for children who were out of school due to the PSPS, and being
unable to use air conditioning or a fan when needed. Regardless of actual impacts, the persistent “looming threat”
of PSPS events for residents was a clear concern that led to worse mental health outcomes for some (Wong-Parodi
2020).
Local Impacts from Regional Wildfires
As shown in Figure 120, climate change is projected to increase the frequency and severity of wildfires not on ly in and
near the City but at the County and regional level as well. Wildfires that occur at other locations in the County can
have secondary impacts on the City as well including short-term impacts from route closures or delays, regional
wildfire smoke impacts as discussed abo ve, and economic impacts for employees who work in affected areas.
Wildfires that occur in the County or in the larger central coast region can also result in temporary or permanent
wildfire refugees who need to relocate due to property loss or damage and may relocate in the city. This influx of
new residents can place increased pressure on local resources and infrastructure as well as exacerbate housing supply
and affordability issues that already exist (National Academies of Sciences, Engineering, and Med icine 2020).
Community Wildfire and Wildfire Smoke Concerns
As part of the community priorities survey, when asked about their concern for wildfires and wildfire smoke, as shown
in Figure 30, 94 percent of participants indicated “Somewhat” or “Very” concerned. When asked about whether they
have been personally affected by either event, 64 percent of respondents indicated “Somewhat” or “Very” for
wildfires and 92 percent of respondents indicated “Somewhat” or “Very” for wildfire smoke. Additionally, wildfire
smoke was of paramount concern for individuals within the lowest income group (i.e., 84 percent). Renters and
individuals between the ages of 18 and 24 express ed the highest level of concern for wildfire and wildfire smoke.
Individuals who identify as White or Caucasian express a slightly higher level of concern both wildfire and wildfire
smoke than individuals who identify as all other Races/Ethnicities . DRAFTPage 314 of 669
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Sources: Resilient SLO Community Priorities Survey
Figure 30 City Resident’s Wildfire and Wildfire Smoke Concern and Impact
Key Findings and Policy Considerations
Wildfire events in the VHFHSZ near the Irish Hills Natural Reserve could potentially have immediate impacts to
some residential areas on Royal Way, Sterling La ne and Isabella Way. Additionally, areas in the northeast of the
City south of US 101 along San Luis Road are at risk from wildfire impacts and could potentially compromise
evacuation management when wildfires do occur in this area.
The City serves as regional employment center, regional destination for tourism, and home to a university (Cal
Poly) with approximately 20,000 students. These factors create an environment in which the City experiences a
large influx of daily visitors to the City with a daytime population is estimated to be 90,000 (City of San Luis
Obispo 2021c). If a wildfire event was to occur in or near the City during daytime hours, evacuation management
would be particularly difficult and pose additional challenges due to this large influx of daily visitors. Additionally,
because US 101 serves the main commuter corridor for locations north and south, wildfire e vents that occur along
this route causing route closures (e.g., Cuesta Grade) can disproportionately impact employers and employees in
the City.
While the majority of the City is not at high risk from direct wildfire impacts, regional PSPS events have the potential to
result in secondary impacts. Specifically, PSPS events occurring during heat wave events could have considerable
public health impacts, leaving residents and businesses without power and air conditioning and further threaten
residents who are medically-reliant on electricity for supplemental oxygen and refrigeration.
The confluence of PSPS, bad air quality, wildfire threat, and high heat days underscores the importance of homes
and businesses as places of potential refuge.
The Sinsheimer Neighborhood (Census Tract 110.01) and the Laguna Lake and Los Osos Valley Road (Census
Tract 113) areas are particularly vulnerable to wildfire impacts as these areas of the City are located near
moderate to very high FHSZs and include higher percentages of e lderly (20 percent) and youth (7 percent)
populations. Additionally, these areas have a high percentage of households experiencing linguistic isolation (8
percent) which may present issues during emergency evacuation events.
5%
16%
79%
6%
20%
74%
35%
43%
21%
7%
39%
53%
0%
20%
40%
60%
80%
100%
Not at all Somewhat VeryPercent of RespondentsLevel of Concern
WILDFIRE SMOKE & WILDFIRES
Which of the following climate change impacts are you concerned about [Wildfire]?
Which of the following climate change impacts are you concerned about [Wildfire Smoke]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Wildfire]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo [Wildfire
Smoke]?
Total Responses = 328 DRAFTPage 315 of 669
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Exposure to wildfire smoke, particularly exposure to vulnerable populations, can result in worsening of respiratory
symptoms, increased rates of cardiorespiratory emergency visits, hospitalizations, and even death (Rappold et al.
2017). Wildfires can damage not only buildings and infra structure, but also the natural environment, including
portions of the City and the areas in the County that serve as regional recreation and tourism destinations.
Accordingly, wildfire smoke has the potential to harm the local economy by reducing tourism and its related
industries.
2.5.3 Adaptive Capacity for Wildfire Impacts
As discussed in the previous section, portions of the City are at considerable risk from wildfire impacts as well
secondary impacts to residents and businesses from wildfire smoke and PSPS events. However, wildfire risk is not a
new hazard for the City and partner agencies have taken considerable steps to mitigate wildfire impacts when they
do occur.
WILDFIRE RISK REDUCTION AND PREPAREDNESS
Wildfire risk is addressed in the City’s Annex G of the County’s Multi-Jurisdictional Hazard Mitigation Plan and
includes a set of mitigation goals, objectives, and actions specifically focused on addressing wildfire risk. Additionally,
the City of San Luis Obispo adopted the Community Wildfire Protection Plan in 2019 which focuses on fire protection
planning in the City, working on minimizing wildfire risk to areas in and around the City limits. Section IV of the plan
includes a comprehensive set of goals and policies with implementation timelines to reduce wildfire risk in the
community. The strategy categories include:
Education policies to prepare response organizations, communities, the public, and policy makers regarding
appropriate community actions and interactions to reduce the unwanted impacts of fires in the wildland urban
interface.
Fuels Management policies to mitigate the unwanted impacts of wildfires on communities through proper
vegetation management techniques that reduce hazardous fuels and the resulting wildfire intensity.
Planning policies to help mitigate wildfire impacts in the City through community planning (including new
resilient community design, retrofitting existing communities, and community recovery from the impact of fire),
response planning, evacuation planning, and preparedness planning for responders, communities, individuals,
animals, and livestock.
Emergency Response policies to mitigate wildfire impacts on life, property, and resources by having an efficient
and effective response that includes properly trained personnel, appropriate equipment, and a community
prepared to take appropriate action or evacuat e.
Ignition Resistance policies mitigate structural ignitions from radiant heat, flame contact, or embers from wildland
urban interface fires.
In regard to helping prepare the general public for wildfire hazards, t he City’s Fire Department has provided a
comprehensive set of videos and resources through the Prepare SLO information campaign to inform residents and
businesses on how to reduce risk from wildfires, prepare for wildfire events when they do occur, as well as how to
recover from wildfire impacts. In addition to the City’s wildfire preparedness efforts, the County’s Office of Emergency
Services (OES) works to help coordinate emergency response efforts between the County, the City, and relevant
partner agencies including CAL FIRE during emergency events. The County OES also manages the Ready SLO website
which provides a comprehensive set of resources to help County residents prepare for hazard events including
information needed in preparing for hazards, key hazard resources such as evacuation routes , and the County’s
emergency alert system which residents can sign up for to receive notifications and alerts during emergency events. DRAFTPage 316 of 669
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ENERGY RESILIENCE
In recent years, PG&E has also taken considerable steps to reduce the severity of impacts of PSPS events when they
do occur (PG&E 2020). These steps include:
electricity grid upgrades to break the grid into smaller parts to limit the size of outages when they do occur;
preparing microgrids in areas most likely to experience PSPS events to safely provide electricity to areas th at are
safe to keep energized during PSPS events;
supporting communities and customers to develop their own multi -customer or community-level microgrids;
implementing system hardening improvements including installing stronger, fire resistant poles, covered lines
and conducting targeted undergrounding in areas of high wildfire risk; and
using better weather monitoring technology and installing new weather stations to more precisely forecast the
weather that could lead to PSPS events.
The City also benefits from the efforts undertaken by the San Luis Obispo County Fire Safe Council (Fire Safe
Council). The Fire Safe Council is a diverse group of local and regional stakeholder that work to create fire safe
communities in the County. The group provides educati onal resources to residents and businesses to reduce
wildfire risk at the neighborhood and property level as well as help manage and fund wildfire fuel reduction
projects throughout the County .
Central Coast Community Energy (3CE) is a Community Choice Energy agency established by local communities to
source clean and renewable electricity for Monterey, San Benito and Santa Cruz counties , and parts of Santa
Barbara and San Luis Obispo counties (including the City of San Luis Obispo ). 3CE has begun to implement
Resiliency Programs to help increase energy resilience for their customers. Most notably, 3CE has a llocated $25
million to create the Uninterruptible Power Supply (UPS) Fund to accelerate and help finance the adoption of
reliable backup power for public and private entities operating critical facilities , helping to ensure continuity of
service and operations during PSPS events. 3CE is also working to develop a Residential Resiliency Incentive
Program 2021 to help residential customers increase energy resilience through reliable backup power systems.
UTILITY DISRUPTION EMERGENCY OPERATIONS
Annex I of the City’s Comprehensive Disaster Leadership Plan focuses specifically on procedures to ensure a
continuity of operations during a Utility Disruption event affecting portions or all of the City. This document is in in
part a response to the potential increase in PSPS events effecting the City as well as other climate related hazards
that may affect utility services. The City of San Luis Obispo has a dopted the Incident Command System, the Standard
Emergency System, and the National Incident Management System as the emergency organization and the
emergency management system for response to a Utility Disruption event impacting the City . The document includes
a set of actions to be taken prior to a Utility Disruption when a ny notification of anticipated severe fire weather
concerns are issued by PG&E as well as assigned roles for appropriate City departments during a Utility Disruption
event. As stated in Annex I, the PG&E event notification will include:
Estimated start time of a potential event
Forecasted weather duration
Estimated time range to full restoration
Number of medical baseline customers in the potentially impacted area
Weather and Utility Disruption information can be found at www.pge.com/weather
Maps that include boundaries of the area subject to de-energization and affected circuits will be posted at
www.pge.com/pspsportal DRAFTPage 317 of 669
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Annex I also includes an initial assessment of what impacts may occur to various operations in the City during a Utility
Disruption including disruptions to leadership operation, emergency reporting, evacuation, resource center
information, animal sheltering, school disruptions, emergency services, City utilities (discussed below), transportation
systems, communication systems, emergency public information communications, and security. The document also
includes recovery actions to be taken once a Utility Disruption event has ended.
As a result of potential future PSPS, the City’s Utility Department has begun to develop precautionary measures to ensure
the City is able to provide uninterrupted water service during short-duration power outages. The City’s 2020 UWMP
includes discussion of efforts to prepare for power outages of up to seven days and to ensure water is provided to critical
facilities including the City’s Emergency Operations Center, area hospitals, the SLO County Emergency Operations Center,
the Cal Poly campus, and the SLO County airport. The City has a set of portable generators that are deployed as needed to
various locations in the City’s water conveyance system during power outages. The City also has a set of permanent back-
up generators at key facilities including the City’s Water Treatment Plant, Whale Rock Reservoir, and other pump stations
and lift stations to ensure uninterrupted water service is provided in power outage scenarios.
For these reasons, the adaptive capacity ranking for wildfire risk is medium.
2.5.4 Vulnerability Summary
As discussed above, climate change is projected to cause an increase in the size and frequency of wildfire events due to
changes in average temperatures, extreme heat events, and long-term drought scenarios over the 21st century. While
the City includes some areas that are a high risk from wildfire impacts, the majority of the City is at moderate risk from
direct wildfire impacts. However, due to the regional characteristics of wildfire impacts the City is still vulnerable to
secondary wildfire impacts including untended consequences of PSPS events as well as public health impacts from
regional wildfires that generate wildfire smoke and poor air quality in the City. These changes will result in varying
impacts on the City and its residents as discussed above. Based on the analysis of various impacts discussed in Section
3.3.2, the City’s potential impact scoring is High (3). Wildfire impacts that are unique to the City and should be given
increased consideration during the adaptation strategy development process are discussed below.
Natural System Findings
The increasing frequency of fire on chaparral landscapes have caused coastal sage shrubs and chaparral to shift
to grasses, including exotic grasses. Some research has suggested that annual and some perennial grasses have
the strongest effects on fire regimes and act as ecosystem transformers.
Wildfire impacts in riparian zones can reduce canopy cover, resulting in inc reased water temperatures in creeks
and other shaded waterways, as well as increased sediment flux in stream beds and adjacent areas, affecting the
food web of burned stream areas and increasing the density of algae in waterways.
Post-wildfire runoff and debris flows can be affected by several factors but are generally triggered by one of two
processes: surface erosion caused by rainfall runoff, and landslid es caused by rainfall seeping into the ground.
While it is uncertain the effect climate change will have on post-wildfire runoff and debris flow events, climate
change is projected to result in higher intensity rainfall events as well as “whiplash events” with oscillations
between extremely dry and extremely wet periods, potentially affecting post-wildfire hazards.
Built Environment Findings
The risk of wildfire is dependent on a variety of factors not excluding biophysical factors that are affected by
climate change including Resources (e.g., land use patterns, vegetation growth), Ignitions (e.g., lightn ing,
accidental ignitions, arson), and Conditions (e.g., precipitation, wind, seasonal variation). A pproximately 95
percent of wildfires in the state are caused by human ignition . However, climate change is projected to increase
the frequency and severity of wildfires, when they do occur (Mann et al. 2016).
The combination of dry climate conditions and the seasonal high autumn winds in California can increase the
risk of trees or branches falling on transmission lines and causing power outages or wildfires. While these
events have occurred historically, the effect of climate change on biophysical features that increase the risk of DRAFTPage 318 of 669
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wildfires (e.g., precipitation, wind, seasonal variation) will increase the frequency and severity of wildfires from
transmission line ignitions.
There was limited development within the WUI in the city for the period of 2001 – 2016, with a few prominent
exceptions including the Madonna Area and the Margarita Area to the east of South Higuera Street. However,
buildings outside of the WUI are also at risk from ignition due to the spread of firebrands (or embers) that can
initiate new spot fires.
Wildfire events in the VHFHSZ near the Irish Hills Natural Reserve could potentially have immediate impacts to
some residential areas on Royal Way, Sterling Lane and Isabella Way. Additionally, areas in the northeast of the
City south of US 101 along San Luis Road are at risk from wildfire impacts and could potentially compromise
evacuation management when wildfires do occur in this area.
Community Resilience Findings
The City serves as regional employment center, regional destination for tourism, and home to a university (Cal
Poly) with approximately 20,000 students. These factors create an environment in which the City experiences a
large influx of daily visitors to the City. If and when a wildfire event was to occur in or near the City during
daytime hours, evacuation management would be particularly difficult and pose additional challenges due to this
large influx of daily visitors. Additionally, because US 101 serves the ma in commuter corridor for locations north
and south, wildfire events that occur along this route causing route closures (e.g., Cuesta Grade) can have a
disproportionate impact on employers and employees in the City.
While the majority of the City is not at high risk from direct wildfire impacts, regional PSPS events that affect the City
will result in a set of potential secondary impacts. Specifically, PSPS events occurring during heat wave events could
have considerable public health impacts, leaving residents and businesses without power and air conditioning and
further threaten residents who are medically-reliant on electricity for supplemental oxygen and refrigeration.
The confluence of PSPS, bad air quality, wildfire threat, and high heat days underscor es the importance of homes
and businesses as places of potential refuge.
The Sinsheimer Neighborhood (Census Tract 110.01) and the Laguna Lake and Los Osos Valley Road (Census
Tract 113) are particularly vulnerable to wildfire impacts as these areas of the City are located near moderate to
very high FHSZs and include the higher percentages of elderly (20 percent) and youth (7 percent) populations .
Additionally, these areas have a high percentage of households experiencing linguistic isolation (8 percent) w hich
may present issues during emergency evacuation events.
Exposure to wildfire smoke, particularly exposure to vulnerable populations, can result in worsening of respiratory
symptoms, increased rates of cardiorespiratory emergency visits, hospitalization s, and even death (Rappold et al.
2017). Wildfires can damage not only buildings and infrastructure, but also the natural environment, including
portions of the City and the areas in the County that serve as regional recreation and tourism destinations.
Accordingly, wildfire smoke has the potential to harm the local economy by reducing tourism and its related
industries.
Wildfire Vulnerability Score
Adaptive Capacity: Medium (2)
Potential Impact: High (3)
Vulnerability Score: 4
2.6 PRECIPITATION AND FLOODING ANALYSIS
This section discusses future increases in annual precipitation and increases in the frequency and severity of large
storm events in watersheds affecting the City. The section analyzes how these changes are likely to impact the City DRAFTPage 319 of 669
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and its population as well as highlights what capacity the City and partner agencies already have in place to address
these future impacts.
2.6.1 Future Exposure to Changes in Precipitation and Flooding
According to Cal-Adapt, the historic average annual precipitation in the City is 21.2 inches. As shown in Table 17, the
average annual precipitation in the County is projected increase to 22.6 inches in the near-term and 22.6 inches in
the midterm under the high emissions scenario. Average annual precipitation is projected to be 21.6 inches under the
medium emissions scenario and 25.2 inches under the high emissions scenario in the late century (CEC 2021a).
Although the City is anticipated to experience only moderate increases in annual pre cipitation, research indicates that
the majority of the increase in annual rainfall is anticipated to occur during large storm events, which are projected to
increase in size and frequency in the future.
Table 17 Changes in Average Annual Precipitation in City of San Luis Obispo
Average Annual Precipitation Historic Average Annual
Precipitation (1961-1990)
Near-Term
(2021-2050)
Midterm
(2035-2064)
Late-Century (2070-2099)
Low Emissions High Emissions
Average Annual Precipitation (inches) 21.2 22.6 22.6 21.6 25.2
Notes: RCP = Representative Concentration Pathway.
Source: CEC 2019a
CLIMATE-INFORMED FLOOD RISK MODELING
As part of the development of the vulnerability assessment, a climate-informed flood risk modeling exercise was
conducted to understand how changes in precipitation caused by climate change could affect the frequency and
severity of large storm events (e.g., 100-year storm event) and how these changes would affect th e flow of water
through the City’s existing flood plains. The following section discusses the process used to develop this modeling
and a summary of the modeling results.
Flooding Characteristics
Two interchangeable, technical terms that characterize floo d frequency are used throughout the section and are
defined as follows:
Recurrence Intervals: A common way to describe floods is by stating their recurrence intervals, which refer to how
often, on average, a given flood may occur. A 100 -year event, for example, is described as an event that may
occur about once in every 100 years, on average. However, this terminology can be misleading because flood
events are statistical occurrences, and events may occur more frequently than their recurrence interval sugge sts.
Exceedance Probability: The exceedance probability of a given flood event is the percent chance that a larger
flood will occur in any given year, and it is calculated by dividing the number 1 by the recurrence interval. Thus,
the “100-year event” becomes the “1-percent exceedance event,” or a flow rate that has a 1-percent chance in any
given year of being equaled or surpassed by a larger flow rate. This representation, although interchangeable
with the recurrence interval, provides a more helpful way to think about flood risk.
There are several overall mechanisms by which flooding can occur:
dam inundation flooding, in which impounded water is released because of dam breaching;
localized flooding, which occurs when intense rainfall overwhelms the capacity of local drainage infrastructure ;
causing the ponding of water; and
riverine flooding, which occurs when channels (i.e., the relatively deep, narrow sections of creeks and rivers)
cannot contain the flow volume moving through them, causing water to spill out into the overbank areas (i.e., the
relatively wide, flat regions on one or both sides of the channel, also called “floodplains”). DRAFTPage 320 of 669
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According to the Annex G of the County’s HMP, the City is not at risk of dam inundation flooding, as there are no
major reservoirs within the watershed, and localized flooding is considered a minimal risk. The highest flooding
concern for the City is riverine flooding, which may include “flash” flood risks (San Luis Obispo County 2019b).
Floods occur when the amount of water within the creek channels exceeds the channel capacity, causing water to spill
over the banks and into the surrounding land. In these flat, flood-prone areas beyond the channel, called floodplains,
slow moving or stagnant water that escapes the channel may remain until water levels within the channels recede or
the areas are drained by infrastructure, percolation, or evapotransp iration. Naturally, these floodplain areas would
have been flooded every few years, but as the City developed onto portions of the floodplains of the creeks within
the San Luis Obispo Creek watershed, channel incision and flood protection measures constrai ned flows to the
creeks. During periods of intense rainfall, however, the watershed outflow, including urban runoff, can exceed the
capacity of the channels. Under existing conditions, different creeks within the watershed may experience flooding
every 10-25 years (Questa Engineering Corporation 2003). The goal of the flood impacts assessment was to
determine how the current level of flood risk is projected to vary as a result of climate change.
Flood Risk Modeling Methodology
To understand how flood risk for the City is likely to change in the future due to climate change, modeling software
was used to assess projected changes in rainfall and analyze how these changes would affect flood inundation. The
first step in determining the change in flood risk involves conducting long-term hydrologic modeling of the San Luis
Obispo Creek watershed with historic and future daily precipitation data to understand changes in stream flow. This
type of model simulates the ability of the watershed to store and release wate r over time through various processes,
and by determining how quickly water is passed through the system, the model can be used to understand how flow
within creek channels will respond to rainfall. It is based on physical watershed attributes such as slop e, drainage area,
land cover, geology, channel geometry, and initial soil moisture conditions, which control how much of the
precipitation will be converted to streamflow versus being held within the watershed or lost to the atmosphere. For
this analysis, a hydrologic model was developed using the Soil and Water Assessment Tool platform (SWAT), which
was calibrated using historical gridded precipitation data (Livneh et al. 2015) and United State Geological Survey daily
flow records from 1978 – 1985 for the Lower SLO Creek gage.
The SWAT hydrologic model was then used to simulate both historic (1970 – 1999) and future (2070-2099) daily
precipitation records from 10 General Circulation Models recommended by the California Department of Water
Resources for this type of modeling. These atmospheric models simulate global patterns for temperature,
precipitation, and other atmospheric data over long periods of time. For the purpose of this assessment, the high
emissions scenario over the long-term period (2070-2099) was used for this exercise. The 30-year future daily
precipitation records were then simulated in the SWAT model, in addition to historic precipitation records (1970 –
1999). Using the average of the 10 future simulations, f low frequency statistics (England et al. 2019) were computed to
determine how different flood events (e.g., the 100-year event) are projected to vary as a result of climate change .
To assess flood impacts on the City’s existing floodplains from changes in precipitation, further hydrauli c modeling
was needed. Hydraulic modeling is a process that uses the physical representation of a river network, including
channel geometries, land slopes, surface characteristics, and structural information, to understand how quickly water
moves through different channel reaches, how deep it is, and where overbank flooding may occur. For example,
water flowing across a smooth concrete surface will move much faster than water passing through vegetation or
through gravelly waterways. From a hydraulics perspe ctive, the vegetation is said to have higher ‘roughness’ than the
concrete, and empirical values are available to indicate this concept of roughness within hydraulic models. Likewise,
channels that have steeper slopes or greater cross -sectional areas will be able to move water more quickly than those
with gentler slopes or smaller areas. Bridges, culverts, and other structures can also greatly affect flow. As illustrated
in Figure 31, a suite of hydraulic models using the HEC -RAS platform was developed for the Waterway Management
Plan (Questa Engineering Corporation 2003), spanning San Luis Obispo Creek from Reservoir Canyon to Avila Beach,
Prefumo Creek from Madonna Road to the San Luis Obispo Creek confluence, East Fork San Luis Obispo Creek and
portions of its tributaries, and portions of Stenner, Brizziolari, and Old Garden Creeks. These models were adapted to
the current study by scaling the peak flows used in the WMP by the factors from Table 18. The 500-year event was
not studied for the Waterway Manag ement Plan, but 500-year flow rates were determined for Federal Emergency DRAFTPage 321 of 669
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Management Agency (FEMA) flood insurance studies (FEMA 1978) for all examined creeks except for East Fork San
Luis Obispo Creek. DRAFTPage 322 of 669
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Source: cbec eco-engineering 2021
Figure 31 HEC-RAS Hydraulic Model Extent DRAFTPage 323 of 669
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Table 18 Climate-induced Changes in Peak Stream Flow for the San Luis Obispo Creek Watershed
Flood Event
(Return Interval)
Percent chance of flood
occurring in any given year
Percent increase in peak stream flow
90th Percentile 50th Percentile (median) 10th Percentile
500-Year 0.2% 122% 38% 4%
200-Year 0.5% 116% 38% 4%
100-Year 1% 110% 38% 4%
50-Year 2% 103% 37% 4%
20-Year 5% 93% 35% 3%
10-Year 10% 84% 33% 3%
5-Year 20% 73% 29% 3%
2-Year 50% 51% 28% 8%
1-Year 99% 64% 17% -31%
Source: cbec eco engineering 2021. The late century (2070-2099), RCP 8.5 scenario was used to determine flood impacts.
For each flood event, historic flow rates (using WMP hydrology for 10-year, 50-year, and 100-year and FEMA [1978]
hydrology for the 500-year excluding East Fork of San Luis Obispo Creek) and scaled future peak flow rates based on
projections from Table 18 were simulated in the HEC-RAS models representing channel conditions in the early 2000’s.
Flood inundation maps were then generated by extending mode led water surface elevations over a digital elevation
model of the watershed (Woolpert 2019) to determine inundated acreage and depth of water on floodplain areas
(not including channels or Laguna Lake) that were physically connected to flood sources. The assessment was divided
into 9 regions to understand how flood impacts varied throughout the City and outlying areas.
Modeling Results
The following section discusses the results of the climate -informed flood risk modeling exercise. Table 18 includes the
modeling results for various size storm events in the San Luis Obispo Creek watershed for the long -term period
(2070-2099) under a high emissions scenario.
As shown in Table 18, the 10th percentile results indicate an extremely dry scenario, which experiences decreases in
flow for events with less than a 2-year recurrence interval, while the 90th percentile results represent an extremely
wet future scenario and results in peak flows more than doubling for events that occur every 50 or more years. For
flood events occurring more rarely than every 2 -years, flows are expected to increase across all scenarios including
the 10th percentile projection. Overall, the median projection rep resents the best available estimate at this time for
the San Luis Obispo Creek watershed for how peak flows are likely to change if global GHG emissions maintain the
high emissions scenario trajectory for the long -term period.
The climate-induced increases in flood magnitude are due to increases in precipitation intensity. As the atmosphere
warms, its ability to hold water vapor increases. While total annual precipitation in different parts of the state is projected
to increase, decrease, or stay the same depending on the location, the trend of increasing rainfall within shorter periods
of time (increasing intensity) is projected to occur broadly (OPR et al. 2018). In this way, even areas that may become
drier and experience water scarcity as a result of climate change may also experience increased flood risk. Based on
California’s location next to the Pacific Ocean, the state is exposed to the atmospheric river (AR) phenomenon, a narrow
corridor of concentrated moisture in the atmosphere. California is subject to precipitation from an AR that transports
water vapor from as far south as Hawaii to the state. The presence of the AR contributes to the frequency of “wet years”
in the state, when there is an above-average number of AR storms and above-average annual precipitation. Projected
peak stream flow increases are also greater for larger (less frequent) flood events than for smaller ones, as a result of the
watershed’s diminishing ability to absorb increasingly high levels of rainfall. For example, following a long, dry summer,
the land surface, soils, and vegetation will have a relatively high capacity to hold incoming rain and very little stream flow
may be generated from a notable amount of rainfall. In the mid-winter months, after a series of precipitation events has
passed through, the soils are relatively saturated and generate runoff more quickly. For very large precipitation events,
the capacity of the watershed to absorb incoming rainfall can be quickly exceeded, causing large increases in stream DRAFTPage 324 of 669
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flow within the system. For the median scenario, peak flow rates are projected to increase from 17 percent to 38 percent
for events that occur every year to every 500 years, on average, as show in Table 18.
While research indicates that the frequency of large storms events does increase in these wet years, the most severe
flooding from ARs may not be in wet years (Swain et al. 2018). The largest flooding impacts are caused by persistent
storm sequences on sub-seasonal timescales (i.e., short time periods, typically 2 weeks to 3 months), which bring a
significant fraction of annual average precipitation over a brief period. These storms events are similar to the Great
Flood events of 1861–1862, which caused widespread damage throughout northern California (Swain et al. 2016).
Based on current climate modeling, the frequency of these large storm sequences over short timeframes is projected
to increase noticeably under the high emissions scenario. It is estimated that a storm similar in magnitude to the
Great Flood event is more likely than not to occur at least once between 2018 and 2060 (Swain et al. 2018).
Although annual precipitation is anticipated to increase in the City and the larger central coast region, California’s
climate oscillates between extremely dry and extremely wet periods with annual precipitation varying widely from year
to year. Climate change is anticipated to exacerbate these seasonal extremes with dry periods becoming dryer and wet
periods becoming wetter (OPR et al. 2018b:19). As a result, the frequency and severity of large storm events are
anticipated to increase as well. These oscillations between extremely dry and extremely wet periods, which have
occurred historically in the state, are anticipated to become more severe with rapid shifts from dry to wet periods known
as “whiplash events” (Swain et al. 2016). As Swain et al. note in their research, the recent 2012–2016 drought followed by
the 2016–2017 flood events throughout the state serve as a good example of the type of whiplash events that will occur
more frequently over the next century. These types of events are estimated to increase by approximately 100 percent in
southern California, with increases in frequency occurring largely after 2050 (Swain et al. 2016).
2.6.2 Precipitation and Flooding Sensitivities and Impact
This section discusses the City’s existing sensitivities to increases in annual precipitation and flooding events ,
analyzing potential effects on the City including a discussion of general impacts as well as secondary impacts. This
impact analysis focuses specifically on impacts to the City’s built environment and transportation network.
FLOODING AND NATURAL SYSTEMS
Future Flood Mapping Results
Based on hydraulic modeling discussed above, future floodplain maps
were generated to understand how changes in precipitation for the 10-
year, 50-year, and 100-year storms events would impact the City as
shown in Figures 32 through 40. Additional modeling for the 10-year,
50-year, 100-year, and 500-year storms events is included in Appendix
A. Figures 32 through 40 show the generated depth maps for historic
and future (long-term high emissions [RCP 8.5] scenario) conditions for
the 10-year (Q10) and 100-year (Q100 events within the San Luis Obispo Creek – Stenner Creek and San Luis Obispo Creek
– Prefumo Creek confluence areas. These figures provide an illustration of the future extent of flood plains in the San Luis
Obispo Creek watershed. However, there are limitations preventing these maps from being used for more detailed or more
absolute flood extent delineations for historic and future conditions. One main limitation is the reliance upon hydraulic
models that are almost two decades old and do not cover all areas of the City as well as an uncertain range of possibilities
for future precipitation and future global emissions trends during the late-century period. However, the mapping exercise is
useful for indicating the locations and extents of relative flood impacts that may reasonably be expected to occur due to
climate change under the late-century high emissions scenario.
To further understand relative flood impacts, the hydraulic model domain was divided into nine analysis regions
where changes in inundated area in acres and average depth on the floodplain (ft) were compared between historic
and future conditions for each flood event, as shown in Tables 19 and 20. To determine these statistics for floodplain
areas, the regions within the creek channels and Laguna Lake were removed from the analysis . DRAFTPage 325 of 669
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Source: cbec eco engineering 2021
Figure 32 Flood Depth: Full Extent - Q100 (Historic) DRAFTPage 326 of 669
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Source: cbec eco engineering 2021
Figure 33 Flood Depth: SLO-Stenner - Q10 (Historic) Flood Depth - Q100 (Historic) DRAFTPage 327 of 669
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Source: cbec eco engineering 2021
Figure 34 Flood Depth: SLO-Stenner - Q10 (Future 2070-2099 – RCP 8.5) DRAFTPage 328 of 669
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Source: cbec eco-engineering 2021
Figure 35 Flood Depth: SLO-Stenner - Q100 (Historic) DRAFTPage 329 of 669
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Source: cbec eco-engineering 2021
Figure 36 Flood Depth: SLO-Stenner - Q100 (Future 2070-2099 – RCP 8.5) DRAFTPage 330 of 669
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Source: cbec eco-engineering 2021
Figure 37 Flood Depth: SLO-Prefumo - Q10 (Historic) DRAFTPage 331 of 669
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Source: cbec eco-engineering 2021
Figure 38 Flood Depth: SLO-Prefumo - Q10 (Future 2070-2099 – RCP 8.5) DRAFTPage 332 of 669
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Source: cbec eco-engineering 2021
Figure 39 Flood Depth: SLO-Prefumo - Q100 (Historic) DRAFTPage 333 of 669
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Figure 40 Flood Depth: SLO-Prefumo - Q100 (Future 2070-2099 – RCP 8.5) DRAFTPage 334 of 669
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Table 19 Change in Connected Floodplain Areas for 9 Analysis Regions from Historic to Future (median) Conditions.
Region Description
Connected floodplain area (acres)
Q10 Q50 Q100 Q500
Historic Future Change Historic Future Change Historic Future Change Historic Future Change
SLO-1 SLO Cr. below East Fork 456.49 483.01 5.8% 501.64 546.1 8.9% 518.52 570 9.9% 639.41 696.2 8.9%
SLO-2 SLO Cr. from Prefumo to East Fork 120.52 130.44 8.2% 135.11 151.6 12.2% 138.97 155.7 12.0% 165.46 179.8 8.7%
SLO-3 SLO Cr. / Prefumo Cr. confluence area 49.91 94.57 89.5% 119.76 240.7 101.0% 151.44 256.4 69.3% 306.49 365.3 19.2%
SLO-4 SLO Cr. from Stenner confluence to Prado Rd. 123.78 153.36 23.9% 163.81 227 38.6% 182.15 238.7 31.0% 271.45 296.3 9.1%
SLO-5 SLO Cr. upstream of Stenner confluence 43.39 91.53 110.9% 93.98 145.1 54.4% 99.79 149.7 50.0% 195.61 218.1 11.5%
STEN Stenner, Brizziolari, and Old Garden Cr. 43.72 63.4 45.0% 78.73 109.9 39.6% 98.77 129.7 31.3% 152.21 183.8 20.7%
LGNA Laguna Lake area 203.84 226.38 11.1% 260.8 287.1 10.1% 275.39 304 10.4% 367.98 409.5 11.3%
EFK-1 East Fork from SLO Cr. confluence to Buckley Rd. 105.86 124 17.1% 133.24 145.4 9.1% 143.3 154 7.5% - - -
EFK-2 East Fork and tributaries upstream of Buckley Rd. 50.72 79.22 56.2% 93.19 120.3 29.1% 108.72 129.5 19.1% - - -
Source: cbec eco-engineering 2021
Table 20 Change in Connected Floodplain Depths for 9 Analysis Regions from Historic to Future (median) Conditions.
Region Description
Average connected floodplain depth (ft)
Q10 Q50 Q100 Q500
Historic Future Change Historic Future Change Historic Future Change Historic Future Change
SLO-1 SLO Cr. below East Fork 4.1 4.8 17.1% 5.3 6.4 20.8% 5.8 6.8 17.2% 8.3 9.8 18.1%
SLO-2 SLO Cr. from Prefumo to East Fork 2.6 3.3 26.9% 3.8 4.8 26.3% 4.1 5.1 24.4% 6.1 7.6 24.6%
SLO-3 SLO Cr. / Prefumo Cr. confluence area 2 2.2 10.0% 2.3 2.5 8.7% 2.4 2.7 12.5% 3.6 4.9 36.1%
SLO-4 SLO Cr. from Stenner confluence to
Prado Rd. 1.4 1.7 21.4% 1.8 2.1 16.7% 1.9 2.2 15.8% 2.8 3.4 21.4%
SLO-5 SLO Cr. upstream of Stenner confluence 1.7 2.1 23.5% 2.1 2.5 19.0% 2.2 2.6 18.2% 3.4 4.2 23.5%
STEN Stenner, Brizziolari, and Old Garden Cr. 2 2.2 10.0% 2.3 2.7 17.4% 2.4 3 25.0% 3.5 4.3 22.9%
LGNA Laguna Lake area 4.6 5 8.7% 5.1 5.4 5.9% 5.3 5.5 3.8% 6.1 6.4 4.9%
EFK-1 East Fork from SLO Cr. confluence to
Buckley Rd. 4 4.1 2.5% 4.3 4.7 9.3% 4.6 4.8 4.3% - - -
EFK-2 East Fork and tributaries upstream of
Buckley Rd. 2.4 2.3 -4.2% 2.3 2.3 0.0% 2.3 2.4 4.3% - - -
Source: cbec eco-engineering 2021 DRAFTPage 335 of 669
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Key Findings and Policy Considerations
Although annual precipitation is anticipated to increase in the City and the larger central coast region, California’s
climate oscillates between extremely dry and extremely wet periods with annual precipitation varying widely from
year to year. These oscillations between extremely dry and extremely wet periods are anticipated to become more
severe with rapid shifts from dry to wet periods known as “whiplash events” (Swain et al. 2016). These types of
events are estimated to increase by approximately 100 percent in southern California, with increases in frequency
occurring largely after 2050 (Swain et al. 2016).
Based on California’s location next to the Pacific Ocean, the state is exposed to the atmospheric river (AR)
phenomenon, a narrow corridor of concentrated moisture in the atmosphere. The presence of the AR contributes
to the frequency of “wet years” in the state, when there is an above-average number of AR storms and above-
average annual precipitation. While research indicates that the frequency of large storms events does increase in
these wet years, the most severe flooding from ARs may not be in wet years (Swain et al. 2018). The largest flooding
impacts are caused by persistent storm sequences on sub-seasonal timescales (i.e., short time periods, typically 2
weeks to 3 months), which bring a significant fraction of annual average precipitation over a brief period. Based on
current climate modeling, the frequency of these large storm sequences over short timeframes is projected to
increase noticeably under a future high emissions scenario. It is estimated that a storm similar in magnitude to the
Great Flood events is more likely than not to occur at least once between 2018 and 2060 (Swain et al. 2018).
For very large precipitation events, the capacity of the watershed to absorb incoming rainfall can be quickly
exceeded, causing large increases in stream flow within the system. By as early as 2070 under a high future
emissions scenario, peak flow rates in the San Luis Obispo Creek watershed are projected to increase, on average,
from 17 percent to 38 percent depending on the size of the storm event. By this period, for the storm event with a
50 percent chance of occurring in any given year (2-year storm event), the median peak stream flow is projected to
increase by 28 percent with a small likelihood (90th percentile) of stream flow increasing by 51 percent.
By as early as 2070 under a high future emissions scenario , for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek confluence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infrastructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confluence
FLOODING AND THE BUILT ENVIRONMENT
Key Flood Impact Areas
Areas with the greatest increases in connected floodplain
inundation for the 10-year through 100-year events included SLO
Creek upstream of the Stenner confluence (SLO-5, including parts
of downtown SLO), the SLO Creek – Prefumo Creek confluence
area (SLO-3, including SLO Creek from Prado Road to the
Prefumo Creek confluence and Prefumo Creek below Madonna
Road), East Fork and its tributaries upstream of Buckley Road (EFK-
2), and Stenner, Brizziolari, and Old Garden Creeks (STEN). In the
modeling, these areas tended to have greater expanses of floodplain areas, such as the SLO Creek – Prefumo Creek
confluence area, or limiting infrastructure, as is the case with the undercity culvert through downtown. Areas that were
more confined by topography, such as SLO Creek below East Fork (SLO-1), experienced smaller increases in area, as
shown in Table 19. Average connected floodplain depth, on the other hand, can be slightly more difficult to assess
because it was calculated as the average of wet areas with greater than 0.1 ft of depth. Therefore, the average depth can
decrease even if the inundated area increases with large areas of shallow depth flooding in a future scenario that are
currently inundated under existing flood conditions. Percent increases in depth for the region containing parts of DRAFTPage 336 of 669
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downtown were on the order of 18 to 23.5 percent across the range of flood events, with an increase in average
floodplain depth for the 100-yr event of 0.4 ft increasing to 2.2 to 2.6 ft, as shown in Table 20.
Figures 32 through Figure 36 show inundation depth for the 10-year and 100-year events for the San Luis Obispo
Creek – Stenner Creek confluence area, including a portion of downtown. For the 10 -year event, increases in flooding
along Old Garden Creek are apparent, along with portions of downtown and at the confluence of the two creeks
(Figures 32 and 33). Some of the flooding within the downtown area from the 10 -year event may be due to the
model generally over-predicting flood levels (Questa Engineering Corporation 2003). For the 100 -year event,
dramatic increases are observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek
confluence and within the downtown area. In both cases, flooding is exacerbated by the capacity of the existing
infrastructure to manage historic flooding events. For Stenner Creek, the water level passing underneath Highway 101
reaches up to the bottom of the bridge and begins to exceed the flow capacity of the structure. Similarly, the
undercity culvert within downtown has a capacity of abou t a 15-year event under historic conditions (Questa
Engineering Corporation 2003). For larger events, such as the 100-year, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera and
Marsh Street corridor towards the Stenner Creek confluence , as shown in Figures 35 and 36.
Figures 37 through 39 show similar results for the San Luis Obispo – Prefumo Creek confluence area. Within these
regions of the City, large expanses of relatively flat, low-lying land persist between and along the two creeks. Flood
waters can spill into these areas by crossing Highway 101 near Madonna Road from San Luis Obispo Creek or by
escaping the creek channels in the confluence area and causing backwater conditions for upstream reaches. The City
undertakes regular maintenance activities within Prefumo Creek from Laguna Lake to Los Osos Valley Road to
manage flood risk in this area. The southern end of the Los Osos Valley Road area north of Highway 101 is particularly
vulnerable. For the 100-year event, large areas of agricultural land between Prefumo and San Luis Obispo Creeks may
become inundated under future conditions , as shown in Figures 39 and 40.
Ultimately, changes in flood risk need to be understood using multiple metrics. The flood maps and summary tables of
changes in inundated area and average depth are important for understanding how different levels of risk are present
within different areas of the City. These varying levels of risk may be due to the topography of the landscape and
channels, but they may also be affected by infrastructure. In either case, changes in flood risk do not necessarily vary in
the same way as changes in stream flow, which in turn may not directly mirror changes in precipitation, reinforcing the
importance of conducting hydrologic and hydraulic modeling. For the 100-year event, there was a 38 percent increase in
stream flow for the median future scenario compared to historical conditions, as show in Table 19. However, this does
not necessarily translate to flooding being 38 percent worse. The reach of San Luis Obispo Creek upstream of the
Stenner Creek confluence and the San Luis Obispo – Prefumo Creek confluence areas experienced increases in
inundated floodplain acreage of 50 and 69.3 percent, respectively, as shown in Table 19, while average floodplain depths
increased from 2.2-2.4 ft to 2.6-2.7 ft, as shown in Table 20. Further, it is helpful to think about flood risk statistically. As
shown in Table 19, the future 50-year event has similar levels of inundation to the historic 100-year event. This means
that with a 37 percent increase in flow (from the historic 50-year event, Table 19), the level of inundation from an event
that used to occur about once every 100-years would be experienced twice as frequently.
IMPACT ANALYSIS OF THE TRANSPORTATION SYSTEM
Using the climate-informed flood analysis discusses above, a high-level impact analysis on the City’s transportation
system was conducted, focusing on the facilities identified through community feedback including impacts to the
transit network, the City’s open space trails network, and the viability of the City’s roadway network and evacuation
routes during emergency evacuation scenarios related to flooding . The analysis was conducted using the 10-year,
100-year, and 500-year flood mapping layers, assessing how these flood events would affect the City’s transportation
system. Figure 41 overlays the flood zones on the transportation network and is discussed below. DRAFTPage 337 of 669
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Source: Fehr and Peers 2021
Figure 41 City Transportation Assets Impacted by Flooding DRAFTPage 338 of 669
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Roadways
The City’s roadway network is identified as local streets, arterials, freeway, and bicycle and pedestrian facilities ,
providing circulation within the City as well as roadway network connections to the other areas in the County. The
extent of roadway network impacts on the City is dependent on the varying size of the storm even ts analyzed. Figure
41 illustrates those potential impacts adjacent to San Luis Obispo Creek along US 101, specifically at the Madonna
Road interchange and the Los Osos Valley Road interchange during the 10-year,100-year, 500-year storm events. The
greatest area of impact to local roads during these events would be areas just south of San Luis Obispo Creek
through the downtown area with the farthest extent along Santa Barbara Street as far South as Lef f Street occurring
during the 100-year storm event. Moving away from the downtown area , flooding occurs to the east of the SLO Creek
between US 101 and Higuera Street between the US 101 and Broad Street interchange and the US 101 and Madonna
Road interchange. During the 100-year and 500-year storm events, flooding would likely occur along US 101 in the
northbound lanes at the Prado Road on and off ramp. Flooding would also occur along Prado Road near San Luis
Obispo Creek. The flood modeling analysis also identifies the Chorro Street undercrossing at US 101 would be
impacted by the 10-year, 100-year, and 500-year floods. These same flood zones would also result in potential
impacts between Foothill Boulevard and US 101 between Broad Street and State Route 1.
Transit
Alongside the roadway network, future flood impacts would also affect transit operations and assets. Extensive
flooding has the potential to limit transit service, thus eliminating transport options for populations in the City
dependent on transit. Table 21 illustrates the number of impacted transit stops and percent o f stops in the total
network that would be affected, categorized by each size storm event and transit provider . The rail network in the
City would not be affected during the potential flood events. The exact location of the transit stops impacted by the
10-year, 100-year, and 500-year storm events are visualized in Figure 42.
Table 21 Transit Stops Impacted by Storm Event
Transit Agency Total Number
of Stops 10-year 100-year 500-year
SLO Transit 161 7 - 11 % 16 - 26 % 35 - 57%
San Luis Obispo Regional Transit Authority (RTA) 26 2- 8% 3 - 12% 6 – 23%
Source: Fehr and Peers 2021
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Figure 42 Transit Assets Impacted by Flooding DRAFTPage 340 of 669
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Recreation Trails and Existing Bicycle Transportation
Flood related impacts on the City’s bicycle and recreational trails network were similar to impacts on the roadway
network. Bicycle infrastructure through the downtown area south of the San Luis Obispo creek are likely to be affected
by future flood impacts. As shown in Figure 42, the following recreational trail are also likely to be impacted by flooding.
Bob Jones Trail
Johnson Ranch
Madonna Inn Bike Trail
Laguna Lake Upper Loop Trail
The areas of highest concern are located in the downtown area South of the San Luis Obispo Creek, the Chorro
Street undercrossing, and around the Los Osos Valley Road interchange at US 101. It is important to define transit
options for the limited number of stops impacted by flooding during flood events. If applicable , mitigation and
engineering can remedy the flooding sources, transit would likely be unimpacted. Alternatively, the use of bicycle
transit to transport populations without adequate mobility resources should be considered for evacuation plans.
Key Findings and Policy Considerations
From the results of the climate-informed flood modeling, areas with the greatest increases in connected
floodplain inundation for the 10-year through 100-year events included SLO Creek upstream of the Stenner
confluence (including parts of downtown SLO), the SLO Creek – Prefumo Creek confluence area, East Fork and its
tributaries upstream of Buckley Road, and Stenner, Brizziolari, and Old Garden Creeks. In the modeling, these
areas tended to have greater expanses of floodplain areas, such as the SLO Creek – Prefumo Creek confluence
area, or limiting infrastructure, as is the case with the undercity culvert through downtown.
By as early as 2070 under a high future emissions scenario , for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek confluence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infrastructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confluence .
Near the San Luis Obispo – Prefumo Creek confluence area near Higuera Street and Madonna Road, large
expanses of relatively flat, low-lying land persist between and along the two creeks. During larger storm events
(50-year and 100-year storms), flood waters can spill into these areas by crossing Highw ay 101 near Madonna
Road from San Luis Obispo Creek or by escaping the creek channels in the confluence area and causing
backwater conditions for upstream reaches.
The greatest area of impact to local roads during large storm events (100-year storm) would be areas just south
of San Luis Obispo Creek through the downtown area with the farthest extent along Santa Barbara Street as far
South as Leff Street. The Chorro Street undercrossing at US 101 would be impacted by the 10 -year, 100-year, and
500-year floods.
Extensive flooding from larger storm events also has the potential to limit transit service, thus eliminating
transport options for populations in the City dependent on transit, with between 16 to 26 percent of SLO Transit
stops being affected depending on the storm size. DRAFTPage 341 of 669
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FLOODING AND COMMUNITY RESILIENCE
Evacuation Routes and Emergency Communications
As part of this analysis, an assessment of the underlying hazards
and appropriate access to gateways (e.g., major ingress and
egress points in and out of the City) and evacuation centers has
been completed to facilitate the development of reliable
accurate communication for emergency needs and evacuations.
With the projected increases in the frequency and severity
wildfire events, and large storm events expected to occur due to
climate change, new methods of administering evacuation
information have been evolving. Iterative development and
updating of the emergency preparedness plan are critical and
should identify a communication plan for reside nts and visitors on how to evacuate in case of an emergency. To
support the communication components of evacuation planning, a detailed analysis of access to City gateways and
evacuation centers is provided below to assist in identifying areas where infras tructure improvements would benefit
future evacuation planning.
Flood Impacts and Low-Vehicle Access
Using the US Census block group data, Figure 43 illustrates census blocks in the City with the percentage of occupied
housing units without access to a vehicle. According to the Census data, in the City, approximately 8 percent of
occupied housing units do not have access to at least one vehicle. However, the range for all the block groups within
the City is 0 to 21.4 percent. Certain block groups have highe r numbers of households without vehicles available,
therefore specific consideration for services to access evacuation centers or assistance of these populations to leave
the City during an emergency should be prepared. The City’s Car Less Collection Point s layer is included and shows
some correspondence to the census block groups with a higher portion of households without vehicles. These
populations tend to primarily be located adjacent to US 101 and the San Luis Obispo Creek.
Gateway and Evacuation Center Access Assessment
This section includes a scenario level review of residential access to City gateways and evacuation centers from the
centroids of census block groups for the City. This assessment is based on an evolving methodology created for
evacuation studies consistent with Assembly Bill (AB) 747 and SB 99, which requires an assessment of residential
evacuation routes during the City’s next Safety Element update. The analysis included here is not a comprehensive
assessment of the City’s evacuation routes but provides supporting resources for an evacuation study consistent with
AB 747 and SB 99.
This document is intended to provide an assessment of roadway access under the described flood scenarios but
should not be considered a full evacuation plan. Additionally, flooding patterns are, to a certain degree,
unpredictable as is individual behavior related to evacuation events. As such, this assessment is intended to provide
the City with a broad “planning level” assessment of the access of the transpo rtation system during flood events; it
does not provide guarantees as to the adequacy of the transportation system nor can it guarantee that the findings
are applicable to any or all situations. DRAFTPage 342 of 669
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Source: Fehr and Peers 2021
Figure 43 Census Block Groups with No Vehicles per occupied housing unit DRAFTPage 343 of 669
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Evacuation Route Analysis Methodology
This analysis was developed in ArcGIS using network analyst as a variation on an evacuation scenario tool including
the centroid of census block groups, and the flood zone layers provided by the City. The analysis calculates the
closest route by distance from the centroid of a block group to the gateway outside of the City or the evacuation
center nearest the centroids. As it relates to this study, gateways are defined as major arterials and highways located
at the City limit. The gateways used in this analysis include the following roads, US 101 Northbound and Southbound
at the respective City limits, State Route (SR) 227 or Broad Street, Orcutt Road, South Higuera Street, SR 1, and Los
Osos Valley Road. The gateways matched the evacuation routes the City designated and communicates thr ough the
fire evacuation plan (City of San Luis Obispo n.d.).
Census block groups are statistical divisions of census tracts, are generally defined to contain between 600 and 3,000
people. In this analysis, the centroids of these block groups were calculated and joined with specific demographic
data, citing whether vehicles were available for occupied housing units. This was done to visualize an even
distribution of population and access throughout the City. When required the centroid locations were adjust ed to
reflect street network connectivity. The block group centroids were used to begin the travel analysis to both City
gateways and evacuation centers. Flood zone for the analysis is defined by FEMA as the area that will be inundated
by the 100-year flood event and 500-year flood event as discussed previously on section 2.5.1. CBEC generated the
10-, 100-, and 500-year flood waters data used in our transportation models.
Evacuation Route Analysis Results
For this analysis, access to the City’s gateways and evacuations centers were assessed without any flooding as a
baseline condition. Access to these locations was then analyzed for the 10-year, 100-year, 500-year flood events to
identify transportation route and asset vulnerabilities under each of these e vents. The following figures represent a
visual representation of the analysis for the defined year flood events discussed above.
As shown in Figures 44 through 49, access from census block group centroids to City gateways for the 10-year, 100-
year, and 500-year flood events are relatively similar as the locations of flooding occur in generally the same location
under various storm events. As shown, under each flood event some routes within the City’s street network are
compromised, in which case, an alternative route is created to analyze route diversions as a result of flood impac ts. In
many cases, this may result in a longer distance to be travelled to access the gateway or evacuation center under
different flood scenarios.
For all flooding events (i.e., 100-year and 500-year flood events), access to the Southern Gateway of US 101 is
compromised due to potential flooding of US 101 and Los Osos Valley Road. However, all centroids under these
scenarios are able to access at least one alternative City gateway, which means no portions of the City would be
closed off due to roadway network flooding. The 100-year flood scenario shows impacted access to many
neighborhoods throughout the City, resulting in one Block Group centroid being cut off to both a gateway and
evacuation center. This is in the area North of US 101 and West of SR 1.
The 500-year flood scenario shows an inability of four census block group centroids to access either the City
gateways or evacuation centers as they experience extensive flooding, isolating their ability to connect to a route.
These centroids are located within the 500-year flood layer, thus preventing a routed network to be completed. The
depth of the flooding is available however further analysis identifying the height of the infrastructure would be
required to understand the extent of actual access from neighborhoods to gateways and evacuation centers.
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Figure 44 Access from Census Block Group Centroid to City Gateways DRAFTPage 345 of 669
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Source: Fehr and Peers 2021
Figure 45 Access from Census Block Group Centroid to City Evacuation Center s DRAFTPage 346 of 669
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Source: Fehr and Peers 2021
Figure 46 Access from Census Block Group Centroid to City Gateways with 100 Year Flood DRAFTPage 347 of 669
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Source: Fehr and Peers 2021
Figure 47 Access from Census Block Group Centroid to City Evacuation Centers with 100 Year Flood DRAFTPage 348 of 669
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Source: Fehr and Peers 2021
Figure 48 Access from Census Block Group Centroid to City Gateways with 500 Year Flood DRAFTPage 349 of 669
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Figure 49 Access from Census Block Group Centroid to City Evacuation Centers with 500 Year Flood
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Table 22 shows the difference between the baseline conditions access and each flood scenario.
Table 22 Flood Year and Longest Distances to City Gateways and Evacuation Centers
Destination Baseline – No flood 100 year* 500 year**
Gateways 3.5 miles 4 miles 4 miles
Evacuation Centers 3 miles 5 miles 5 miles
Note: * = Signifies 1 Block Group centroid was cut off from both gateways and evacuation centers. ** - Signifies 4 Block Group centroids were cut
off from both gateways and evacuation centers.
Source: Fehr and Peers 2021
Flooding and Vulnerable Populations
Several populations within the City may experience disproportionate impacts from flooding due to social
characteristics and environmental burdens. Disadvantaged communities are more likely to be located in flood prone
areas, may be linguistically isolated and unable to interpret and respond to warning messages and evacuation
notices, and have limited mobility. As shown in Figure 50, the disadvantaged communities in the central portion of
the City are located within the 100- and 500-year flood zones.
Lack of vehicle access is another social factor that may lead to increased vulnerability to flood events. Using the US
Census block group data, Figure 43 illustrates census blocks in the City with the percentage of occupied housing
units without access to a vehicle. According to the Census data, in the City, approximately 8 percent of occupied
housing units do not have access to at least one vehicle. However, the range for all the bloc k groups within the City is
0 to 21.4 percent. Certain block groups have higher numbers of households without vehicles available, therefore
specific consideration for services to access evacuation centers or assistance of these populations to leave the Cit y
during an emergency should be prepared. The City’s Car Less Collection Points layer is included and shows some
correspondence to the census block groups with a higher portion of households without vehicles. These populations
tend to primarily be located adjacent to US 101 and the San Luis Obispo Creek.
A key environmental burden is the presence of cleanup sites, which are sites monitored by the Department of Toxic
Substances Control that are contaminated with harmful chemicals . Flooding could release hazardous and/or toxic
materials if cleanup sites are inundated, exposing nearby communities to public health impacts. CalEnviroScreen 4.0
includes a cleanup sites indicator that considers the number and types of cleanup sites in or near each census tracts,
as well as how close the sites are to where people may live. As shown in Figure 52, there are several cleanup sites
located within the 100-year flood zone. There are also census tracts in the City within the City’s 100- and 500-year
flood zones that score in the 70th percentile and higher for clean up site exposure, based on the weighted score of
potential pollution exposure used in CalEnviroScreen. This means these census tracts have higher potential exposure
than 70 percent of all census tracts in the State , indicating that there is a potential for residents in these areas to be
exposed to contaminants in the event of a flood.
As show in Figure 50, the area West of South Higuera Street (Census Tract 115.01) is located almost entirely within the
100- and 500-year flood plain which is anticipated to expand in the future due to climate change. This area is
particularly vulnerable with high percentage of elderly residents (17 percent) as we ll as a high percent of disabled
residents (15 precent), presenting potential challenges during emergency evacuation events. Figure 51 includes areas
in the City with low-income households (i.e., households earning 80 percent less of the County median inco me) as
well as the 100- and 500-year flood plain. During larger flood events, these households are at a potential
disadvantage during the post-disaster recovery period with less financial or other resources available for recovery
efforts. Additionally, as show in Figure 53 there is significant overlap between the location of homeless encampments
throughout the City and the location of the existing and future 100 - and 500-year flood plains. Shelters and
encampments built by unhoused individuals are often dev eloped in or near flood plains, placing these populations at
increased risk during flood events, particularly in areas with lower levels of access to transportation in emergency
events. Increased heavy precipitation and flooding will disproportionately imp act homeless populations because they
occupy marginal areas, they are less able to transport themselves out of flood areas and they are more likely to suffer
sequelae (i.e., exacerbation of existing health conditions) from such disasters. (Ramin and Svoboda 2009). DRAFTPage 351 of 669
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Sources: Data received from SLOCOG in 2021 and from CBEC Engineering in 2020, and downloaded from City of San Luis Obispo in 2020 and
County of San Luis Obispo in 2020
Figure 50 Disadvantaged Communities and 100-year and 500-year Flood Plains DRAFTPage 352 of 669
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Sources: Data received from SLOCOG in 2021 and from CBEC Engineering in 2020, and downloaded from City of San Luis Obispo in 2020 and
County of San Luis Obispo in 2020
Figure 51 Low-Income Areas and Flood Plains in the CityDRAFT
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Sources: Data downloaded from OEHHA in 2021 and received from CBEC Engineering in 2020, and downloaded from City of San Luis Obispo in
2020 and County of San Luis Obispo in 2020
Figure 52 Hazardous Material Clean Up Sites and Flood Plains in the City DRAFTPage 354 of 669
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Sources: Data downloaded from US Census in 2019, City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 53 Location and Relative Density of Homeless Encampments in the City of San Luis Obispo DRAFTPage 355 of 669
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Community Flooding Concerns
As part of the community priorities survey, when participants were asked to report on their level of concern for
flooding, as shown in Figure 54, 70 percent of respondents indicated that they were “Somewhat” or “Very Concerned”
about the issue. When asked about whether they had been impacted by flooding in the last 1-3 years, only 15 percent
of respondents indicated “Somewhat” or “Very”. Additionally, individuals with a household income of less than
$50,000 and individuals aged 18 to 24 reported the highest level of concern for flooding. Individuals who identify as
all other races and ethnicities, compared to individuals who identify as white or caucasian, also expressed a higher
level of concern for flooding (i.e., 36 percent v. 24 percent, respectively).
Sources: Resilient SLO Community Priorities Survey
Figure 54 City Resident’s Flooding Concern and Impact
Key Findings and Policy Considerations
For all flooding events (i.e., 100-year and 500-year flood events), access to the Southern Gateway of US 101 is
compromised due to potential flooding of US 101 and Los Osos Valley Road. However, all centroids under these
scenarios are able to access at least one alternative City gateway, which means no portions of the C ity would be
closed off due to roadway network flooding.
The 500-year flood scenario, illustrated in Figure 42, shows an inability of four census block groups to access
either the City gateways or evacuation centers as they experience extensive flooding, i solating their ability to
connect to a route.
There is significant overlap between areas in the City where disadvantaged communities have been identified
and the 100- and 500-year floodplain, resulting in potentially disproportionate impacts on these popul ations in
the City during large storm events.
The area West of South Higuera Street (Census Tract 115.01) is located almost entirely within the 100 - and 500-
year flood plain which is anticipated to expand in the future due to climate change. This area is particularly
vulnerable with high percentage of elderly residents (17 percent) as well as a high percent of disabled residents
(15 precent), presenting potential challenges during emergency evacuation events.
Increased heavy precipitation and flooding will disproportionately impact homeless populations because they
occupy marginal areas, they are less able to transport themselves out of flood areas during these events.
31%
44%
26%
85%
13%
2%
0%
20%
40%
60%
80%
100%
Not at all Somewhat VeryPercent of RespondentsLevel of Concern
FLOODING CONCERN & IMPACT
Which of the following climate change impacts are you concerned about [Flooding]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Flooding]?
Total Responses = 328 DRAFTPage 356 of 669
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2.6.3 Adaptive Capacity for Precipitation and Flooding Impacts
Adaptive Capacity Rating: Medium/Low
Given its geographical location and the presence of several waterways within its boundaries, the City has been subject
to a number of significant flooding events in the past. As a result, the City has taken considerable steps to analyze
potential impacts from larger flooding events and mitigate the effects of these events when they do occur. Annex G
of the Multi-Jurisdictional Hazard Mitigation Plan (San Luis Obispo County 2019b) includes a thorough analysis of
flooding impacts from the 100 -year and 500-year storm events, assessing the critical facilities that would be affected
by these storms. Annex G also includes a capability assessment that provides an inventory of existing regulatory tools
(e.g., ordinances, plans), personnel resources, financial resources (e.g., grants, fees), and partnerships that are
currently used or could be used in the future to implement hazard mitigation activities.
Although the City has some authority under the City’s Municipal Code for emergency removal of vegetation and
other debris, general maintenance of the creeks falls upon the owners of property adjacent to the creek. Additionally,
the creek corridor is highly confined in areas, particularly through downtown, making projects such as channel
widening infeasible. Following the 1973 flood, the George S. Nolte & Associates study, completed in 1977, identified
proposed flood control projects, but few were adopted because of the environmental effects associated with channel
widening and other alternatives (Questa Engineering Corporation 2 003). Several areas of the City, including
downtown areas along San Luis Obispo Creek, the intersection of U.S. 101 and Los Osos Valley Road, the Johnson
Avenue railroad underpass, and areas surrounding Laguna Lake, have been at a high risk for frequent fl ooding (City
of San Luis Obispo 2011). To address these issues, large projects have been proposed to manage flood risk in the
increasingly urbanized City. One such project is a high-flow bypass channel for the confluence of Laguna Lake and
(the upstream portion) Prefumo Creek. An additional proposed project is the Mid-Higuera Bypass Project, which
would increase conveyance capacity of San Luis Obispo Creek between Marsh Street and Madonna Road. This area,
downstream of the confluence of Stenner and San Luis Obispo Creeks, has flooded and received extensive damage in
some of the historical floods previously mentioned. The planned removal of sediment and Arundo stands from San
Luis Obispo Creek south of Los Osos Valley Road will also serve to reduce local flood risk.
In 2003, the City developed and adopted its current Waterway Management Plan in coordination with the San Luis
Obispo County Flood Control and Water Conservation Distr ict Zone 9 Advisory Committee (Questa Engineering
Corporation 2003). The purpose of this plan is to adopt an approach and schematic plans to address flooding,
erosion, water quality, and ecological issues in the San Luis Obispo Creek Watershed that can be implemented with
approval from various regulatory agencies.
The plan includes five key components to achieve the plan’s objective. These include the following:
Stream Maintenance and Management Program and guidance document for routine stream maintenance;
New Drainage Design Manual for storm water, flood control, and bank repair design;
Flood Management Plan that outlines the conceptual flood control alternatives;
Bank Stabilization Program that provides a management framework and conceptual plans for addr essing current
and future bank instability problem areas; and
Habitat Enhancement and Restoration Program that provides a conceptual plan and framework for stream
resource enhancement, restoration, and protection.
The City is currently enrolled in the State’s mandated National Pollution Discharge Elimination System Program which
includes requirements to help manage urban stormwater. One of the Best Management Practices (BMP) included in
these requirements are practices to address sediment and debris in the storm drain system so the material/pollutants
can be removed, and the capacity can be restored to system and allow it to function as designed. The City has
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system. In the first 5 years of this BMP, over 80 percent of the storm drain system was restored and was able to convey
water from the streets to the creeks and drainages under full capacity (City of San Luis Obispo, Otte pers. comm., 2021).
In current practice, the stormwater management system for the City is designed to manage small and large storm
events based on characteristics of rainfall specific to the region from observed historical data. These characteristics
are described using the intensity, duration, frequency (IDF) curves of historic storm events. These IDF curves are used
to design various components of urban drainage systems including pipes, culverts, and waterway channels. Given
that the City’s existing water management system has been designed and built to manage historic precipitation
levels, this infrastructure can be difficult to retrofit and adjust to manage larger storm events, limiting the City’s
options for managing more intense storm events due to climate change (CEC 2018).
For the reasons discussed above , the adaptive capacity ranking for increased precipitation and flooding is
medium/low.
2.6.4 Vulnerability Summary
Under existing conditions, without the influence of climate change, the City has experienced larger scale flood events
in the past. As discussed in Sections 2.5.1 and 2.5.2, the City is particularly vulnerable to increased future flooding risk
due to climate change with the intensity and frequency of large storm events increasing significantly by the end of
the century. Because the City’s existing stormwater management and flood management infrastructure have been
designed and built to manage historic flood events, as the size of large storm events increases, the City’s existing
infrastructure will be compromised in its ability to successfully manage these events. Flooding impacts on the City’s
physical infrastructure could result in secondary impacts including interruptions to the City’s evacuation routes as
discussed in Section 2.5.2, impacts to life and property for homes and businesses located in existing floodplains and
new more extensive floodplains, faster degradation of infrastructure, and economic impacts during post -disaster
recovery. Based on the analysis of various impacts discussed above, the City’s potential impact scoring is High (3).
Precipitation and flooding impacts that are unique to the City and should be given increased consideration during
the adaptation strategy development process are discussed below.
Natural Systems Findings
Although annual precipitation is anticipated to increase in the City and the larger central coast region, California’s
climate oscillates between extremely dry and extremely wet periods with annual precipitation varying widely from
year to year. These oscillations between extremely dry and extremely wet periods are anticipated to become more
severe with rapid shifts from dry to wet periods known as “whiplash events” (Swain et al. 2016). These types of
events are estimated to increase by approximately 100 percent in southern California, with increases in frequency
occurring largely after 2050 (Swain et al. 2016).
Based on California’s location next to the Pacific Ocean, the state is exposed to the atmospheric river (AR)
phenomenon, a narrow corridor of concentrated moisture in the atmosphere. The presence of the AR contributes
to the frequency of “wet years” in the state, when there is an above-average number of AR storms and above-
average annual precipitation. While research indicates that the frequency of large storms events does increase in
these wet years, the most severe flooding from ARs may not be in wet years (Swain et al. 2018). The largest flooding
impacts are caused by persistent storm sequences on sub-seasonal timescales (i.e., short time periods, typically 2
weeks to 3 months), which bring a significant fraction of annual average precipitation over a brief period. Based on
current climate modeling, the frequency of these large storm sequences over short timeframes is projected to
increase noticeably under a future high emissions scenario. It is estimated that a storm similar in magnitude to the
Great Flood events is more likely than not to occur at least once between 2018 and 2060 (Swain et al. 2018).
For very large precipitation events, the capacity of the watershed to absorb incoming rainfall can be quickly
exceeded, causing large increases in stream flow within the system. By as early as 2070 under a high future
emissions scenario, peak flow rates in the San Luis Obispo Creek watershed are projected to increase, on average,
from 17 percent to 38 percent depending on the size of the storm event. By this period, for the storm event with a DRAFTPage 358 of 669
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50 percent chance of occurring in any given year (2-year storm event), the median peak stream flow is projected to
increase by 28 percent with a small likelihood (90th percentile) of stream flow increasing by 51 percent.
Built Environment Findings
By as early as 2070 under a high future emissions scenario , for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek confluence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infrastructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the chan nel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confluence
From the results of the climate-informed flood modeling, areas with the greatest increases in connected
floodplain inundation for the 10-year through 100-year events included SLO Creek upstream of the Stenner
confluence (including parts of downtown SLO), the SLO Creek – Prefumo Creek confluence area, East Fork and its
tributaries upstream of Buckley Road, and Stenner, Brizziolari, and Old Garden Creeks. In the modeling, these
areas tended to have greater expanses of floodplain areas, such as the SLO Creek – Prefumo Creek confluence
area, or limiting infrastructure, as is the case with the undercity culvert through downtown.
By as early as 2070 under a high future emissions scenario , for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek conflu ence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infrastructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confluence .
Near the San Luis Obispo – Prefumo Creek confluence area near Higuera Street and Madonna Road, la rge
expanses of relatively flat, low-lying land persist between and along the two creeks. During larger storm events
(50-year and 100-year storms), flood waters can spill into these areas by crossing Highway 101 near Madonna
Road from San Luis Obispo Creek or by escaping the creek channels in the confluence area and causing
backwater conditions for upstream reaches.
The greatest area of impact to local roads during large storm events (100-year storm) would be areas just south
of San Luis Obispo Creek through the downtown area with the farthest extent along Santa Barbara Street as far
South as Leff Street. The Chorro Street undercrossing at US 101 would be impacted by the 10 -year, 100-year, and
500-year floods.
Extensive flooding from larger storm events also has the potential to limit transit service, thus eliminating
transport options for populations in the City dependent on transit, with between 16 to 26 percent of SLO Transit
stops being affected depending on the storm size.
Community Resilience Findings
For all flooding events (i.e., 100-year and 500-year flood events), access to the Southern Gateway of US 101 is
compromised due to potential flooding of US 101 and Los Osos Valley Road. However, all centroids under these
scenarios are able to access at least one alternative City gateway, which means no portions of the City would be
closed off due to roadway network flooding.
The 500-year flood scenario, illustrated in Figure 42, shows an inability of four census block groups to access
either the City gateways or evacuation centers as they experience extensive flooding, isolating their ability to
connect to a route.
There is significant overlap between areas in the City where disadvantaged communities have been identified
and the 100- and 500-year floodplain, resulting in potentially disproportionate impacts on these populations in
the City during large storm events. DRAFTPage 359 of 669
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2-110 Climate Change Hazards and Vulnerability Report
The area West of South Higuera Street (Census Tract 115.01) is located almost entirely within the 100 - and 500-
year flood plain which is antici pated to expand in the future due to climate change. This area is particularly
vulnerable with high percentage of elderly residents (17 percent) as well as a high percent of disabled residents
(15 precent), presenting potential challenges during emergency evacuation events.
Increased heavy precipitation and flooding will disproportionately impact homeless populations because they
occupy marginal areas, they are less able to transport themselves out of flood areas during these events.
Adaptive Capacity: Medium/Low (2.5)
Potential Impact: High (3)
Vulnerability Score: 4.5
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3 VULNERABILITY SCORING SUMMARY
As described in this Report, the City’s vulnerability to each identified impact has been assessed based on the
magnitude of risk to and potential impacts on Natural Systems, the Built Environment, and Community Resilience .
Importantly, the assessment also considers the City’s current adaptive capacity to mitigate these climate-related
hazards when impacts do occur. Table 23 presents a list of important plans, resources, and documents that already
exist and are being used to help mitigate risk from these climate -related hazards.
Table 23 Summary of Existing Plans and Reports
Plan or Report
Climate Change Hazard
Increased
Temperatures and
Extreme Heat
Increased
Wildfire Risk
Increased
Precipitation and
Flooding
Drought and Water
Supply
California’s Fourth Climate Change Assessment, Central Coast
Region Report ✓ ✓ ✓ ✓
City Local Hazard Mitigation Plan Annex ✓ ✓ ✓
City General Plan ✓ ✓ ✓
City Emergency Operations Plan ✓ ✓
Waterway Management Plan ✓
City Community Wildfire Protection Plan ✓
City Urban Water Management Plan ✓
City Open Space Vegetation Management Plan ✓
Source: Ascent Environmental 2021
Based on the ratings of potential impacts and adaptive capacity, an overall vulnerability score was determined for
each climate change effect. This scoring process can help the City understand which effects pose the greatest threats
and should be prioritized in future planning e fforts.
As shown in Table 24, increased extreme precipitation and flooding is assigned a vulnerability rating of 4.5 and has
the highest vulnerability score. Increases in temperature and extreme heat as well as increase wildfire risk are both
given a vulnerability score of 4. Although ranked slightly lower, t hese climate change effects are also likely to have
significant impacts on the City in the near-term and midterm periods. Although a variety of adaptive efforts related to
both climate change effects are in place and underway, the magnitude of the impacts posed by these hazards
contributes to high vulnerability for the City and its populations . Finally, increased long-term drought is characterized
as having a vulnerability rating of 3.5. This climate change effect is currently being addressed adequately based on
existing conditions, but additional adaptation and resilience planning will still be required in the future to mitigate
impacts and protect the City.
Table 24 Summary of Vulnerability Scoring
Climate Change Effect Vulnerability Score
Adaptive Capacity Potential Impact Vulnerability
Increased Extreme Precipitation and Flooding Medium/Low High 4.5
Increased Temperatures and Extreme Heat Low Medium 4
Increased Wildfire Medium High 4
Long-Term Drought High Medium 3.5
Source: Ascent Environmental in 2021 DRAFTPage 363 of 669
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3-2 Climate Change Hazards and Vulnerability Report
Provided below is a summary of impacts that are unique to the City for each of the four climate-related hazards and
should be given increased consideration during the adaptation strategy development process are discussed below.
TEMPERATURES AND EXTREME HEAT KEY FINDINGS
Natural System Findings
Changes in temperature and extreme heat are likely to have negative impacts on the City’s tree canopy with
some tree species no longer suitable for future minimum and maximum temperatures. Any future policies
focused on improving the City’s tree canopy or green spaces to mitigate the urban heat island effect should
carefully consider what plant and tree species will be suitable for future climate conditions.
Climate change is projected to encourage the spread of invasive species in the City’s open spaces, affecting
coastal sage scrub habitats as well as the City’s oak species from Sudden Oak Death.
Regional impacts on agriculture and viticulture industries from shifting temperatures have the potential to impact
the City via decreases in wine and vineyard-based tourism, with the City relying heavily on revenue and
employment opportunities in these industries. Resilience strategies focused on economic impacts should
consider potential impacts on viticulture vineyard -based tourism and potential diversification of the City’s tax
revenue sources and employment industries.
Built Environment Findings
The Margarita Avenue Neighborhood (Census Tract 111.03) include s population characteristics that make this area
particularly vulnerable to extreme heat and is located in an area of the City with increased urban heat island
severity. Resilience strategies that mitigate impacts of the urban heat island effect should focus on supporting
this area of the City.
Shifts in temperature and extreme heat will result in changes in energy demand for cooling in the City, with
increased demand in areas experiencing more severe urban heat island hotspots. As the City implements it’s
recently adopted Climate Action Plan and as well as the Resilient SLO strategies, solutions that both reduce GHG
emissions and help the City adapt to impacts of climate change should be prioritized.
The City’s historically moderate climate has, in general, not required the City’s existing building stock to be
designed or equipped with air conditioning. However, as average temperatures and extreme heat events increase
in the future, residents are ill-equipped to prepare for these events. Additionally, increases in temperature and
extreme heat will result in increased energy demand for cooling, which underscores the need to support
distributed energy resources, customer sited energy storage, demand response, and grid/building connected
appliances and vehicles.
Extreme heat days and heat waves will have a disproportionate impact on electricity demand, with higher
electricity demand projected for these events in the future. These projections place an increased urgency on
electricity utilities to plan for higher electricity demand during these events in future.
Community Resilience Findings
The Margarita Avenue Neighborhood (Census Tract 111.03) West of South Higuera neighborhood (Census Tract
115.01) is an area of the city with a particularly vulnerable population in regard to extreme heat, with a high
percentage of elderly, disabled, or low-income residents. The West of South Higuera neighborhood (Census
Tract 115.01) also includes a high percentage of elderly and disabled residents, making this area particularly
vulnerable to extreme heat impact.
Low-income residents are particularly vulnerable to extreme heat impacts due to a number of factors including a
higher reliance on public transit (leaving these residents more exposed to extreme heat during transit use), a
higher percentage of income being devot ed toward utility bills, and a trend of lower income neighborhoods
having less tree cover. Unhoused individuals are also at increased risk from extreme heat events with, generally,
less access to places to cool off and healthcare resources during these eve nts. DRAFTPage 364 of 669
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The City and the County, in general, have historically served as a destination for summer tourists to escape more
extreme summer heat in the San Joaquin Valley and southern California. As extreme heat events continue to
increase disproportionately in those areas of the state compared to less severe increases locally, the City may
experience increases in this phenomenon placing increased demand on services, impacts on City infrastructure
and resources, as well increased pressure on the housing shortage issue in the City from new permanent
residents.
LONG-TERM DROUGHT KEY FINDINGS
Natural System Findings
The City’s designated open space areas include a mixture of vegetation types including oak woodland, grassland,
coastal sage scrub, and chaparral that are anticipated to be impacted by changes in annual average
temperatures, extreme heat, and long -term droughts (OPR et al. 2018b).
As dry years and long-term droughts become more common in the future, population growth rates of annual
plant species will become marginal, and populations are likely to become locally extinct .
Built Environment Findings
Dramatic shifts from a multi -year dry periods to wet periods, similar to the 2011 -2015 drought followed by an
above average wet year in the 2016 -2017, are known as whiplash events (Swain et al. 2018), and are expected
to become more severe in the future. These whiplash events may affect water supply management practices
over the long -term, particularly as the swings from multi -year dry to wet periods become more prolonged and
more severe, with an emphasis on increasing rainfall storage when it does occur during t he wet periods
(Persad et al. 2020).
Buildup of sedimentation that reduces a reservoir’s volume available already occurs in the City’s water storage
system, with the City implementing programs and policies to address this storage loss over the long term. However,
landscape disturbances including wildfire, post-wildfire runoff, or landslides after wet winters, are projected to
increase sediment yield from watersheds along the Central Coast (OPR et al. 2018b) and with the potential to further
reduce the amount of water-storage capacity in dammed Central Coast reservoirs (Smith et al. 2018).
The City’s 2020 UWMP modeled potential impacts on the City’s water supplying, finding that changes in
precipitation could result in a decrease of as much as 850 AFY to an increase of as much as 160 AFY, accounting
for an approximately 8 percent decrease to 2 percent increase in the City’s overall water supply (City of San Luis
Obispo 2021b).
With more rapid shifts from dry to wet periods known as “whiplash events ,” precipitation will occur over shorter
more intense periods. This shift has the potential to reduce groundwater recharge which ideally occurs during
prolonged wet periods to allow for soil infiltration, deeper percolation, and more effective groundwater recharge.
However, increases in the intensity of rainfall events, when they do occur in the wet periods, provides an
opportunity to offset potential losses in storage during periods of drought.
The 2020 UWMP includes a section specially on Water Resiliency Planning which highlights a set of strategies the
City has taken to ensure long-term water resiliency and mitigate the impacts from a long -term drought scenario.
These strategies include a multi -source water supply; conservative water demand projections; water use
efficiency; water recycling; and future groundwater recharge.
Community Resilience Findings
Increases in temperature and extreme heat events are associated with increases in vector -borne and infectious
disease transmission, with future long-term drought scenarios potentially increasing the prevalence of certain
vector-borne diseases present on in the central coast region including Lyme disease and valley fever. DRAFTPage 365 of 669
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3-4 Climate Change Hazards and Vulnerability Report
WILDFIRE KEY FINDINGS
Natural System Findings
The increasing frequency of fire on chaparral landscapes have caused coastal sage shrubs and chaparral to shift
to grasses, including exotic grasses. Some research has suggested that annual and some perennial grasses have
the strongest effects on fire regimes and act as ecosystem transformers.
Wildfire impacts in riparian zones can reduce canopy cover, resulting in increased water temperatures in creeks
and other shaded waterways as well as produce increased sediment flux in stream beds and adjacent areas,
affecting the food web of burned stream a reas and increasing the density of algae in waterways.
Post-wildfire runoff and debris flows can be affected by several factors but are generally triggered by one of two
processes: surface erosion caused by rainfall runoff, and landslid es caused by rainfall seeping into the ground.
While it is uncertain the effect climate change will have on post -wildfire runoff and debris flows event, climate
change is projected to result in higher intensity rainfall events as well as “whiplash events” with oscillations
between extremely dry and extremely wet periods, potentially affecting post-wildfire hazards.
Built Environment Findings
The risk of wildfire is dependent on a variety of factors not excluding biophysical factors that are affected by
climate change including Resources (e.g., land use patterns, vegetation growth), Ignitions (e.g., lightning,
accidental ignitions, arson), and Conditions (e.g., precipitation, wind, seasonal variation). A pproximately 95
percent of wildfires in the state are caused by hum an ignition. However, climate change is projected to increase
the frequency and severity of wildfires , when they do occur (Mann et al. 2016).
The combination of dry climate conditions and the seasonal high autumn winds in California can increase the risk
of trees or branches falling on transmission lines and causing power outages or wildfires. While these events have
occurred historically, the effect of climate change on biophysical features that increase the risk of wildfires (e.g.,
precipitation, wind, seasonal variation) will increase the frequency and severity of wildfires from transmission line
ignitions.
There was limited development within the WUI in the city for the period of 2001 – 2016, with a few prominent
exceptions including the Madonna Area and the Margarita Area to the east of South Higuera Street. However,
buildings outside of the WUI are also at risk from ignition due to the spread of firebrands (or embers) that can
initiate new spot fires.
Wildfire events in the VHFHSZ near the Irish Hills Natural Reserve could potentially have immediate impacts to
some residential areas on Royal Way, Sterling Lane and Isabella Way. Additionally, areas in the northeast of the
City south of US 101 along San Luis Road are at risk from wildfire impacts a nd could potentially compromise
evacuation management when wildfires do occur in this area.
Community Resilience Findings
The City serves as regional employment center, regional destination for tourism, and home to a university (Cal
Poly) with approximately 20,000 students. These factors create an environment in which the City experiences a
large influx of daily visitors to the City. If and when a wildfire event were to occur in or near the City during
daytime hours, evacuation management would be particularly difficult and pose additional challenges due to this
large influx of daily visitors. Additionally, because US 101 serves the main commuter corridor for locations north
and south, wildfire events that occur along this route causing route closures (e .g., Cuesta Grade) can have
disproportionate impact on employers and employees in the City.
While the majority of the City is not at high risk from direct wildfire impacts, regional PSPSs events that affect the City
will result in a set of potential secondary impacts. Specifically, PSPS events occurring during heat wave events could
have considerable public health impacts, leaving residents and businesses without power and air conditioning and
create health impacts to those who are reliant of electricity for supplemental oxygen and refrigerated medications. DRAFTPage 366 of 669
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The confluence of PSPS, bad air quality, wildfire threat, and high heat days underscores the importance of homes
and businesses as places of potential refuge.
The Sinsheimer Neighborhood (Census Tract 110.01) and the Laguna Lake and Los Osos Valley Road (Census
Tract 113) are particularly vulnerable to wildfire impacts with this areas of the City near moderate to very high
FHSZs and include the higher percentages of elderly (20 percent) and youth (7 perc ent) populations as well as
the Laguna Lake and Los Osos Valley Road area with a high percentage of households experiencing linguistic
isolation (8 percent) which may present issues during emergency evacuation events.
Exposure to wildfire smoke, particula rly exposure to vulnerable populations, can result in worsening of respiratory
symptoms, increased rates of cardiorespiratory emergency visits, hospitalizations, and even death (Rappold et al.
2017). Wildfires can damage not only buildings and infrastructu re, but also the natural environment, including
portions of the City and the areas in the County that serve as regional recreation and tourism opportunities, resulting
in economic impacts on the tourism and related industries when wildfire smoke impacts oc cur.
Precipitation Key Considerations
Natural Systems Findings
Although annual precipitation is anticipated to increase in the City and the larger central coast region, California’s
climate oscillates between extremely dry and extremely wet periods with annual precipitation varying widely from
year to year. These oscillations between extremely dry and extremely wet periods are anticipated to become more
severe with rapid shifts from dry to wet periods known as “whiplash events” (Swain et al. 2016). These types of
events are estimated to increase by approximately 100 percent in southern California, with increases in frequency
occurring largely after 2050 (Swain et al. 2016).
Based on California’s location next to the Pacific Ocean, the state is exposed to the atmospheric river (AR)
phenomenon, a narrow corridor of concentrated moisture in the atmosphere. The presence of the AR contributes
to the frequency of “wet years” in the state, when there is an above-average number of AR storms and above-
average annual precipitation. While research indicates that the frequency of large storms events does increase in
these wet years, the most severe flooding from ARs may not be in wet years (Swain et al. 2018). The largest flooding
impacts are caused by persistent storm sequences on sub-seasonal timescales (i.e., short time periods, typically 2
weeks to 3 months), which bring a significant fraction of annual average precipitation over a brief period. Based on
current climate modeling, the frequency of these large storm sequences over short timeframes is projected to
increase noticeably under a future high emissions scenario. It is estimated that a storm similar in magnitude to the
Great Flood events is more likely than not to occur at least once between 2018 and 2060 (Swain et al. 2018).
For very large precipitation events, the capacity of the watershed to absorb incoming rainfall can be quickly
exceeded, causing large increases in stream flow within the system. By as early as 2070 under a high future
emissions scenario, peak flow rates in the San Luis Obispo Creek watershed are projected to increase, on average,
from 17 percent to 38 percent depending on the size of the storm event. By this period, for the storm event with a
50 percent chance of occurring in any given year (2-year storm event), the median peak stream flow is projected to
increase by 28 percent with a small likelihood (90th percentile) of stream flow increasing by 51 percent.
Built Environment Findings
By as early as 2070 under a high future emissions scenario, for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek confluence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infras tructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confluence DRAFTPage 367 of 669
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3-6 Climate Change Hazards and Vulnerability Report
From the results of the climate-informed flood modeling, areas with the greatest increases in connected
floodplain inundation for the 10-year through 100-year events included SLO Creek upstream of the Stenner
confluence (including parts of downtown SLO), the SLO Creek – Prefumo Creek confluence area, East Fork and its
tributaries upstream of Buckley Road, and Stenner, Brizziolari, and Old Garden Creeks. In the modeling, these
areas tended to have greater expanses of floodplain areas, such as the SLO Creek – Prefumo Creek confluence
area, or limiting infrastructure, as is the case with the undercity culvert through downtown.
By as early as 2070 under a high future emissions scenario , for the 100-year event, dramatic increases are
observed on Stenner and Old Garden Creeks upstream of the San Luis Obispo Creek confluence and within the
downtown area. In both cases, flooding is exacerbated by the capacity of the existing infrastructure to manage
historic flooding events. Similar, during the 100-year event, increases in flow within San Luis Obispo Creek
increasingly cause flood waters to break out of the channel upstream of the culvert and flow along the Higuera
and Marsh Street corridor towards the Stenner Creek confl uence.
Near the San Luis Obispo – Prefumo Creek confluence area near Higuera Street and Madonna Road, large
expanses of relatively flat, low-lying land persist between and along the two creeks. During larger storm events
(50-year and 100-year storms), flood waters can spill into these areas by crossing Highway 101 near Madonna
Road from San Luis Obispo Creek or by escaping the creek channels in the confluence area and causing
backwater conditions for upstream reaches.
The greatest area of impact to local roads during large storm events (100-year storm) would be areas just south
of San Luis Obispo Creek through the downtown area with the farthest extent along Santa Barbara Street as far
South as Leff Street. The Chorro Street undercrossing at US 101 would be impacted by the 10-year, 100-year, and
500-year floods.
Extensive flooding from larger storm events also has the potential to limit transit service, thus eliminating
transport options for populations in the City dependent on transit, with between 16 to 26 percent of SLO Transit
stops being affected depending on the storm size.
Community Resilience Findings
For all flooding events (i.e., 100-year and 500-year flood events), access to the Southern Gateway of US 101 is
compromised due to potential flooding of US 101 and Los Osos Valley Road. However, all centroids under these
scenarios are able to access at least one alternative City gateway, which means no portions of the C ity would be
closed off due to roadway network flooding.
The 500-year flood scenario, illustrated in Figure 42, shows an inability of four census block groups to access
either the City gateways or evacuation centers as they experience extensive flooding, i solating their ability to
connect to a route.
There is significant overlap between areas in the City where disadvantaged communities have been identified
and the 100- and 500-year floodplain, resulting in potentially disproportionate impacts on these popul ations in
the City during large storm events.
The area West of South Higuera Street (Census Tract 115.01) is located almost entirely within the 100 - and 500-
year flood plain which is anticipated to expand in the future due to climate change. This area is particularly
vulnerable with high percentage of elderly residents (17 percent) as well as a high percent of disabled residents
(15 precent), presenting potential challenges during emergency evacuation events.
Increased heavy precipitation and flooding will disproportionately impact homeless populations because they
occupy marginal areas, they are less able to transport themselves out of flood areas during these events.
DRAFTPage 368 of 669
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4-6 Climate Change Hazards and Vulnerability Report
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Appendix A
Flood Risk Modeling and
Wildland Urban Interface Maps
DRAFTPage 375 of 669
Islay Hill
Terrace
Hill
Reservior Canyon
Natural Reserve
Johnson Ranch
Bishop Peak
Natural Reserve
Irish Hills
Natural Reserve
South Hills
Laguna Lake
Natural Reserve
Miossi
Open Space
Rigetti
Hill
ab101
ab101
ÃÅ1
ÃÅ227
0 5,000 10,000FEET
Model Reaches
Model Cross Sections
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763Stenner C re e k
B r iz z io la r iCreekSt
enner - Old Gardens CreeksP refumo Cre
e
kSan Luis Obispo CreekE a s t F o r k
San Luis Obispo CreekSan Luis Ob is p o C r e e k
Page 376 of 669
SLO-4
STEN
SLO-5
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
S an Luis O b isp o CreekStenner CreekOld Garden CreekPage 377 of 669
SLO-4
STEN
SLO-5
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
S an Luis O b isp o CreekStenner CreekOld Garden CreekPage 378 of 669
SLO-4
STEN
SLO-5
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
S an Luis O b isp o CreekStenner CreekOld Garden CreekPage 379 of 669
SLO-4
STEN
SLO-5
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
S an Luis O b isp o CreekStenner CreekOld Garden CreekPage 380 of 669
SLO-4
LGNA
SLO-2
SLO-3
Laguna Lake
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5San Luis Obispo CreekPrefumo CreekPage 381 of 669
SLO-4
LGNA
SLO-2
SLO-3
Laguna Lake
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5San Luis Obispo CreekPrefumo CreekPage 382 of 669
SLO-4
LGNA
SLO-2
SLO-3
Laguna Lake
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5San Luis Obispo CreekPrefumo CreekPage 383 of 669
SLO-4
LGNA
SLO-2
SLO-3
Laguna Lake
0 500 1,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5San Luis Obispo CreekPrefumo CreekPage 384 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 385 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q10 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 386 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q50 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 387 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q50 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 388 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 389 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
EFK-1
EFK-2
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q100 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 390 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q500 (Historic)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 391 of 669
ab101
ab101
ÃÅ1
ÃÅ227
SLO-4
LGNA
SLO-2
SLO-1
SLO-3
STEN
SLO-5
Laguna Lake
0 2,500 5,000FEET
San Luis Obispo City Limits
Digital Elevation Model
Elevation NAVD88 (ft)
0.0
2763
Analysis Regions
Excluded Areas
Q500 (Future)
Depth (ft)
0 - 1
1 - 2
2 - 3
3 - 4
4 - 5
> 5
Page 392 of 669
Appendix A Compliance with State Laws and Regulations
Senate Bill 379 (Climate Change Adaptation and Resilience)
SB 379 (2015) mandates that climate adaptation and resilience are considered in safety elements. The legislation
specifically requires that safety elements include a vulnerability assessment that identifies climate change impacts to the
jurisdiction, and a suite of goals, policies, objectives, and feasible implementation measures to protect the community from
risks posed by climate change.
Senate Bill 99 (Emergency Evacuation Routes)
SB 99 (2019) requires safety elements to include information that identifies residential developments in hazard areas without
at least two emergency evacuation routes.
Assembly Bill 747 (Emergency Evacuation Routes)
Assembly Bill (AB) 747 (2019) requires that safety elements are reviewed and updated as needed to identify evacuation
routes and their capacity, safety, and viability under a range of emergency scenarios. An adopted local hazard mitigation
plan, emergency operations plan, or other document that fulfills these requirements, may be summarized, and incorporated
by reference into the safety element to comply.
Senate Bill 1000 (Environmental Justice)
SB 1000 (2016) requires communities with disadvantaged communities to address environmental justice in the general
plan. Disadvantaged communities are defined by State law and generally refer to areas disproportionately affected by
environmental pollution or other hazards that can lead to negative health effe cts, exposure, or environmental degradation.
Under the law, cities and counties with communities that meet the definition of disadvantaged under the law must address
unique or compound health risks in these communities, promote civil engagement in the publ ic decision-making process,
and prioritize programs and improvements that address the needs of these communities. While the city does not have any
State designated disadvantaged communities, some of its populations may be less resilient to hazards due to
socioeconomic factors. Therefore, the City has voluntarily chosen to address environmental justice issues through this
element.
Page 393 of 669
Alquist-Priolo Earthquake Faulting Zone Act
The Alquist-Priolo Earthquake Faulting Zone Act was passed in 1971 with the intent of reducing risk of loss from surface
fault rupture. The act provides guidance for cities on prohibiting development across the trace of active faults.
National Flood Insurance Program
The Federal Emergency Management Agency (FEMA) insures properties against flooding losses through the National Flood
Insurance Program. The City has been a participant in the National Flood Insurance Program since April 16, 1979 and will
continue to participate and remain in compliance with the National Flood Insurance Program. The City joined the Community
Rating System on October 1, 1991, and currently has a Class 6 rating.
Page 394 of 669
CODE+A1A
1:G23 TIMELINE / ENFORCEMENT TOPIC STATE GUIDANCE LEGISLATION
§ 65302 g.1.
Before preparing or revising its safety element, each city and
county shall consult the California Geological Survey of the
Department of Conservation, the Central Valley Flood Protection
Board, if the city or county is located within the boundaries of the
Sacramento and San Joaquin Drainage District, and the Office of
Emergency Services for the purpose of including information known
by and available to the department, the agency, and the board
required by this subdivision.
To the extent that a county’s safety element is sufficiently detailed
and contains appropriate policies and programs for adoption by a
city, a city may adopt that portion of the county’s safety element
that pertains to the city’s planning area in satisfaction of the
requirement imposed by this subdivision.
§ 65302 g.1.Hazards
§ 65302 g.1.Hazards
§ 65302 g.2.A.
Cities and counties that have flood plain management ordinances
that have been approved by FEMA that substantially comply with
this section, or have substantially equivalent provisions to this
subdivision in their general plans, may use that information in the
safety element to comply with this subdivision, and shall
summarize and incorporate by reference into the safety element
the other general plan provisions or the flood plain ordinance,
specifically showing how each requirement of this subdivision has
been met.
Flood
§ 65302 g.2.A.i.
Flood hazard zones. As used in this subdivision, “flood hazard zone” means an area subject to flooding
that is delineated as either a special hazard area or an area of moderate or minimal hazard on an
official flood insurance rate map issued by FEMA. The identification of a flood hazard zone does not
imply that areas outside the flood hazard zones or uses permitted within flood hazard zones will be free
from flooding or flood damage.
Flood
§ 65302 g.2.A.ii.National Flood Insurance Program maps published by FEMA.Flood
§ 65302 g.2.A.iii.Information about flood hazards that is available from the United States Army Corps of Engineers.Flood
§ 65302 g.2.A.iv.Designated floodway maps that are available from the Central Valley Flood Protection Board.Flood
§ 65302 g.2.A.ix.Historical data on flooding, including locally prepared maps of areas that are subject to flooding, areas
that are vulnerable to flooding after wildfires, and sites that have been repeatedly damaged by flooding.Flood
§ 65302 g.2.A.v.Dam failure inundation maps prepared pursuant to Section 6161 of the Water Code that are available
from the Department of Water Resources.Flood
§ 65302 g.2.A.vi.Awareness Floodplain Mapping Program maps and 200-year flood plain maps that are or may be
available from, or accepted by, the Department of Water Resources.Flood
§ 65302 g.2.A.vii.Maps of levee protection zones.Flood
§ 65302 g.2.A.viii.Areas subject to inundation in the event of the failure of project or nonproject levees or floodwalls.Flood
§ 65302 g.2.A.x.Existing and planned development in flood hazard zones, including structures, roads, utilities, and
essential public facilities.Flood
§ 65302 g.2.A.xi.Local, state, and federal agencies with responsibility for flood protection, including special districts and
local offices of emergency services.Flood
Include mapping of known seismic and other geologic hazards.
Address evacuation routes, military installations, peak load water supply requirements, and minimum road
widths and clearances around structures, as those items relate to identified fire and geologic hazards.
Identify information regarding flood hazards, including but not limited to:
LOCAL PLANNING REQUIREMENTS
SAFETY ELEMENT
A safety element for the protection of the community from any unreasonable risks associated with the
effects of seismically induced surface rupture, ground shaking, ground failure, tsunami, seiche, and dam
failure; slope instability leading to mudslides and landslides; subsidence; liquefaction; and other seismic
hazards, and other geologic hazards known to the legislative body; flooding; and wildland and urban fires.
Page 395 of 669
§ 65302 g.2.B.Flood
§ 65302 g.2.B.i.Avoiding or minimizing the risks of flooding to new development.Flood
§ 65302 g.2.B.ii.
Evaluating whether new development should be located in flood hazard zones, and identifying
construction methods or other methods to minimize damage if new development is located in flood
hazard zones.
Flood
§ 65302 g.2.B.iii.Maintaining the structural and operational integrity of essential public facilities during flooding.Flood
§ 65302 g.2.B.iv.
Locating, when feasible, new essential public facilities outside of flood hazard zones, including
hospitals and health care facilities, emergency shelters, fire stations, emergency command centers,
and emergency communications facilities or identifying construction methods or other methods to
minimize damage if these facilities are located in flood hazard zones.
Flood
§ 65302 g.2.B.v.Establishing cooperative working relationships among public agencies with responsibility for flood
protection.Flood
§ 65302 g.2.C.Flood
§ 65302 g.3.
Fire safety plan or document separate from the general plan, an
attachment of, or reference to, a city or county’s adopted fire safety
plan or document that fulfills commensurate goals and objectives
and contains information required pursuant to this paragraph.
Fire
OPR Fire Hazard Technical
Advisory (2020 Public Review
Draft)
§ 65302 g.3.A.Fire
§ 65302 g.3.A.i.Fire hazard severity zone maps available from the Department of Forestry and Fire Protection.Fire
§ 65302 g.3.A.ii.Any historical data on wildfires available from local agencies or a reference to where the data can be
found.Fire
§ 65302 g.3.A.iii.Information about wildfire hazard areas that may be available from the United States Geological Survey.Fire
§ 65302 g.3.A.iv.
General location and distribution of existing and planned uses of land in very high fire hazard severity
zones and in state responsibility areas, including structures, roads, utilities, and essential public
facilities. The location and distribution of planned uses of land shall not require defensible space
compliance measures required by state law or local ordinance to occur on publicly owned lands or
open space designations of homeowner associations.
Fire
§ 65302 g.3.A.v.Local, state, and federal agencies with responsibility for fire protection, including special districts and
local offices of emergency services.Fire
§ 65302 g.3.B.Fire
§ 65302 g.3.C.Fire
§ 65302 g.3.C.i.Avoiding or minimizing the wildfire hazards associated with new uses of land.Fire
§ 65302 g.3.C.ii.
Locating, when feasible, new essential public facilities outside of high fire risk areas, including, but not
limited to, hospitals and health care facilities, emergency shelters, emergency command centers, and
emergency communications facilities, or identifying construction methods or other methods to
minimize damage if these facilities are located in a state responsibility area or very high fire hazard
severity zone.
Fire
§ 65302 g.3.C.iii.
Designing adequate infrastructure if a new development is located in a state responsibility area or in a
very high fire hazard severity zone, including safe access for emergency response vehicles, visible
street signs, and water supplies for structural fire suppression.
Fire
§ 65302 g.3.C.iv.Working cooperatively with public agencies with responsibility for fire protection.Fire
Include information regarding fire hazards, including, but not limited to:
Include a set of comprehensive goals, policies, and objectives based on fire hazard information for the
protection of the community from the unreasonable risk of wildfire.
A set of feasible implementation strategies to carry out the goals, policies, and objectives for the
protection of the community from the unreasonable risk of wildfire.
Establish a set of comprehensive goals, policies, and objectives based on flood hazard information for the
protection of the community from the unreasonable risks of flooding, including but not limited to:
Establish a set of feasible implementation strategies to carry out the goals, policies, and objectives
established for the protection of the community from the unreasonable risks of flooding.
Address the risk of fire for land classified as state responsibility areas, as defined in Section 4102
of the Public Resources Code, and land classified as very high fire hazard severity zones, as
defined in Section 51177. Consider the advice included in the Office of Planning and Research’s
most recent publication of “Fire Hazard Planning, General Plan Technical Advice Series.”
Page 396 of 669
§ 65302 g.4.
If a city or county has adopted the local hazard mitigation plan, or
other climate adaptation plan or document that fulfills
commensurate goals and objectives and contains the information
required pursuant to this paragraph, separate from the general plan,
an attachment of, or reference to, the local hazard mitigation plan
or other climate adaptation plan or document.
Cities or counties that have an adopted hazard mitigation plan, or
other climate adaptation plan or document that substantially
complies with this section, or have substantially equivalent
provisions to this subdivision in their general plans, may use that
information in the safety element to comply with this subdivision,
and shall summarize and incorporate by reference into the safety
element the other general plan provisions, climate adaptation plan
or document, specifically showing how each requirement of this
subdivision has been met.
Adaptation OPR General Plan Guidelines
SB-379 (2015) Vulnerability
Assessment and Hazard
Mitigation Plan in Safety
Element
§ 65302 g.4.A.Adaptation Cal-Adapt, 2020 California
Adaptation Planning Guide
§ 65302 g.4.B.Adaptation
§ 65302 g.4.C.Adaptation
§ 65302 g.4.C.i.Feasible methods to avoid or minimize climate change impacts associated with new uses of land.Adaptation
§ 65302 g.4.C.ii.
The location, when feasible, of new essential public facilities outside of at-risk areas, including, but not
limited to, hospitals and health care facilities, emergency shelters, emergency command centers, and
emergency communications facilities, or identifying construction methods or other methods to
minimize damage if these facilities are located in at-risk areas.
Adaptation
§ 65302 g.4.C.iii.The designation of adequate and feasible infrastructure located in an at-risk area.Adaptation
§ 65302 g.4.C.iv.Guidelines for working cooperatively with relevant local, regional, state, and federal agencies.Adaptation
§ 65302 g.4.C.v.
The identification of natural infrastructure that may be used in adaptation projects, where feasible.
Where feasible, the plan shall use existing natural features and ecosystem processes, or the
restoration of natural features and ecosystem processes, when developing alternatives for
consideration. For purposes of this clause, “natural infrastructure” means using natural ecological
systems or processes to reduce vulnerability to climate change related hazards, or other related
climate change effects, while increasing the long-term adaptive capacity of coastal and inland areas by
perpetuating or restoring ecosystem services. This includes, but is not limited to, the conservation,
preservation, or sustainable management of any form of aquatic or terrestrial vegetated open space,
such as beaches, dunes, tidal marshes, reefs, seagrass, parks, rain gardens, and urban tree
canopies. It also includes systems and practices that use or mimic natural processes, such as
permeable pavements, bioswales, and other engineered systems, such as levees that are combined
with restored natural systems, to provide clean water, conserve ecosystem values and functions, and
provide a wide array of benefits to people and wildlife.
Adaptation
§ 65302 g.5.Upon the next revision of the housing element on or after January 1,
2020.Evacuation
SB-99 (2019) General
Plans/Safety
Element/Emergency
Evacuation
§ 65302 g.6.Upon each revision of the housing element or local hazard
mitigation plan, but not less than once every eight years.Adaptation SB-1035 (2018) General
Plans
§ 65302 h.1.
A city, county, or city and county subject to this subdivision shall
adopt or review the environmental justice element, or the
environmental justice goals, policies, and objectives in other
elements, upon the adoption or next revision of two or more
elements concurrently on or after January 1, 2018.
General Plan Guidelines
Chapter 4: Environmental
Justice Element
SB-1000 (2016)
Environmental Justice
Requirements in General Plan
§ 65302 h.1.A.Environmental
Justice
§ 65302 h.1.B.Environmental
Justice
§ 65302 h.1.C.Environmental
Justice
Identify objectives and policies that prioritize improvements and programs that address the needs of
disadvantaged communities.
Include a set of feasible implementation measures designed to carry out the goals, policies, and
objectives identified for the protection of the community.
Identify residential developments in any hazard area identified in the safety element that do not
have at least two emergency evacuation routes
Review and, if necessary, revise the safety element to identify new information relating to flood
and fire hazards and climate adaptation and resiliency strategies applicable to the city or ENVIRONMENTAL JUSTICE ELEMENT
An environmental justice element, or related goals, policies, and objectives integrated in other elements,
that identifies disadvantaged communities within the area covered by the general plan of the city, county,
or city and county, if the city, county, or city and county has a disadvantaged community.
"Disadvantaged community" - low-income area that is disproportionately affected by environmental Identify objectives and policies to reduce the unique or compounded health risks in disadvantaged
communities by means that include, but are not limited to, the reduction of pollution exposure, including
Identify objectives and policies to promote civic engagement in the public decisionmaking process.
Address climate adaptation and resiliency strategies applicable to the city or county. Consider
advice provided in the Office of Planning and Research’s General Plan Guidelines.
Include a vulnerability assessment that identifies the risks that climate change poses to the local
jurisdiction and the geographic areas at risk from climate change impacts.
Include a set of adaptation and resilience goals, policies, and objectives based on the information
specified in the vulnerability assessment for the protection of the community.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.1
G.1 Community Profile
G.1.1 Mitigation Planning History and 2019 Process
Annex G, City of San Luis Obispo (City), was created during the development of the 2019 Multi-Jurisdictional San
Luis Obispo Hazard Mitigation Plan update (HMP). This Jurisdictional Annex builds upon and supersedes the
2014 City of San Luis Obispo Local Hazard Mitigation Plan (LHMP). The 2014 Plan was not integrated into the
City’s Land Use Element; that integration will be done after the approval of this updated Plan. The General Plan
Safety Element references the 2014 Local Hazard Mitigation Plan in Chapter 5:
Additional information on hazards in the San Luis Obispo area can be found in the Technical Background
Report for the San Luis Obispo County and Cities Safety Element (June 1999). Additionally, the City of San
Luis Obispo Local Hazard Mitigation Plan presents a comprehensive risk assessment of natural hazards that
have the potential to affect the City of San Luis Obispo. The Local Hazard Mitigation Plan was developed by
the City in accordance with the Federal Disaster Mitigation Act of 2000, adopted by the City Council and
approved by the Federal Emergency Management Agency. The Local Hazard Mitigation Plan suggests
possible mitigation actions for reducing the effects of potential hazards. It is incorporated by reference into
the Safety Element and should be consulted when addressing known hazards to ensure the general health
and safety of people within the City of San Luis Obispo. The goals and policies within this Safety Element
support and are consistent with the recommended mitigation strategy within the Local Hazard Mitigation
Plan.
The City had representation on the County multi-jurisdictional Hazard Mitigation Planning Committee and
utilized a Local Planning Team (LPT) subcommittee to develop input into the annex.
Table G.1 City of San Luis Obispo Local Planning Team
Department or Stakeholder Title
Fire Department Fire Chief
Fire Department Fire Marshall
Fire Department Administrative Analyst
Administration Natural Resources Manager
Administration Sustainability Manager
More details on the planning process and participating jurisdictions, service districts and stakeholders can be
found in Section 3 of the Base Plan, along with the public’s role during the 2019 update.
G.1.2 Geography and Climate
The City is located in California’s Central Coast region approximately 200 miles north of Los Angeles and 230
miles south of San Francisco. The City is situated to the west of the Santa Lucia Mountains and is located eight
miles east of the Pacific Ocean. The San Luis Obispo Creek originates from the mountains and flows westward in
confluence with the Pacific Ocean at Avila Beach. The mountain ranges form a natural barrier to development in
San Luis Obispo. The City is an estimated 10.7 square miles and is surround ed by protected open space and
productive agricultural lands. San Luis Obispo is regionally accessible via US Highway 1, US Highway 101, and
State Route 227 (Broad Street). The City terrain stands at an average elevation of 300 feet above sea level, with
prominent peaks such as Cerro San Luis and Bishop Peak at 1,292 and 1,559 feet, respectively, above sea level.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.2
The City’s Sphere of Influence includes approximately 5,930+/- acres outside of the City limits and includes nine
unincorporated areas: Cal Poly, Florita-Alrita, Orcutt, Broad Street, Airport, Chevron, Los Osos Valley Road/US
Highway 101, San Luis Ranch, and Cerro San Luis area. All lands outside of the City’s Sphere of Influence are
regulated by the San Luis Obispo County General Plan and zoning designations. State law requires that cities
maintain plans for areas outside of their immediate jurisdiction if the areas have a direct relationship to planning
needs.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.3
Figure G.1 The City of San Luis Obispo
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.4
San Luis Obispo is characterized by a Mediterranean climate with an average temperature of 70.2 degrees
Fahrenheit. While generally considered a mild climate, weather patterns and events have historically observed
both unseasonably warm periods and cold spells. The City receives an average precipitation of 19 inches per
year, with increased amounts of rainfall in the winter and spring months between November and April (US
Climate Data 2019). Due to its close proximity to the Pacific Ocean, San Luis Obispo is also subject to coastal
weather influences such as dense fog that typically rolls into the City through the Chorro Valley, steady on-shore
wind patterns, and coastal storms. For general details on climate characteristics of the region refer to the
Adverse Weather Section of the Risk Assessment in the HMP (Section 5.3.1).
G.1.3 History
The native Chumash Tribe was the first known settled human population in the City of San Luis Obispo area. The
Chumash established a network of villages along the San Luis Obispo Creek. Spanish Colonization of the area
began in 1769 with the founding of Mission San Luis Obispo de Tolosa in 1772 by Father Junipero Serra ,
resulting in devastating impacts to the Chumash culture. Diseases and significant alterations of culture due to
the establishment of the mission caused a significant decrease in the Native American population. Spanish and
Mexican ranchos were established in the area in the late 1700s. The development of the area of San Luis Obispo
has historically been connected to the San Luis Obispo Creek, where the first settlements could be found, and to
the emphasis on agricultural production by the Mission and later the adjacent ranchos.
The California Land Act of 1851 caused a shift to residential development in San Luis Obispo. By 1870, the
community had grown to a population of 1,579 and it became a charter city in 1876. Historic influences on the
growth and development of San Luis Obispo include the City’s beginnings as a center for agricultural
productivity, the extension of the Southern Pacific Railroad in 1894, and the establishment of California
Polytechnic State University (Cal Poly) in 1901.
Agriculture, transportation, government, and education related activities continue to play a significant role in the
demographic, economic, land use, and development characteristics of the City. These characteristics and
proactive protection of the City’s natural and scenic resources contribute to the small-town charm and high
quality of life of the City’s residents.
G.1.4 Economy
As the civic, economic, and cultural hub of the Central Coast, the City serves as the seat of the County of San Luis
Obispo. With major regional employers such as Cal Poly, state agencies, PG&E, Tenet Health Care, and the
County of San Luis Obispo, the City has an estimated daytime population of more than 70,000 people. The San
Luis Obispo Chamber of Commerce and the Downtown Association are active collaborators and leaders in
supporting the retention and expansion of local businesses in the City. The City’s leading industries include
hospitality, food services, retail, professional services, health care, information and technology, public
administration, and educational sectors.
To support the high quality of life and economic vitality of the community, San Luis Obispo is considered a full-
service city, providing police, fire, water, sewer, streets, transit, parking, planning, building, engineering, and
parks and recreation services to the community.
Select estimates of economic characteristics for the City of San Luis Obispo are shown in Table G.2.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.5
Table G.2 City of San Luis Obispo Economic Characteristics, 2017
Characteristic City of San Luis Obispo
Families below Poverty Level 6.9%
All People below Poverty Level 32.4%
Median Family Income $87,635
Median Household Income $49,640
Per Capita Income $29,748
Population in Labor Force 25,363
Population Employed* 41,668
Unemployment 1,128
Source: U.S. Census Bureau American Community Survey 2017, www.census.gov/
Excludes armed forces
Table G.3 and Table G.4 show the occupational and industry breakdown of the City of San Luis Obispo’s labor
force based on estimates from the 2017 American Community Survey.
Table G.3 City of San Luis Obispo’s Employment by Occupation, 2017
Occupation # Employed % Employed
Sales and Office Occupations 5,630 21.6%
Management, Business, Science, and Arts Occupations 10,777 44.5%
Natural Resources, Construction, and Maintenance Occupations 934 3.9%
Production, Transportation, and Material Moving Occupations 1,632 6.7%
Service Occupations 5,240 21.6%
Total 24,213
Source: U.S. Census Bureau American Community Survey 2017, www.census.gov/
Excludes armed forces
Table G.4 City of San Luis Obispo’s Employment by Industry, 2017
Industry # Employed % Employed
Retail Trade 3,044 12.6%
Professional, Scientific, and Mgmt., and Administrative and Waste Mgmt. Services 2,879 11.9%
Manufacturing 1,585 6.5%
Arts, Entertainment, and Recreation, and Accommodation, and Food Services 4,292 17.7%
Construction 886 3.7%
Finance and Insurance, and Real Estate and Rental and Leasing 846 3.5%
Public Administration 948 3.9%
Other Services, Except Public Administration 1,281 5.3%
Wholesale Trade 509 2.1%
Transportation and Warehousing, and Utilities 731 3.0%
Agriculture, Forestry, Fishing and Hunting, and Mining 269 1.1%
Information 457 1.9%
Educational Services, and Health Care, and Social Assistance 6,486 26.8%
Total 24,213
Source: U.S. Census Bureau American Community Survey 2017, www.census.gov/
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.6
G.1.5 Population
In May 2019, the State Department of Finance released preliminary population data for the state to reflect
wildfire-driven changes to local populations. The City of San Luis Obispo has a population of 46,802 persons as
of January 2019, which accounts for approximately 16.7% of the County’s population. The City experienced a
growth of 0.1% from 46,741 residents from January 2018 (Department of Finance 2019). The U.S. Census
Bureau’s American Community Survey 2017 5-Year Estimates provide select demographic and social
characteristics and changes from 2012 to 2017 for the City of San Luis Obispo (Table G.5).
Table G.5 City of San Luis Obispo’s Demographic and Social Characteristics, 2012 to 2017
Characteristic 2012 2017
Population 270,121 280,119
Median Age 39.3 39.0
Total Housing Units 117,318 120,182
Housing Occupancy Rate 86.7% 87.4%
of Housing Units with no Vehicles Available 4.5% 4.5%
Median Home Value $449,300 $499,800
Unemployment 8.7% 4.8%
Mean Travel Time to Work (minutes) 20.9 21.8
Median Household Income $59,628 $67,175
Per Capita Income $30,218 $33,972
of Individuals Below Poverty Level 13.7% 13.8%
of Households 101,708 105,044
Average Household Size 2.49 2.51
of Population Over 25 with High School Diploma 89.5% 90.5%
of Population Over 25 with Bachelor’s Degree or Higher 31.5% 34.0%
with Disability 11.1% 11.1%
Speak English less than "Very Well" 6.7% 6.8%
Source: U.S. Census Bureau American Community Survey 2017 5-Year Estimates, www.census.gov/
Between 1950 and 1990, the City grew from a population of 14,180 to just under 42,0 00. Since 1990, the City has
maintained an average growth rate of less than one percent per year. Owner -occupied housing units account for
39% of all households, while approximately 61% of households are renter -occupied. The City’s population is
growing steadily at a relatively slow rate at approximately 1% or less per year with an estimated of 5.3% growth
since the 2010 Census. The SLO 2035 Land Use and Circulation Elements update provides population estimates
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.7
Table G.6 City of San Luis Obispo Population Growth
Year Approximate Maximum
Number of Housing Units
Projected
Population
2013 20,697 45,541
2015 21,113 46,456
2020 22,190 48,826
2025 23,322 51,317
2030 24,512 53,934
2035 25,762 56,686
Source: SLO 2035 Land Use Element Update
G.1.6 Development Trends
The City has traditionally expanded through annexation of County lands and increased development of diverse
land uses; these include low to high density residential, general retail and commercial, services, and
manufacturing uses bordering the San Luis Obispo Regional Airport , and dispersed undeveloped open space.
With Mission Plaza and downtown at the heart of the City, development trends have included transition from the
historic neighborhoods immediately adjacent to Downtown, to post-World War II growth in areas along the
foothills of the Santa Lucia Mountains, surrounding Laguna Lake, and in the northern areas of town near the
growing Cal Poly. Recent development efforts have focused on incorporating additional housing opportunities
in the historic downtown core, through the renovation of historic structures and infill development on
underutilized and vacant land. The Land Use Element of the City’s General Plan provides designated land use
and establishes development standards for new and existing structures and uses. The Safety Element further
identifies hazards that may influence the locations and types of proposed land uses and provides policies that
reduce exposure to hazards. These policies have also encouraged changes to development in San Luis Obispo’s
hazard prone/vulnerable areas, decreasing the City’s vulnerability. Any future development within the City will be
informed by the most up to date hazard maps as well as state and local development ordinances (e.g.
floodplain) that restrict development in hazard prone areas to minimize risk.
In recent years, more residents and visitors are staying and living in the downtown core. This change in
demographic could impact response capabilities if a hazard impacts the downtown core. The City also has a
greenbelt protection program and have acquired thousands of acres of land around the City to minimalize
development in areas around the City. Thus, the redevelopment of already developed areas or infill
development is likely to be the trend in the future.
Specific to hazards, continuing moderate population growth is increasing exposure to earthquake hazards,
though new or re-developed areas built to modern codes will be more resistant to collapse and damage.
G.2 Hazard Identification and Summary
San Luis Obispo’s planning team identified the hazards that affect the region and summarized their frequency of
occurrence, spatial extent, potential magnitude, and significance specific to the City (see Table G.7). There are no
hazards that are unique to the City. The overall hazard significance takes into account the geographic area,
probability and magnitude as a way to identify priority hazards for mitigation purposes. This is discussed further
in the Vulnerability Section (4.3).
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.8
Table G.7 City of San Luis Obispo – Hazard Summaries
Hazard Geographic
Area
Probability of
Future
Occurrence
Magnitude/
Severity (Extent)
Overall
Significance
Adverse Weather: Thunderstorm/
Heavy Rain/Hail/Lightning/Dense
Fog/Freeze
Extensive Likely Limited Medium
Adverse Weather: High Wind/
Tornado
Extensive Occasional Limited Medium
Adverse Weather: Extreme Heat Extensive Occasional Negligible Low
Agricultural Pest Infestation and
Disease Limited Highly Likely Negligible Medium
Biological Agents Extensive Occasional Critical Medium
Drought and Water Shortage Extensive Likely Limited Medium
Earthquake Extensive Occasional Catastrophic High
Flood Limited Occasional Limited Medium
Landslides and Debris Flow Limited Occasional Limited Low
Subsidence Significant Occasional Negligible Low
Wildfire Significant Occasional Limited Medium
Human Caused: Hazardous Materials Significant Highly Likely Negligible Medium
Geographic Area
Limited: Less than 10% of planning area
Significant: 10-50% of planning area
Extensive: 50-100% of planning area
Probability of Future Occurrences
Highly Likely: Near 100% chance of occurrence in next
year or happens every year.
Likely: Between 10-100% chance of occurrence in next
year or has a recurrence interval of 10 years or less.
Occasional: Between 1 and 10% chance of occurrence
in the next year or has a recurrence interval of 11 to
100 years.
Unlikely: Less than 1% chance of occurrence in next
100 years or has a recurrence interval of greater than
every 100 years.
Magnitude/Severity (Extent)
Catastrophic—More than 50 percent of property severely
damaged; shutdown of facilities for more than 30 days; and/or
multiple deaths
Critical—25-50 percent of property severely damaged; shutdown
of facilities for at least two weeks; and/or injuries and/or illnesses
result in permanent disability
Limited—10-25 percent of property severely damaged; shutdown
of facilities for more than a week; and/or injuries/illnesses
treatable do not result in permanent disability
Negligible—Less than 10 percent of property severely damaged,
shutdown of facilities and services for less than 24 hours; and/or
injuries/illnesses treatable with first aid
Significance
Low: minimal potential impact
Medium: moderate potential impact
High: widespread potential impact
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.9
G.3 Vulnerability Assessment
The intent of this section is to assess the City’s vulnerability separately from that of the County as a whole, which
has already been assessed in Chapter 5 of the Base Plan. This vulnerability assessment analyzes the population,
property, and other assets at risk to hazards ranked of medium or high significance specific to the City.
The information to support the hazard identification and risk assessment was based on a combination of the
pervious previous LHMP for the City and jurisdiction specific information collected during the 2019 update. A
Local Hazard Mitigation Plan Update Guide and associated worksheets were distributed to each participating
municipality or special district to complete during the 2019 update process. Information collected was analyzed
and summarized in order to identify and rank all the hazards within the County , as well as to rank the hazards
and identify the related vulnerabilities unique to each jurisdiction.
Each participating jurisdiction was in support of the main hazard summary identified in the Base Plan (See Table
5.2). However, the hazard summary rankings for each jurisdictional annex may vary slightly due to specific hazard
risk and vulnerabilities unique to each jurisdiction (See Table G.7).
Note: The hazard “Significance” reflects overall ranking for each hazard and is based on the City of San Luis
Obispo LPT member input from the Data Collection Guide and the risk assessment developed during the
planning process (see Chapter 5 of the Base Plan), which included a more detailed qualitative analysis with best
available data.
The hazard summaries in Table G.7 reflect the hazards that could potentially affect City. The discussion of
vulnerability for each of the following hazards is located in Section G.3.2 Estimating Potential Losses. Based on
this analysis, the highest priority hazard (High Significance) for mitigation is Earthquake. Those of Medium or
High significance for the City of San Luis Obispo are identified below.
Adverse Weather: Thunderstorm/Heavy Rain/Hail/Lighting/Dense Fog/Freeze
Adverse Weather: High Wind/Tornado
Agricultural Pest Infestation and Disease
Biological Agents
Drought and Water Storage
Earthquake
Flood
Human Caused: Hazardous Materials
Wildfire
Other Hazards
Hazards assigned a significance rating of Low and which do not differ significantly from the County ranking (e.g.,
Low vs. High) are not addressed further in this plan. In the City of San Luis Obispo, those hazards are:
Landslide and Debris Flow
Adverse Weather: Extreme Heat
Subsidence
Additionally, the City’s HMPC members decided to rate several hazards as Not Applicable (N/A) to the planning
area due to a lack of exposure, vulnerability, and no probability of occurrence. Dam Incidents, Coastal
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.10
Storm/Coastal Erosion/Sea Level Rise, and Tsunami and Seiche Hazards are considered Not Applicable (N/A) to
the City of San Luis Obispo.
G.3.1 Assets at Risk
This section considers San Luis Obispo’s assets at risk, including values at risk, critical facilities and infrastructure,
historic assets, economic assets, and growth and development trends. The HMPC used a variety of data to define
a baseline against which all disaster impacts could be compared. If a catastrophic disaster was to occur in the
Planning Area, this section describes significant assets exposed or at risk in the City of San Luis Obispo.
Values at Risk
Parcel data was provided by ParcelQuest, a third-party service working alongside the San L uis Obispo County
Assessor’s Office to compile property information. This data provided the baseline for an inventory of the total
exposure of developed properties within the county and helps to ensure that the updated HMP reflects changes
in development. This data should only be used as a guideline to overall values in the City as the information has
some limitations. The most significant limitation is created by Proposition 13; instead of adjusting property
values annually, the values are not adjusted or assessed at fair market value until a property transfer occurs. As a
result, overall value information is likely low and does not reflect current market value of properties. It is also
important to note that in the event of a disaster, it is generally the value of the infrastructure or improvements to
the land that is of concern or at risk. Generally, the land itself is not a loss. Table G.8 shows the exposure of
properties (e.g., the values at risk) broken down by property type for the City of San Luis Obispo.
Table G.8 2019 Property Exposure for the City of San Luis Obispo by Property Types
Property Type Property
Count
Improved
Value Content Value Total
Value
Commercial 1,081 $1,023,078,842 $1,023,078,842 $2,046,157,684
Government/Utilities 168 $1,435,945 -- $1,435,945
Other/Exempt/Misc. 507 $189,186,968 -- $189,186,968
Residential 8,226 $1,896,071,588 $948,035,794 $2,844,107,382
Multi-Family Residential 2,885 $811,851,931 $405,925,966 $1,217,777,897
Mobile/Manufactured
Homes
156 $25,110,344 $12,555,172 $37,665,516
Residential: Other 963 $368,632,456 $184,316,228 $ 552,948,684
Industrial 42 $ 60,310,187 $90,465,281 $150,775,468
Vacant 55 $ 36,862,009 -- $36,862,009
Total 14,083 $4,412,540,270 $2,664,377,282 $7,076,917,552
Source: Wood analysis based on ParcelQuest and San Luis Obispo County Assessor’s Office data 2019.
Critical Facilities and Infrastructure
Critical Facilities are essential in providing utility or direction either during the response to an emergency or
during the recovery operation. These facilities typically include hospitals, fire stations, and local law enforcement
stations, and according to FEMA should be given special consideration when formulating regulatory hazard
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.11
mitigation and floodplain management plans. See Section 5.2 of the Base Plan for more details on the definition
s and categories of critical facilities.
A portion of the critical facilities data was provided by the San Luis Obispo County Planning & Building and GIS
Departments. Supplemental data from the Homeland Infrastructure Foundation -Level Data (HIFLD) was used to
capture additional facilities such as law enforcement facilities and centers, communications facilities, emergency
operations centers, schools, and urgent care facilities among others. In addition, participating jurisdictions
identified assets on a data collection guide worksheet or in previo us LHMPs which may capture additional
facilities and additional details not within the GIS database. An inventory of critical facilities in the City of San
Luis Obispo determined with San Luis Obispo County GIS data is provided in Table G.9 and illustrated in Figure
G.2.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.12
Figure G.2 Critical Facilities in the City of San Luis Obispo
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.13
Table G.9 City of San Luis Obispo’s Critical Facilities
Category Asset Name Asset IDs Address Replacement
Value Priority
Community and
Recreational
Facilities
City Hall 68 990 Palm St $9,287,080 Critical
Library 451 995 Palm St $1,604,146 Essential
Ludwick Community Center 452 864 Santa Rosa St $2,559,501 Critical
Meadow Park Recreational
Center 453 2333 Meadow St $1,448,126 Essential
Mitchell Park Senior Center 456 1445 Santa Rosa St $1,068,158 Essential
Sinsheimer Pool and Park 97-110 900 Southwood Dr $2,623,419 Essential
Infrastructure
Critical Bridges
10, 11, 19, 20,
23, 25, 27, 34,
35, 40, 41, 42,
44, 51, 56
Varies by bridge Varies by
bridge Critical
Essential Bridges
8, 9, 12-18, 21,
22, 24, 26, 28-
33, 36-39, 43,
45-50, 52-55,
58, 59-62
Varies by bridge Varies by
bridge Essential
Higuera Box Culvert 57 Higuera St $4,500,000 Critical
Evacuation Route Roads 50 miles $1 million/mile
50,000,000 Critical
Other Essential City-Owned
Roads 120 miles
1 million/mile
120,000,000
Essential
Communication Towers 614,616,617 N/A Essential
Other City-Owned
Facilities
City Corporation Yard 426 25 Prado Rd $4,884,929 Critical
Community Development and
Public Works Administration 437 919 Palm St $23,081,375 Essential
Parking Garage 477 Marsh and Chorro
St $22,873,449 Essential
Parking Garage 478 842 Palm St $8,795,686 Essential
Parks and Recreation Building 479 1341 Nipomo St $1,282,662 Essential
Prado Day Center 96 45 Prado Rd $699,393 Essential
Utilities Administration 541 879 Morro St $1,060,252 Essential
Police and Fire
Stations
Dispatch Center 78 1135 Roundhouse $6,701,098 Critical
Fire Station #1 69 2160 Santa Barbara $5,483,205 Critical
Fire Station #2 70 136 N Chorro St $511,872 Critical
Fire Station #3 71 1280 Laurel Ln $594,009 Critical
Fire Station #4 72 1395 Madonna Rd $507,087 Critical
Police Main Building, Garage,
Annex 73-77 1042 and 1016
Walnut St $4,854341 Critical
Potable Water
and Wastewater
Facilities
Fire Station #4 Well 619 1395 Madonna Rd N/A Essential
Pacific Beach Well 620 11950 LOVR N/A Essential
Reservoirs 63-67 N/A Essential
Sewer Lift Stations 555-564 N/A Essential
Sewer System Infrastructure
pipes) N/A Essential
Storm Drain System N/A Essential
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City of San Luis Obispo | February 2020 Annex G.14
Category Asset Name Asset IDs Address Replacement
Value Priority
Waste Water Treatment Plant
includes Water/Wastewater
Laboratory)
615 35 Prado Rd $77,296,765 Essential
Water Pump Stations 1-7 N/A Critical
Water System Infrastructure
pipes) N/A Critical
Water Tanks 566-613 N/A Critical
Water Treatment Plant and
Stenner Hydro Plant 565 Stenner Creek Rd $51,486,423 Essential
Source: San Luis Obispo County Planning & Building, HIFLD
High Potential Loss Facilities
High potential loss facilities are considered critical facilities that present significant risks if damaged and include
nuclear power plants, dams, and military installations. The City has one classified high potential loss facility: The
San Luis Obispo Wastewater Treatment Plant (WWTP). The WWTP is located within a 100-year floodplain and
within a moderate liquefaction risk zone; however, other potential hazard impacts are low.
Transportation and Lifeline Facilities
The City contains a network of roadways and public transportation including the Pacific Coast Railway . US
Highway 101, Highway 1, and State Route 227 (Broad Street) provide regional access to the City. The San Luis
Obispo County Regional Airport serves the City and is located in the southern portion of the jurisdiction.
Lifeline Utility Systems are defined as those systems necessary to provide electric power, natural gas, water and
wastewater, and other facilities and services that are essential to the well -being of the City. Lifeline utility
systems within the City include:
AM Transmission Towers (1)
FM Transmission Towers (1)
Microwave Service Towers (52)
Wastewater Treatment Plants (1)
Energy Commission Facilities (7)
Historic and Cultural Resources
The City of San Luis Obispo has a wealth of historic and culturally significant resources due to its rich and varied
history. Such resources represent the City’s diverse historical context from periods prior to Chumash settlement
and Spanish colonization, through early development and mid-century growth that established many of the
existing neighborhoods and set a precedent for community design. The City of San Luis Obispo Citywide Historic
Context Statement (2014) identifies various historical factors that shaped the development of the area, and
provides a framework for the continuing process of identifying historic, architectural, and cultural resources in
the City. The City has an active historic preservation program, and historic preservation is prioritized throughout
City policy. City Zoning Regulations also establish the Historical Preservation Overlay Zone, which describes the
allowed uses and property development standards within designated Historic Districts. Historic Districts within
the City include Downtown Commercial District, the Mill Street District, the Old Town Neighborhood, the Little
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City of San Luis Obispo | February 2020 Annex G.15
Italy District, the Monterey Heights District, the Mount Pleasanton/Anholm District, the Chinatown Historic
District, and the Railroad Districts.
Historical resources in the context of the City are also identified by the National Register of Historic Places
NRHP), the California Register of Historic Resources (CRHR), and the County of San Luis Obispo’s List of Historic
Resources in addition to local designation. Such resources are buildings, structures, objects, places, and areas
that have an association with important persons, events in history, or cultural heritage, or have distinctive
architecture, design or construction method. State and local registers of historic resources also identify Historical
Points of Interest that have primarily local significance and interest in preservation. The City of San Luis Obispo
has several registered national, state, and local sites of historic and cultural significance (Table G.10). County-
wide historic resources are further detailed in Chapter 5.2, Asset Summary, of the Base Plan.
Table G.10 Historic Places
Historic Site Register Date Listed Address
Ah Louis Store State/National 1965 800 Palm Street
Angel Myron House National 1982 714 Buchon St.
Corral de Piedra National 1978 S of San Luis Obispo on Price
Canyon Rd.
Dallidet Adobe State 1960 1185 Pacific Street
Jack Robert House National 1992 536 Marsh St.
Mission San Luis Obispo De
Tolosa State 1939 751 Palm Street
Monday Club of San Luis Obispo National 2016 1815 Monterey St.
Pacific Coast Railway Company
Grain Warehouse National 1988 65 Higuera St.
Pereira Octagon Barn National 2014 4400 Octagon Way
Port San Luis Site National 1978 Address Restricted
The Powerhouse National 1993
Junction of S/ Perimeter Rd. and
Cuesta Ave
Rancho Canada de los Osos y
Pecho y Islay National 1975 Address Restricted
San Luis Obispo Carnegie Library National 1995 696 Monterey St.
Tribune Republic Building National 1993 1763 Santa Barbara St.
William Shipsey House National 2010 1266 Mill St.
Camp San Luis Obispo State Point of
Interest 1990 NA
Hollister Adobe State Point of
Interest 1972 NA
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City of San Luis Obispo | February 2020 Annex G.16
Natural Resources
Natural resources are important to include in benefit-cost analyses for future projects and may be used to
leverage additional funding for projects that also contribute to community goals for protecting sensitive natural
resources. Awareness of natural assets can lead to opportunities for meeting multiple objectives. For instance,
protecting wetlands areas protects sensitive habitat as well as attenuates and stores floodwaters.
The City’s landscape is made up of creeks, hills, valleys, and rich farmland that supports a variety of plants and
animal species. The San Luis Obispo area contains a diverse array of naturally occurring biological communities
and extensive open space areas including the Irish Hills Natural Reserve, the Islay Hills Open Space, South Hills
Open Space, Charles A. and Mary R. Maino Open Space, Ferrini Ranch, and the Laguna Lake Park and Open
Space. The City’s many creeks provide sheltered corridors that allow wildlife to move between dispersed habitats
and open space areas.
Economic Assets
California Polytechnic State University is the largest employer in the City of San Luis Obispo with nearly 3,000
employees. San Luis Coastal Unified School District employs 384 regular classified employees. The industrial
sector including education services, healthcare, and social assistance are the largest employers in the City at
approximately 20.2% of the total employers. In 2007, approximately 5,127 individuals were employed in
educational services, health care, and social assistance jobs. The General Plan Land Use Element (LUE) for the
City includes policies to accommodate a maximum population of 57,200 persons. Assuming a 0.5% growth rate,
the City would reach the anticipated residential capacity by year 2057. Tourism is an increasing trend in the City
due to the diverse range of activities, small-town appeal and recent development of several hotels near and in
the downtown core. Loss of a major employer from a hazard impact would result in a significant rise in
unemployment and loss in sales tax revenue.
G.3.2 Estimating Potential Losses
Note: This section details vulnerability to specific hazards of high or medium significance, where quantifiable,
and/or where (according to HMPC member input) it differs from that of the overall County.
Table G.9 above shows San Luis Obispo’s exposure to hazards in terms of number and value of structures. San
Luis Obispo County parcel and assessor data were used to calculate the improved value of parcels. The most
vulnerable structures are those in the floodplain (especially those that have been flooded in the past),
unreinforced masonry buildings, and buildings built prior to the introduction of modern-day building codes.
Impacts of past events and vulnerability to specific hazards are further discussed below . (See Section 4.1 Hazard
Identification for more detailed information about these hazards and their impacts on the County as a whole.)
Adverse Weather: Thunderstorm/Heavy Rain/Hail/Lightning/Dense Fog/Freeze
Adverse weather in the City usually occurs as localized thunderstorms that bring heavy rains and strong winds,
most often during the winter and spring months. Heavy rain has historically produced extensive flooding in the
City. Dense fog can result in reduced visibility and slick road conditions that increase the likelihood for traffic
accidents. Freeze is rarely a threat to human life in the City, but has the potential to impact agricultural
operations where crop damage to high value products can be extensive. According to frost dates and
temperature data published by the University of California Agriculture & Natural Resources, the lowest recorded
temperature is 20 F, and average annual low temperatures of 42 to 43 F typically occur in January and
December.
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City of San Luis Obispo | February 2020 Annex G.17
Adverse Weather: High Wind/Tornado
The City is subject to strong southeasterly winds associated with strong cold fronts and coastal storms, which
generally occur during the winter months from November to February. Northwesterly winds that are typical of
the central coast of California also occur throughout San Luis Obispo during the spring and summer. Both
southeast and northwest wind events can reach sustained wind speeds of 35-45 mph with wind gusts of 65-75
mph within the City. Wind related events can have substantial destructive impacts, especially in urban areas
where falling trees and branches can result in considerable property damage. Tornadoes have historically
occurred in San Luis Obispo, with the first recorded tornado taking place in April 1926 due to a strong coastal
storm front from the Pacific. Recorded tornadoes since then have typically been low severity, and caused minor
damage such as broken tree branches and minor structural and roof damage to buildings. Refer to Section 5.3.1
Adverse Weather, in the Base Plan for analysis related to tree mortality in the County of San Luis Obispo.
Agricultural Pest Infestation and Disease
Agricultural pests and pathogens (insects, fungi, bacteria, viruses and invasive plants) cause injury or destruction
to crops or livestock. The prominent agricultural uses in San Luis Obispo County can be impacted by a wide
variety of invasive pests, which pose a significant threat to crops, economy, food su pply, and native habitat.
Biological Agents
Public health impacts due to biological agents are a recognized potential threat to the City. The City is largely
reliant on the County’s Emergency Preparedness Program, which supports the Public Health Departm ent in the
management and coordination of public health emergencies including natural disasters, technological disasters,
bioterrorism incidents, and pandemics. Food and waterborne illnesses are major health problems that present
significant health risks to the City as well as threats to regional food and water supply. The City supports and
participates in the County Public Health Department’s up-to-date Pandemic Influenza Plan and Strategic
National Stockpile Plan to facilitate prevention, early detection, and treatment to effectively respond to
pandemics.
Drought and Water Storage
Periods of drought can have significant environmental, agricultural, health, economic, and social consequences.
Prolonged drought has the potential to impact structures due to subsidence, and can reduce water quality due
to lower water flows and reduced pollutant dilution. The City recently experienced its third driest period on
record since 1870 when weather observations began at the San Luis Obispo Polytech Weather Station. Long -
term precipitation information from the station indicates the variability that can occur, which is summarized in
Figure 5-4 in Section 5.3.6 of the Base Plan. The City has invested in a multi-source water supply including
Nacimiento, Whale Rock, and Santa Margarita Reservoirs, groundwater, and recycled water for landscape
irrigation. Water demand modeling estimates that these sources provide a 7.5 year combine d water supply,
assuming an extended worst case historical drought.
Earthquake
Earthquake events have occurred in the City in the past, including a number of magnitude 5.0 to 7.0
earthquakes. Historically, most of the earthquakes that have occurred near the City have originated from
movement along the San Andreas Fault, which lies approximately 35 miles northeast of the City. The most recent
major earthquake to affect San Luis Obispo occurred at 11:15:56 am Pacific Standard Time on December 22,
2003. The epicenter of the magnitude 6.5 earthquake was approximately 7 miles northeast of San Simeon at a
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City of San Luis Obispo | February 2020 Annex G.18
depth of 4.7 miles (35.706N, 121.102W), 45 miles from San Luis Obispo. The City of San Luis Obispo experienced
some minor damage. The main strand of the Los Osos fault zone, also known as the Edna fault zone, traverses
the City near the intersection of Los Osos Valley Road and Foothill Boulevard. Field evaluations by the California
Geological Survey (CGS) for the main strand of the Los Osos fault found evidence of movement in the last 11,000
years. This evidence of recent activity resulted in the establishment of an Earthquake Fault Zone by CGS in 1989
under the Alquist-Priolo Fault Zoning Act. The Los Osos fault specifically presents a high to very high fa ult
rupture hazard to developments near and southwest of the Los Osos Valley Road area.
Table G.11 Seismic Hazard Designation by Property Type
Seismic Designation Property Type Property Count Improved Value
Los Osos Alquist-Priolo
Residential 28 $9,541,741
Residential: Other 2 $693,134
TOTAL 30 $ 10,234,875
Source: San Luis Obispo County Planning & Building, County Assessor’s Office, ParcelQuest, Wood Plc analysis
In addition to being at risk of groundshaking as a result of a fault rupture, the City of San Luis Obispo is also
susceptible to the effects of liquefaction. Most of the City is underlain by alluvium and other liquefiable
sediments that may present a risk of liquefaction during ground shaking; however, liquefaction risk is generally
classified as low to medium on a scale of very low to very high. Liquefaction risk is visually displayed across the
City under Figure G.4 below.
Table G.12 Parcels Susceptible to Moderate Liquefaction Risk
Parcel Type Parcel Count Improved Parcel Value
Commercial 992 $964,747,104
Government/Utilities 125 $1,435,945
Other/Exempt/Miscellaneous 418 $170,684,946
Residential 5,282 $1,076,982,642
Multi-Family Residential 2,387 $678,902,288
Mobile/Manufactured Homes 148 $16,744,811
Residential: Other 673 $272,473,739
Industrial 36 $55,659,992
Vacant 42 $31,483,257
TOTAL 10,103 $3,269,114,724
Source: San Luis Obispo County Planning & Building, County Assessor’s Office, ParcelQuest, Wood Plc analysis
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City of San Luis Obispo | February 2020 Annex G.19
Figure G.3 Seismic Hazard Designation in the City of San Luis Obispo
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City of San Luis Obispo | February 2020 Annex G.20
Figure G.4 Liquefaction Risk in the City of San Luis Obispo
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City of San Luis Obispo | February 2020 Annex G.21
Flood
In San Luis Obispo, the most common type of flooding event is riverine flooding, also known as overbank
flooding. Riverine floodplains range from narrow, confined channels in the steep valleys of mountainous and
hilly regions, to wide, flat areas in plains and coastal regions. The amount of water in the floodplain is a function
of the size and topography of the contributing watershed, the regional and local climate, and land use
characteristics. Flooding in steep, mountainous areas is usually confined, strikes with less warning time, and has a
short duration. Larger rivers typically have longer, more predictable flooding sequences and broad floodplains.
In addition to riverine flooding, San Luis Obispo is susceptible to flash flooding. Flash flood is a term widely used
by experts and the general population, but no single definition or clear means of distinguishing flash floods from
other riverine floods exists. Flash floods are generally understood to involve a rapid rise in water level, high
velocity, and large amounts of debris, which can lead to significant damage that includes the tearing out of
trees, undermining of buildings and bridges, and scouring of new channels. The intensity of flash flooding is a
function of the intensity and duration of rainfall, steepness of the watershed, stream gradients, watershed
vegetation, natural and artificial flood storage areas, and configuration of the streambed and floodplain. Urban
areas are increasingly subject to flash flooding due to the removal of vegetation, installation of impermeable
surfaces over ground cover, and construction of drainage systems. Wildfires that strip hillsides of vegetation and
alter soil characteristics may also create conditions that lead to flash floods and debris flows. Debris flows are
particularly dangerous due to the fact that they generally strike without warning and are accompanied by
extreme velocity and momentum. Dam failure may also lead to flash flooding; however, the County’s dam
inundation as well as the California Office of Emergency Services dam inundation data confirms that there are no
dam inundation zones located within the City limits.
The most serious flood events on record resulting in property damage or loss of life in San Luis Obispo occurred
in 1868, 1884, 1897, 1911, 1948, 1952, 1962, 1969, 1973, 1993, 1995, 1998 , and 2001. Recent damaging floods
occurred during January and March of 1995, with a lesser flooding problem in 1998. Flow during these events
overtopped streambanks near the intersection of Marsh and Higuera Streets and remained out of the channel
for nearly three miles downstream, with damage estimated at nearly $2.3 million. The City and Zone 9 spent
approximately $1 million to repair bank erosion caused during the winter of 1995. Damage occurred near the
town of Avila during both the January and March 1995 events, where high flow and debris blockages caused
extensive damage to several bridges across the creek. Flooding during 1969 was significantly damaging ; two
floods occurred, one at the end of January and the second at the end of February. During this two-month
period, a local rain gage recorded an accumulated precipitation total of 39.79 inches. Historically, the 1969 and
1973 events were more damaging than the 1 995 floods in present day dollars. The 1969 flood caused
approximately $6.92 million in damage within the SLO Creek watershed. The 1973 storm caused $13.6 million
along Stenner Creek, Brizziolari Creek, Prefumo Creek, and See Canyon Creek.
See Figure G.5 below illustrating the parcels at risk of flooding during a 100- or 500-year event based on the
FEMA flood hazard areas.
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City of San Luis Obispo | February 2020 Annex G.22
Table G.13 100-Year and 500-Year Flooding by Jurisdiction and Parcel Type
Parcel Type Parcel
Count
Improved
Value
Content
Value Total Value Loss
Estimate Population
100-YEAR FLOOD EVENT
Commercial 307 $ 310,143,384 $ 310,143,384 $ 620,286,768 $155,071,692 --
Government/Utilities 29 $ 10,050 -- $10,050 $2,513 --
Other/Exempt/Miscellaneous 75 $ 29,586,337 -- $29,586,337 $7,396,584 --
Residential 338 $71,676,715 $35,838,358 $ 107,515,073 $26,878,768 848
Multi-Family Residential 209 $66,889,696 $33,444,848 $ 100,334,544 $25,083,636 525
Mobile/Manufactured Homes 5 $591,404 $ 295,702 $887,106 $221,777 13
Residential: Other 25 $ 42,055,551 $21,027,776 $63,083,327 $15,770,832 63
Industrial 6 $ 2,632,168 $3,948,252 $6,580,420 $1,645,105 --
Vacant 11 $2,988,322 -- $2,988,322 $ 747,081 --
TOTAL 1,005 $526,573,627 $ 404,698,319 $ 931,271,946 $232,817,987 1,448
500-YEAR FLOOD EVENT
Commercial 111 $74,714,129 $74,714,129 $ 149,428,258 $37,357,065
Government/Utilities 8 -- -- $0 $0 --
Other/Exempt/Miscellaneous 35 $ 19,148,234 -- $19,148,234 $4,787,059 --
Residential 971 $ 190,774,098 $95,387,049 $ 286,161,147 $71,540,287 2,437
Multi-Family Residential 297 $66,546,672 $33,273,336 $99,820,008 $24,955,002 745
Mobile/Manufactured Homes 1 $245,631 $ 122,816 $368,447 $92,112 3
Residential: Other 51 $ 35,270,066 $17,635,033 $52,905,099 $13,226,275 128
Industrial 1 $312,120 $ 468,180 $780,300 $195,075 --
TOTAL 1,475 $387,010,950 $ 221,600,543 $ 608,611,493 $152,152,873 3,313
GRAND TOTAL 2,480 $913,584,777 $ 626,298,862 $1,539,883,439 $ 384,970,860 4,761
Source: San Luis Obispo County Planning & Building, County Assessor’s Office, ParcelQuest, Wood Plc analysis, FEMA NFHL
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City of San Luis Obispo | February 2020 Annex G.23
Figure G.5 Flood Hazard Areas and Flooded Parcels in the City of San Luis Obispo
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City of San Luis Obispo | February 2020 Annex G.24
Insurance Coverage, Claims Paid, and Repetitive Losses
The City of San Luis Obispo has been a participant in the National Flood Insurance Program since April 16, 1979,
and will continue to participate and remain in compliance with the National Flood Insurance Program (NFIP).
Table G.14 City of San Luis Obispo NFIP Insurance Policy Information
Policies
Insurance in
Force
No. of Paid
Losses
Total Losses
Paid
736 $223,380,300 83 $456,370
Source: FEMA National Flood Insurance Program Community Information System
FEMA Community Information System shows that as of April 2019 the City of San Luis Obispo has two Repetitive
Loss (RL) properties and no Severe Repetitive Loss (SRL) properties.
Table G.15 City of San Luis Obispo Repetitive Loss
Repetitive Loss
Properties
Insured
Properties
Repetitive Loss
Payments (tota)
2 1 $54,204.80
Source: FEMA National Flood Insurance Program Community Information System
The City of San Luis Obispo joined the Community Rating Systm (CRS) on October 1, 1991. Currenlty the City has
a Class 6 rating.
Critical Facilities at Risk
Critical facilities are those community components that are most needed to withstand the impacts o f disaster as
previously described. There are eight critical facilities found in the 100-year floodplain in San Luis Obispo, and
five critical facility located in the City’s 500-year floodplain. It is particularly important to note that the critical
facilities in the 500-year floodplain are all facilities that serve vulnerable populations and should be given special
attention. Table G.16 below summarizes the critical facilities in the City’s 100- and 500-year floodplains. The
impact to the community could be great if these facilities are damaged or destroyed during a flood event.
Table G.16 Critical Facilites in FEMA Flood Hazard Areas, City of San Luis Obispo
Floodplain Critical Facility Type Facility Count
100-year
Colleges / Universities 1
Day Care Facilities 1
Microwave Service Towers 3
Nursing Homes 1
VA Medical Facilities 1
Wastewater Treatment Plant 1
500-year
Colleges / Universities 1
Day Care Facilities 1
Microwave Service Towers 1
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City of San Luis Obispo | February 2020 Annex G.25
Floodplain Critical Facility Type Facility Count
Nursing Homes 1
Private Schools 1
TOTAL 13
Source: San Luis Obispo County Planning and Building Dept., LAFCO, HIFLD, Wood Plc Parcel Analysis, FEMA NFHL
Wildfire
The risk of wildland fires is greatest near the City limits where development meets rural areas of combustible
vegetation. Most of the community is within one mile of a High or Very High Fire Hazard Severity Zone, which
indicates significant risk to wildland fire. The City of San Luis Obispo is confronted with one of the more
hazardous wildfire risks in the County due to its location near the foothills of the Santa Lucia Mountains and the
Irish Hills, with increased wildfire risk in these foothills as well as on Chumash Peak, Bishop Peak, Cerro San Luis,
and Islay Hill. Figure G.6 illustrates, in map form, the wildfire hazard severity zones that cross over into the City
and hence pose risk to the community and its people.
Table G.17 Properties Within Moderate and Very High Wildfire Hazard Severity Zones
Parcel Type Parcel
Count
Improved
Value
Content
Value
Total
Value
Loss
Estimate Population
MODERATE WILDFIRE HAZARD SEVERITY
Commercial 1 $ 2,392,765 $2,392,765 $4,785,530 $4,785,530 --
Government/Utilities 1 -- -- $0 $0 --
Other/Exempt/Miscellaneous 1 -- -- $0 $0 --
Residential 3 $218,358 $109,179 $327,537 $327,537 8
TOTAL 6 $ 2,611,123 $2,501,944 $5,113,067 $5,113,067 8
VERY HIGH WILDFIRE HAZARD SEVERITY
Other/Exempt/Miscellaneous 2 -- $2 $2 --
Residential 14 $7,928,870 $3,964,435 $11,893,319 $11,893,319 35
Vacant 1 $40,500 -- $40,501 $40,501 --
TOTAL 17 $7,969,370 $3,964,435 $11,933,822 $11,933,822 35
GRAND TOTAL 23 $ 10,580,493 $6,466,379 $17,046,889 $17,046,889 43
Source: San Luis Obispo County Planning & Building, County Assessor’s Office, ParcelQuest, Wood Plc analysis, CalFire
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City of San Luis Obispo | February 2020 Annex G.26
Figure G.6 Wildfire Hazard Severity Zones
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City of San Luis Obispo | February 2020 Annex G.27
Human Caused: Hazardous Materials
The Cal OES Warning Center reports 419 hazardous materials incidents in the City of San Luis Obispo from 1994
through October 24, 2018; as noted in Section 5.3.13 of the county plan, this likely excludes a large number of
unreported minor spills. This constitutes 23% of the hazardous materials incidents reported countywide during
the same time frame, and averages out to roughly 16.8 incidents per year. As noted in Section 5.3.13, only
around 6% of reported hazardous materials incidents result in injuries, fatalities, or evacuations.
There is one CalARP regulated facilities and no EPA Risk Management Plan (RMP) facilities located in the City.
Additionally, the City sits within the Emergency Planning Zone for the Diablo Canyon Nuclear Power Plant .
G.4 Capability Assessment
Capabilities are the programs and policies currently in use to reduce hazard impacts or that could be used to
implement hazard mitigation activities. This capability assessment is divided into six sections: regulatory
mitigation capabilities, administrative and technical mitigation capabilities, fiscal mitigation capabilities,
mitigation outreach and partnerships, other mitigation efforts, and opportunities for enhancement.
To develop this capability assessment, the jurisdictional planning representatives used a matrix of common
mitigation activities to inventory policies or programs in place. The team then supplemented this inventory by
reviewing additional existing policies, regulations, plans, and programs to determine if they contributed to
reducing hazard-related losses.
During the plan update process, this inventory was reviewed by the jurisdictional planning representatives and
Wood consultant team staff to update information where applicable and note ways in which these capabilities
have improved or expanded. In summarizing current capabilities and identifying gaps, the jurisdictional planning
representatives also considered their ability to expand or improve upon existing policies and programs as
potential new mitigation strategies. The City of San Luis Obispo’s updated capabilities are summarized below.
G.4.1 Regulatory Mitigation Capabilities
Table G.18 City of San Luis Obispo Regulatory Mitigation Capabilities
Regulatory Tool
ordinances, codes, plans) Yes/No Comments
General Plan Yes
Land Use Element, Circulation Element, Housing Element, Noise
Element, Safety Element, Conservation and Open Space Element,
Parks and Recreation Element, and Water and Wastewater Element
Zoning ordinance Yes Title 17: Zoning Regulations of the City of San Luis Obispo
Municipal Code
Subdivision ordinance Yes Title 16: Subdivisions, Subdivision Regulations
Growth management ordinance Yes Chapter 17.144: Residential Growth Management Regulations
Floodplain ordinance Yes Chapter 17.78: Flood Damage Prevention
Other special purpose ordinance
stormwater, steep slope, wildfire) Yes
Ordinance 1543: Chapter 12.08 Urban Storm Water Quality
Management and Discharge Control
Ordinance 1490: Chapter 16.20 Physical Improvement Standards
and Procedures - 16.20.040 Grading plan
Ordinance 1490: Chapter 16.18 General Subdivision Design
Standards
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.28
Regulatory Tool
ordinances, codes, plans) Yes/No Comments
Chapter 17.70.090: Hillside Development Standards
Ordinances 1630 (part) and 1595 (part), Chapter 15.04 Construction
and Fire Prevention Regulations
A Stormwater Control Plan is required to be submitted for all
projects to demonstrate exemption or level of compliance required.
Post Construction Regulation outlines Stormwater Control Plan
content in Performance Requirement 2 - Sections B.3.c,
Performance Requirement 3 - Section B.4.g, and Performance
Requirement 4 – Section B.5.b. Through the Stormwater Control
Plan submittal, applicants demonstrate compliance with Post
Construction Requirements or exemption status.
Drainage Design Manual (Design Manual) has been developed to
provide criteria and planning procedures for floodplains,
waterways, channels, and closed conduits in the San Luis Obispo
Creek watershed. This Drainage Manual will be used by the City of
San Luis Obispo and San Luis Obispo County Flood Control and
Water Conservation District Zone 9 (SLO/Zone 9) staff in their
internal design of stormwater drainage, flood management and
bank stabilization and restoration projects.
Building code Yes
Title 15, Buildings and Construction of the City of San Luis Obispo
Municipal Code. California Building Codes:
CA Residential Code (2016); CA Plumbing Code (2015 UPC); CA
Mechanical Code (2015 UMC); CA Electrical Code (2014 NEC); CA
Energy Code (2016); CA Green Building Code (2016); CA Fire Code
2015 IFC); CA Reference Standards Code (2016)
Fire department ISO rating Yes 2
Erosion or sediment control program Yes
Chapter 17.78 Flood Damage Prevention
Chapter 12.08 Urban Storm Water Quality Management and
Discharge Control
Chapter 16.20 Physical Improvement Standards and Procedures
Ordinance 1543, Code Section 12.08.150 Requirement to prevent,
control, and reduce storm water and pollutants
City of SLO Waterway Management Plan and Drainage Design
Manual
Annual silt removal to maintain hydraulic capacity in San Luis
Obispo creek beds to reduce flooding. City has 14 total sites in the
management plan and complete silt removal on a rotating basis.
Stormwater management program Yes Chapter 12.08: Stormwater Regulations & Requirements
Site plan review requirements Yes Title 22 Article 3
Capital improvements plan Yes Department of Public Works 5-Year Strategic Plan
Economic development plan Yes 5-Year Economic Development Strategic Plan Updated in 2015
Local emergency operations plan Yes City of San Luis Obispo Emergency Operations Plan (2011)
Other special plans Yes
Open Space Conservation Plans, Climate Action Plan, Urban Water
Management and Water Shortage Contingency Plans, Waterway
Management Plan, Utilities Department Emergency Plan,
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San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.29
Regulatory Tool
ordinances, codes, plans) Yes/No Comments
Unreinforced Masonry Hazard Mitigation Program, Disaster
Preparedness Program, Community Wildfire Preparedness Plan,
Greenbelt Protection Program
Flood insurance study or other
engineering study for streams Yes 2012
Elevation certificates (for floodplain
development) Yes Chapter 17.78: Flood Damage Prevention
Other Yes
Water System Vulnerability Assessment, Floodplain Management
Educational Program
G.4.2 Administrative/Technical Mitigation Capabilities
There are several key departments and staff within the City organization that serve a specific role in developing
and implementing hazard mitigation activities. City government consists of approximately 399 full-time
equivilent employees and 10 departments: Police, Fire, Public Works, Public Utilities, Community Development,
Parks and Recreation, Human Resources, Finance and Information Technology, City Administration, and the City
Attorney’s Office. With a clear set of policies in place and a diverse range of staff available to mitigate identified
hazards within the City, the City has many staff with specific training on the use of specialized equipment or
particular areas of expertise that are essential in implementing mitigation actions. Technical resources are
considered to be physical infrastructure or equipment available to the City to aid in implementing hazard
mitigation or disaster response activities. Table G.19 identifies the personnel resources and technical resources
that increase capabilities related to mitigation and loss prevention in the City.
Table G.19 City of San Luis Obispo Administrative/Technical Mitigation Capabilities
Personnel Resources Yes/No Department/Position
Planner/engineer with knowledge of
land development/land management
practices
Yes Staff with knowledge of land development practices and local land
development patterns.
Engineer/professional trained in
construction practices related to
buildings and/or infrastructure
Yes Professionals trained in construction practices associated with
buildings and infrastructure and in storm water compliance during
construction and operation of buildings and infrastructure projects.
Planner/engineer/scientist with an
understanding of natural hazards
Yes
Personnel skilled in GIS
Yes Provide accurate and comprehensive Geographic Information
System for managing resources, make informed decisions, and
expedite work processes.
Full time building official Yes Community Development Department, Chief Building Official
Floodplain manager Yes Community Development Department, Supervising Civil Engineer
Emergency manager
Yes Accomplished through contract services. City maintains funding for
the 2019-21 Financial Plan to maintain an Emergency Manager
position equivalent to 0.5 FTE.
Grant writer
Yes Accomplished through Contract Services. The City maintains two-
year contracts with both a local grant writing firm and grant
advocate firm based out of Irvine, CA.
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San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.30
Personnel Resources Yes/No Department/Position
Mutual Aid Agreements
Yes Establishes agreements among local jurisdictions to assist in
emergency response efforts in neighboring jurisdictions during
times of need. San Luis Obispo currently participates in the
following mutual aid agreements: 1. California Master Mutual Aid
Agreement, 2. SLO County Fire and Rescue Mutual Aid Agreement,
3. California Fire Assistance Agreement, 4. Region 1A Law
Enforcement Mutual Aid Agreement, 5. Public Works Mutual Aid
Agreement, 6. California Emergency Managers Mutual Aid
Agreement, 7. Regional Disaster Medical/Health Coordination.
Code Enforcement and Neighborhood
Services
Yes Staff with training and expertise in identifying hazards to health,
safety, and welfare, and assisting property owners with achieving
code and policy compliance.
Fire Marshal
Yes Measure G funded position, manages and directs the activities of
the Fire Prevention Bureau. Oversees fire safety inspections for all
facilities in the City. Ensures that development in the City meets fire
safety standards. Obtains funding and implements wildland fuel
reduction projects. Directs and oversees fire investigations.
Fire Inspectors
Yes Professionals trained in fire prevention techniques and construction
practices associated with buildings and infrastructure. Inspect all
multi-family residential buildings and public assembly buildings.
Review building plans and inspect construction projects for fire and
life safety and proper installation of fire protection systems.
Investigate fire for cause and origin.
Hazardous Materials Coordinator
Staff designated to inspect facilities and containers storing
hazardous materials. There are approximately 244 facilities located
within the City that are permitted for the use of hazardous
materials.
Network Administrators Yes Provide technical support for wired/wireless network and radios.
Park Rangers Yes Staff familiar with brush clearance requirements and conditions of
City-owned open space.
Police Officers
Yes Emergency response to provide protection of life, property and
address community safety/security needs. Work cooperatively with
other first responders for an organized response to disaster
mitigation plans.
Dispatchers Yes Provide communication links to responding personnel to transfer
emergency information and direct resources as needed.
Construction Inspection Yes Ensures storm water compliance during construction of City
projects, and private grading and encroachment projects.
Public Works Department – Department
Operations Centers (DOC)
Yes The Public Works DOC coordinates responses to road flooding and
related problems during a storm with road crews, the County,
Caltrans, and the California Highway Patrol. They also support other
emergency response operations coordinated through the City’s
EOC.
Storm Water Compliance
Yes Staff responsibility assigned to ensure storm water compliance
during construction and operation of buildings and infrastructure
projects.
Other personnel Yes Operations: Field staff provide assistance to Public Works DOC for
flood response, and City EOC for general emergency response.
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San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.31
Personnel Resources Yes/No Department/Position
GIS Data Resources
Hazard areas, critical facilities, land use,
building footprints, etc.)
Yes
Warning systems/services
Reverse 9-11, outdoor warning signals)
Yes
Voluntary Organizations Active in
Disaster
Yes Provides disaster preparedness courses to residents and
community members and provides care and shelter to those
threatened or impacted by natural hazards. Volunteer and private
agencies are essential to the area’s mutual aid system by providing
for the care and shelter needs of disaster victims. Organizations
active in San Luis Obispo include the American Red Cross and
Salvation Army.
G.4.3 Fiscal Mitigation Capabilities
There are multiple financial and funding opportunities for the City to mitigate or respond to natural hazards.
These capabilities include local revenues from the general fund, or the receipt of grant funds from state or
federal agencies. The City’s financial planning process includes a two-year goal setting and budget development
based on community and council priorities. The City’s five-year fiscal forecast identifies the City’s forecast of
revenues, expenditures, and changes in fund balance. The general fund receives revenues from a variety of
sources including taxes (sales, property, transient occupancy, business, utility users), subventions and grants
vehicle license fees, gas tax, and other subventions), service charges (development review fees, recreation fees),
and other revenues (fines, interest earnings, and rents). The City has and will continue to utilize the two -year
goal setting and budget process to prioritize expenditures needed to mitigate future hazards. In the event of a
natural disaster and a need for immediate City response, the City has the financial capacity to utilize reserve
funds, when authorized by the City Council. The City has previously utilized the following financial resources to
implement hazard mitigation activities. The added revenues to the General Fund from Measure “G” have allowed
the City to financially support major improvements in the areas of public safety, flood protection, and open
space preservation. Financial resources to mitigate hazards: Table G.20 identifies financial tools or resources that
the City could potentially use to help fund mitigation activities.
Table G.20 City of San Luis Obispo Fiscal Mitigation Capabilities
Financial
Resources
Accessible/Eligible
to Use (Yes/No)
Comments
Community
Development
Block Grants
Yes
The City continues to seek grant opportunities through the CDBG
program and identify potential eligible projects that would fund
mitigation activities to benefit the health and welfare of the community.
Capital
improvements
project funding
Yes
The Capital Improvement Plan (CIP) enables the City to plan, schedule,
and finance capital projects to ensure cost effectiveness and conformance
with established plans and policies. The City’s budget process guides the
capital priorities through community input, Council goal setting, Local
Revenue Measure priorities, and the biennially adopted Major City Goal
work programs. The City’s CIP includes all planned infrastructure projects
over a five-year period. The first two years identify those projects that are
planned to be funded and/or completed during the adopted two-year
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City of San Luis Obispo | February 2020 Annex G.32
Financial
Resources
Accessible/Eligible
to Use (Yes/No)
Comments
financial plan. The latter three years serve as the framework for future
Financial Plans’ capital budgets. The plan represents a phased approach to
funding the projects needed to maintain the City’s infrastructure and
major facilities over the entire five-year period.
Authority to levy
taxes for specific
purposes
Yes
Taxes for specific purposes can be levied with authorization from the City
Council and further approval through a local ballot measure.
Fees for water,
sewer, gas, or
electric services
Yes
The City's utilities department provides water and wastewater services to
the residents and businesses of San Luis Obispo. Water and sewer
revenues are collected to support operations and capital improvements,
with rates reviewed on an annual basis and approved by the City Council.
These revenues from customer water and sewer use are utilized by the
utilities department to maintain, improve, expand and replace
components of the City's water and wastewater infrastructure system,
including improvements made to protect from natural hazards.
Impact fees for
new development Yes
New development projects proposed in the City affect the City's ability to
provide adequate essential services (e.g. transportation, water and
wastewater, and open space). To ensure these essential services can
adequately serve the City's existing and future community needs, a series
of development impact fees are levied on new development projects.
Incur debt
through general
obligation bonds
Yes
Debt can be incurred through general obligation bonds with authorization
from the City Council and further approval through a local ballot measure.
Incur debt
through special
tax bonds
Yes
Debt can be incurred through special tax bonds with authorization from
the City Council and further approval through a local ballot measure.
Incur debt
through private
activities
Yes
City Financial Policy allows debt to be incurred through private activities
with approval from City Council
Withhold
spending in
hazard prone
areas
Yes
Policy is accessible with authorization from City Council.
General Fund
including
Measure G
Funding)
Yes
In 2006, City voters approved measure Y to preserve and enhance
essential City services by establishing a 1/2 –cent City sales tax. In the
2011/12 fiscal year, measure Y generated approximately $6.2 million in
revenue. This funding has been used in recent years for public safety,
infrastructure maintenance, traffic congestion relief, neighborhood code
enforcement and open space acquisition project. Many of the projects
funded through measure Y revenues are considered to help mitigate
hazard throughout the community. In 2014 Measure Y was approved to
be extended through ballot measure G, which will sunset in 2022 unless a
new measure is passed to continue the collection of additional sales tax.
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City of San Luis Obispo | February 2020 Annex G.33
Financial
Resources
Accessible/Eligible
to Use (Yes/No)
Comments
Reserve Funds Yes
The City’s budget and fiscal policies includes a requirement to maintain
adequate fund reserves for both general and enterprise funds. The
minimum reserve level is 20% of annual operating expenditures.
Building Permit
Inspection and
Review Fees
Yes
Fees are collected by the planning and building divisions of the
community development department to inspect and review construction
documents on proposed projects within the City. The collection of these
fees ensures buildings are designed and constructed in a manner
consistent with applicable components of the municipal code and helps
the department to recover staff costs associated with review and
inspection.
G.4.4 Mitigation Outreach and Partnerships
Throughout the planning process of the Multi-jurisdictional HMP, the City participated in local outreach by
promoting public meetings and circulating the Public Draft of the HMP for public comment and review . Public
comments have been addressed and have been incorporated into the final HMP, where applicable. To further
support implementation of hazard mitigation activities, the City has established strong partnerships with its
neighboring jurisdictions, San Luis Obispo County, and multiple state organizations such as the California
Highway Patrol, Cal Poly, CalFire, and Caltrans to collectively address local hazards. These partnerships have
been formalized through the following:
Mutual Aid Agreements
Voluntary Organizations Active in Disaster
San Luis Obispo County Community Fire Sage Council
Department Operations Centers (DOC)
The City of San Luis Obispo also coordinates with many external (local, state, federal, and private sector)
agencies which have capabilities to support hazard mitigation activities. Many of these agencies participated in
the hazard mitigation planning process to update this plan, including the following:
County of San Luis Obispo – Airports
County of San Luis Obispo – Office of Emergency Services
County of San Luis Obispo – Public Health Department
Cal Poly – City & Regional Planning Department
Cal Poly – Administration and Finance
French Hospital Medical Center
American Red Cross
Sierra Vista Regional Medical Center
San Luis Coastal Unified School District
California Highway Patrol
Pacific Gas and Electric Company (PG&E)
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City of San Luis Obispo | February 2020 Annex G.34
G.4.5 Other Mitigation Efforts
In addition to the plan and policy resources available to the City to mitigate hazards, the City has developed or
participated in several hazard mitigation programs including:
Unreinforced Masonry Hazard Mitigation Program
Disaster Preparedness Program
Floodplain Management Educational Program
San Luis Obispo Chamber of Commerce Business Continuity Planning
County Public Health Emergency Preparedness Advisory Committee
National Flood Insurance Program (NFIP) and FEMA Repetitive Loss Pr operties
Community Wildfire Protection Program
Greenbelt Protection Program
G.4.6 Opportunities for Enhancement
Based on the capability assessment, the City has several existing mechanisms in place that help to mitigate
hazards. There are also opportunities for the City to expand or improve on these policies and programs to
further protect the community. Future improvements may include providing training for staff members related
to hazards or hazard mitigation grant funding in partnership with the County and Cal OES. Additional training
opportunities will help to inform City staff members on how best to integrate hazard information and mitigation
projects into their departments. Continuing to train City staff on mitigation and the hazards that p ose a risk to
the City will lead to more informed staff members who can better communicate this information to the public.
The following themes or opportunities were identified during the planning process of the 2014 LHMP:
Actions to Prepare – While many members of the community have taken small actions to prevent damage to
their home in the event of a natural hazard, only a small portion have completed larger structural items to
prevent damage. The City may consider developing and implementing programs to support risk reduction
activities by property owners. Using the data available as a result of the risk assessment in this HMP, the City
is able to identify areas and structures with a higher risk or exposure to the identified hazards. Sharing this
information with community members and evaluating opportunities to help property owners in funding risk
reduction activities will increase the resiliency of San Luis Obispo.
Awareness of Neighbor Needs – Given the high student population and regular turnover of neighbors in
some neighborhoods, it can be challenging for community members to be fully aware of neighbors and
their needs. Neighborhood events such as the annual community block parties are an opportunity for the
City to support greater community interaction which can increase awareness of neighbors needs in the
event of an emergency.
Community or Workplace Awareness – In many cases, respondents were unaware or unsure of the hazards
that may affect the community or their workplace and policies that may be i n place to help respond to a
natural disaster. The City can help to increase community awareness through wider promotion or
participation in workshops or resources available to the community that have already been prepared by the
City or volunteer organizations. The City may increase business owners’ awareness of risk by providing
emergency planning support, continuity of operations planning support, and potentially hosting seminars
for the business community to learn about the hazard risks.
Understanding the Extent of Damages – To better understand the extent of damages to homeowners from a
natural disaster, the City could coordinate with homeowner insurance providers to track damages beyond
those reported through the National Flood Insurance Program (NFIP).
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City of San Luis Obispo | February 2020 Annex G.35
G.5 Mitigation Strategy
G.5.1 Mitigation Goals and Objectives
The City of San Luis Obispo Planning Team determined the two goals from the 2014 LHMP continue to be
appropriate for this plan update, with the addition of a third goal to address hazards exacerbated by the impacts
of climate change. The following are the City of San Luis Obispo’s 2019 mitigation goals:
Goal 1: Cultivate a disaster-resistant and resilient community through implementation of risk reduction
measures and increased public awareness to prepare for, respond to, and recover from natural and human -
caused hazard events.
Objective 1.A Ensure that local plans, policies, and programs are consistent with the hazard information
identified in the LHMP.
Objective 1.B Increase City employee capacity through SIMS and NIMS compliant training and EOC
drills to identify hazards, and assist in emergency preparedness, response, and recovery.
Objective 1.C Pursue available grant funding to implement hazard mitigation efforts.
Objective 1.D Maintain critical and essential key assets to increase resiliency and minimize future
damage from hazard events.
Objective 1.E Increase public awareness of hazards, emergency response, and recovery.
Objective 1.F Promote public/private partnerships to increase community resiliency.
Goal 2: Reduce the severity of damage and losses due to natural and human-caused hazards.
Objective 2.A Protect and enhance, as practical, existing assets, as well as any future development, from
the effects of natural and human-caused hazards.
Goal 3: Prepare for and adapt to the impacts of climate change.
Objective 3.A Use, and update as needed, the best available science to estimate exposure, vulnerability,
and risk of hazards as the result of climate change.
Objective 3.B Use the climate change exposure, vulnerability, and risk assessments to ensure mitigation
investments, capital projects, and programs actively mitigate climate impacts.
Continued Compliance with the National Flood Insurance Program (NFIP)
The City has been an NFIP participating community since 1973 and will continue to comply with the NFIP. This
includes ongoing activities such as enforcing local floodplain development regulations, including issuing permits
for appropriate development in Special Flood Hazard Areas and ensuring that this development is mitigated in
accordance with the regulations. This will also include periodic reviews of the floodplain ordinance to ensure that
it is clear and up to date and reflects new or revised flood hazard mapping. The goals of the NFIP are to reduce
future flood damage through floodplain management and to provide people in participating communities with
flood insurance. Community participation is voluntary. The City is also part of the Community Rating System
CRS), currently rated at Class 7. The goals of the CRS are to reduce flood damages to insurable property,
strengthen and support the insurance aspects of the NFIP, and encourage a comprehensive appr oach to
floodplain management. The City of San Luis Obispo maintains full compliance with the NFIP through Sections
17.84.010- 17.84.170 within Chapter 17.84 Flood Damage Prevention Regulations of the San Luis Obispo
Municipal Code, which sets forth means to reduce losses from floods. These standards focus on areas located
within or near the 100-year floodplain. Section 8.12.010-8.12.010 of the Municipal Code provides a mechanism
for the City to require the removal of dangerous obstructions in streambeds th at have the potential to obstruct
water flow.
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City of San Luis Obispo | February 2020 Annex G.36
FEMA insures properties against flooding losses through the NFIP. As part of the process to reduce or eliminate
repetitive flooding to structures across the United States, FEMA has developed an official Repetit ive Loss
Strategy. The purpose behind the national strategy is to identify, catalog, and propose mitigation measures to
reduce flood losses due to the relatively few structures that represent the majority of claims from the National
Flood Insurance Fund. A Repetitive Loss property is defined by FEMA as a “property for which two or more NFIP
losses of at least $1,000 each have been paid within any 10-year period since 1978.” The City of San Luis Obispo
has two Repetitive Loss properties. As a CRS requirement, the City Public Works Department sends community
outreach notifications and letters to property owners in repetitive loss areas, including the City’s Mid Higuera
Area, to inform residents of flooding and to offer ways in which property owners can prepare for and reduce the
damage from repetitive flooding. In addition, the Public Works Department conducted storm drain
improvements as part of a Capital Improvements Project that helped with flood control in the Mid Higuera Area,
an area of repetitive flooding. FEMA also defines Severe Repetitive Loss properties; however, the City does not
have any Severe Repetitive Loss properties.
G.5.2 Completed 2014 Mitigation Actions
During the 2019 planning process the City of San Luis Obispo Local Planning Team reviewed all the mitigation
actions from the 2014 LHMP. The review indicated the City has completed one mitigation action since 2014 and
made continued progress in implementing mitigation projects and building the community’s resilience to
disasters. Of the 29 mitigation actions identified in the 2014 LHMP, the Planning Team has completed the
following action, which the Planning Team notes as being completed in January of 2017:
2.A.12 Add gas pipeline mapping to the City’s GIS resources.
G.5.3 Mitigation Actions
The City of San Luis Obispo Local Planning Team identified and prioritized one new mitigation action based on
the 2019 risk assessment. New and existing actions were prioritized using the process described in Section 7.2.1
of the Base Plan. The new mitigation action identifies implementation strategies, the responsible agency,
potential funding, estimated cost, and implementation schedule.
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City of San Luis Obispo | February 2020 Annex G.36
Table G.21 City of San Luis Obispo’s Mitigation Action Plan
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
SL.1*
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Regularly review and continue to maintain
consistency between the Safety Element,
Municipal Code, zoning regulations, hazard
area maps, and LHMP implementation
strategies. Added 10/2016: Review the
implementation and impacts of SB1069 Land
use zoning
Community
Development
Public Works
Fire
Little to
no cost
Staff Time/
Dept.
Budget
Medium 1-3 years
In progress. Safety
Element to be updated
in 2021
SL.2
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Train all City employees including fire
fighters, police officers, building inspectors,
and public works and utilities staff to levels
appropriate for their hazard mitigation tasks
and responsibilities.
Fire Little to
no cost
Staff Time/
Dept.
Budget
Medium 1-3 years
In progress. Currently
updating a City-wide
training matrix to
ensure employees have
the valid training based
on their position. Once
the matrix is complete
the City will hold
training to ensure all
City employees receive
appropriate training and
certifications. Utilize
new Human Capital
Management software
to ensure new
employees receive
training during
onboarding.
SL.3
Adverse
Weather,
Earthquake,
Flood,
Wildfire,
Provide training for City staff who apply its
building regulations and planning standards,
emphasizing the lessons learned in locations
that have experienced disasters
Fire /
Community
Development
Public Works
Little to
no cost
Staff Time/
Dept.
Budget
Medium 1 yr.
In progress. Additional
modeling has been
completed. The results
of this modeling
indicated that a more
expansive model should
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City of San Luis Obispo | February 2020 Annex G.37
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
Hazardous
Materials
be created which is
underway.
SL.4
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Conduct disaster-preparedness exercises for
the types of hazards discussed in this LHMP. Fire Little to
no cost
Staff Time/
Dept.
Budget
Medium 1 yr.
In progress. Latest
Public Point of
Distribution drill held at
the City of San Luis
Obispo was on
10/ 18/2017. October
2018 Distribution took
place on 10/21/ 18 in
Arroyo Grande and
Atascadero (the two
locations exercised were
intended to cover the
whole county, including
SLO). City plans to
continue participating in
exercises as allowed.
SL.5
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Establish ongoing Disaster Service Worker
training program to include training for City
staff to deal with emergencies as well as
contribute to risk reduction measures.
Fire Little to
no cost
Staff Time/
Dept.
Budget
Medium 1 yr. In progress
SL.6
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Review funding opportunities and establish
centralized internal procedures to coordinate
efforts for securing funds that support risk
reduction measures.
Admin. -
Finance
Little to
no cost
General
Funds/
FEMA HMA
High 1 yr.
In progress. Spring of
2019. The City released
an RFP to hire a grant
writing firm to seek
funding opportunities
to leverage community
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City of San Luis Obispo | February 2020 Annex G.38
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
Hazardous
Materials
improvement. This
includes risk reduction
measures.
SL.7
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Identify hazard mitigation projects eligible for
grants as part of the Capital Improvement
Program planning process.
Public Works/
Utilities
Little to
no cost
Cal OES
FEMA: Up
to $2
Million at
WRRF
Medium 3-5 years
In progress. The Mid-
Higuera Bypass project
is currently being
designed. Once design
is complete, grant
application work will
begin. Utilities (new) - A
2 million grant
application has been
submitted with CalOES
for flood proofing
mission critical facilities
related the Water
Resource Recovery
Facility.
SL.8
Adverse
Weather,
Earthquake,
Flood,
Hazardous
Materials
Assess structural capacity of key assets
including bridges) and pursue infrastructure
improvements as necessary.
Public Works/
Community
Development
Less than
10,000
General
Fund Medium 3-5 years
In progress. As part of
2019-21 financial plan
process the City has
reviewed and prioritized
assets maintenance and
replacement. This
prioritized asset list will
be presented to the City
Council for funding
consideration.
SL.9
Adverse
Weather,
Biological,
Earthquake,
Flood,
Establish a funded program or mechanism to
distribute public information regarding risk
reduction activities and projects at City-
sponsored events. Identify materials available
for use at public education workshops.
Fire Little to
no cost
General
Fund Medium 1-2 years
In progress. Fire
Prevention Open House
occurred on and
10/14/17 and 10/13/18.
Presentations at Cal
Page 436 of 669
Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.39
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
Wildfire,
Hazardous
Materials
Coordinate messaging with external agencies
such as the American Red Cross and
Volunteer Organizations Active in Disasters.
Poly orientations for
students and their
parents. Department is
developing new disaster
preparedness
neighborhood
presentation program
and employee disaster
worker preparedness
beginning FY2020.
SL.10
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Support the efforts and education of people
with access and functional needs to prepare
for disasters.
Fire Little to
no cost
Staff Time/
Dept.
Budget
Medium 1 yr. In progress
SL.11
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Educate the community on individual
preparedness and response to deal with
emergencies at times when professional
responders would be overwhelmed.
Fire Little to
no cost
General
Fund Medium 1-2 years In progress. See SL.9
comments
SL.12
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Offer seminars and/or resources to assist
local / small businesses in planning for
continuity of operations and emergency
preparedness.
Fire Little to
no cost
General
Fund Medium 1-2 years
In progress. Fire
department staff attend
the weekly meetings at
the Downtown
Association and has
updated a fire safety
checklist for festival
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.40
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
Hazardous
Materials
vendors in the
downtown, provided
education to DTA staff.
SL.13*
Adverse
Weather,
Biological,
Earthquake,
Flood,
Wildfire,
Hazardous
Materials
Continue to enforce local codes, ordinances,
and standards pertaining to safe
development and resiliency to natural and
human-caused hazards.
Community
Development
Fire
Little to
no cost
General
Funds/
FEMA HMA
High 1-2 years
In progress. As of April
of 2019, permits have
been issued on all URM
structures. All have been
finalized/closed out
except for four
properties, one of which
is currently being
retrofitted and
remodeled (SLO Brew at
736 Higuera). Permits
have been issued on
two others (1029 and
1035 Chorro) but have
not been
finalized/closed out in
permitting
system. Current status
on these is currently
being researched.
Records indicate the last
of the four has
completed Level A
strengthening, but still
has an outstanding
permit - permit records
and status is currently
being researched.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.41
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
SL.14 Earthquake
Develop and provide managers of mobile
home parks with information on how to
improve the seismic performance of mobile
homes and awareness of flood risk.
Community
Development
Less than
10,000
Staff Time/
Dept.
Budget
Medium 2-3 yrs.
In progress.
Still in planning process;
will be incorporated into
Safety Element)
SL.15
Earthquake,
Wildfire,
Adverse
Weather
The Secure and Resilient Electricity action
would plan for energy independence and
security at critical facilities throughout the
City. By providing grid independent onsite
renewable energy, storage, and energy
management systems, and by providing a
planning and financing framework for future
investments, the City will be able maintain
uninterrupted operations during times of
electricity or natural gas grid instability.
Fire; police;
public works;
utilities;
administratio
n; parks and
recreation
200k to
500k;
California
Energy
Commissio
n;
Monterey
Bay
Community
Power
High 3-5 yrs.
New
Benefits: A resilient
electricity system (solar
and storage) at critical
facilities ensure ongoing
operations during
significant disaster
events and ensures
viability of electric
evacuation vehicles, City
fleet, and transit
vehicles.
SL.16 Earthquake
Continue to implement the Unreinforced
Masonry Hazard Mitigation Plan and
strengthen buildings identified in Levels A
and B.
Community
Development
Fire
10,000
to
50,000
General
Funds/FEM
A HMA
Medium 2-3 yrs. In progress. See SL.13
comments
SL.17 Flood Develop and carry out environmentally
sensitive flood reduction programs.
Administratio
n - Natural
Resources
10,000
to
50,000
FEMA HMA Medium 2-3 yrs.
In progress. The City
continues to assess high
priority erosion and
sedimentation sites
identified in the
Waterway Management
Plan and provide
maintenance or
restoration as
appropriate; review City
owned property and
property with drainage
easements covering
Page 439 of 669
Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.42
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
private properties and
conduct vegetation
management/removal
as needed; and,
complete silt removal
projects at key drainage
locations on a rotating
basis. Assess and
remove as necessary
undesirable trees from
creek system with
tree/landscape
contractors. Natural
Resources Program staff
manages vegetation
trimming or removal to
maintain the riparian
corridors. The EIR for
the Mid-Higuera Bypass
project was adopted
and the 95% plans are
nearing completion.
SL.18 Haz Mat
Continue requiring businesses that use, store,
or transport hazardous materials to ensure
that adequate measures are taken to protect
public health and safety.
Fire Little to
no cost
Certified
Unified
Program
Agency
CUPA)
High
Annual
impleme
ntation
Fire Department CUPA
Participating Agency
completes 100% of
permitted facility
inspections annually to
assure compliance with
the fire code and state
regulations. The fire
department is subject to
audit by the County
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.43
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
CUPA and has passed
all recent audits.
SL.19 Haz Mat
Coordinate with allied agencies to prepare for
hazardous materials incidents. Reference City
EOP and Training and Exercise Plan; Maintain
participation in County hazardous materials
team
Fire Less than
10,000
Certified
Unified
Program
Agency
CUPA)
Medium 1 yr.
In progress. City
Emergency Operations
Plan is currently set to
be updated. City issued
RFP to hire consultant
to update plan in Spring
of 2019 and is expected
to have a completed
plan with associated
training in Winter of
2020.
SL.20 Haz Mat
Maintain City’s web site and other outlets
with information regarding the safe handling
and disposal of household chemicals.
Fire Little to
no cost
Staff
Time/Dept.
Budget
Medium 1 yr. In progress/ongoing
SL.21 Wildfire
Enhance partnerships with CalFire and the
local Fire Safe Council for fuel reduction
efforts.
Fire Little to
no cost
Cal Fire /
FireSafe
Grants
Medium 1 yr.
In progress. As of March
of 2019, The City of San
Luis Obispo is now a
recognized focus group
and voting board
member on the Fire
Safe Council
SL.22 Wildfire,
Drought
Support ongoing urban forest maintenance
and tree trimming programs, to include
planting drought-resistant trees and plants.
Public Works
Urban
Forestry / Fire
Parks &
Recreation /
Natural
Resources
Less than
10,000
General
Fund Medium 1-2 yrs.
In progress. Urban
Forest Services
continues regular
maintenance which
includes pruning and
dead tree removal in
City Streets, Parks and
other City owned
properties.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.44
ID Hazard(s)
Mitigated Description/Background/Benefits Lead Agency
and Partners
Cost
Estimate
Potential
Funding Priority Timeline Status/
Implementation Notes
SL.23 Wildfire
Continue to conduct current fuel
management programs and investigate and
apply new and emerging fuel management
techniques.
Fire/Natural
Resources
Director/Parks
and
Recreation
10,000
to
50,000
FEMA and
Fire Safe
Council
grants
High 1 yr.
In progress. The Natural
Resource Manager has
taken lead on all fuel
management funds and
projects in the City
Open Space. Additional
grant funding has been
obtained to augment
allocated fuel
management budget.
SL.24 Wildfire Require an enhanced fire protection plan in
Local Very High Fire Severity Zones. Fire Less than
10,000
Staff
Time/Dept.
Budget
Medium 1 yr. In progress.
SL.25 Biological Continue offering free flu vaccines to City
employees.
Human
Resources
Less than
10,000
County
Program Medium
Annual
impleme
ntation
In progress. Continued
participation in the
County Public Health
Point of Distribution
program.
SL.26 Biological
Educate and encourage City employees to
maintain a healthy work environment by
utilizing sick and other leave benefits to avoid
coming to work when sick or contagious and
encouraging employees to develop plans for
caring for sick family members taking care of
ill family members.
Human
Resources
Little to
no cost
General
Fund Medium
Annual
impleme
ntation
In progress. Include in
ongoing wellness,
benefits, and leave of
absence training,
education, and general
communications.
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.45
G.6 Implementation and Maintenance
Moving forward, the City will use the mitigation action table in the previous section to track progress on
implementation of each project. As illustrated in the completed actions table (Table G.21) much progress has
been made since the plan was originally developed. Implementation of the plan overall is discussed in Chapter 8
in the Base Plan.
G.6.1 Incorporation into Existing Planning Mechanisms
The information contained within this plan, including results from the Vulnerability Assessment and the
Mitigation Strategy, will be used by the City to help inform updates and the development of local plans,
programs and policies. The Engineering Division may utilize the hazard information when implementing the
City’s Community Investment Program and the Planning and Building Divisions may utilize the hazard
information when reviewing a site plan or other type of development applications. The City will also incorporate
this LHMP into the Safety Element of their General Plan, as recommended by Assembly Bill (AB) 2140. This
enables the City of San Luis Obispo to qualify for additional funding through the California Disaster Assistance
Act should the State determine there to be a need and/or additional funding to be available.
California State Assembly Bill 162 requires the General Plan Land Use Element to identify existing and proposed
uses and flood mitigation strategies within the 100 -year floodplain. The HMP should be referenced and used to
inform the Land Use Element in order to meet this requirement. California State Senate Bill 1241 requires the
Safety Element to incorporate wildfire hazard considerations for State Responsibility Areas (SRAs) and lands
within very high fire severity zones. These areas are already depicted within the Safety Element and this Annex.
They will be reviewed and updated as appropriate during the future updates to both of these documents.
Whenever there are substantive changes to the County HMP or this Annex, those involved in other relevant
planning mechanisms in the City will be included in the review process.
As stated in Chapter 8 of the Base Plan, the HMPC representatives from the City of San Luis Obispo will report
on efforts to integrate the hazard mitigation plan into local plans, programs and policies and will report on these
efforts at the annual HMPC plan review meeting.
G.6.2 Monitoring, Evaluation and Updating the Plan
The City will follow the procedures to Monitor, review, and update this plan in accordance with San Luis Obispo
County as outlined in Chapter 8 of the Base Plan. The City will continue to involve the public in mitigation, as
described in Section 8.3 of the Base Plan. The Administrative Analyst in the City Fire Department will be
responsible for representing the City in the County HMPC, and for coordination with the City LPT, including
relevant staff and departments during plan updates. The City realizes it is important to review the plan regularly
and update it every five years in accordance with the Disaster Mitigation Act Requir ements as well as other State
of California requirements. In order to ensure that regular review and update of the HMP occurs, the LPT will
convene annually to review and discuss mitigation progress and any new concerns that may benefit from
mitigation activities. During each annual review, the LPT will review each goal and objective to evaluate its:
Relevance to the evolving setting and needs of the City of San Luis Obispo
Consistency with changes in State and Federal policy
Relevance to current and expected conditions
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Annex G: City of San Luis Obispo
San Luis Obispo County Local Hazard Mitigation Plan
City of San Luis Obispo | February 2020 Annex G.46
The LPT will review the Risk Assessment portion of the plan to determine if the information should be updated
or modified. The parties responsible for various implementation should be updated or modified. The parties
responsible for various implantation actions will report on:
Status of their projects
Implementation processes that have worked well
Any difficulties encountered
How coordination efforts are proceeding
Which strategies should be revised
Page 444 of 669
Appendix D Planning and Outreach Process
Outreach and Community Participation
A foundational first step in Resilient SLO’s outreach and engagement strategy was to
create a Community Outreach Plan (Exhibit A) that identified key stakeholders and
population groups; established guiding principles, goals, and triggers; and outlined
strategies and tactics that ensured the project was informed by community needs,
priorities, and interests.
The Community Adaptation and Safety Element (CASE) reflects the community’s vision
for resilience to hazards and future disruptions. Community input shaped its development
and was gathered through virtual community webinars, online surveys, “Stories of
Resilience” submissions, a Resilience Roundtable, and working groups.
The Resilience Roundtable was an ad-hoc community advisory group of local experts
that provided input on the City’s approach to adapting to climate change. Community
members were selected to serve on the Roundtable based on their traditional or non-
traditional expertise in climate change resilience topics. The 1 4 Roundtable members
represented a diversity of backgrounds and areas of expertise. The Roundtable met five
times throughout the development of the CASE and provided critical input on key project
deliverables to date.
The working groups were open to the public and led by Resilience Roundtable Members
and project leads. Working groups provided additional community feedback on how
climate change impacts to community resilience, the built environment, environmental
justice, and the natural environment should be addressed.
Three community webinars were held to inform community members about the project,
increase community knowledge of climate change adaptation and resilience topics, and
gather feedback. Two separate surveys were also shared to gather community priorities,
concerns, and feedback on actionable strategies for the city. Finally, community members
were invited to share their experiences and lessons learned in overcoming disaste rs.
These “Stories of Resilience” provide community perspectives on local resilience to
historic disasters. Because of COVID-19 precautions, all community engagement
occurred virtually.
• Online Survey – August through September 2020
• Stories of Resilience Submissions – December 2020 through December 2021
• Resilience Roundtable Meeting #1 – January 15, 2021
• Community Webinar – January 28, 2021
• Online Survey – February through March 2021
• Built Environment Working Group Meeting – March 2, 2021
• Natural Systems Working Group Meeting – March 4, 2021
Page 445 of 669
• Community Resilience Working Group Meeting – March 4, 2021
• Resilience Roundtable Meeting #2 – March 11, 2021
• Community Webinar – May 13, 2021
• Community Resilience Working Group Meeting – July 12, 2021
• Natural Systems Working Group Meeting – July 13, 2021
• Built Environment Working Group Meeting – March 14, 2021
• Environmental Justice Working Group Meeting – July 19, 2021
• Community Strategy Workshop – July 22, 2021
• Resilience Roundtable Meeting #3 – August 13, 2021
• Community Education Event – January 24, 2021
• Resilient Roundtable Meeting #4 May 10, 2022
• Climate Party – August 13, 2022
• Resilient Roundtable Meeting #5 October 11, 2022
Stories of a Resilient SLO (community webinar) – January 28, 2021: This event
introduced the Resilient SLO project and presented findings from the project’s Baseline
Conditions Report. Speakers included Mayor Heidi Harmon; Chris Read, City
Sustainability Manager; Adrienne Greve, Cal Poly Professor; Beya Makekau, Director of
Student Diversity and Belonging, Cal Poly; John Lindsey, Marine Meteorologist for PG&E;
and Kai Lord-Farmer, Consultant at Ascent Environmental.
Re-energizing SLO – Building an Energy Resilient Future (community webinar) – May 13,
2021: This community education webinar explored energy resilience and its connection
with public safety, economic resilience, and disaster preparedness. Featured speakers
included Tanya Barham, CEO and Founder of Community Energy Labs; Craig Lewis,
Executive Director of the Clean Coalition; and Kajsa Hendrickson, representing the Solar
on Multi-Family Affordable Housing Program.
Adapting to a Changing Climate Workshop – Strategies for a Resilient SLO (virtual
community workshop) – July 22nd, 2021: This community workshop centered around a
community discussion of adaptation strategies to address climate change impacts. The
event also featured a short presentation of anticipated climatic changes by project
consultant Kai Lord-Farmer from Ascent Environmental.
City Staff and Partner Agency Engagement
City staff from key departments provided input on the project through the City’s Green
Team, an interdepartmental collaborative body of city staff. The Green Team focused on
capacity building for the purposes of climate adaptation for three Green Team meetings
which met on an ongoing basis to work on sustainability programs . Additionally, specific
departments and outside agencies were consulted throughout the development of the
CASE to support the development of the goals, policies, and programs that affect their
areas of expertise and responsibility. Key departments and partner agencies consulted
include:
• Community Development Department
Page 446 of 669
• Office of Sustainability
• Public Works Department
• Fire Department
• Police Department
• Utilities Department
• Caltrans District 5
• San Luis Obispo County
Surveys
Six surveys were shared to gather community priorities, concerns, and feedback on
actionable strategies for the city. In addition to more traditional surveys, community
members were invited to submit “Stories of Resilience” to share their experiences and
lessons learned in overcoming disasters. These “Stories of Resilience” provide
community perspectives on local resilience to historic disasters.
Community Priorities Survey – August 2020 – September 2020: This survey sought to
gather broad input on overall community priorities, concerns related to climate change
impacts, experience with past hazards and response efforts, and priorities for local action.
Survey results informed the development of the Vulnerability Assessment and community
outreach activities throughout the project. The survey, consisting of 19 questions, and had
328 responses. The survey results were used to inform the development of goals, policies
and programs (Exhibit B).
Stories of Resilience Submissions – December 2020 – Present: Community members
were invited to submit stories about how they had overcome past challenges. Stories
were shared on the project website and used to understand and celebrate how ou r
community has demonstrated resilience. The Stories of Resilience are available on the
City’s website Resilient SLO (https://www.slocity.org/government/department-
directory/city-administration/office-of-sustainability-and-natural-resources/resilient-slo-
2246).
Climate Strategies Survey – February 2021 – March 2021: This survey invited the
community to share ideas for strategies to increase the city’s long -term resilience to
climate change impacts (Exhibit C)
Climate Change Impacts on Community Organizations Survey – June 2021: This survey
asked community organizations how their operations were being affected by climate
hazards and how they were preparing for the impacts of climate change. The results of
the survey helped inform the project Vulnerability Assessment (Exhibit D).
Community Asset Mapping Survey – August 2021: This survey allowed the public to map
community strengths that support social cohesion, wellbeing, and disaster resilience. The
data gathered can help the city understand existing assets, what should be strengthened
and invested in, and what resources are missing (Exhibit E).
Page 447 of 669
Environmental Justice Survey for Community Organizations – August 2021: The
Environmental Justice Survey for Community Organizations was intended to gather input
on environmental topics from organizations that serve vulnerable and/or disadvantaged
communities in the City of San Luis Obispo. The survey findings were used to inform the
integration of environmental justice into the CASE (Exhibit F).
Page 448 of 669
1
Resilient SLO Community Engagement Plan
The primary objective of Resilient SLO is to update the City of San Luis Obispo’s Safety Element of
their General Plan, which will guide policies, programs, and investments for future development. The
Safety Element will be updated to consider current and future climate change risks and hazards, as
well as strategies to mitigate, adapt, and build resilience to the worsening impacts of climate change.
As a long-range planning document and the necessity for all stakeholders to be involved in building
climate resilience, inclusive community engagement is critical to the overall success of this project.
This Community Engagement Plan outlines key stakeholders and population groups, guiding
principles, goals and triggers, and strategies and tactics to ensure that the project is informed by
community needs, priorities, and interests while educating community members about climate risks
and adaptation strategies. Community participation will be incorporated into all stages of the
adaptation planning process and input will directly impact the direction and prioritization of project
outcomes.
Community engagement will fulfill three key purposes:
1. Inform: To provide the public with balanced and objective information to assist them in
understanding the problem, alternatives, opportunities and/or solutions. Community
members will receive critical information on current and future climate risks, hazards, and
vulnerabilities, as well as best practices for building individual and community resilience.
2. Consult: To gather input and obtain feedback on the direction of the project, adaptation
options and alternatives, and adaptation strategies to include in the City’s updated Safety
Element. Community members will be consulted through a variety of means to gain insight
into their perspective on adaptation strategies and priorities.
3. Collaborate: To partner with the public in each aspect of the decision, including the
development of alternatives and the identification of the preferred solution. Community
members will engage in dialogue and discussion with project partners and local stakeholders
to evaluate best practices and inform the updated Safety Element.
It should be noted that the timeline for community engagement activities will incorporate a diversity
of approaches and that opportunities for the community to collaborate (and directly contribute to the
community resiliency vision) will be a key priority.
Stakeholders
Understanding who key stakeholders are in the city of San Luis Obispo will help to ensure
community engagement activities are designed and implemented with the intended audience in
mind. It will also help to determine if public input gathered is representative of the city’s population
and inform targeted outreach that may be needed to engage underrepresented and marginalized
populations.
Page 449 of 669
2
Community Profile
The City of San Luis Obispo has 46,548 inhabitants living on 13.2 square miles. Their three largest
private employers are: PG&E, Tenet Healthcare, and Compass Health, Inc. Details on housing and
household income are noted on their website:
According to Census Data, the majority of the population (~71%) is between the ages of 18 and 64.
12.5% of the population is 65 or older. 17% of the population speak a language other than English at
home and 18.3% of the population is Hispanic or Latino. 94.4% of the households have a computer;
90.1% have a broadband internet connection. Land Use details can be found here. Zoning details
can be found here.
CalEnviroScreen Results
EnviroScreen Results for City of San Luis Obispo
When engaging stakeholders, the project team will prioritize residents and neighborhood leaders in
geographic areas most vulnerable to climate change based on initial findings from the vulnerability
assessment. Results from CalEnviroScreen (CES) will also inform priority communities to engage
based on those who face the most significant environmental hazards. CES scores for the census
tracts within the city’s boundaries range from 6.69 to 26.9. The hardest hit census tract -
Page 450 of 669
3
6079011103 with a score of 26.9 - has a CES percentile of 53.69%. This means that it scores below
46.3% of all census tracts within the State. The city does not have any disadvantaged communities
as designated by SB-535. It should also be noted that census tracts do not align with city
boundaries, so isolating the target neighborhoods within the tract may pose a challenge.
CES Percentiles & Scores by SLO Census Tracts
San Luis Obispo also serves as an economic hub for the region. A wildfire or natural disaster could
disrupt transportation routes and prevent commuters from traveling into the city. As such, commuters
should also be seen as key stakeholders, in addition to residents. The initial community engagement
survey conducted for Resilient SLO allowed both residents and non-residents who work in the city to
provide input.
Potential Partners
In order to successfully reach stakeholders, particularly underrepresented and marginalized
populations, the project team will identify, engage, and partner with trusted local organizations.
Promotional partners will be recruited for each engagement activity to help amplify the project team’s
outreach efforts. The project team intends to strengthen relationships with promotional partners
throughout the course of the project to ideally sustain ongoing engagement in the City’s climate
adaptation initiatives and future community engagement efforts. Co-sponsors may also be able to
support the procurement of additional materials to maximize participation.
The project team compiled a list of potential partners to engage, which includes:
Page 451 of 669
4
● Local and regional nonprofit organizations including those focused on environmental issues,
as well as housing, food, economic development, transportation, agriculture, civic
engagement, arts and culture, and other social services
● Neighborhood associations
● Cultural centers
● Professional associations
● Business associations
● Media outlets
● Schools, colleges, and universities
● Organizations serving SLO’s Latinx communities
This list also includes partners that can be engaged through different platforms, such as Twitter,
Facebook, and Instagram. The project team will continue building this list throughout the course of
the project.
Guiding Principles
All community outreach and engagement activities will be designed and implemented in a manner
that upholds the following guiding principles, which are described in further detail in Participation
Tools for Community Planning.
PRINCIPLE DEFINITION ACTION ITEM
Inclusiveness
Events are inclusive to all members of
the community and include strategies
to engage marginalized populations.
The unique needs of community
populations will be considered in
developing engagement strategies
and the project will provide a diversity
of opportunities to participate.
Respect
Community members are
acknowledged for their unique
perspectives and knowledge of local
community issues
Community members are thanked for
their contributions after every
engagement activity.
Relevance
Issue areas align with community
values and shared needs and
aspirations
Partners will incorporate community
values and needs into any community
outreach or engagement activities.
Clear Purpose
and Scope
A roadmap of the project is available
from the beginning and all participants
have a clear understanding of how
their input will be utilized and what
future deliverables they can expect to
see.
Details of Resilient SLO are publicly
available and contact information is
provided for any individual with
questions about the project.
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5
Knowledge
Community members have access to
the necessary tools and technical
information to share useful insights.
Community members are provided
with sufficient background information
and resources to fully participate in
the engagement activity.
Trust
Community members can trust project
leads and community partners to utilize
feedback and incorporate into project
deliverables.
Community members are provided
with the details on how their
comments will be translated into
project deliverables.
Sustained
Engagement
Relationship-building with the
community continues beyond the
project timeline and provides an
ongoing means to support concerns
and aspirations
Project partners will provide an open
line of communication for project
participants and detail pathways to
address ongoing issues.
Results
Community members are provided with
public evidence that their input has
been valued and incorporated into
project outcomes.
When deliverables are drafted or
finalized from engagement activities,
respondents will receive a follow-up
email outlining what has been
accomplished.
Additionally, the project team will consider the following key questions when conducting community
outreach and engagement, which are further described in the City’s Public Engagement and Noticing
Manual).
1. What is the action/program/project you need to communicate?
2. Who makes the final decision on the item, is this a staff decision? Subject to advisory body
review? Will City Council ultimately receive the item for action?
3. What type of community interaction is desired?
4. Who needs to/wants to be informed?
5. When does the outreach need to happen?
6. What needs to be done?
7. What does success look like?
Cultural Considerations
It is also important to consider cultural factors when conducting community engagement activities to
ensure that all communities are given equal access to opportunities to participate and that
participants feel inspired to participate due to their unique contributions.
The Greenlining Institute’s Making Equity Real: Community Benefits & Engagement Guide details
key cultural considerations to prioritize when conducting community engagement, which will serve as
guiding principles for the project team.
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CULTURAL
FACTORS
HOW TO ADDRESS CULTURAL CONSIDERATION FACTORS IN COMMUNITY
ENGAGEMENT
Literacy Level
It may be more difficult to reach out to Limited English Proficient (LEP)
individuals, immigrant communities, or people with lower educational
attainment. Project leads should design materials and events for community
engagement to accommodate different literacy levels and provide background
information when referring to complex concepts. Avoid the use of acronyms
where possible.
Socioeconomic
Status
Groups with lower socioeconomic status are often disproportionately affected
by environmental hazards while facing greater barriers to participation in
engagement efforts to remediate them. These barriers may be addressed
when considering factors such as the location and timing of activities,
accessibility by public transportation, availability of childcare, and availability of
food.
Language
All communication should be done in the major languages spoken in the
community. This includes written background materials, live interpretation at
key public events and captioned videos. Interpreters should be available at
meetings when it is clear that non-English speaking members of the community
will be present.
Local History
Certain communities may have participated in previous engagement efforts
that did result in change. Over time, either not being included or participating
and/or not feeling utilized may affect future participation.
Understanding the local context is helpful prior to beginning engagement.
Engaging with local CBOs that understand local history may help advance
community participation in engagement activities. We strongly recommend
ongoing information sharing to insure transparency, help maintain community
relationships and build trust in the process.
Competing
Interests and
Limited Time
Community members may have many competing interests and limited time.
Allowing different levels and types of involvements in the process can help
foster participation.
● Going to places where people already gather to allow community
members to give input without a large time commitment at a time that is
convenient for them.
● Other more time-intensive activities, such as focus groups, charrettes,
and workshops, can be made available for stakeholders who are
interested in providing more in-depth input.
Goals and Triggers
Effective adaptation requires broad engagement. As such, participant demographics will be captured
for each engagement activity and the project team will work to ensure representation from key
demographic groups within the city. The following minimum response targets, informed by 2018
Census and American Community Survey results, will serve as response and participation goals. If
these goals are not met, the project team will conduct targeted outreach efforts and engage with
appropriate partners to engage underrepresented segments of the city’s population. The timeline for
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targeted outreach, specifically when addressing the digital divide, may also need to be reviewed
more in-depth to ensure that there is sufficient time for such populations to participate.
DEMOGRAPHIC ACCEPTABLE RANGE
(PERCENT)
MINIMUM RESPONSE
10% 15% 20%
Housing Situation
Homeowner 63% - 73% (68%) 2971 4457 5942
Renter 27% - 37% (35%) 1273 1910 2547
Age
Under 18 8.1% - 18.1% (13.1%) 382 573 764
18 - 24 29.9% - 39.9% (34.9%) 1410 2115 2820
25 - 34 8.6% - 18.6% (13.6%) 406 608 811
35 - 44 3.3% - 13.3% (8.3%) 156 233 311
45 - 54 3.7% - 13.7% (8.7%) 174 262 349
55 - 64 3.9% - 13.9% (8.9%) 184 276 368
Above 65 7.5% - 17.5% (12.5%) 354 531 708
Ethnicity
American Indian or
Alaskan Native .3% 14 21 26
Asian .6% - 10.6% (5.6%) 28 42 57
Black or African American 2.0% 94 141 189
Hispanic, Latino or
Spanish origin 13.3% - 23.3% (18.3%) 627 941 1254
Native Hawaiian or Pacific
Islander .1% 5 7 9
White or Caucasian 65.7% - 75.7% (70.7%) 3098 4648 6197
Other .2% 9 14 19
Household Income
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Less than $10,000 6.6% - 16.6% (11.6%) 311 467 632
$10,000 - $14,999 2.3% - 12.3% (7.3%) 108 163 217
$15,000 - $24,999 6.2% - 16.2% (11.2%) 292 439 585
$25,000 - $34,999 1.3% - 11.3% (6.3%) 61 92 123
$35,000 - $49,999 6.2% - 16.2% (11.2%) 292 439 585
$50,000 - $74,999 10.2% - 20.2% (15.2%) 481 722 962
$75,000 - $99,999 5.8% - 15.8% (10.8%) 274 410 547
$100,000 - $149,999 7.8% -17.8% (12.8%) 368 552 736
$150,000 - $199,999 .8% - 10.8% (5.8%) 38 57 75
$200,000 or more 2.8% - 12.8% (7.8%) 132 198 264
Strategies and Tactics
Due to public health concerns and public gathering restrictions due to COVID-19, community
engagement events for Resilient SLO will be virtual. This does not preclude eventual in-person
engagement at a later date; however this plan focuses on virtual activities.
Virtual engagement activities present unique opportunities and challenges. As a consequence of
COVID-19, many individuals are working remotely and can more easily incorporate virtual
engagement activities into their schedule. Community members are also likely to be more familiar
with online platforms and tools. Virtual engagement can also attract individuals who would otherwise
not attend an in-person event due to space constraints, transportation challenges, or child care
needs.
At the same time, virtual activities can pose a technical barrier for certain community groups as
participation can be hindered by a slow internet connection and/or limited knowledge about how to
use the tools provided. Virtual engagement can also be impersonal and participants may not receive
the full benefits of in-person events, particularly networking and relationship-building. The project
team will identify and employ strategies to address challenges resulting from virtual engagement
activities.
Outreach Strategy
To reach a broad audience, the project team will employ a variety of tactics to promote community
engagement and education activities, including:
● Postcards to residents,
● E-notification,
● Website posting,
● Social Media,
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● Utilities billing insert,
● Community Calendar,
● Signage,
● Paid media (newspaper, radio, outdoor/transit),
● Press Release,
● Neighborhood meetings, and
● Mailed Announcement.
Types of Activities
The following virtual engagement activities are divided based on their capability to inform, consult, or
collaborate with the general public. All types of engagement activities will need to be considered in
order to ensure this process is as equitable and accessible as possible.
INFORM
ACTIVITY PURPOSE CONSIDERATIONS
Website Hub
A central website where residents and
stakeholders can visit to see updates from the
project, view upcoming events, and provide
input through a comment form or survey. The
project’s website has been created:
https://www.lgc.org/resilient-slo
Ensure that the website is
easy to navigate and is ADA-
compliant.
Resource
Library
Articles, podcasts, and other media linked as a
resource to help residents learn more about
climate change risks and adaptation
strategies.
Example: City of Culver City
General Plan Planning
Library
Informational
Webinar
A webinar can be organized to share
information with a public audience. Including a
Q&A opportunity can help to create a more
engaging experience. Webinars can be easily
recorded and added to the project website.
Webinars can also be used to organize
speaker series.
Provide participant guidance
to help address potential
technical issues in advance
Social Media
Campaign
A coordinated social media campaign that
includes local partners can help to inform the
public of climate risks, hazards, vulnerabilities,
adaptation solutions, and resources available
in an engaging format that can help to build
momentum. The campaign can be conducted
through multiple platforms such as Facebook,
Twitter, Instagram, LinkedIn, and more.
Early engagement with local
partners
CONSULT
ACTIVITY PURPOSE CONSIDERATIONS
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10
Online Survey
Surveys will be helpful to gather input from a
broad audience, especially over time. Surveys
can also be more accessible compared to
scheduled events, but should be balanced
with other activities that are more engaging.
● Keep survey brief
● City uses OpenGov for
public surveys
Mapping Survey
In addition to traditional surveys, different tools
can be used to gather input on specific
geographic locations within the city.
Tool:
https://maptionnaire.com/
Mailed or
Telephone
Survey
Mailed or telephone surveys can be used to
help address the digital divide.
Video-guided
Questionnaire
A set of short videos can be created to provide
additional context for public members to
complete targeted questionnaires. Residents
can watch the videos at their own pace and
then respond to a survey to give their thoughts
and suggestions on each one.
● Example: City of
Sacramento 2040-
General Plan Workshop
App-based
Engagement
Different app-based engagement tools can be
used to solicit comments, ideas, and
suggestions from community members that
can then be upvoted by other participants.
● Tool: MindMixer.com
● Example: Inspire Boulder
Interactive
Webinar
Webinars can also be designed to be more
interactive by utilizing polling and breakout
room features.
If breakout rooms are used,
need to identify a sufficient
number of facilitators
COLLABORATE
ACTIVITY PURPOSE CONSIDERATIONS
Virtual
Roundtable
Discussions
Small group discussions can be organized to
engage key stakeholders in a dialogue to
gather input and/or reach consensus.
● Aim for max of x
participants
● Tools: Zoom
● PollEverywhere can be
used to create more
interactive polling than the
options already in Zoom
Virtual Public
Workshop
A series of live webinars where project leads
can give updates on the findings of:
● Current and Future Hazards
Assessment
● Vulnerability Assessment
● Hazards and Vulnerability Report
● Tools: Zoom, GoogleMeet
● Considerations:
Advertising the event to
broad audiences
● Digital Divide
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Community members can ask questions and
give feedback in real time.
IN-PERSON ACTIVITIES
If in-person activities are able to be conducted during the project term, different tactics will be
employed, such as the following. In such an event, this plan will be updated to expand on in-person
activities, opportunities, and best practices.
● Utilizing a train-the-trainer approach to equip community leaders and community-based
organizations with the tools and resources to educate and/or engage their constituents.
● Organizing community design charrettes to engage community members in location-specific
planning exercises.
● Organizing workshops and pop-up events to engage and educate the public.
● Leveraging existing meetings, such as neighborhood association meetings.
● Community bike parties, trivia nights, and other opportunities to reach the public in engaging
and interactive ways.
Community Engagement Roadmap
Each component of the community engagement process will have its own roadmap. Staging the
planning process will allow the project team to remain responsive and adaptive. Each roadmap will
contain most, if not all, of the following categories:
● Purpose
● Timeline
● Guiding Principles
● Promotional Language
● Promotional Partners
● Addressing the Digital Divide
● Goals and Triggers
A draft list of community engagement and education activities is listed below.
ACTIVITY PURPOSE & FORMAT TIMING
A
Community Priorities Survey
To gather broad input on overall community priorities,
concerns related to climate change impacts, experience
with past hazards and response efforts, and priorities for
regional action. Results will inform the vulnerability
assessment and future community engagement and
education activities.
Completed in October
2020
B
Climate Risks and Vulnerabilities Webinar
To increase public understanding of current and future
climate change risks, hazards, and vulnerabilities. Video
recordings will be produced to serve as ongoing
educational resources.
January 2021
C Vulnerability Assessment Input Platform January - February 2021
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To solicit community input and feedback on the draft
vulnerability assessment to identify and address gaps and
inconsistencies. An online platform will be created, which
may include video-guided and/or map-based
questionnaires.
D
Adaptation Strategies Input Platform
To gather stories of resilience and ideas for adaptation
strategies from San Luis Obispo stakeholders. An online
platform will be used to allow community members to
provide input over an extended period.
January - February 2021
E
Vulnerability Assessment Webinar
To present the finalized vulnerability assessment as an
educational opportunity for community members and
stakeholders. Breakout discussions may be organized to
further engage participants.
April - May 2021
F
Adaptation Strategies Prioritization Platform
To consult the public on the prioritization of adaptation
strategy options, which will also include strategies
identified through Activity D. An online platform will be
used to allow community members to provide input over
an extended period.
June - July 2021
G
Draft Safety Element Presentation
To provide the public with the opportunity to review and
provide feedback on the draft Safety Element prior to
finalization. Breakout discussions may be organized to
further engage participants.
October 2021
H
Community Capacity Building Discussions
To engage community members in adaptation solutions by
providing trainings, connections, and guidance to increase
and sustain their engagement. These may be organized in
partnership with local organizations and segmented by
population group to provide more targeted guidance.
January 2022
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1 RESILIENT SLO COMMUNITY PRIORITY SURVEY: RESULTS
SUMMARY
1.1 PURPOSE
Resilient SLO, an initiative of the City of San Luis Obispo, will result in an update to the City’s General Plan to include strategies for building community resilience to the impacts of climate change. The project team consists of the Local
Government Commission as the project managers and Ascent Environmental, Inc. as the lead technical consultant. Resilient SLO is designed to be a comprehensive, innovative, and inclusive planning process – one that elevates
community voice in decision-making, utilizes best-available science and practices, and focuses on the real challenges that individuals face in the city of San Luis Obispo: climate change, the ongoing COVID-19 pandemic, and economic uncertainty. The Community Priority Survey is one means of the inclusive planning process. This survey sought to gather broad input on overall community priorities, concerns related to climate change impacts, experience with past hazards and response efforts, and priorities for local action. Results will be utilized in the short-term to inform the
vulnerability assessment and future community engagement and education activities. Long- term outcomes from the larger Resilient SLO project include educational activities to ensure San Luis Obispo residents and businesses are equipped with the information and strategies to prepare and build resilience to climate change risks and hazards, a
comprehensive vulnerability assessment of the city’s physical assets, and infrastructure, an updated Safety Element of the General Plan with identified adaptation strategies across key sectors, an implementation guide that translates
strategies into detailed work plans and model policies to catalyze action, trainings for City staff and supporting organizations to build collective capacity to respond to climate change hazards and disasters, and an Implementation Guide with work plans and model policies to catalyze action.
1.2 METHODOLOGY
This survey was the first opportunity for community members to give feedback on their concerns related to climate impacts, hazards, and vulnerabilities to be addressed in the larger Resilient SLO initiative. To inform the updates to the hazard mitigation plan and Safety Component of the General Plan, the project team was interested in hearing
from community members on their climate impact experiences and their priorities, in order to incorporate effective planning measures. The climate impacts mentioned in the core questions came from impacts identified for the region in California’s 4th Climate Change Assessment. Other priority areas were sourced from current events and stressors, such as COVID-19. The project team began drafting the survey in July 2020. Team leads on the project from the City, the Local Government Commission, and Ascent Environmental, Inc. met bi-weekly on project deliverables.
1.3 QUESTIONS
The survey consisted of 19 questions, including 13 multiple-choice and 6 open-ended. The survey included 4
demographic questions to evaluate whether respondents reflected the diversity of the local community. Respondents were also asked the zip code of both their residence and employment to gauge whether they lived or worked in the City. The remaining questions evaluated community priorities, concerns over climate hazards and impacts,
experiences with hazards, evaluation of the City’s response to past hazards, and interest in further information on resilience and adaptation topics. The survey opened on August 31st, 2020.
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The scale and categories for each core multiple-choice question are noted below:
Question Scale Categories
Which of the following issues are you currently concerned about? Level of Concern:
Not at all
Somewhat
Very
Access to Healthy Food
Affordable Housing
Air Pollution
COVID-19
Earthquakes
Job Security and Economic Vitality
Social Equity and Justice
Transportation affordability and accessibility
Tree health and maintenance
Water Pollution/ Stream health
Which of the following climate change
impacts are you concerned about? Level of Concern:
Not at all
Somewhat
Very
Drought and Decreased Water Supply
Flooding and Storm Damage
Hotter Temperatures and Heat Waves
Sea Level Rise
Wildfires
Wildfire Smoke
How concerned are you that climate change will impact any of the following areas? Level of Concern
Not at all
Somewhat
Very
Access to Beaches and Open Space
Community Culture
Employment and Job Security
Evacuations
Property Value
Public Health and Safety
Transportation Disruptions
Utility Disruptions and Power Outages
Which of these hazards have you been
personally affected by in the past 1-3 years in
the City of San Luis Obispo?
Level of Impact
Not at all
Somewhat
Significantly
Air Pollution
Drought and Water Supply
Erosion
Extreme Rainfall
Flooding
Hotter Temperatures and Heat Waves
Tule Fog
Wildfires
Wildfire Smoke
For each hazard that you were affected by,
please rank your level of satisfaction with the
City's response.
Level of Satisfaction
Not at all
Somewhat
Very
Air Pollution
Drought and Water Supply
Erosion
Extreme Rainfall
Flooding
Hotter Temperatures and Heat Waves
Tule Fog
Wildfires
Wildfire Smoke
How would you prioritize the following
actions in the city of San Luis Obispo?
Rank Order (1-7) Parks
Public transportation
Housing
Trails
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Question Scale Categories
Space for Businesses
Land Preservation
Agricultural Land Preservation
1.4 DEMOGRAPHIC QUESTIONS
The city sought to reach out to respondents that were representative of the diverse population of the City of San Luis
Obispo. Respondents were given the option of providing key demographic details respondents or declining to answer. The questions included in this section are detailed below:
[Age] What is your age?
Under 18
18 - 24
25 - 34
35 - 44
45 - 54
55 - 64
Above 65
Prefer not to say
[Race/Ethnicity] How would you describe yourself? Please select all that apply.
American Indian or Alaska Native
Asian
Black or African American
Hispanic, Latino, or Spanish origin
Middle Eastern or North African
Native Hawaiian or Other Pacific Islander
White or Caucasian
Other (please specify)
Prefer not to say
[Household Income] What was your total household income before taxes in 2019?
Less than $30,000
$30,000- $39,999
$40,000 - $59,999
$60,000 - $79,999
$80,000 - $99,999
$100,000 or more
Prefer not to say
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1.5 OUTREACH
Original plans for survey outreach included in-person events and in-person survey opportunities to complement online and phone surveys. Due to COVID-19 and quarantine restrictions, these forms of outreach could not take
place; outreach had to be fully remote. The primary form included an online survey on the city’s OpenGov web portal which also regularly hosts surveys for other city initiatives outside this project and for regularly scheduled city meetings that are broadcast on the website. In an effort to bridge the digital divide, the project team worked with the
city to establish a phone line for respondents to call in their responses. However, no respondents utilized the phone line to respond. In-person events would have reached more respondents who do not have internet access but the inability to hold in-person events affected the ability to fulfill that form of engagement.
To promote the phone-line and online survey, the project team reached out over e-mail or social media to organizations, businesses and agencies that serve populations who live, work, or go to school in San Luis Obispo.
These promotional partners were asked to share the survey with their audiences and were given a promotional toolkit with sample email language and social media posts. A wide variety of organizations were contacted (approximately 126), in the hopes of reaching the diverse composition of the local community. Organizations contacted included local educational institutions, non-profits, coalitions, professional associations, cultural organizations, and businesses. Most outreach was conducted by email; 115 organizations were contacted via email. Highly trafficked social media accounts were also contacted. 11 organizations and/or individuals were contacted via social media. Promotional partners received a promotional kit, which included sample e-mail language, sample social media posts plus photo
postcards, and a high level overview of key details, to share with their constituents. The survey deadline, originally the end of September, was extended to October 11th to give more time for responses. Once the deadline was extended, organizations were notified of the extension. In addition to outreach through promotional partners, the survey was
also shared on 1-2 times per week on City’s social media accounts.
On September 17th, a Spanish version of the survey was created on Survey Monkey. On September 29th, the entire
promotional kit was translated to Spanish to conduct more outreach to the Spanish speaking community and shared with promotional contacts. Promotional asks to Latino, Hispanic, and Spanish-speaking cultural groups primarily went through Cal Poly students. Despite reaching out to organizations, the Spanish language survey posted on Survey Monkey did not receive any responses.
1.6 PROCESS OF ANALYSIS
1.6.1 Core Questions
Responses for each multiple-choice core question were analyzed to reveal the following:
a. Areas of Highest Concern/Impact/Satisfaction (for all Respondents)
b. Areas of Highest Concern/Impact/Satisfaction (for key Demographic Groups)
In evaluating the areas of highest concern/impact/satisfaction for all Respondents, we included all relevant measures for the specific category (ex. “Not at all”, “Somewhat”, “Very/ Significantly”). Responses are shown as absolute
numbers (total counts) unless otherwise indicated.
In evaluating the Highest Concern/Impact/Satisfaction for select demographic groups, we chose to only focus on “Very” or “Significant” responses. Although a “somewhat” response indicates some level of
concern/impact/satisfaction (as compared to a “not at all”), it was decided that a “Very” or “Significant” response was more indicative of a respondent’s paramount concern. Thus, all responses for select Demographic Groups represent the percentage or total of respondents indicating “Very or “Significant” for the specific category.
Additionally, further grouping was performed on both Household Income and Race/Ethnicity for the ease of analysis and interpretability.
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Household Income was re-structured into the following three groups:
Less than $50,000
$50,000 - $100,000
$100,000 +
Race/Ethnicity was re-structured into the following two groups:
White or Caucasian
All other Races/Ethnicities
1.6.2 Open-Ended Questions
The survey contained six open-ended questions. Open-ended responses were categorized by topic area and analyzed for emerging themes. A word cloud has also been created to highlight key categories. The full text of
responses will be available in the Appendix.
1.7 RESULTS
1.7.1 Overview
The English version of the survey was initiated on August 31st and closed on October 11th. The English version of the survey had 413 visitors and 331 responses. However, because of duplicate responses, only 328 responses were
included in the analysis. Engagement with the survey generated over 16 hours of public comment. 290 of the respondents indicated that they lived or worked in a City zip code, while 41 responses came from a zip code outside of City limits. All responses, both in-City and out of City zip codes were analyzed. The Spanish Version of the survey,
published two weeks after the English survey, had no respondents. The phone-in option was not utilized either.
1.7.2 Demographics
Respondents were asked to answer basic demographic information including age, housing status, income and ethnicity. These questions were asked to assess how well the survey respondents reflected the actual community make-up of San Luis Obispo. Respondents were asked to identify what 10-year age block they belonged to. The
highest percentage of respondents were 18-24 (26%), followed by 25-34 (16%), 35-44 (17%), above 65 (15%), 45-54 (13%), and 55-64 (13%).
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Half of respondents were homeowners (50%), 44% were renters, and 6% selected “other”.
The most common household income selected by respondents was $100,000-149,000 (58), followed by 200,000 or more (33). In contrast, 30 respondents selected the lowest income bracket (less than 10,000), and 14 selected the second lowest income bracket: $10,000-14,999.
Respondents most commonly described themselves as White or Caucasian (234), followed by Asian (32), Hispanic, Latino or Spanish origin (29), Black or African American (9), American Indian or Alaskan Native (8), and Native Hawaiian or other Pacific Islander (2). It is worth noting that 42 respondents chose “prefer not to say” when
describing their racial identity.
As a reference point, Demographic results from the survey were compared with the 2018 American Community Survey to determine if the survey respondents over or under represented the demographics of SLO residents. Details
on representation are noted below.
Demographic 2018 American Community Survey (%) Community Priority Survey Results (#, %) Over or Under Represented?
Housing Situation
Homeowner 68% 164, 49.5% Under
Renter 35% 146, 44% Over
Age
Under 18 13.1% 0, 0% Under
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Demographic 2018 American Community Survey (%) Community Priority Survey Results (#, %) Over or Under Represented?
18 - 24 34.9% 80, 25% Under
25 - 34 13.6% 51, 16% Over
35 - 44 8.3% 53, 16% Over
45 - 54 8.7% 42, 13% Over
55 - 64 8.9% 40, 12% Over
Above 65 12.5% 46, 14% Over
Ethnicity/Race
American Indian or Alaskan Native .3% 8, 2% Over
Asian 5.6% 31, 9% Over
Black or African American 2.0% 5, 2% Equal
Hispanic, Latino or Spanish origin 18.3% 23, 7% Under
Native Hawaiian or Pacific Islander .1% 2, 1% Over
White or Caucasian 70.7% 237, 72% Over
Other .2% 3, 1% Over
Household Income
Less than $10,000 11.6% 30, 9% Under
$10,000 - $14,999 7.3% 15, 5% Under
$15,000 - $24,999 11.2% 9, 3% Under
$25,000 - $34,999 6.3% 15, 5% Under
$35,000 - $49,999 11.2% 17, 5% Under
$50,000 - $74,999 15.2% 30, 9% Under
$75,000 - $99,999 10.8% 29, 9% Under
$100,000 - $149,999 12.8% 59, 18% Over
$150,000 - $199,999 5.8% 32, 10% Over
$200,000 or more 7.8% 33, 10% Over
Hispanic, Latino or Spanish origin were the most underrepresented when compared to the 2018 American
Community Survey. The survey respondents were also younger than the 2018 American Community Survey results. The two youngest age groups were underrepresented, especially those under 18 whom were not represented at all. All other age groups were slightly overrepresented. 12 respondents chose “prefer not to say” on this demographic
question. Otherwise, all results were within 4 percentage points of the 2018 American Community Survey showing a successful sample of SLO demographics.
The demographic question that most respondents declined to answer was about total household income with 57 choosing “prefer not to say.” The highest three income brackets were overrepresented while lower income brackets were underrepresented compared to the 2018 American Community Survey results. This could be correlated with the
higher percentage of survey respondents in younger age groups, who tend to make less money than older Americans later in their careers.
All respondents had to choose an answer when asked about their housing situations. The options included “Homeowner, Renter, and Other.” Homeowners were under represented by respondents while renters were over represented. 19 chose “Other” to specify their housing situation. Some of them were students living at home or in student housing.
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1.7.3 Open-Ended Questions
Details for each open-ended question are provided below:
Of the open-ended questions, Question 5, “If there are other community issues not listed above that you are
concerned about, please provide them here,” had the most responses (153).
Question 16, “What climate change adaptation and community resilience topics are you interested in learning more about?” had the 2nd highest number of responses (105).
Question 14 garnered the third most responses (95), and asked “Do you have suggestions for how the City of San Luis Obispo can improve response efforts (to hazards)?”
Question 13 had the 4th most respondents (83) and “Do you have any comments to share regarding how you were affected by past hazards and/or city response efforts?”
Question 7, “If there are other climate change impacts not listed above that you are concerned about, please
provide them here,” had 77 responses.
Questions 9 and 11 had the lowest number of respondents (54) and (37) respectively. Question 9 asked for additional areas impacted by climate change of concern. Finally, question 11 asked for additional hazards that respondents have been personally affected by over the past 1-3 years.
Responses to key open-ended questions are discussed in detail in the results below.
There were 604 total responses to open-ended questions.
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1.7.4 Core Questions
WHICH OF THE FOLLOWING ISSUES ARE YOU CURRENTLY CONCERNED ABOUT?
Overall Results
Respondents were most concerned about issues that are affecting their day-to-day life in 2020. As noted on the Figure above, this includes COVID-19, Air Pollution, Job Security, Social Equity and Affordable Housing. The strong concern for COVID-19 is not surprising; during the time period the survey was open, COVID-19 still had California
counties in various stages of quarantine/lockdown. Additionally, the already competitive housing market in the state went through changes as some cities saw rents shift unpredictably. Furthermore, the summer saw high periods of
social unrest as cases of police brutality and racial injustice were brought to the national spotlight. Beginning in August, wildfires broke out across the state following dry conditions, lighting, high-winds, and extreme heat. 2020 has also seen the largest wildfire in California’s history, and the multiple fires occurring caused poor air quality for wide swaths of the state including the central coast.
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Variation by Housing Situation
As noted in the graph above ], renters and homeowners shared a similar amount (+/- 1 - 4%) of concern for a variety of key issues - Water Pollution, Tree Health, COVID-19, Healthy Food, Earthquakes, and Air Pollution. The three areas
of greatest misalignment were Affordable Housing (68% v. 36%); Social Equity and Justice (63% v. 44%); and Transportation Affordability and Accessibility (40% v. 28%). The variation in Affordable Housing is understandable given the status of the respondents as “renters”’; homeowners are likely to be less concerned about housing
affordability due to already owning a home. The variation in Social Equity and Justice is unclear, but could be connected to the age of the respondents (i.e. a correlation between age and homeowner status) or another unifying variable. The same could be said for Transportation Affordability and Accessibility with the added caveat for income.
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Overall, the top three concerns for homeowners are COVID-19 (62%), Water Pollution/Stream Health (48%), and Air Pollution (47%). The top three concerns for renters are Affordable Housing (68%), COVID-19 (65%) and Social Equity and Justice (63%).
Variation by Race/Ethnicity
Level of climate concern between different racial and ethnic groups (in this case, Caucasian v. All other Races/Ethnicities) was fairly uniform on most key issues. The largest divergence occurred for Job Security and Economic Vitality (39% v. 53%); Air Pollution (55% v. 48%); and Transportation Affordability and Accessibility (36% v.
43%). Overall, the top three concerns for White or Caucasian respondents are COVID-19 (66%), Social Equity and Justice (61%) and Affordable Housing (56%). For participants identifying as one or more other races, their top three
concerns are identical with some variation in level of concern (61%; 58%; 57% respectfully).
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Variation by Income Group
Responses by income group are noted in the figure above. There is great variability in the level of concern Individuals
have for key climate and adaptation subjects. The one exception to this observation is a clear concern for COVID-19 across all income groups. Unsurprisingly, individuals within the lowest household income group (“Less than $50,000), expressed a much higher level of concern for Affordable Housing (68% v. 51%, 40% respectfully); Job Security and
Economic Vitality (56% v. 41%, 38%); and Transportation Affordability and Accessibility (46% v. 29%, 27% respectfully). Individuals within the other two income groups ($50,000 - $100,000 and $100,000 +) were more aligned in their levels of concern; the one main exception for this is concern for Water Pollution/ Stream Health (63% v. 42%).
Overall, individuals with a household income of less than $50,000 were most concerned about COVID-19 (71%); Affordable Housing (68%); and Social Equity and Justice (62%). Individuals with a household income between $50,000
- $100,000 were most concerned with Water Pollution/ Stream Health (63%); COVID-19 (61%); and Air Pollution (56%). Individuals with a household income of $100,000 or more were most concerned with COVID-19 (61%); Social Equity
and Justice (52%); and Air Pollution (48%).
Variation by Age
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When evaluated on the dimension of age, individuals expressed some similar concerns. COVID-19 continues to be a trend with the majority (50% +) of individuals expressing a high level of concern. More specifically, individuals above the age of 65 were most concerned with COVID-19 (76%); individuals between the ages of 45 and 54 were the least
concerned with COVID-19 (55%).
Aside from COVID-19, other top concerns included Social Justice and Equity – a first or secondary concern for individuals within the following age groups: 18 - 24; 35 - 44; and 45 - 54. Individuals between the ages of 25 and 34
are also concerned about Social Justice and Equity (56%), but their paramount concern is Affordable Housing (75%). Individuals above the age of 65, on the other hand, are the least concerned about Social Equity and Justice (37%); after COVID-19, they are most concerned about Air Pollution (61%).
Open-Ended Responses
Question: If there are other community issues not listed above that you are concerned about, please provide them here.
Respondents were also able to write in other concerns that were not addressed above. 153 respondents wrote in a concern. The most repeated write-in concern involved homelessness. Selected responses include:
“Homelessness and the lack of focus our city official have on dealing with the issue.”
“How is the community taking care of the House-less population?
What are the options for those that do not have homes during the pandemic and unhealthy air conditions due to
natural disasters (I.e. fires)”
“The growing number of homeless in our downtown open spaces and doorways. Downtown is the heart of SLO
and central to its vibrancy.”
“Homelessness is impacting the waterways & Spot fires. Hard facts to face but true.”
“providing services from homeless and mentally ill persons in the county”
Concerns that were repeated by multiple respondents include issues of police brutality and police funding. Select responses:
“Systemic racism and our bloated county Sheriff’s budget,”
“Racism, police brutality, republican takeover using big money for our local candidates which will diminish the
focus on environmental and justice concerns,”
“Addressing and defunding workplaces and laws that uphold systemic racism. Defund the police in order to allocate funds towards issues like the ones listed above.”
“Overfunding on police--defunding is necessary.”
“I live by Santa Rosa Park and the homeless population is very disrespectful of our property. The creek that runs
through our backyard is littered with their trash and they are constantly stealing things out of our yard. The police are not helpful with the issue whatsoever. The police are an entirely useless organization and are especially terrible here in SLO.”
“Police Department suppressing free speech rights by tear gassing people, over-charging protest organizer, failure to files charges against individuals who drove cars into pedestrians.”
Other concerns that were repeated multiple times include cycling and transportation issues.
Selected responses:
“Walkability”
“Stop wasting money on changing roads to accommodate bike lanes. Instead (sic) focus on adding busses and repairing our streets. Do not take away our street parking to make a bike lane.
“Infrastructure and road building”
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The graphic (shown below) is a word cloud generated from responses the open-end question. As the Word Cloud illustrates, housing and homelessness were two salient topics for respondents.
Which of the following climate change impacts are you concerned about?
Overall Results
Respondents were very concerned about most of these climate impacts. Only Flooding and Storm Damage saw more respondents choosing “Not at all” or “Somewhat”. Wildfires and Wildfire Smoke had the most concern, likely related to the volatile 2020 wildfire season in California that brought that state’s largest wildfire to date and many days of unhealthy air quality.
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Variation by Income Group
When evaluated by income group, all groups, regardless of income, expressed strong concern about Wildfires (80%,
81%, 80% respectfully); however, it is interesting to note that individuals in the lowest income group are more concerned with Wildfire Smoke than Wildfires as a climate category (80% v. 84%). Individuals within the lowest income group are also most concerned about Hotter Temperatures and Heat Waves (78%) and are significantly more
concerned about Sea Level Rise than individuals in other income categories. In comparison, individuals within the highest income group are most concerned about Drought and Decreased Water Supply (76%); their tertiary concern is Wildfire Smoke. Individuals within the middle-income group share similar concerns with some variation in percentage (71% for both).
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Variation by Age Group
When evaluating climate concern by age, a few patterns emerge. Across the board, individuals are most concerned
about Wildfires. Within that category, individuals between the ages of 18 and 24 are most concerned (88%), followed by individuals between the ages of 25 and 34 (86%). There is greater variation when evaluating individual’s secondary concerns. Wildfire smoke is the second highest concern for individuals between the ages of 18 – 24 and 25 – 34. For
all other age groups, their second highest concern is Drought and Decreased Water Supply. The greatest variance in concern among age groups is with Sea Level Rise. Individuals between the ages of 18 and 24 have the highest level of concern (65%), with individuals above the age of 65 expressing the least amount of concern (17%).
Variation by Race/Ethnicity
Climate concerns between different racial and ethnic groups (in this case, Caucasian v. All other Races/Ethnicities) was fairly uniform on a majority of issues (+/- 6%) – Drought and Decreased Water Supply (78% v. 75% respectfully); Hotter Temperatures and Heat Waves (75% v. 73%); Wildfires (84% v. 79%); and Wildfire Smoke (79% v. 73%). The
largest divergences occurred for Flooding and Storm Damage (24% v. 36%) and Sea Level Rise (37% v. 49%). Regardless of racial or ethnic identify, all individuals noted the same top concern: Wildfires. Secondary and tertiary
concern varied slightly – Wildfire Smoke (79%) and Drought and Decreased Water Supply (78%); vs. Drought and Decreased Water Supply (75%), Hotter Temperatures and Heat Waves (73%), and Wildfire Smoke (73%).
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Variation by Housing Situation
Climate concerns among individuals in different housing situations varied slightly. The top concern for Homeowners
and Renters is Wildfire (72% v. 85% respectfully). Secondary concern for these two groups deviated; renters are more concerned about Wildfire Smoke (84%); homeowners are more concerned about Drought and Decreased Water Supply (68%). Individuals identifying their housing situation as “Other” had four competing interests at 79% - Drought
and Decreased Water Supply, Hotter Temperatures and Heat Waves, Wildfires, and Wildfire Smoke. The greatest divergence on level of concern occurred between Homeowners and Renters on the issue of Sea Level Rise: 51% of renters expressed concern versus only 22% of homeowners.
Open-Ended Responses
Question: If there are other climate change impacts not listed above that you are concerned about, please provide them
here.
There were 77 responses to this question. Answers were categorized by topic area. The four most prevalent themes discussed by respondents were:
1) Biodiversity and Health of Inland and Marine Ecosystems
2) impacts to Agriculture & Food Systems
3) Water Supply
4) Social Inequality.
Biodiversity and impacts to wildlife and their habitats were key concerns for respondents. Concerns were raised about
both inland and marine ecosystems. Key concerns for marine ecosystems included plastic pollution and ocean acidification. Respondents were also concerned with the impacts of climatic changes on agriculture and how agricultural changes might impact food supply and access. Water supply was also frequently mentioned. Over half of comments related to water discussed over-building and the impacts of new development on water supply. Comments also mentioned modified agricultural practices, water conservation, use of non-potable water and desalinization as potential solutions. Social inequality was another key issue. Comments in this category mentioned social justice, systemic and environmental racism, environmental justice, issues of representation, impacts to low
income communities, and wealth inequality.
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Subject Area Issue Frequency of Mentions
Environmental impacts
Biodiversity and Health of Inland and Marine Ecosystems 22
Pests and Diseases 4
Negative Environmental Impact of Development 2
Water Water Supply 8
Agriculture Agriculture & Food Systems 11
Human Systems
Social Inequality 7
Economy 4
Public Health 3
Energy & Infrastructure Energy 4
Transportation 4
Natural Disasters
Extreme Weather 5
Mudslides/Mudflows 3
Wildfire or forest management 3
Temperature 2
Other Climate Change is not occurring or should not be addressed by City 6
Responses to the open-ended question were also used to generate a Word Cloud (shown below). The Word Cloud
illustrates the prevalence of words such as water, agriculture, environment, native, wildfire, food, etc. The frequency of these themes indicates that topics related to environment, water and agriculture are common concerns for respondents.
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HOW CONCERNED ARE YOU THAT CLIMATE CHANGE WILL IMPACT ANY OF THE
FOLLOWING AREAS?
Overall Results
Respondents chose “Very Concerned” with less frequency for this question than previous questions. There is high concern about Utility Disruptions and Power Outages which aligns with the context of this survey’s timing. Summer
2020 brought extreme heatwaves in the state and the California Independent System Operator issued multiple “flex warnings” statewide to conserve energy and blackouts occurred as demand for electricity to combat extreme heat increased. Customers in Northern San Luis Obispo county experienced outages in August 2020. Additionally, Pacific
Gas & Electric has also participated in Public Safety Power Shutoffs as a wildfire prevention tool that also created utility disruptions. High concern around Employment and Job Security and Evacuations also fits trends seen in earlier
questions and align with later concerns about Wildfires and Wildfire Smoke.
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Variation by Income Group
As noted on the graph above, regardless of income, all individuals expressed the highest level of concern for Public Health and Safety (70%, 64%, 60% respectfully). Secondary concern varied slightly. After Public Health and Safety, individuals with household incomes of less than $50,000 or more than $100,000 were most concerned with Utility Disruptions and Power Outages. In comparison, individuals in the middle-income group ($50,000 - $100,000) had a
secondary concern of Evacuations. The greatest divergence in level of concern occurred between individuals with a household income of less than $50,000 and more than $100,000 on the issue of Transportation Disruptions. Individuals within the lower income group had the highest level of concern among the three groups for this category
- 42%. On the other end of the spectrum, the opposite was true: individuals within the highest income group had the lowest amount of concern – 14%.
Variation by Age Group
When viewing concern for climate change impacts by age, a few patterns emerge. Across the board, individuals are most concerned about climate’s potential impact on Public Health and Safety. Within that category, individuals between the ages of 18 and 24 are most concerned (75%), followed by individuals between the ages of 25 and 34 (73%). Utility Disruptions and Power Outages are also a common concern among the age groups, with at least 50%
of individuals in five age groups (all except individuals between the ages of 55 and 64) expressing concern.
Omitting Public Health and Safety, individuals between the ages of 18 and 24 are most concerned about climate’s potential impact on Evacuations (66%); and Utility Disruptions and Power Outages (61%). Individuals between the
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ages of 25 and 34 are also concerned about the same two categories with some variation in level of concern (57% and 69% respectfully). Individuals between the ages of 35 and 44 share a similar level of concern for Utility Disruptions and Power Outages (57%); they are also concerned about Access to Beaches and Open Space (42%).
Individuals between the ages of 45 and 54 are concerned about Utility Disruptions and Power Outages (50%), followed by Evacuations (29%). Individuals between the ages of 55 and 64 are also concerned about Utility Disruptions and Power Outages (48%), in addition to Evacuations (33%). Finally, individuals above the age of 65 are
concerned about Utility Disruptions and Power Outages (50%) and Evacuations (37%).
Variation in Race/Ethnicity
Regardless of racial or ethnic identify, individuals expressed similar levels of concern for two potential climate change impacts: Public Health and Safety (69% v. 64%, respectfully) and Utility Disruptions and Power Outages (56% v. 67% respectfully). Tertiary concerns were also the same – Evacuations (49% for both). The greatest divergence between groups occurred for Transportation Disruptions; only 24% of White or Caucasian respondents expressed concern
compared with 42% of respondents of respondents identifying as all other races and ethnicities.
Variation by Housing Situation
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When viewed through a housing situation lens, a few patterns emerge. Despite the variability, all respondents regardless of housing situation are concerned about Public Health and Safety, with individuals in the “Other” category reporting the highest level of concern at 79%. This same group expresses the same level of concern for Evacuations.
Both renters and homeowners also list Utility Disruptions and Power Outages as a secondary concern (50% and 67% respectfully). This is a tertiary concern for individuals in “Other” alongside Transportation Disruptions. In terms of priority, homeowners and renters share a similar view on their concern for Evacuations (37% v. 59% respectfully). Of
all the questions so far, this answer elicited the highest level of variability in level of concern; the smallest variation among levels of concern is for Utility Disruptions and Power Outages at 4%.
Open-Ended Responses
Question: If there are other areas impacted by climate change not listed above that you are concerned about, please provide them here
Respondents were also able to write in other concerns that were not addressed above. 54 respondents wrote in a concern.
6 of the respondents brought up concerns over how marginalized communities would feel climate impacts first.
Selected responses:
“I am concerned about how climate change will impact low income communities and communities of color first.”
“Health effects upon the poor and elderly, especially during the summer.”
“We need a community plan to support frail elders and people with chronic illness who are reliant on electricity, and cannot be without power. Example: people w/ lung disease, who use oxygen, electric beds, breathing assist
machines. The rolling blackouts that are happening in CA (due to fire and maxing out of the power grid) are devastating for this portion of our community. We need an organized, local government plan to identify and
support these folks.”
8 Respondents brought up concerns about biodiversity, natural resources, and wildlife. Selected responses:
“Access to food and use of agricultural resources, impacts to marine life and fisheries (including for food)”
“Again, that we are not considering the impact on local wildlife” or preparing to create safe zones for animals
(inland & marine)
“Natural resource conservation is being impacted by the lack of regional consensus about conservation and habitat restoration goals as the climate changes. SLO has an opportunity to build on leadership and successes
from within City government to emphasize natural resource conservation measures in a changing climate.”
“Loss of biodiversity, climate refugees, natural resources”
8 Respondents brought up concerns about agriculture and/or local food access:
“Weather patterns, heat waves, and quality of air and water affecting the ability to grow food.”
“crop yield and tourism”
Remaining responses ranged from denying the city’s role in responding to climate change, concerns over utilities or utility shut offs, concerns over evacuations, from where evacuees can go to how to handle refugees coming to the
SLO region. A few respondents brought up concern for “hope” in the future.
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Open-ended responses were used to generate a Word Cloud (shown below). The words shown were frequently used by respondents.
WHICH OF THESE HAZARDS HAVE YOU BEEN PERSONALLY AFFECTED
BY IN THE LAST 1-3 YEARS IN THE CITY OF SLO?
Overall Results
This question has more respondents reporting they have not been personally affected by about half of these impacts in the last 1-3 years. The most significantly reported impacts were of Wildfire Smoke, Hotter Temperatures and Heat
Waves, and Air Pollution which matches the trends in other questions and references the context of events in 2020 (i.e. wildfire and extreme events). Even when wildfires do not occur in the city boundaries, impacts of wildfire smoke and air pollution affect many residents somewhat or significantly which explains why “Wildfire” has less significant
direct impact for respondents than “Air Pollution” and “Wildfire Smoke.’
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Variation by Age Group
In terms of Hazards, all age groups have been quite impacted by Wildfire Smoke and Hotter Temperatures and Heat Waves. Within these two categories, individuals between the ages of 25 and 34 were most impacted (61% and 57%, respectfully). Individuals above the age of 65 indicate the lowest level of impact for these two categories (46% and
37%, respectfully). Other impactful hazards include Wildfires - with individuals between the ages of 25 and 34 reporting the highest level of impact at 29%, followed by individuals between that ages of 35 and 44 at 26% - and Air Pollution – with individuals between 25-34 and 55-64 each expressing the highest impact – at 33%. Erosion, Extreme
Rainfall, Flooding, and Tule Fog were very rarely listed as a high impact for individuals across the age groups.
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Variation by Race/Ethnicity
In terms of racial and/or ethnic identity, all groups expressed a high level of impact for Wildfire Smoke (59% and 53% respectfully) and for Hotter Temperatures and Heat Waves (52% for both). A tertiary concern was Air Pollution (34% and 29%). Similar to the other analyses for this question, respondents did not express high levels of impact for Erosion, Flooding, Extreme Rainfall or Tule Fog. The greatest divergence between groups occurred for Drought and
Water Supply; Caucasian or White respondents reported a higher level of impact – at 18% - than individuals of other races/ethnicities – at 10%.
Variation by Income Group
From an income perspective, individuals within the lower income bracket were most impacted by Hotter Temperatures and Heat Waves (58%), followed by Wildfire Smoke (53%). Individuals in the other two categories expressed a similar level of impact for Hotter Temperatures and Heat Waves (46% and 44% respectfully), with a
higher level of impact for Wildfire Smoke (63% and 50%). In fact, individuals in the middle-income group express the highest level of impact for Wildfire Smoke. Other shared impacts include Air Pollution (35%, 27%, and 29%
respectfully) and Wildfires (24%, 25% and 17%).
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Variation by Housing Situation
Homeowners, renters, and individuals indicating “Other” report being most impacted by Wildfire Smoke (45%, 60%, and 58%, respectfully), followed by Hotter Temperatures and Heat Waves (41%, 55%, and 47%, respectfully). Aside from these two categories, renter and homeowners report being more impacted by Air Pollution than Wildfires (26% v. 36%; 15% v. 26%); individuals indicating “Other” report the opposite (26% v. 32%).
Open-Ended Responses
Question: If there are other hazards that you have been personally affected by in the past 1-3 years in the City that are not listed above, please provide them here.
There were 37 responses to this question. Of those responses, 10 discussed climate related hazards. The remaining 27
discussed other community issues not directly applicable to climate change. Related responses discussed the following:
Mortality of trees that were weakened by drought. Tree caused damage to the home and increased cost of air conditioning due to loss of canopy.
Extreme 116 degree heat
Nearby wildfires and the impacts of smoke on an asthmatic
Experience with Lyme Disease
Landslide from extreme rainfall
Air pollution that lead to the development of asthma
Dust
Power outages
Invasive species
Loss of biodiversity affecting people psychologically and economically.
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Responses to question 11 were used to generate a Word Cloud (see below).
FOR EACH HAZARD THAT YOU WERE AFFECTED BY, PLEASE RANK YOUR LEVEL
OF SATISFACTION WITH THE CITY’S RESPONSE.
Overall Results
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Open-Ended Responses
Question: Do you have any comments to share regarding how you were affected by past hazards and/or city response efforts? Please describe specific hazard, location, and response
Write-in answers to this question demonstrate that respondents are either not clear on how much the city can do in responding to climate impacts, don’t believe the city can respond to impacts that they few as “natural” or at the
state/federal scale or they do not know how the city responded and wish for more publicity about city response efforts. Because of these frequently cited opinions, multiple respondents indicated they used “Not at all satisfied” to indicate “not applicable” or they skipped responding at all. For these reasons, write-in responses are a more useful
analysis than the absolute numbers. 83 respondents wrote in a short answer.
Select responses that express doubt or confusion about the city’s ability to respond:
“Several of the above items are caused by nature and the city can’t do anything about them so they should not even have been included.”
“I cannot see how the city could do anything about fires, floods, fog and rain. The city can and should focus on
eliminating trash and waste in our local parks and waterways. That will have a huge impact on its citizens' outlook on our government taking care of the city.”
“Let's act now to reduce the burnable debris around out (sic) homes and stream beds.”
“I don’t think the city can do anything to control or improve these items except for provide infrastructure that
allows emergency responders to quickly and safely access the entire population. In that regard the city has actively made response times and access to core populations worse by converting roadways to bicycle paths and failing to add lanes to major thoroughfares. I think the city really needs to reassess its willingness to sacrifice
human lives in the name of environmentalist ideals. When someone has a stroke every minute of delay in transport to the hospital costs that person brain function and treatment options. Additionally these alternative modes of transportation have no ability to help facilitate business growth or commerce, and as such provide no return on the funds the city invests in them.”
“I really don't see how the City can "respond" to some of these. Air pollution from what? If wildfires, not much the City can do apart from abatement and building codes already in place. Auto pollution is minimal. And City Hall cannot dictate the weather.”
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“I'm not aware of the City's response to any of the above listed items except to say the more growth, housing, etc. that occurs the more air pollution and lack of water supply will be factors in everyday life. As well as infrastructure that cannot support the housing growth all around the city.”
“I used "Not at all satisfied" to indicate more of "not applicable" Air pollution is being worked upon by the City, and awareness of the need for conservation of water was an ad campaign and a hotline, both appreciated. The effects of the others I cannot see the City's responsibility to. In my case only.”
“I only rated a few factors because many of these issues are not truly under local influence/control. The City has done a good job addressing our flood control system. More needs to be done about wildfire prevention but a
significant challenge is the amount of overgrown vegetation on private property or land just outside the City's footprint.”
“In general, I feel the city hasn't really acknowledged it's general resident experiences with climate change. Too much focus on bike lanes and ignoring the less glamorous/ youth-focused, and middle/upper class side of being impacted by climate change.”
“I'm not sure how to respond to some of these questions where I do not have a direct experience, and as a result don't have a level of satisfaction to report. I believe the City leadership's push for climate action, sustainable
transportation, affordable housing, and protection of open space are all in the right direction.”
“You should have had a "not applicable" column. There is little the City can do about hot temperatures or wildfire smoke drifting into the area. Drought and water supply is something the City can control. Constantly raising
water rates while allowing hundreds of new homes it NOT the way to respond.”
“What is the city doing for any of these? If they are doing something, they sure aren't doing a good job publicizing what they are doing.”
Select responses that offer more concrete feedback:
“Storm drain clearance especially on the north end of the city near Loomis Street is sometimes lacking and more frequent patrols by city personnel to this area would be appreciated.”
“Appreciate the notifications we get through Twitter and other platforms.”
“Address fire prevention like the Native Americans and how we used to. Prevent forest fires.”
“City could do more to reduce water use - encourage lawn reduction, including on City properties.”
“The city has used a wide brush to paint very high fire hazard and should be more specific/precise in classifying fire hazard. A city perimeter approach would be more effective and appropriate. Over-classifying can have dire effects on residents ability to obtain fire insurance. Just like keeping areas in flood zones that have been
mitigated is a problem.”
“The potential for water shortage is ignored when the city approved extensive new housing. Otherwise these developments would have been disapproved. The city says one thing but does another with respect to this topic.”
“While the firefighters have indeed been heroes in this scenario, the city need to undertake extreme conservation
measures, plant more trees to increase air quality, install solar throughout the town, enforce xeriscaping and the like. I do appreciate the city/county air report.”
“Stonewalling on the Lake Dredging project is unacceptable.”
“Keep beaches open for locals during heat waves.”
‘I actually was not aware of the City's response at all to any of these issues.”
“Last winter when highway 5 was closed due to snow. The freeways and highways were blocked for HOURS and HOURS because we only have one or two routes to use in Southern California and the Central Coast.”
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“What is the city doing to capture and utilize the very little rain we get each year? How much of it are we losing to runoff in our ocean? What is the city doing to implement a carbon free grid by 2030? How can we take wisdom and advice from our local indigenous people to better understand working with the environment?”
“My property is located within a flood zone. Mitigations, such as creek debris clearance, have been successful (so far!). Though many residential neighborhoods back up to steep, somewhat denuded hills, there have not been any significant mudflows (so far!). There is an inadequate supply of N95 masks which are necessary when doing
errands during periods of hazardous air quality.”
“Allowing 75 foot buildings downtown adds to the heat zone of the downtown corridor”
“I'm glad a notice has been put out about the air pollution hazards. We need strong messaging from our leadership to help us through challenges.”
“heat mitigation in low income housing is not being taken seriously.”
“I do not think, in a town where the majority do not have AC, we (the city) are ready for extreme heat.”
“It wasn't apparent to me that the homeless had options to shelter in a cool/clear air space”
“Hotter temperatures, but the city does not have shade structures in many areas.”
“Flooding. If we and our neighbors didn't go out and clean the storm drains when it rains hard, multiple yards
would be underwater.”
“Wildfires: Reverse 911 works really well but most of my friends didn't know about it so trying to get the word out
better. The Reverse 911 message also needs to be more clear including identifying the threat.”
Responses to this question were used to generate a word cloud (see below).
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HOW WOULD YOU PRIORITIZE THE FOLLOWING ACTIONS IN THE CITY OF SLO?
Respondents were asked to prioritize actions in the City of San Luis Obispo. Housing was most frequently listed as a
number one priority; housing was chosen as the top priority 122 times or by 40% of respondents. Land Preservation, another priority topic, was selected as the number one priority 89 times or by 30% of respondents. Selected as the number one priority less frequently were Agricultural Land Preservation (selected 29 times or by 10% or respondents),
Public Transportation (21 times or 7%), Trails (16 times or 5%), Parks (14 times or 5%), and Space for Business (9 times or 3%).
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City of San Luis Obispo Baseline Conditions Report B-32
WHAT CLIMATE CHANGE ADAPTATION AND COMMUNITY RESILIENCE TOPICS ARE
YOU INTERESTED IN LEARNING MORE ABOUT?
There were 104 responses to this question. The most common topical areas mentioned by respondents were transportation, energy, and the environment. Water, wildfire, housing and social issues were also prevalent topics, in
addition to agriculture, temperature changes, development, and emergency management. Issues related to climate change mitigation, waste and pollution and the economy were also mentioned. Multiple comments indicated interest in any topic related to climate adaptation and resilience. There were also several comments that the City should not
be pursuing this topic. The table below summarized the approximate number of mentions for each topical area and topics suggested by respondents.
Topical Area Topics Mentions
Transportation Electric vehicles and charging
Public transportation
EV charging for apartment renters
Active Transportation/bikeability/walkability
Reducing emissions from transportation
Traffic reduction
Walkable neighborhoods with access to services
Pro Con approach to transportation decisions
19
Energy Solar, wind and renewable energy sources
Solar for residential & existing homes
Require rooftop solar
Microgrids, batteries, & energy reliability
Affordable energy
Alternate technology such as trash to energy
Preventing early close of Diablo Canyon
Eradication of gas burning engines
15
Environmental
Protection Open Space/land preservation
Wildlife conservation
Air pollution
Urban forestry and trees to for urban cooling and societal benefits
Ecosystem-based adaptation
Saving beaches
Natural landscaping
15
Water Water conservation
“Integrated water resource management (intersections of flood management, water supply, watershed/habitat/GW protection, and water quality protection).”
Drought and water supply
Increasing infiltration
Community outreach on water conservation
11
Wildfire City wildfire mitigation efforts
Fire prevention & planning
Outreach to property owners at the wildland urban interface
Native land management practices and knowledge
10
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Ascent Environmental
Baseline Conditions Report City of San Luis Obispo B-33
Topical Area Topics Mentions
Fire safe building
Wildfire smoke
Prescribed burns
Fire response
Housing Balancing housing needs with land preservation
Affordable housing
Tiny homes
Housing for Cal Poly students
Repurposing existing developed land for housing
Off-grid housing
How climate change will impact housing prices
9
Social Issues How can the City encourage residents to contribute more?
Homelessness
Mass migration into City
How can the City avoid an increase in the wealth gap and unequal burden of climate change on marginalized communities?
Social equity and justice
Community outreach regarding personal actions such as water conservation, wildfire mitigation, carbon footprint reduction, etc.
How can the government better understand community wants and needs?
Covid-19
9
Agriculture Community gardens
Healthy food access
Local food
Soil health
Regenerative agriculture and permaculture
7
Temperature Changes Extreme heat leading to AC installation and impacts on grid
AC for schools and senior centers
Alternatives to AC
7
Development How can we accommodate growth in a less dense format?
Environmentally friendly development/ how can growth contribute to resilience?
Encouraging businesses and government to be environmentally conscious
Analysis of environmentally damaging industries and promoting more sustainable industrial practices
Resilient construction materials and landscaping
5
Emergency Management Faster warning systems for natural disasters
Planning for compound hazards
Pandemic and epidemic planning
Disaster preparedness and planning
Neighborhood resilience
Resilience
5
Climate Change Action City efforts to plan for and combat climate change 4
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Ascent Environmental
City of San Luis Obispo Baseline Conditions Report B-34
Topical Area Topics Mentions
Transitioning to a fossil fuel free society
Waste & Pollution Waste in parks and open spaces
Recycling and composting programs
Compost use in community gardens
Noise and light pollution
3
Economy Job security
Diversifying employment from tourism
2
Responses to this were also used to generate a Word Cloud. As the Word Cloud highlights, water, transportation, energy, housing and land were among the frequently used words.
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Survey Strategies for Resilience
August 26, 2021, 11:41 AM
Contents
i.Summary of registered responses 2
ii.Survey questions 4
iii.Individual registered responses 5
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Summary Of Registered Responses
As of August 26, 2021, 11:41 AM, this forum had:Topic Start
Attendees:51 January 29, 2021, 2:31 PM
Registered Responses:2
Minutes of Public Comment:12
QUESTION 1
What qualities of the SLO community most support long-term resilience? For example, social networks,
maintained infrastructure, local farms and food, creeks and flood control, adequate water supplies, air quality,
fire protection, etc.
Answered 2
Skipped 0
better community improved infrastructure more
QUESTION 2
We have heard community stories about what is needed to make our community strong. For example,
neighborhood food pantries, climate education, preparedness training, social cohesion, and air conditioning
during extreme heat. What ideas or strategies do you have for making our city more resilient?
Answered 2
Skipped 0
- energy implemented more other show
QUESTION 3
How can we protect the community members that are most vulnerable to climate change impacts? How do we
ensure that our process is equitable?
Answered 2
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Skipped 0
may more need people
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Survey Questions
QUESTION 1
What qualities of the SLO community most support long-term
resilience? For example, social networks, maintained infrastructure,
local farms and food, creeks and flood control, adequate water
supplies, air quality, fire protection, etc.
QUESTION 2
We have heard community stories about what is needed to make our
community strong. For example, neighborhood food pantries,
climate education, preparedness training, social cohesion, and air
conditioning during extreme heat. What ideas or strategies do you
have for making our city more resilient?
QUESTION 3
How can we protect the community members that are most
vulnerable to climate change impacts? How do we ensure that our
process is equitable?
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Individual Registered Responses
Name not shown
inside Neighborhood 1
January 30, 2021, 12:46 PM
Question 1
Since I moved to SLO in the mid-60's, I've observed that our City has
generally done an excellent job of governance. Infrastructure is constantly
being evaluated and improved as needed. City programs are varied and
serve the broad needs of the community. With community input,
Standards and Guidelines (although seemingly more and more unwieldy),
have been improved over time to protect our unique resources and guide
our physical development.
Question 2
Most of the above mentioned ideas sound very worthwhile. During this
Covid adventure, the efforts shown by the City, DowntownSLO, other
local community organizations and individuals, have greatly impressed
me as to the actual RESILIENCE of our amazing City. Continuing
education surrounding important issues is one of the key elements of
continued future success. Energy policies that have been implemented
show bold leadership that may show the way to other communities. We
can certainly look to other countries who have implemented forward-
thinking strategies for Resiliency. There are many great examples.
Question 3
Continue and expand educational information and outreach programs.
Maintain a budget item for emergency services for those that may be
most vulnerable as a result of climate change impacts. There may be the
need for a citizen advisory body to help determine priorities and
thresholds for support.
Name not available
inside Neighborhood 11
February 24, 2021, 12:13 PM
Question 1
existing infrastructure must be improved, better electricity, more natural
gas, sweep and clean the streets/gutters/sidewalks and bike paths,
more parking, better lighting, more police, trim trees
Question 2
More energy - keep the electricity on - back-up power when PSPS happen,
more natural gas for cooking/heating. Homeless are too aggressive.
Question 3
keep people healthy with better diets and more exercise, promote
"rugged individualism", people need to more self-sufficient.
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Climate Change Impacts on Community Organizations Survey Summary
Relation to the Safety & Community Resilience Element Update:
Traditionally, the General Plan had a Safety Element, with this update we are re-envisioning the
document as the Safety and Community Resilience element. The intention is to take a more
holistic approach by integrating community wellbeing and resilience in addition to the
traditional lens of public safety.
To integrate community resilience and wellbeing, we are reaching beyond a narrow focus on
physical infrastructure to consider social infrastructure – organizations and places that support
the networks of relationships in a community, social cohesion, and connectedness. There is
growing recognition that social capital – connectedness and trust within a community - is
important for building resilience to disasters and disruptions.[1] As the city prepares for an
increasingly unpredictable future, with greater incidence of disasters due to climate change,
social capital and the infrastructure that supports it becomes increasingly important.
The Climate Change Impacts on Community Organizations Survey will be used to include a
discussion of social infrastructure and community assets in the Safety and Community Resilience
Element, and a map of community assets.
Survey Purpose:
The survey is designed to help the city understand what parts of the community support social
cohesion, wellbeing, and disaster resilience. This information will inform the Safety and
Community Resilience Element update.
The survey can be used to understand:
• Well-trusted community spaces and organizations that the city can consider partnering
with in the future
• Resources that are missing that would support social cohesion and disaster resilience
• Resources/Assets that should be strengthened and invested in to improve social
cohesion, wellbeing, and disaster resilience
Survey Promotion
The survey was advertised through a press release, social media posts, flyers, and email
outreach. Flyers were posted on city transit and in city hall and were distributed at the
downtown Farmers’ Market.
Survey Participation
The survey was open from June16th through June 17th. There were 7 responses to the survey.
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The 7 organizations to respond to the survey were the SLO FoodBank, CAPSLO, The Salvation
Army, Jewish Community Center-Federation of San Luis Obispo, SLO Food Co-op, SLO Chamber
of Commerce, and Transitions-Mental Health Association.
Questions
The survey consisted of 6 questions, 4 of which were written response and 2 multiple choice.
Written Response/Open Ended
Question 1: What is the name of your organization?
Question 4: If your organization was impacted by one of the hazards listed above, how have
these impacts affected your operations and/or the population you serve?
Question 5: Does your organization have any emergency planning practices or protocols in
place to mitigate impacts on your operations during these events?
Question 6: Do you have any recommendations on how the City can help community
organizations become resilient to impacts to climate change?
Multiple Choice
Question 2: Which of the following climate change impacts are you concerned about affecting
your organization and/or the populations you serve?
Question 3: Which of the above-mentioned climate-related hazards has your organization been
personally affected by in the past 1-3 years?
Results
Overview
The objective of the questions asked was to gather information from core community
organizations in SLO City about the risk climate change poses to their organization and
operation.
Common Themes:
1. Community organizations are most concerned about the effects of:
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• Wildfire and associate impacts
• Increased Temperatures and extreme heat
• Large Storm Events and Flooding
• Long Term Drought
2. All 7 organizations have personally been affected in the last 1-3 years by wildfire and
associate impacts.
Responses to question 3: If your organization was impacted by one of the hazards listed above,
how have these impacts affected your operations and/or the populations you serve?
• “Many of our direct distributions, and distributions hosted by our agency partners are
held outdoors. This means our clients, volunteers, and staff have little to no protection
against extreme heat and poor air quality. We are also very concerned about PSPS events
and both our vulnerability as a food storage facility and the community's vulnerability.
We luckily received a grant to fund the addition of a generator to our main warehouse,
which will help us greatly in the event of a PSPS. But, we are still concerned about how
we will prepare ourselves to serve the community if/when it is hit with one.”
• Other impacts on operations that were cited were:
o Closure of children’s centers
o Aging adults needs support
o Homeless shelters
o Long term drought causing stress on water supply on property
o Work with local farmers to source fresh produce
o Increased housing costs
3. Many of the community organizations have an emergency planning practice or protocols in
place to help mitigate impacts on operations.
- These range from high level organization protocols to placing disaster and emergency
supplies in buildings and program sites.
4. In terms of recommendations for how the City can help community organizations become
resilient to impacts of climate change, organizations listed
- Education
- Creation of a general safety guide for natural disasters that businesses, non-profits, and
other organizations can utilize
- Supporting local sourcing and organic practices
- Communication
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The survey was open from August 12th through August 30th. There were 266 responses to the
survey.
Common Themes:
Community Strengths - Across all four scenarios, these assets were frequently mentioned:
1. Public Information (Disaster Information, Social Media, News)
a. 47 mentions accounting for 20% of responses.
2. Medical/Emergency Services (Public Safety)
a. 41 mentions accounting for 17% of responses.
3. Open Space/Trails
a. 31 mentions accounting for 13% of responses.
• Asset 1: Public Information (Disaster Information, Social Media, News) On average this
asset was rated as Very Important respondents listed receiving support from this asset in
the following types:
o Access to accurate and understandable information
o Informs about the current state of situation
o Enhances ability to prepare and mobilize
o Provides direction and recommendation
o Connects community members to resources
• Asset 2 Medical/Emergency Services on average this asset was rated as Very Important
respondents listed receiving support from this asset in the following types:
o Vaccines, injuries, aid
o Provides reassurance and “peace of mind” when services are well staffed, present,
and equipped.
o
• Asset 3 Open Space/Trails on average this asset was rated as Very Important/ Important.
Respondents listed receiving support from this asset in the following types:
o Improves Mental and Physical Health
o Outlet for activity or Relaxation
o Overall Fitness and Well being are supported
In addition to these specific assets, respondents frequently listed these assets:
- Community Service Centers (i.e.: Library, Cal Poly Campus, Churches, Pride and Diversity
Center etc.)
o 30 mentions, about 12%
- Multimodal Transit (bike lanes/ parking, pedestrian access, traffic control etc.)
o 25 mentions, about 10%
- Recreational Facilities (i.e.: Parks, Athletic Facilities, etc.)
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o 16 mentions, about 7%
- Local Economy/Business: 13 mentions, 5%
- Local Government: 10 mentions 4%
Types of Support Received - Across scenarios the types of support most frequently listed were:
- Emotional and physical security
- Opportunity to coordinate, prepare, and appropriately react
- Direction and recommendation on how to respond before, during, and after.
Gaps and Key Needs - Across scenarios these assets were frequently listed as missing:
In general
- Clear and effective communication
- Dynamic Facilities/Open Spaces
- Proactive attitude
Scenario 1
- Improve recreational amenities
- Increase of accessible transportation (more parking, more bus stops, bike/walk friendly)
- Resource security and Protection
Scenario 2
- Disaster Preparedness Manager
- Accurate information
Scenario 3
- Citywide plan
- Outreach and training
Scenario 4
- Resource Access (food, shelter, medical, recreational)
Scenario One: Normal Life
The following assets were listed for scenario one:
1. Community Service Centers
a. SLO County Library
b. The Mission
c. SLO Newcomers Group
d. Bishop Peak Elementary
e. SLO Village
f. Gala Pride and Diversity Center
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2. Disaster Information/Preparation
a. SLO Adult Education
3. Disaster Related Utilities
a. City Utilities/Infrastructure
4. Financial Support
a. SESLOC Federal Credit Union
5. Food Related Amenities
a. Farmers Market
b. Marigold Shopping Center
c. Trader Joes/Food 4 Less Shopping Center
6. Local Economy/business
a. Headstrong Fit
b. Equilibrium Fitness
c. Phoenix Books
d. Bang the Drum Brewery
e. Small Family-Owned Businesses
f. Bike Kitchen
7. Medical/Emergency Services
a. General Medical Care
b. Sierra Vista Medical Center
c. Up-to-date Hospitals
8. Multimodal Transit
a. Bike Paths
b. SLO Transit
c. Protected Bike Lanes
d. Pedestrian Hybrid Beacons
e. Pedestrian Oriented Sidewalks/Paths
f. Railroad Safety Trail
9. Open Space/Trails
a. Terrace Hill
b. Bowden Ranch
c. Cerro San Luis
d. West Cuesta Ridge
e. Laguna Lake
f. Bishop Peak
g. Feldsman Loop
h. Cuesta Park
i. South Hills Open Space
j. Edna Valley
10. Parking
a. Parking Garages
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b. Street Parking
c. Downtown Parking
d. Parking Accessibility throughout the City
11. Public Safety
a. Streetlights/Well Lit Areas
12. Recreational Facilities
a. SLO Swim Centers
b. Parks and Rec Kids Camp
c. City Parks
d. Damon Garcia Sports Fields
Results:
Asset Category Count
Community Service Centers 15
Disaster Information/Preparation 1
Disaster Related Utilities 1
Financial Support 1
Food Related Amenities 4
Local Economy/Business 5
Medical/Emergency Services 3
Multimodal Transit 18
Open Space/Trails 30
Parking 4
Public Safety 1
Recreational Facilites 14
Total 97
Scenario 1
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Scenario Two: Disaster Preparation
The following assets were listed for scenario one:
1. Community Service Centers
a. Community Centers
b. SLO County Library
c. Cal Poly University Campus
2. Disaster information/preparation
a. News
b. City Website, ReadySLO, EmergencySLO.org
c. Early Warning Systems (Sirens, Alerts)
d. Radio AM/FM Alerts
3. Disaster Related Utilities
a. Water Stations
b. Utilities
c. SLO Public Works
d. Mutual Aid
4. Education
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a. Soil and Regenerative AG Classes
5. Local economy/businesses
a. Target
b. The Mountain Air
c. Costco
d. Trader Joes
e. Miner’s Ace Hardware
6. Local government
a. SLO City and County Officials
b. SLO City
c. SLO County
7. Medical/Emergency Services
a. Fire Departments
b. American Red Cross
c. Health Department
d. EMS
e. Hospitals
f. Cal Poly Health Center
8. Multimodal Transit
a. SLO Airport
b. Personal Vehicles
c. Emphasis on Public Transportation
9. Social Media/News
a. KCBX Radio
b. Online Presence of SLO Community Members
Results:
Asset Category Count
Community Service Centers 3
Disaster Information/Preparation 18
Disaster Related Utilities 4
Education 1
Local Economy/Business 5
Local Government 4
Medical/Emergency Services 16
Multimodal Transit 4
Social Media/News/ Public Information 3
Grand Total 48
Scenario 2
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Scenario Three: During Disaster
The following assets were listed for scenario one:
1. Community Service Centers
a. City Hall
b. Church
c. SLO Library
d. Veteran’s Memorial Building
e. Schools
f. Ludwick Community Center
2. Medical/Emergency Services
a. SLO County and City Fire
b. SLO County and City Police
c. Search and Rescue
d. American Red Cross
e. Medical Reserve Corps
f. City Government
3. Social Media/news
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a. Social Media Groups
b. KSBY
4. Disaster Information/Preparation
a. Early Warning System
b. Pulse Point
c. EmergencySLO.org
d. Public Communication
e. ReadySLO.org
f. City Emails
g. KSBY
5. Shelters
6. Multimodal Transit
a. Airport
b. US 101 and Roadway Accessibility
7. Local economy/business
a. Costco
8. Local Government
a. SLO County and SLO City
Results:
Community Asset Count
Community Service Centers 7
Disaster Information/Preparation 10
Disaster Related Utilities 1
Local Economy/Business 1
Local Government 1
Medical/Emergency Services 15
Multimodal Transit 3
Recreational Facilities 1
Shelters 2
Social Media/News/Public Information 4
Grand Total 45
Scenario 3
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Scenario Four: Post Disaster
The following assets were listed for scenario one:
1. Local Economy/Business
a. Target
b. Small Business Development Center
2. Food Related Amenities
a. Grocery Stores
b. Pharmacy
c. Water and Food Supply
3. Recreational Facilities
a. The Pad Climbing
4. Local Government
a. SLO County Administration
b. City Government
c. County OES, City Manager, and Mayor
d. City of SLO
5. Social Media/News/Public Information
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a. City Agency Responsible for Disseminating Information
b. Timely Access to Service Providers
c. Newspapers
d. ReadySLO.org
e. SLO City Hall
f. Instagram, Twitter, Facebook
g. City Website
6. Community Groups
a. Local Non-Profit Organizations
b. Mutual Aid
c. Food Banks
7. Open Space/Trails
a. General Open Space
8. Financial Support
a. Workforce Recovery Grants
b. EDD
c. Insurance Companies
d. FEMA
9. Security and Protection
a. National Guard
10. Community Service Centers
a. Salvation Army
b. Churches/Religious Centers
c. The Center
d. SLO County Veteran’s Hall
Results:
Community Asset Count
Community Groups 4
Community Service Centers 4
Financial Support 4
Food Related Amenities 2
Local Economy/Business 2
Local Government 5
Medical/Emergency Services 6
Open Space/Trails 1
Public Safety 1
Recreational Facilities 1
Security and Protection 1
Shelters 1
Social Media/News/Public Information 12
Grand Total 44
Scenario 4
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Overview:
The Environmental Justice Survey for Community Organizations was intended to gather input on
environmental topics from organizations that serve vulnerable and/or disadvantaged
communities in the City of San Luis Obispo. More specifically, the survey gathered input on how
the city can better support disadvantaged communities by reducing environmental pollution,
identifying key community needs, and increasing the voice of marginalized groups in the City's
decision-making process. The survey findings will support the integration of environmental
justice into the City’s General Plan Safety and Community Resilience Element.
The survey was open for two weeks from August 12th, 2021 to August 26th 2021. The survey was
sent via email to 59 staff members at local organizations or agencies that work with
disadvantaged communities or focus on diversity, equity, and inclusion. The survey was also
shared with participants of the Environmental Justice Working Group.
Participation:
The survey received 7 responses from the following organizations:
• Diversity Coalition San Luis Obispo County
• SLO Food Bank
• HASLO
• United Way of San Luis Obispo County
• Lumina Alliance
• CAPSLO
• Habitat for Humanity SLO County
Populations Served:
All respondents indicated that they serve populations that live, work, and/or go to school in the City
of San Luis Obispo. All organizations reported that they serve low-income, non/limited English
speakers. Also, all organizations serve young children and youth within SLO. The majority (6/7) of
responses showed to support those who are unhoused, unemployed, and uninsured. People without
vehicle access, undocumented individuals and families, people with disabilities, and outdoor workers
are also served by a majority of organizations. About half of respondents show support for people
with chronic health conditions and people with severe mental illness.
Only one organization (Diversity Coalition SLO County) indicated that they aid racial and ethnic
people of color and faith-based communities, this same organization specifically supports BIPOC
populations. One individual organization described that they serve “low income residents of SLO
County who lack the resources to purchase or obtain enough food for themselves or their families”
while another organization noted they assist those with affordable housing ownership. One other
organization serves victims of violence particularly.
Environmental Pollutants Adversely Impacting Vulnerable Populations
Types of environmental pollutants (all listed frequently among the respondents)
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• Exhaust and traffic pollution from living in proximity to major roadways
• Contaminated drinking water
• Lead paint or pipes in housing
• Pesticide pollution from agriculture
• Living/working near environmental clean-up sites
• Smoke from wildfires
Populations are affected mostly by living and working near the environmental pollutants listed.
Farmworkers are at risk to greater pesticide exposure and are also impacted more by wildfire smoke
as they are working outdoors.
Low income housing are often based in areas that are more impacted by pollutants such as noise
and exhaust from higher traffic volumes.
Due to insufficient resources and low level priorities from local governments, vulnerable populations
are subject to substandard living conditions, lack of proper education/recognition, and are of a low
priority for remediation.
Recommendations for how the City can Help Protect Vulnerable Populations from
Environmental Pollutants, Hazards and Climate Change Impacts
• Host listening sessions inside of affected communities.
• Devote new human and material resources to investigate and remedy environmental
injustices.
• Identify and appoint leadership from within the affected communities
• Provide monetary or other basic needs support to farmworkers when their work is disrupted
by unusual or dramatic climate events
• Incorporate greater city plans to clean up pollutants and test for pollutants in soil and other
locations
• Provide access to resources, education, funding, and create platforms/events where
community members may share their experiences and be intentionally listened to
Community Improvements to Protect the Wellbeing and Safety of Vulnerable Populations
1. Better transit services (more routes, more stops, shorter wait times).
2. Low income housing.
3.
• Cooling Centers.
• Broadband access.
• Cooling/heating for homes and apartments (air conditioning/heat pumps).
4.
• Park access.
• Address food deserts by providing farmers markets and such in low income areas.
• Street Trees.
• Translation Services.
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• Safe parking/ camping areas for the unhoused population that includes services and
resources.
• Community gathering places.
“Real, tangible short and long-term, result driven solutions that are not based in politically motivated
rhetoric and empty promises”
A general consensus shows these needs are anticipated to change beside one organization which
does not think community needs will change as impacts increase. It was noted that better public
transportation and cooling centers will rise in importance. Additionally, heightened rates of
demographic change will increase need for affordable housing, educational resources, and access to
broadband.
Important Public Services and Amenities
• Access to safe living conditions, legal services, and affordable child care.
• Libraries, bus transit, bicycling paths, safe overnight parking, public bathrooms, programs
specifically targeted towards low-income housing.
• Living wage jobs and access to affordable housing.
• Access to public parks and recreation
• Transit improvements for senior and disabled populations.
Specifically for disaster situations
• Cooling centers, clean and safe shelters
• Access to food, clean water, electricity, and transportation
• Translation services and assistance for those with mobility issues
• Temporary housing for displaced individuals
Healthy Food Access
• Increase support for food banks
o Partner with SLO Food Bank to determine regional gaps in service.
o Create opportunities for food distributions, pantries, free farmer’s markets in
underserved communities.
• Improve public transportation to super markets and farmers markets
• Support food banks, farms, and gardens for low income neighbors
Participation in the Public Decision-Making Process
Barriers
• Language barriers seem to be most prevalent.
• Lack of trust also drives participation downward.
• Don’t hear about opportunities (e.g not well connected to the City communication channels)
• Seems to be inaccessible to many people:
o Too little time to engage ( when struggling to put food on table, dealing with
violence, engagement in public government not on radar.
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o Inaccessible meeting times
• Disconnection between members of the public and government body
o Topics of city meeting not relevant
o Lack of interest
o Lack of knowledge on government processes.
Recommendations for improved involvement and communications
• Ensure affected communities have opportunities to create agendas, not simply respond to
agendas.
• Incentivize participation
• Consider alternative meeting times outside of work week/hours
• Collaborate with trusted partners/agencies within different communities to spread
information (specific recommendation to use CAPSLO to disseminate info of interest to
civilians.
• “Prioritize and focus on real life, basic needs that enhance and sustain”
Additional Comments
- “Further reduce jobs/housing imbalance in order to reduce job commute times and all things
associated with them (reduced air quality, decreased quality of life etc.)
- Please sustain our work making environmental justice a core priority in the city’s service to all
its citizens, don’t allow to fall between the cracks... Thank you.
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January 2021
City of San Luis Obispo
990 Palm Street
San Luis Obispo, CA 93401
Resilient SLO:
Baseline Conditions Report
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20200048.01
Resilient SLO: Baseline Conditions Report
Prepared for:
City of San Luis Obispo
990 Palm Street
San Luis Obispo, CA 93401
Prepared by:
Ascent Environmental
455 Capitol Mall, Suite 300
Sacramento, CA 95814
Authors
Ascent: Masury Lynch, Angie Xiong, Kai Lord-Farmer,
and Honey Walters
Fehr & Peers: Marshall Ballard,
Charlie Coles, and Taylor Whitaker
cbec: Chris Bowles, Luke Tillmann,
and Michael Founds
January 2021
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Public Draft Baseline Conditions Report City of San Luis Obispo i
TABLE OF CONTENTS
Section Page
LIST OF ABBREVIATIONS .......................................................................................................................................................................... III
1 INTRODUCTION ........................................................................................................................................................................ 1-1 1.1 Resilient SLO Community Priorities Survey ........................................................................................................... 1-2
2 EXISTING HAZARDS ASSESSMENT ...................................................................................................................................... 2-5 2.1 Local and Regional Plans ........................................................................................................................................... 2-5 2.2 Planning Resources ..................................................................................................................................................... 2-7 2.3 Existing Hazards Assessment .................................................................................................................................... 2-8
3 SENSITIVE INFRASTRUCTURE, POPULATIONS, AND FUNCTIONS ............................................................................... 3-1 3.1 Transportation System and Built Environment .................................................................................................... 3-1 3.2 Socioeconomic Trends and Vulnerable Populations ........................................................................................ 3-13 3.3 Community and Economic Functions ................................................................................................................... 3-13
4 REPORT FINDINGS AND NEXT STEPS ................................................................................................................................ 4-1
5 REFERENCES ............................................................................................................................................................................... 5-1
Appendices
Appendix A - CAL FIRE Hazard Severity Zone Maps Appendix B - Resilient SLO Community Priorities Survey
Figures
Figure 1-2 Resilient SLO Planning Process .................................................................................................................................. 1-1
Figure 1-2 City Resident’s Climate Concern by Age ................................................................................................................ 1-3
Figure 2-1 Waterways and Floodplain Areas in the City of San Luis Obispo with Critical Facilities ........................ 2-10
Figure 2-2 City Resident’s Flooding Concern and Impact ................................................................................................... 2-14
Figure 2-3 City Average Annual Temperature from 1928 to 2018 (Cal Poly Weather Station) ................................. 2-15
Figure 2-4 Urban Heat Island Effect and Tree Cover in the City ........................................................................................ 2-17
Figure 2-5 City Resident’s Extreme Heat Concern and Impact .......................................................................................... 2-18
Figure 2-6 Wildfire Hazard Severity Zones In and Surrounding the City of San Luis Obispo with Critical Facilities .......................................................................................................................................................... 2-20
Figure 2-7 Wildfire Perimeters for Wildfires within 10 Miles of the City of San Luis Obispo (1900–2020) ............ 2-21
Figure 2-8 City Resident’s Wildfire and Wildfire Smoke Concern and Impact ............................................................. 2-23
Figure 3-1 Major Roadways in San Luis Obispo by Traffic Volume ................................................................................... 3-2
Figure 3-2 Existing and Proposed Bikeways ............................................................................................................................. 3-4
Figure 3-3 Pedestrian Infrastructure within San Luis Obispo ............................................................................................... 3-5
Figure 3-4 Public Transit Routes within San Luis Obispo ...................................................................................................... 3-6
Figure 3-5 Commuting Characteristics by Mode in the City and County ........................................................................ 3-7
Figure 3-6 Transportation Infrastructure and Facilities and Flood Zones ........................................................................ 3-9
Figure 3-7 Low-Income Communities as Defined under Assembly Bill 1550 ................................................................ 3-15
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Tables Table 3-1 Annual Average Daily Traffic and Level of Service of Highway Segments in San Luis Obispo ............. 3-1
Table 3-2 Critical Facilities and Infrastructure in the City of San Luis Obispo .............................................................. 3-10
Table 3-3 Critical Facilities Located in 100-Year and 500-Year Flood Zones ................................................................ 3-12
Table 3-4 Critical Facilities Located in Very High or High Fire Hazard Severity Zones ............................................. 3-12
Table 3-3 City Demographics by Sex, Race, and Age ......................................................................................................... 3-13
Table 3-4 Housing Cost Characteristics ................................................................................................................................... 3-14
Table 3-5 Gross Rent as a Percentage of Monthly Household Income ......................................................................... 3-14
Table 3-6 Health Insurance Coverage ...................................................................................................................................... 3-17
Table 3-7 Languages Spoken by City Residents ................................................................................................................... 3-17
Table 3-8 Employment by Economic Sector in the City of San Luis Obispo for 2018 ............................................... 3-15
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LIST OF ABBREVIATIONS
°F Fahrenheit
CALFIRE Department of Forestry and Fire Protection
Cal Poly California Polytechnic State University at San Luis Obispo
CDC Center for Disease Control and Prevention
COVID-19 2019 coronavirus disease
County County of San Luis Obispo
City City of San Luis Obispo
FEMA Federal Emergency Management Agency
GHG greenhouse gas
GIS geographic information system
HASLO Housing Authority of San Luis Obispo
HMP San Luis Obispo County Multi-Jurisdictional Hazard Mitigation Plan
HPI California Healthy Places Index
IPCC Intergovernmental Panel on Climate Change
Report Baseline Conditions Report
RTA San Luis Obispo Regional Transit Authority
SR State Route
USACE US Army Corps of Engineers
UWMP Urban Water Management Plan
WUI wildland-urban interface
WRRF Water Resource Recovery Facility
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1 INTRODUCTION
This Baseline Conditions Report (Report) has been developed as part of Resilient SLO, a planning process undertaken by the City of San Luis Obispo (City) to better understand the local impacts of climate change and incorporate climate adaptation and resilience strategies into the City’s General Plan Safety Element, consistent with requirements
in Senate Bill 379. Senate Bill 379 requires communities in California to incorporate strategies to mitigate the impacts of climate change in their general plan safety element and plays an important role in helping the City become more resilient to the current and future effects of climate change. Resilience refers to the capacity of individuals,
communities, institutions, businesses, and systems to survive, adapt, and thrive in the face of chronic stresses and acute shocks (APA 2017). The Report has been developed to understand the City’s current climate-related hazards and provide a baseline for key characteristics of the community that are likely to be affected by climate change. The Report serves as the first step in the development of the City’s comprehensive climate change vulnerability assessment and provides a historical frame of reference to understand how climate change will affect the City. Figure 1-1 illustrates the four main steps of the Resilient SLO planning process. This report serves as the culmination of work complete in Step 1 of the process.
Figure 1-2 Resilient SLO Planning Process
The City has adopted its Climate Action Plan for Community Recovery, which focuses on reducing greenhouse gas (GHG) emissions produced from community activities. The plan sets an ambitious target of carbon neutrality by 2035,
adopts sector-specific goals, and identifies concrete actions to chart a path toward achieving those goals. The City’s efforts are consistent with other jurisdictions that are demonstrating leadership in reducing GHG emissions and sharing successes and lessons learned with other communities in support of widespread climate action at the speed and scale
required to stabilize the increase in global temperature caused by climate change at or below 2 Celsius (C)2C.
While the City continues to reduce local emissions, it is important to recognize that warming due to anthropogenic activities from the pre-industrial period to the present will persist for centuries to millennia and continue to cause further long-term changes in the climate system. As stated by the Intergovernmental Panel on Climate Change (IPCC), human activities that generate GHG emissions are estimated to have caused approximately 1.0°C of global warming above pre-industrial levels with increases likely reaching 1.5°C (2.7 between 2030 and 2052) if emissions continue to increase at the current rate (IPCC 2018). Trends, beginning in the 1950s, in the intensity and frequency of
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climate and weather extremes have been detected when only 0.5°C of global warming occurred. These weather extremes including long-term drought, extreme heat events, increased wildfire risk, and extreme storm events are anticipated to increase in intensity and frequency as the average global temperature increases to between 1.5 and
2°C. Due to past and ongoing emissions at their current rate, estimated anthropogenic global warming is projected to increase at a rate of 0.2°C (likely between 0.1°C and 0.3°C) per decade due to past and ongoing emissions (IPCC 2018). As a result, the City must begin to prepare for the impacts of climate change, despite future trends in local and
global GHG emissions.
Because climate impacts and their severity will vary throughout the state, local resilience and adaptation planning focuses on understanding the anticipated regional and local climate impacts. The first step in this process is to assess existing hazards and sensitivities that may be affected by climate change. This Report focuses on identifying the City’s historic and current exposure to climate-related hazards, as well as determining community assets (i.e., infrastructure,
functions, and populations) that are likely to be affected. The document is organized into two sections:
Existing Hazards Assessment—This section summarizes local and regional plans and resources and evaluates existing hazards that may be exacerbated by climate change. In the City, these climate hazards include flooding, extreme heat, and wildfire, as well as their secondary effects. This section also includes a brief discussion of the current COVID-19
pandemic. The existing climate hazards described in this section serve as a baseline against which to assess future climate conditions and the magnitude of changes that are projected to occur through the 21st century.
Sensitive Infrastructure, Populations, and Community Functions—This section discusses the City’s transportation system, critical facilities and infrastructure, socioeconomic trends and vulnerable populations, and community and economic functions that could be affected by climate change. To help explain how climate change may
affect the City in the future, this section also describes how the City’s community assets have been affected by climate-related hazards in the past. In addition, this section identifies specific populations in the City that are disproportionately affected by existing hazards and may be disproportionately affected by future climate hazards.
1.1 RESILIENT SLO COMMUNITY PRIORITIES SURVEY
As part of the development of this report, a community priorities survey was developed to gather input on overall community priorities regarding climate-related hazards, concerns related to climate change impacts, experience with past hazard events and response efforts, and priorities for local action. The survey, consisting of 19 questions, was
open from August 31, 2020 – October 11, 2020 and had 328 responses. The survey results will be used to inform the vulnerability assessment and hazards report, as the next step in the Resilient SLO planning process, as well as the future community engagement and education activities. Highlights from the survey results have been included in this
Report to help better understand the community’s priorities regarding climate-related hazards.
As part of the survey, participants were asked what climate-related impact they were most concerned about. Figure 1-2 illustrates the responses to this question by age group. As shown in Figure 1-2, respondents were most concerned about wildfires and associated poor air quality events. Leading up to and during the survey response period, the City experienced poor air quality from several wildfires in the surrounding region, which may have influenced survey results. The large majority of respondents were also concerned about drought, increasing temperatures, and heat wave events and much less concerned about flooding and sea level rise. Survey results for this question also highlight
that respondents in the 18-24 year old age cohort were the most concerned about almost all climate issues. To explore the full results of the community priorities survey, please refer to Appendix A of this report.
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Sources: Resilient SLO Community Priorities Survey
Figure 1-2 City Resident’s Climate Concern by Age
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Drought and
Decreased
Water Supply
Flooding and
Storm Damage
Hotter
Temperatures
and Heat
Waves
Sea Level Rise Wildfires Wildfire SmokePerecnt of RespondentsClimate Impact
CLIMATE CONCERN BY AGE
18-24
25-34
35-44
45-54
55-64
Above 65
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2 EXISTING HAZARDS ASSESSMENT
This section provides an overview of local and regional plans, as well as a summary of existing hazards in the City that are anticipated to be affected by climate change. Plans and resources reviewed are the City’s annex to the San Luis Obispo County Multi-Jurisdictional Hazard Mitigation Plan (HMP) (San Luis Obispo County 2019a), the current
General Plan Safety Element (City of San Luis Obispo 2014), the California Governor’s Office of Emergency Services’ MyHazards mapping tool, Cal-Adapt, the California Heat Assessment Tool, the California Healthy Places Index (HPI), and geographic information system (GIS) data from the California Department of Transportation GIS Open Data and
the City and County of San Luis Obispo Open Data Repository.
This section also includes background information on the overall climate and topography in the region and includes a detailed discussion of three existing hazards that may be exacerbated by climate change: flooding, extreme heat, long-term drought, and wildfire. Statistics and figures are provided to illustrate the extent of past impacts and geographic areas at risk for each hazard.
2.1 LOCAL AND REGIONAL PLANS
This section provides a general summary of local and regional plans related to existing hazards and describes how they can support increasing the City’s resilience to the current and future impacts of climate change. The plans discussed in this section were used to develop this Report and help establish a planning framework to be used during
various stages of the Resilient SLO development process.
2.1.1 San Luis Obispo County Multi-Jurisdictional Hazard Mitigation Plan
The HMP assesses all current human-made and natural hazards in San Luis Obispo County (County) and the incorporated cities in the County, including the City of San Luis Obispo. It also provides practical and cost-effective mitigation solutions to reduce the County’s vulnerability to hazards and reduce both human and financial losses from
hazardous events (San Luis Obispo County 2019a). The HMP, which was last updated in October 2019, includes community profiles for the incorporated cities, community services districts, and special districts in the County. The HMP and City specific Annex G acknowledges the role climate change will play in exacerbating future hazards and recognizes the importance of preparing climate-specific hazard mitigation strategies. Climate change considerations are discussed for each hazard. The following hazards discussed in the HMP specifically relate to climate change:
adverse weather (e.g., thunderstorms, high winds, extreme heat);
agricultural pest infestation, plant disease (e.g., tree mortality), and invasive species;
naturally occurring biological agents (e.g., vector borne diseases);
coastal storms, erosion, and sea level rise;
dam failure;
drought and water shortage;
flooding;
landslides and debris flow;
soil hazards and land subsidence; and
wildfires.
Annex G of the HMP (San Luis Obispo County 2019b),a community profile specific to the City, supersedes the City’s previous Local Hazard Mitigation Plan (LHMP), which was first published in 2006 with an update in 2014. Annex G
provides an in-depth discussion of the City’s climate, economy, and demographics and presents an assessment of the City’s vulnerability to natural and human-made hazards. Annex G also includes a capability assessment that provides an inventory of existing regulatory tools (e.g., ordinances, plans), personnel resources, financial resources (e.g., grants,
fees), and partnerships that are currently used or could be used in the future to implement hazard mitigation activities. A mitigation action plan was developed, based on the capability assessment, and identifies mitigation
strategies for each of the hazards discussed in the HMP.
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Annex G of the HMP includes a detailed description of the planning process used to produce the plan, background information about the City, a hazard risk assessment, a capability assessment, mitigation strategies, and an implementation and monitoring plan. Annex G of the HMP also includes the following goal specific to preparing for
climate impacts in the City. The Resilient SLO planning process supports objectives 3.A and 3.B.
GOAL 3: Prepare for and adapt to the impacts of climate change.
Objective 3.A: Use, and update as needed, the best available science to estimate exposure, vulnerability, and risk of hazards as the result of climate change.
Objective 3.B: Use the climate change exposure, vulnerability, and risk assessments to ensure mitigation
investments, capital projects, and programs actively mitigate climate impacts.
2.1.2 City of San Luis Obispo General Plan Safety Element
The City’s current General Plan Safety Element (City of San Luis Obispo 2014), which was adopted in 2000 and last
revised in 2014, identifies goals and policies to avoid or minimize the loss of life, property, and prosperity that can result from disasters and to help the City and its residents recover quickly from unavoidable disaster events. The
Safety Element identifies the level of risk for various hazards by evaluating the probability of loss, the City’s capacity to reduce risks, the potential severity of loss, and the adequacy of knowledge about the hazard.
Hazards discussed in the Safety Element include flooding, fire, earthquakes and geologic hazards, hazardous materials, electromagnetic fields, airport hazards, and hazardous trees. The Safety Element also identifies programs and policies to aid the City in avoiding and preparing for emergencies, such as investing in City staff training,
implementing the Standardized Emergency Management System, engaging citizens in preparedness education, and maintaining an Emergency Operations Center Plan. Although the City’s current Safety Element does discuss climate-related hazards (e.g., wildfire, flooding), it does not include a discussion of climate change or assess how various hazards will be affected or exacerbated by climate change.
2.1.3 Urban Water Management Plan
In 2015, the City adopted the Urban Water Management Plan (UWMP) which evaluates the City’s current and projected water supplies through the year 2035. The UWMP was prepared in accordance with the Urban Water
Management Planning Act (Act), and; accordingly, will be updated every 5 years and submitted to the California Department of Water Resources. Goals in the UWMP related to this this Report include the following:
assess current and future water use trends in the community;
summarize the water supply and the water system;
assess water supply reliability;
document the water demand;
manage measures in place to balance supply and demand; and
demonstrate compliance with SB X7-7 which requires the City to develop urban water use targets to help meet the goal of a 20 percent reduction goal by 2020.
2.1.4 Waterway Management Plan
In 2003, the City developed and adopted its current Waterway Management Plan in coordination with the San Luis Obispo County Flood Control and Water Conservation District Zone 9 Advisory Committee. The purpose of this plan
is to adopt an approach and schematic plans to address flooding, erosion, water quality, and ecological issues in the San Luis Obispo Creek Watershed that can be implemented with approval from various regulatory agencies.
The plan includes five key components to achieve the plan’s objective. These include the following:
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Stream Maintenance and Management Program and guidance document for routine stream maintenance;
new Drainage Design Manual for storm water, flood control, and bank repair design;
Flood Management Plan that outlines the conceptual flood control alternatives;
Bank Stabilization Program that provides a management framework and conceptual plans for addressing current and future bank instability problem areas; and
Habitat Enhancement and Restoration Program that provides a conceptual plan and framework for stream resource enhancement, restoration, and protection.
2.1.5 Community Wildfire Protection Plan
The City of San Luis Obispo adopted the Community Wildfire Protection Plan (CWPP) in 2019. The purpose of the CWPP is to collaboratively address fire protection planning efforts occurring in the City, minimizing wildfire risk to
watershed lands, assets, firefighters, and the public. The CWPP includes the following:
the City’s physical and social characteristics,
wildfire history and landscape-scale fire hazard variables in the City,
an evaluation of wildfire risk in priority areas, and
strategies for reducing structural ignitability, conducting public education and outreach; and, reducing fuel loads,
and minimizing wildfire risk in the community.
2.2 PLANNING RESOURCES
This section includes a brief summary of resources available to the public that will be used in the vulnerability assessment, some of which were used in this Report to identify baseline conditions for the assessment of future climate-related risk.
2.2.1 California Governor’s Office of Emergency Services MyHazards
Mapping Tool
The California Governor’s Office of Emergency Services MyHazards mapping tool is an interactive map that displays information about earthquake, liquefaction, tsunami, flood, and fire hazards throughout the state. MyHazards also provides general information about each hazard and links to other resources for more detail about specific hazards
and preparedness measures.
2.2.2 California Adaptation Planning Guide
In August 2020, the Governor’s Office of Emergency Services completed an update to the California Adaptation Planning Guide (APG) (Cal OES, 2020). The California Adaptation Planning Guide (APG) is designed to support local government, regional organizations, and climate collaborative groups to integrate best practices and current science
into their adaptation planning efforts. Guidance from the APG was used to develop this report and will be used as one of the primary guidance documents during the Resilient SLO planning process.
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2.2.3 Federal Highway Administration’s Vulnerability Assessment
and Adaptation Framework
The Federal Highway Administration’s (FHWA’s) Vulnerability Assessment and Adaptation Framework is a guidance
document developed to support transportation agencies and their partners assess the vulnerability of their transportation systems to extreme weather and the impacts of climate change. The document also helps agencies integrate climate adaptation considerations into transportation decision-making and provides an in-depth process for
conducting a vulnerability assessment. Relevant sections of this document were used to develop this report and will be used as one of the primary guidance documents during the Resilient SLO planning process.
2.2.4 Cal-Adapt
Cal-Adapt is a tool developed by the University of California, Berkeley’s Geospatial Innovation Facility, California Energy Commission, and California Strategic Growth Council that uses global climate simulation model data to
provide a view of how climate change might affect California. Climate datasets on Cal-Adapt include historical observations, as well as downscaled climate projections, which are used to create charts and maps that display
climate variables through time. Cal-Adapt includes climate variables, such as temperature, precipitation, sea level rise, snowpack, wildfire, streamflow, and drought.
2.2.5 California Heat Assessment Tool
The California Heat Assessment Tool is a tool developed by the California Natural Resources Agency as part of the state’s Fourth Climate Change Assessment. The tool provides information for local and state health practitioners to
better understand dimensions of heat vulnerability driven by climate changes and where action can be taken to mitigate the public health effects of extreme heat in the future.
2.2.6 CalEnviroScreen
CalEnviroScreen, a web-based tool developed by the California Office of Environmental Health Hazard Assessment (OEHHA), uses a science-based method for evaluating multiple pollution sources in a community while accounting
for local vulnerabilities. The purpose of the tool is to identify which communities are most burdened by pollution from multiple sources and which are most vulnerable to its effects, taking into account the socioeconomic and health
status of people living in those communities. The tool provides a set of indicator data that will help to identify portions of the City particularly vulnerable to climate-related hazards.
2.2.7 California Healthy Places Index
The California HPI, developed by the Public Health Alliance of Southern California, provides an interactive map, graphs, data tables, and a policy guide to examine local health factors and compare local conditions to those across
the state. Climate health vulnerability indicators are built into the HPI by incorporating climate-related hazards data layers into the mapping (e.g., air conditioning access, public transit access); incorporating select climate-resiliency
metrics into the HPI score, which combines 25 community characteristics into a single indexed score to describe a community’s overall health; and addressing climate challenges in the policy guide.
2.3 EXISTING HAZARDS ASSESSMENT
This section provides an overview of existing climate-related hazards in the community and serves as a comparative baseline for assessing future climate conditions and the magnitude of changes that are projected to occur through
the 21st century.
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2.3.1 Geography and Climate
The City is located west of the Santa Lucia Mountains and 8 miles east of the Pacific Ocean in the Central Coast region of California. It occupies approximately 10.7 square miles and is surrounded primarily by protected open space and
agriculture. Although the City itself is on average 300 feet above sea level, much of the terrain surrounding the City is mountainous, with prominent peaks such as Cerro San Luis and Bishop Peak at 1,292 and 1,559-feet above sea level, respectively (San Luis Obispo County 2019b).
San Luis Obispo experiences a Mediterranean climate, which is characterized by dry summers and mild, wet winters. Although this is the general trend, the region has historically experienced both unseasonably warm and cold periods. The City has an annual average temperature of 70.2 degrees Fahrenheit (°F) and average precipitation of 19 inches per year, occurring primarily in the winter and spring months. The City’s climate is influenced by the proximity of the ocean, resulting in weather events including dense fog, offshore wind, and coastal storms (San Luis Obispo County 2019b).
2.3.2 Flooding
This section provides a summary of the San Luis Obispo Creek watershed and describes existing flooding issues in the City and the surrounding region. Two interchangeable, technical terms that characterize flood frequency are used
throughout the section and are defined as follows:
Recurrence Intervals: A common way to describe floods is by stating their recurrence intervals, which refer to how often, on average, a given flood may occur. A 100-year event, for example, is described as an event that may occur about once in every 100 years, on average. However, this terminology can be misleading because flood events are statistical occurrences, and events may occur more frequently than their recurrence interval suggests.
Exceedance Probability: The exceedance probability of a given flood event is the percent chance that a larger flood will occur in any given year, and it is calculated by dividing the number 1 by the recurrence interval. Thus, the “100-year event” becomes the “1-percent exceedance event,” or a flow rate that has a 1-percent chance in any given year of being equaled or surpassed by a larger flow rate. This representation, although interchangeable with the recurrence interval, provides a more helpful way to think about flood risk.
There are several overall mechanisms by which flooding can occur:
dam inundation flooding, in which impounded water is released because of dam breaching;
localized flooding, which occurs when intense rainfall overwhelms the capacity of local drainage infrastructure, causing the ponding of water; and
riverine flooding, which occurs when channels (i.e., the relatively deep, narrow sections of creeks and rivers) cannot contain the flow volume moving through them, causing water to spill out into the overbank areas (i.e., the relatively wide, flat regions on one or both sides of the channel, also called “floodplains”).
According to the HMP, the City is not at risk of dam inundation flooding, and localized flooding is considered a minimal risk. The highest flooding concern for the City is riverine flooding, which may include “flash” flood risks (San
Luis Obispo County 2019b).
SAN LUIS OBISPO CREEK WATERSHED
As shown in Figure 2-1, San Luis Obispo Creek flows through the City in a northeast to southwest direction, passing through the downtown area and generally following U.S. Highway (U.S.) 101 on its way to the Pacific Ocean at Avila Beach. The watershed for San Luis Obispo Creek, the land area that captures rainfall and contributes water directly to
the creek system, covers an area of approximately 84 square miles, ranging in elevation from approximately 2,460 feet in the upper watershed near the Cuesta Grade to its outlet into the Pacific Ocean. Along its main flow path, it transitions from steep canyons to the gently sloping alluvial plain underlying the City, descending more than 2,230 feet to downtown. In the City’s downtown, San Luis Obispo Creek flows through the “under-city culvert,” consisting of a system of covered, constructed channels between Osos Street and Chorro Street that is more than 1,000 feet long and 18–23 feet wide (Questa Engineering Corporation 2003, 2015), before emerging into Mission Plaza.
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020 and processed by cbec eco engineering in 2020.
Figure 2-1 Waterways and Floodplain Areas in the City of San Luis Obispo with Critical Facilities
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Further downstream, near the intersection of Marsh Street and Higuera Street, San Luis Obispo Creek is joined by a major tributary, Stenner Creek, which in turn receives flow from Brizzolara and Old Garden Creeks. San Luis Obispo Creek then continues south along the alluvial plain, intercepting Prefumo Creek as it exits Laguna Lake and joining
East Fork San Luis Obispo Creek near the Higuera Street/U.S. 101 interchange by the Johnson Ranch Open Space. Near the confluence of San Luis Obispo Creek with Davenport Creek, the channel enters “the Narrows” (Questa Engineering Corporation 2003), passing through a steep, confined canyon before being joined by See Canyon Creek
and discharging to the Pacific Ocean. Flows in the watershed are “flashy,” meaning that water moves quickly through the system and that stream levels rise and recede rapidly in response to rainfall events. This is a result of the steep topography of the upper watershed and the relatively shallow soils, land cover, and rainfall characteristics for the region (Questa Engineering Corporation 2003).
HISTORICAL FLOODING
The San Luis Obispo Creek watershed has a long history of flooding, with a series of storms over the last 50 years that
have caused millions of dollars’ worth of damage.1 Damaging flood events have occurred in 1868–1872, 1884, 1897, 1911, 1948, 1952, 1962, 1969, 1973, 1995, 1998, and 2001 (Questa Engineering Corporation 2003; City of San Luis Obispo 2014). The flooding events in January and March 1995 occurred during one of the wettest periods on record, causing
the watershed to be relatively saturated for long periods, which prevented soils from absorbing incoming precipitation. The 1995 flooding events followed the 1994 Highway 41 fire, which burned major areas of the Stenner Creek and upper San Luis Obispo Creek watersheds and caused increased runoff and sediment delivery to channels. Flow spilled out of the San Luis Obispo Creek channel in the region around Marsh and Higuera Streets, causing extensive damage, and remained out of the creek banks for nearly 3 miles downstream. The events, for which the peak flow was estimated to be the 17-year flood event 2 (6-percent exceedance probability), caused $2.3 million in damage (Questa Engineering Corporation 2003). Prior events were even more damaging: The 1969 flood caused
$6.92 million in damage, and the 1973 flood caused $13.6 million in damage. During the 1973 flood, depths of inundation over U.S. 101 exceeded 4 feet near the Madonna Inn and were up to 3 feet near the Prefumo Creek
confluence (Questa Engineering Corporation 2003).
FLOOD RISK
Following the 1973 flood, watershed studies and plans were developed and updated, including the 1974 U.S. Army Corps of Engineers floodplain study of San Luis Obispo Creek (USACE 1974), 1977 Nolte & Associates study (George S.
Nolte & Associates 1977), and 1978 Federal Emergency Management Agency (FEMA) flood insurance study. The extent of 100-yr and 500-yr flood zones, based on these studies, is shown in Figure 2-1.
In 2003, the City’s WMP was completed, which relied on updated analyses for flow frequency. In general, the flow estimates provided by the WMP for a given recurrence interval are higher than those reported in the prior studies, leading to the recommendation that the WMP be used for design considerations for projects in the City, as a
conservative assumption, as well as the adoption of the updated flow frequency estimates by the City. However, the FEMA inundation extents, shown in Figure 2-1, were generally validated by the 2003 WMP for the 100-year event despite the slightly higher depths reported by the WMP (Questa Engineering Corporation 2003). The FEMA inundation extents further indicate the 500-year flood hazard area, which was not assessed as part of the WMP, and they are still provided on the City’s website and serve as an important reference. According to the WMP, nearly all
streams in the San Luis Obispo Creek watershed have less than a 25-year (4-percent exceedance probability) flood capacity, with some experiencing flooding in the 10- to 15-year range (Questa Engineering Corporation 2003).
1 Storm damages were normalized to reflect costs in the year 2000.
2 According to the flood frequency analysis conducted for the 2003 Waterway Management Plan (Questa Engineering Corporation 2003), which represent updated flood frequency information compared to the Federal Emergency Management Agency study (1978).
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Flood Risk Factors For the San Luis Obispo Creek watershed, factors that may directly contribute to flooding are infrastructure-induced
flow constrictions, wildfire, and degraded riparian corridors (Questa Engineering Corporation 2003). In terms of flooding from infrastructure, bridges often serve as flow constrictions because the abutments, or structures
connecting the bridge deck to the ground, may occupy part of the floodplain for a channel in order to reduce the span width of the deck. In addition, bridge piers can intercept transported debris, particularly woody vegetation, and reduce conveyance through the structure. The U.S. 101 and Santa Rosa Street bridges over Stenner Creek were
upgraded following the highly damaging 1973 flood to prevent these occurrences and reduce future flood risk (Questa Engineering Corporation 2003). The Marsh Street Bridge in the City’s downtown, first built in 1909, is currently being replaced and is scheduled to be completed in January 2021. One of the greatest flow constrictions in the watershed is the undercity culvert. The capacity of the culvert was estimated in the 1977 publication Flood Control and Drainage Master Plan for the San Luis Obispo Creek Watershed (George S. Nolte & Associates 1977) at 4,500 cubic feet per second. This flow rate is below the 25-year event (4-percent exceedance probability) according to FEMA flood insurance studies (FEMA 1978), indicating that the culvert is unable to manage water flow during the 25-year
flood event. The 2003 WMP, which provided updated estimates for flood frequency, estimated the capacity of the culvert to be close to the 15-year event (7-percent exceedance probability), Questa Engineering Corporation 2003). Flows exceeding the undercity culvert capacity may exit the channel at Osos Street or further upstream at the Santa Rosa or Marsh Street bridges and cause overland flooding within downtown, particularly along the Marsh Street corridor and areas surrounding the creek channel.
Post-wildfire runoff represents another risk for flooding because burned areas in the watershed will contribute more runoff and higher sediment loads than vegetated areas. As previously mentioned, the 1995 floods, which caused
approximately $2.3 million in damages, followed the 1994 Highway 41 fire and the loss of vegetation on hillslopes contributed to high runoff volumes. Overall, about one third of the San Luis Obispo Creek watershed is considered by the California Department of Forestry and Fire Protection (CAL FIRE) to be in Very High Fire Hazard Severity Zones, based on
an analysis of publicly available GIS data (CAL FIRE 2020). Wildfire impacts are further discussed in Section 2.2.4.
Finally, degradation of riparian corridors, the thin strips of trees and other vegetation lining the creeks, may contribute to flooding within the San Luis Obispo Creek watershed. Historically, riparian zones would have been composed of tall, single-trunk sycamores, cottonwoods, and willows, but these areas are now characterized by shrubby willow growth (Questa Engineering Corporation 2003). This results in more low-hanging branches coming
into contact with flowing water, which increases the roughness of the creek channels and consequently reduces flow velocities. When the water is slowed, water levels in the channel are increased and overflow into surrounding lands
becomes more likely.
Urbanization, the conversion of land to impervious surfaces as a result of urban development, has indirectly affected flood risk by altering the shape and function of the creek channels within the watershed. Overall, the San Luis Obispo Creek watershed is about 10 percent urbanized, meaning that 10 percent of the land area within the basin 3 that drains
to the outlet of San Luis Obispo Creek at Avila Beach is covered by urban development. However, when considering only the portion of the watershed upstream of Los Osos Valley Road, the drainage basin is 15 percent urbanized (Questa Engineering Corporation 2003). Conversion to impervious surfaces accompanying urban development results
in higher runoff rates because rainfall cannot be absorbed by the underlying soil from these surfaces. This causes water to enter the creek channels more quickly and leads to higher flow volumes and faster channel velocities on a more frequent basis. However, this effect may be reduced for increasingly large flood events. For periods of sustained, heavy rainfall, the watershed soils may be highly saturated at the time of peak rainfall and the watershed may; therefore, have a limited ability to absorb the incoming precipitation, even if the impervious surfaces had not been in place. The WMP concluded that while urban development since the 1960s has not had a large effect on increasing runoff volumes for large events (increases of less than 2 percent for the 100-yr/1-percent exceedance probability flood), notable increases
in runoff for more frequent events were determined. Specifically, flows associated with the 2-yr (50 percent exceedance probability) event were shown to increase by up to 10-12 percent in the Mid-Higuera area as a result of urbanization trends from the 1960’s to the early 2000’s. Impacts from additional urbanization of the San Luis Obispo Creek
3 Basin, or drainage basin, is another term for watershed.
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watershed will need to be determined, as a result of build-out according to the general plans for the City, County, and the California Polytechnic State University at San Luis Obispo (Cal Poly). The County is currently progressing an update to the hydrologic study of East Fork San Luis Obispo Creek to further understand flood risk in key locations and
impacts of urbanization on that region of the San Luis Obispo Creek watershed.
Although urban development from the 1960s to early 2000’s has not had a large effect on directly increasing runoff volumes from large events (e.g., 100-year/1-percent exceedance probability) in the San Luis Obispo Creek watershed,
it has greatly affected incision, or the deepening of channels through erosion (Questa Engineering Corporation 2003). The San Luis Obispo Creek watershed is vulnerable to erosion because the underlying Franciscan Complex is extensively fractured through tectonic forces and includes highly erodible layers (Questa Engineering Corporation 2003). Over time, incision can lead to a suite of flooding problems by altering the form and function of channels. Incision often results in the disconnection of creeks and rivers from their natural floodplains, as the channel cuts
deeper and more narrowly into the land surface. This tends to increase flood risk downstream as the pulse of water moving through the basin following a rainfall event is concentrated in channels and accelerated, instead of flowing
more slowly and shallowly over larger areas of land. As a result, the storage capacity of the watershed is minimized. Further, incision can lead to bank failure, in which the sloped sides of the channel become undercut by erosion related to frequent, fast-moving water and collapse inward, introducing large quantities of sediment and vegetation into the channel. This can in turn reduce flow capacity as the debris blocks portions of the channel, thereby causing localized flooding as water spills out of the channel and into surrounding areas. In some areas of the watershed,
incision has been on the order of 6–10 feet, meaning that the channel bottoms are 6–10 feet lower than they have been historically (Questa Engineering Corporation 2003). So, while urbanization since the 1960s had not been shown by the WMP to greatly increase runoff volumes for large events, the effects of channel incision over long periods of
time can still result in complex flood behavior that may ultimately worsen flooding from large storm events regardless of whether or not the runoff, and therefore the flow within the channel, is increasing markedly.
In addition to urbanization, there are several other causes of this widespread incision problem. The historic presence of small dams in the upper watershed (near Stagecoach Road, which has been removed, and the larger Reservoir Canyon facility) prevented large sediments (cobble and large gravels) from being transported downstream. Naturally, these eroded sediments would have continuously filled in the channels, but instead they became trapped behind the dams and filled in the small reservoirs. The creek channels continued to erode the underlying material, and with
reduced incoming sediment to offset this erosion, the channels cut deeper into the landscape. While no longer occurring at historical levels, intensive livestock grazing in the late 1800’s and early 1900’s is a legacy factor that continues to affect incision (Questa Engineering Corporation 2003). As sheep, cattle, and other hooved animals walk across a landscape, their hooves can compress the soil and reduce its ability to absorb incoming precipitation, especially if grazing in high densities. Reduction in vegetation associated with grazing can also increase runoff rates
as incoming precipitation encounters the land surface more quickly and directly. In the upper San Luis Obispo Creek watershed, intensive turn-of-20th century grazing has permanently increased runoff rates, which can subsequently drive channel incision by increasing flow rates for frequent (e.g., 2-yr) events. Further, changes to the creek channels themselves, from reducing the amount of mature vegetation along the creeks to straightening and relocating the
channels for road construction, have caused water to move more quickly into and through the channel, increasing the erosive strength of the creeks and contributing to incision (Questa Engineering Corporation 2003).
FLOOD MANAGEMENT
Flood management continues to be a high priority for the City, but there are several important barriers that can make management more difficult. First, much of the creek corridor that runs through the City along San Luis Obispo Creek and its tributaries is not owned by the City. Although the City has some authority under the City’s Municipal Code for
emergency removal of vegetation and other debris, general maintenance of the creeks falls upon the owners of property adjacent to the creek (City of San Luis Obispo 2015). Additionally, the creek corridor is highly confined in areas, particularly through downtown, making projects such as channel widening infeasible. Following the 1973 flood, the George S. Nolte & Associates study, completed in 1977, identified proposed flood control projects, but few were adopted because of the environmental effects associated with channel widening and other alternatives (Questa
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Engineering Corporation 2003). Several areas of the City, including downtown areas along San Luis Obispo Creek, the intersection of U.S. 101 and Los Osos Valley Road, the Johnson Avenue railroad underpass, and areas surrounding Laguna Lake, have been at a high risk for frequent flooding (City of San Luis Obispo 2011). To address these issues,
large projects have been proposed to manage flood risk in the increasingly urbanized City. One such proposed project is the Mid-Higuera Bypass Project, which would increase conveyance capacity of San Luis Obispo Creek between Marsh Street and Madonna Road. This area, downstream of the confluence of Stenner and San Luis Obispo
Creeks, has flooded and received extensive damage in some of the historical floods previously mentioned. The planned removal of sediment and Arundo stands from San Luis Obispo Creek south of Los Osos Valley Road will also serve to reduce local flood risk.
COMMUNITY FLOODING CONCERNS
As part of the community priorities survey, when participants were asked to report on their level of concern for flooding, as shown in Figure 2-2, 70 percent of respondents indicated that they were “Somewhat” or “Very
Concerned” about the issue. When asked about whether they had been impacted by flooding in the last 1-3 years, only 15 percent of respondents indicated “Somewhat” or “Very”. Additionally, individuals with a household income of less than $50,000 and individuals aged 18 to 24 reported the highest level of concern for flooding. Individuals who
identify as all other races and ethnicities, compared to individuals who identify as white or caucasian, also expressed a higher level of concern for flooding (i.e., 36 percent v. 24 percent, respectively).
Sources: Resilient SLO Community Priorities Survey
Figure 2-2 City Resident’s Flooding Concern and Impact
2.3.3 Average Temperatures, Extreme Heat, and Drought
The City is characterized by a Mediterranean climate. While the City is generally considered to have a mild climate, weather patterns and events have historically observed both unseasonably warm periods and cold spells. According to Cal-Adapt, during the historic period (1961–1990), the annual average maximum temperature in the City was 71.1°F and
the annual average minimum temperature was 43.7°F (CEC 2019a). Although the City has not historically experienced many extreme heat conditions, the City could be experience increased sensitivity to extreme temperatures because residents are not acclimatized to or prepared for extreme heat conditions. Extreme heat events are described in this section in terms of their intensity (i.e., average maximum temperature), frequency (i.e., how often they occur), time of year in which they occur, and duration (total number of consecutive extreme heat days). Figure 2-3 includes the average
annual maximum and minimum temperatures for the City from 1926 through 2018.
31%
44%
26%
85%
13%2%
0%
20%
40%
60%
80%
100%
Not at all Somewhat VeryPercent of RespondentsLevel of Concern
FLOODING CONCERN & IMPACT
Which of the following climate change impacts are you concerned about [Flooding]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Flooding]?
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Sources: Cal Poly 2020
Figure 2-3 City Average Annual Temperature from 1928 to 2018 (Cal Poly Weather Station)
EXTREME HEAT DAYS AND WARM NIGHTS
Cal-Adapt defines an extreme heat day as a day in a year when the daily maximum temperature exceeds the 98th historical percentile of daily maximum/minimum temperatures based on observed historical data from 1961–1990
between April and October. Based on the parameters set in Cal-Adapt, an extreme heat day for the City is defined as a day with a maximum temperature of 89.6°F or above. An average of 4 extreme heat days per year occurred in the City during the historic period (1961–1990). Heat days have historically occurred between April and late October (CEC 2019b).
Cal-Adapt defines a warm night as a night when the daily minimum temperature is above the extreme heat threshold of 57.1°F, which is the 98th historical percentile of daily minimum temperatures in the historic period (1961–1990) between April and October. In the historic period (1961–1990), an average of four warm nights per year occurred in the City (CEC 2019b). Notably, in the summer of 2020, the City experienced several prolonged extreme heat periods. In August 2020, the daily maximum temperature, recorded at San Luis Obispo Airport, was above 90°F for seven
consecutive days between August 14 and August 20, 2020, breaking several maximum daily temperature records during this period (NOAA 2020).
HEAT WAVE EVENTS
Cal-Adapt defines a heat wave as four or more consecutive extreme heat days. During the historic period (1961–1990), the maximum number of consecutive extreme heat days in the City was 2.6 days, which does not qualify as a heat wave event according to the Cal-Adapt definition. These partial heat wave events (2.6 days) have been infrequent in
the City, with an average of 0.2 event per year during the historic period (1961–1990). Because prolonged heat events have been rare in the City, both the City’s 2006 LHMP and the more recent Annex G of the County’s HMP do not discuss or evaluate extreme heat events in depth. However, maximum daily temperature records continue to be exceeded with several heat waves events occurring in the City in recent years. Because extreme heat events have not been an issue historically for the City, this may make the City particularly vulnerable and unprepared when these
events do occur.
URBAN HEAT ISLAND
Although the City’s Mediterranean climate includes high temperatures during summer and fall months, the City’s urban land use patterns can intensify periods of extreme heat through the “urban heat island” (UHI) effect. The UHI
effect is generally understood as the phenomenon of urban areas being significantly warmer than surrounding rural areas because of human activity and land use patterns in the built environment. Several factors contribute to the
effect, with the primary cause being changes in land surfaces (EPA 2008). The albedo of a surface is the measure of
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the ability to reflect or absorb solar radiation, with darker surfaces having a lower albedo and absorbing more solar radiation. As urban areas develop over time, resulting in the development of more land surfaces with low albedos (e.g., asphalt pavement, dark building surfaces), more solar radiation is absorbed in these materials causing increased
ambient temperatures and warmer nighttime temperatures. Another factor contributing to the UHI effect is the loss of evapotranspiration in urban areas. Evapotranspiration, the movement of water to the air from sources such as the soil, plants, and bodies of water, reduces ambient air temperatures (EPA 2008). As cities grow and often reduce the
extent of available vegetation that contributes to evapotranspiration, UHI effects are exacerbated. Additionally, waste heat from human activities involving machinery (e.g., vehicle traffic, using air conditioning, industrial activity) can also contribute to the UHI effect, with excess heat absorbed by surrounding surfaces (Sailor 2011; Zhu et al. 2017).
Several factors contribute to the UHI effect, including land use patterns; the presence of large, paved areas (e.g., roads and parking lots); traffic from high-volume roadways (Zhu et al. 2017), impervious surfaces (e.g., roofs); and the
presence of vegetation and trees, which contribute to evapotranspiration. All these factors affect surface temperatures in urban areas. To show how the UHI effect is affecting various parts of the City, Figure 2-4 identifies
land uses in the City, street trees owned and maintained by the City data from The Trust for Public Land, which has developed maps to identify hot spots in cities with above-average temperatures compared to the City as a whole.
LONG-TERM DROUGHT
Long-term drought can have significant environmental, agricultural, health, economic, and social consequences. San Luis Obispo County, along with larger areas of California, experiences periods of long-term drought that stress the ecosystem and water supplies; and subsequently, impact agriculture, public health, and the economy. Notable multi-
year droughts that have affected the County and the City include:
1929 – 1934 – This statewide drought established the criteria commonly used in designing storage capacity and yield for large Northern California reservoirs; and hence, is one of the first major historic droughts noted in
California.
1975-1977 — From November 1975 through November 1977, California experienced one of its most severe droughts. In 1976 and 1977, the winters brought only one-half and one-third of normal precipitation, respectively.
1987-1992 — San Luis Obispo County suffered adverse effects resulting from this statewide drought, when low
precipitation and runoff levels greatly affected the Central Coast, adversely affecting about 30 percent of the state’s population, much of the dry-farmed agriculture, and over 40 percent of the irrigated agriculture.
2007 – 2009 – California proclaimed a statewide drought in 2009. The greatest impacts of this multi-year drought were suffered on the western side of the San Joaquin Valley, on agricultural communities where drought effects were coupled with the economic recession. Emergency response actions were necessary with regard to social
services.
2012 – 2017 – Drought produced severe impacts to water wells throughout the San Luis Obispo planning area, with a high number of wells running dry. Water allotments were drastically reduced in many towns and to water
agencies, with extremely high costs for procuring water. In addition, job loss occurred with many families requiring food supply and water supply assistance to homeowners experiencing dry wells. For the County of San
Luis Obispo, there were 13 disaster declarations from 2012–2017, though total associated financial losses across the various economic sectors is not available for all these recent drought-related declarations.
The City relies on regional water supplies, the four primary sources including Whale Rock Reservoir, Salinas Reservoir, Nacimiento Reservoir, and recycled water (City of San Luis Obispo 2019a). As discussed in Section 2.1.3, the UWMP, which evaluates the City’s current and projected water supplies through the year 2035, includes strategies to reduce
water demand and prepare for long-term drought scenarios. Water demand modeling estimates that these sources provide a 7.5-year combined water supply, assuming an extended worst-case historical drought (San Luis Obispo County 2019a).
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Source: Data received and downloaded from City of San Luis Obispo and the Trust for Public Land.
Figure 2-4 Urban Heat Island Effect and Tree Cover in the City
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COMMUNITY EXTREME HEAT CONCERNS
As part of the community priority survey, when participants were asked to report on their level of concern for extreme heat, as shown in Figure 2-5, 87 percent of respondents indicated that they were “Somewhat” or “Very”
concerned about the issue. Ninety percent of individuals indicated they had been “Somewhat” or “Very” impacted by extreme heat in the past 1-3 years. Additionally, individuals with a household income of less than $50,000 and
individuals between the ages of 18 and 24 had the highest level of concern for extreme heat. Individuals who note their housing situation as “Renter” or “Other” indicate the highest level of concern for extreme heat (i.e., 79 percent versus 58 percent for homeowners).
Sources: Resilient SLO Community Priorities Survey
Figure 2-5 City Resident’s Extreme Heat Concern and Impact
2.3.4 Wildfire
A wildfire is defined as an uncontrolled fire spreading through vegetative fuels that poses a threat to life and/or property (San Luis Obispo County 2019b). Wildfires can be ignited by natural events, such as lightning strikes, or can
be caused by damaged infrastructure (e.g., downed power lines) or human activities (e.g., campfires, arson). Wildfires can move quickly, casting embers into downwind areas, and spread to developed areas, putting human live and
properties at risk.
Three factors that contribute significantly to wildfire behavior are topography, fuel, and weather:
Topography—An area’s terrain and slope affect its susceptibility to wildfire spread. Both fire intensity and the rate of spread increase as slope increases because heat from a fire tends to rise through convection. For this reason, wildfires tend to spread more slowly downhill. The arrangement of vegetation on a hillside can also contribute to
increased or decreased fire activity on slopes.
Fuel—The type, condition, and volume of fuel material are key factors that influence wildfire behavior. Fuel
sources are diverse and can include dead vegetative matter, live trees, brush, and cured grasses. Buildings and other structures, such as homes, can also be sources of fuel. Certain types of plants are more susceptible to burning or will burn with greater intensity, and dead, dry plant matter tends to burn more easily than living plant
13%18%
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80%
Not at all Somewhat VeryPercent of RespondentsLevel of Concern
EXTREME HEAT CONCERN & IMPACT
Which of the following climate change impacts are you concerned about [Extreme Heat]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Extreme Heat]?
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matter. Thus, fire risk is increased significantly during periods of prolonged drought. The density of vegetation increases the amount of combustible material available, also called the fuel load.
Weather—Factors such as temperature, humidity, wind, and the occurrence of lightning affect the potential for
wildfire and its spread. High temperatures and low humidity can dry out wildfire fuels, creating a situation in which fuel will ignite more readily and burn more intensely. Thus, wildfire risk increases during periods of drought. Wind is one of the most significant weather factors in the spread of wildfires. Higher wind speeds lead
to faster wildfire spread and, oftentimes, greater fire intensity.
Environmental and climatic conditions in and around the City influence the frequency and magnitude of wildfires. The
City often experiences high-wind events, such as the Santa Lucia winds, which originate inland and flow westward during the late summer and early fall, counter to the prevailing westerly winds that occur throughout much of the year. Santa Lucia winds contain little humidity, and summers in the City are hot and dry, with precipitation primarily
occurring in the winter months. Thus, the combination of the relatively hot, dry Santa Lucia winds occurring at a time when vegetation in the County and the City is particularly dry following the summer months can contribute to the
ignition and spread of large wildfires. Periods of low relative humidity, when dead trees and vegetation cannot absorb moisture from the air, can also increase the risk of wildfires (City of San Luis Obispo 2011).
The risk of wildfires and subsequent impacts to property and life is greatest at the wildland-urban interface (WUI), which is where urban development borders wildland fuels. Wildfire risk is compounded in areas of the WUI that are also located in or near High or Very High Fire Hazard Severity Zones. Figure 2-6 includes CAL FIRE designated Fire
Hazard Severity Zones in and surrounding the City. Portions of southwestern and northeastern parts of the City are located in or near a Very High Fire Hazard Severity Zones, and many of these portions of the City overlap with the WUI. Locations identified by CAL FIRE as Hazard Severity Zones for the City and County are identified in Appendix A. Beyond these areas of the City, the risk of urban fires decreases, with most of the areas surrounding the City located in a Moderate Fire Hazard Severity Zone.
Figure 2-7 shows the locations of fires that have occurred within 10 miles of the City between 1900 and 2020. Four fires (labelled in Figure 2-7) have occurred within City boundaries. Between 1900 and 2018, 490 wildfires have been
recorded in the County (San Luis Obispo County 2019a). Notable fires that have occurred in the County include the Weferling fire (1960), the Las Pilitas fire (1985), the Chispa fire (1989), the Highway 41 fire (1994), the Highway 58 fire (1996), the Logan fire (1997), and the Chimney fire (2016). In total, these fires burned approximately 400,000 acres,
destroyed numerous structures, and cost millions of dollars to suppress (City of San Luis Obispo 2019b). The Las Pilitas fire burned 75,000 acres and burned within City limits, damaging a number of structures (City of San Luis Obispo 2011). The 1994 Highway 41 fire burned more than 50,000 acres close to the City’s northern boundary and destroyed 42 homes, 61 other structures, and 91 vehicles (San Luis Obispo County 2019a).
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Source: San Luis Obispo County 2019a
Figure 2-6 Wildfire Hazard Severity Zones In and Surrounding the City of San Luis Obispo with Critical Facilities
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Sources: Data downloaded from CalFire in 2020
Figure 2-7 Wildfire Perimeters for Wildfires within 10 Miles of the City of San Luis Obispo (1900–2020)
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WILDFIRE MANAGEMENT
The City’s Fire Department is the main agency responsible for wildfire response, management, and mitigation in the City, with many fires being addressed through mutual aid by both the City’s Fire Department and CAL FIRE. Several
agencies, including the County, provide support to incorporated areas, including the City, during wildfire events. Supporting agencies, such as CAL FIRE, are also available to mobilize during fire response if needed. In addition to
having the authority to declare local emergencies, the County can provide support for evacuations, shelter, and other forms of assistance for municipalities, including the City (San Luis Obispo County 2016). The City can also declare a disaster declaration through the City’s Disaster Council, absent the County. Because fire risk is highest for regions of the City within the WUI, the City has produced detailed maps of these regions, indicating evacuation routes and other critical information for responders. Locations identified by CAL FIRE as Hazard Severity Zones for the City and County
are identified in Appendix A. The City’s Community Wildfire Protection Plan serves as the primary document for assessing wildfire risk in different areas in the City and helping to implement a series of policies and strategies to reduce this risk. These policies, along with corresponding strategies, include:
Education - The goal of the Education policies and strategies are to prepare response organizations, communities, the public, and policy makers regarding appropriate community actions and interactions to reduce
the unwanted impacts of fires in the WUI.
Fuel - The goal of the fuel policies and strategies are to mitigate the unwanted impacts of wildfires on communities through proper vegetation management techniques that reduce hazardous fuels and the resulting wildfire intensity.
Planning - The goal of the planning policies and strategies are to mitigate the unwanted impacts of wildfires on communities through community planning (including new resilient community design, retrofitting existing communities, and community recovery from the impact of fire), response planning, evacuation planning, and
preparedness planning for responders, communities, and individuals and animals and livestock.
Response - The goal of the response policies and strategies are to mitigate the unwanted impacts of wildfires on life, property and resources by having an efficient and effective response that includes properly trained personnel, appropriate equipment, and a community prepared to take appropriate action or evacuation.
Ignition Resistance - The goal of the ignition resistance policies and strategies are to eliminate or mitigate structural ignitions from radiant heat, flame contact, or embers from WUI fires.
WILDFIRE SMOKE
While the City is at risk from the impacts of wildfires, the City and its residents are also susceptible to impacts of
smoke from wildfires in the coastal mountain ranges of central California and the Los Padres National Forest to the east of the City. Wildfire smoke in the surrounding region and, due to wind patterns, wildfires along the central coast in general, can greatly reduce air quality in the City and cause public health impacts as well as impacts to tourism and
normal community functions. Community public health factors that can increase the impacts of wildfire smoke include the prevalence of asthma in children and adults; chronic obstructive pulmonary disease; hypertension; diabetes; obesity; percent of population 65 years of age and older; and indicators of socioeconomic status, including poverty, income, and unemployment. Exposure to wildfire smoke, particularly exposure to vulnerable populations, can result in worsening of respiratory symptoms, increased rates of cardiorespiratory emergency visits, hospitalizations, and even death (Rappold et al. 2017). In the summer of 2020, wildfire smoke alerts were issued for San Luis Obispo County due to poor air quality caused by the Dolan Fire near Big Sur (The Tribune 2020a). Wildfire smoke can also have impacts on the labor market and the economy in general, with air quality affecting the ability of outdoor workers to perform their work and impact industries that operate in the open air (e.g., wineries, recreation
activities, sporting events) (Borgschulte et al. 2019).
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COMMUNITY WILDFIRE AND WILDFIRE SMOKE CONCERNS
As part of the community priorities survey, when asked about their concern for wildfires and wildfire smoke, as shown in Figure 2-8, 94 percent of participants indicated “Somewhat” or “Very”. When asked about whether they have been
personally affected by either event, 64 percent of respondents indicated “Somewhat” or “Very” for wildfires and 92 percent of respondents indicated “Somewhat” or “Very” for wildfire smoke. Additionally, wildfire smoke was of
paramount concern for individuals within the lowest income group (i.e., 84 percent). Renters and individuals between the ages of 18 and 24 expressed the highest level of concern for wildfire and wildfire smoke. Individuals who identify as White or Caucasian express a slightly higher level of concern both wildfire and wildfire smoke than individuals who identify as all other Races/Ethnicities.
Sources: Resilient SLO Community Priorities Survey
Figure 2-8 City Resident’s Wildfire and Wildfire Smoke Concern and Impact
5%
16%
79%
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20%
74%
35%43%
21%
7%
39%
53%
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Not at all Somewhat VeryPercent of RespondentsLevel of Concern
WILDFIRE SMOKE & WILDFIRES
Which of the following climate change impacts are you concerned about [Wildfire]?
Which of the following climate change impacts are you concerned about [Wildfire Smoke]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo
[Wildfire]?
Which of these hazards have you been personally affected by in the past 1-3 years in the City of San Luis Obispo [Wildfire
Smoke]?
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3 SENSITIVE INFRASTRUCTURE, POPULATIONS,
AND FUNCTIONS
This section discusses the City’s transportation and built environment; critical facilities and infrastructure, socioeconomic trends and vulnerable populations, and community and economic functions that could be affected by climate change. It helps develop a comprehensive understanding of the City’s infrastructure and facilities,
populations, and functions that are vulnerable to the impacts of climate change in order to understand how and why potential impacts may occur in the future and determine how these effects compare to baseline conditions. The specific topics discussed in this section were based on guidance in the APG and he FHWA’s Vulnerability Assessment and Adaptation Framework, which provides guidance on assessing the climate vulnerabilities of the transportation system (FHWA 2017).
3.1 TRANSPORTATION SYSTEM AND BUILT ENVIRONMENT
This section provides an overview of the City’s built environment, which includes the transportation network; utilities
infrastructure; and critical facilities, such as police and fire stations, hospitals, community centers, and libraries. It also describes the City’s existing transportation system, as well as the regional transportation network, focusing on physical infrastructure and facilities (e.g., bridges, roadways) and transportation behavior and trends (e.g., commute
behavior, mode share, traffic on high-volume roadways) that are anticipated to be affected by climate change. It includes an analysis of all modes of transportation (e.g., driving, cycling, walking). This section also catalogs critical
facilities and infrastructure in or near the City that may be affected by existing or future climate-related hazards. Critical facilities, for the purposes of this Report, are consistent with the critical facilities that provide essential public health and safety functions and included in the City’s HMP.
3.1.1 Transportation System
The City includes facilities to accommodate various modes of transportation, including automobiles, local and regional transit, and walking and biking. Understanding the location and condition of transportation resources responsible for the movement of people and resources throughout the City is a key component when preparing for
an emergency response during hazard events.
STREET NETWORK
The City contains several major transportation corridors, including U.S. 101, State Route (SR) 1, and SR 227. Most local streets have transportation infrastructure to support travel by multiple modes, including driving, walking, bicycling,
and transit. There are 76 traffic signals throughout the City to assist in traffic management. Table 3-1 provides the level of service and annual average daily traffic figures for major highway segments in the City. Figure 3-1 shows
traffic volume for U.S. 101, SR 1, SR 227, and local streets. The major regional arterials and highways that have the greatest volumes are Santa Rosa Street, Madonna Road, Broad Street, and Los Osos Valley Road.
Table 3-1 Annual Average Daily Traffic and Level of Service of Highway Segments in San Luis Obispo
Highway or State Route Segment Number of Lanes Level of Service Annual Average Daily Traffic
U.S. 101 S. Higuera to Monterey Road 4 D 70,000
SR 227 Los Ranchos Road to Tank Farm Road 2/3/4 F 20,000
SR 227 Tank Farm Road to Higuera Street 4 D 18,000-30,000
SR 1 U.S. 101 to Highland Drive 4 F 33,000-37,000
Source: City of San Luis Obispo & San Luis Obispo Council of Governments 2019
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 3-1 Major Roadways in San Luis Obispo by Traffic Volume
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BICYCLE NETWORK
The City has a well-established bicycle network that offers both separated and shared street space. There are also ample bicycle parking racks throughout the City, primarily in the downtown area. The different types of bicycle
facilities are described below and shown in Figure 3-2:
Class I Bikeways (Shared-Use Paths): Class I bikeways provide a separate right-of-way and are designated for bicycle and pedestrian use only. These paths serve corridors where there is enough right-of-way, or space, to allow them to be constructed or where on-street facilities are uncomfortable because of vehicular volumes,
speeds, or other roadway characteristics.
Class II Bikeways (Bicycle Lanes): Class II bikeways are dedicated lanes for bicyclists generally adjacent to the outer vehicle travel lanes. These lanes have special lane markings, pavement legends, and signage.
Class III Bikeways (Bicycle Routes and Neighborhood Greenways): Class III bikeways are designated by signs or
pavement markings for shared use with motor vehicles but have no separated bike right-of-way or lane striping. Class III bikeways provide a connection to other portions of the bike network but are located in places where dedicated facilities are infeasible or designate preferred routes for bicyclists through high-demand corridors. The
City’s Bicycle Transportation Plan also includes neighborhood greenways, a type of Class III bikeway that is further prioritized for bicycle and pedestrian travel, often including traffic volume and speed management elements, branded signs and pavement markings.
Class IV Bikeways (Protected Bike Lanes or “Cycle Tracks”): Class IV bikeways provide a right-of-way designated exclusively for bicycle travel in a roadway and are protected from other vehicle traffic by physical barriers,
including, but not limited to, flexible posts, raised curbs, or parked cars.
As shown in Figure 3-2, there are several Class I through III bikeways proposed throughout the City as identified in the City’s current Bicycle Transportation Plan (2013). The City is currently in the process of updating the Bicycle
Transportation Plan and incorporating a pedestrian component, creating the City’s First Active Transportation Plan (ATP). The ATP is anticipated to include further focus on planning physically-separated bikeways and pedestrian
pathways and is planned for City Council consideration, and potential adoption in early 2021.
PEDESTRIAN NETWORK
The pedestrian network in San Luis Obispo is well established with numerous sidewalks, multiuse trails, and hiking trails located throughout the City. Areas lacking pedestrian infrastructure are generally located in the northeastern part of the City. Figure 3-3 shows the pedestrian network, highlighting areas without sidewalks and showing existing
Class I multiuse trails.
TRANSIT AND AIRPORT SERVICES
The City operates the SLO Transit bus service, which provides daily fixed-route transit services in the City and to the adjacent Cal Poly campus. According to the 2017–2020 Short Range Transit Plan (City of San Luis Obispo 2017), SLO Transit operates with varying service levels 7 days a week, with a fleet of 17 vehicles. SLO Transit completes more than
1 million passenger trips annually, defined as the total number of passenger boardings. The San Luis Obispo Regional Transit Authority (RTA) provides bus services in the County and provides connections between SLO Transit and RTA routes in the City’s Downtown Transit Center. Figure 3-4 highlights transit service in the City and includes RTA regional routes that serve the City.
In addition to SLO Transit and RTA, Greyhound provides regional and long-distance bus routes via a stop in the City. The City also includes an Amtrak train station, which provides regional and interstate rail service to residents and visitors along railroad tracks owned and operated by the Union Pacific Railroad. The City’s train station is located just
a few blocks away to the southeast of downtown.
The City and County are served by the County-owned Regional Airport. The airport allows people to fly private aircrafts and to use commercial carriers to connect with national and global commercial carriers.
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 3-2 Existing and Proposed Bikeways
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 3-3 Pedestrian Infrastructure within San Luis Obispo
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 3-4 Public Transit Routes within San Luis Obispo
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MODE SHARE
As shown in Figure 3-5, the percentage of residents in the City who commute using a non-automobile mode, such as bicycling, transit, or walking, is approximately 18 percent. In comparison, approximately 8 percent of County residents
commute using a non-automobile mode. The share of City residents using transit is 3 percent, the share of residents walking to work is 7 percent, and the share of residents biking to work is 8 percent. Approximately 67 percent of
residents drive alone to work, while 8 percent carpool. Figure 3-5 shows the commute characteristics by mode in the City, compared to the County data.
Source: U.S. Census Bureau 2018
Figure 3-5 Commuting Characteristics by Mode in the City and County
HAZARD IMPACTS ON THE TRANSPORTATION SYSTEM
The transportation system facilitates movement of people and resources throughout the City and is both susceptible to existing hazards and a key component of effective emergency response during hazard events. Extreme heat
events, wildfires and floods pose a direct physical threat to transportation facilities and infrastructure, damaging or destroying transit facilities, bridges, and roadways. Additionally, hazard events outside of the region may affect
electricity infrastructure which could consequently affect electric ground transportation and transit absent strategic energy resilience efforts.
Transportation systems are designed and constructed to withstand certain variabilities in weather and temperature based on observations of historical weather trends for specific climate regions (Li et al. 2011). The performance of transportation assets may begin to decline when the severity of extreme heat periods exceeds historical ranges, for
example, risk of damage to bridges due to thermal expansion increases significantly at temperatures above 100°F (Cambridge Systematics 2015). The characteristics of extreme heat events will affect different transportation assets differently.
The City’s vulnerability to flooding impacts on the transportation system is largely dependent on the capacity of the City’s flood management system to handle large storm events. Impacts on the transportation system from flooding
events are generally caused by failures in a City’s stormwater management or flood management system. For a full
0%10%20%30%40%50%60%70%80%
Drove Alone
Carpooled
Public Transportation
Walked
Bicycle
Other
County of San Luis Obispo City of San Luis Obispo
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discussion of the City’s flood management system, see Section 2.3.2. When flooding does occur on roadways, impacts can include increased risk of roadway collisions, increased congestion due to road closures, and erosion of roadway materials (i.e., roadway subbase materials) that can cause increased roadway degradation overtime (Caltrans
2013). Figure 3-6 overlays the FEMA 100- and 500-year flood zones over the state and local bridges within the City boundary and the City’s sphere of influence. As described in greater detail in Section 2.2.2, “Flooding,” flood zones are located primarily along the San Luis Obispo Creek and Brizzolara Creek.
Extreme heat caused by wildfires can cause damage to roadway assets such as guard rails and signage. Route closures during or after major wildfire events can cause increased traffic congestion or travel time delays. Additionally, post-wildfire runoff, in which fire-scarred slopes produce mudslides and debris flows during storm events can also cause road closures and transportation system delays (Caltrans 2013).
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Sources: Data downloaded from City of San Luis Obispo in 2020 and County of San Luis Obispo in 2020
Figure 3-6 Transportation Infrastructure and Facilities and Flood Zones
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3.1.2 Critical Facilities and Infrastructure
Critical facilities and infrastructure provide essential services to the public, such as preserving the quality of life and providing essential public safety, emergency response, and disaster recovery functions. Different types of critical facilities
include medical facilities, evacuation and community centers, potable water and wastewater facilities, fire stations, and local law enforcement stations. The County’s HMP organizes critical facilities the following four categories:
Emergency Services – Facilities or centers aimed at providing for the health and welfare of the whole population (e.g., hospitals, police, fire stations, emergency operations centers, evacuation shelters, schools).
Lifeline Utility Systems – Facilities and structures such as potable water treatment plants, wastewater, oil, natural
gas, electric power and communications systems.
Transportation Systems – These include railways, highways, waterways, airways, and city streets to enable
effective movement of services, goods and people.
High Potential Loss Facilities – These include nuclear power plants, dams, and levees.
Transportation infrastructure is discussed in greater detail in Section 3.1.1, “Transportation System.” Table 3-2 includes the City’s critical facilities and infrastructure are that have been evaluated for their replacement value and are included in Appendix G of the HMP.
Table 3-2 Critical Facilities and Infrastructure in the City of San Luis Obispo
Category Facility/Infrastructure Asset Replacement Value
Community and Recreational Facilities
City Hall $9,287,080
Library $1,604,146
Ludwick Community Center $2,559,501
Meadow Park Recreational Center $1,448,126
Mitchell Park Senior Center $1,068,158
Sinsheimer Pool and Park $2,623,419
Medical Facilities Sierra Vista Regional Medical Center N/A
French Hospital Medical Center N/A
Schools
California Polytechnic State University N/A
Cuesta College N/A
Laguna Middle School N/A
San Luis Obispo High School N/A
Infrastructure
Critical Bridges Varies
Essential Bridges Varies
Higuera Box Culvert $4,500,000
Evacuation Route Roads $50,000,000
Other Essential City-Owned Roads $120,000,000
Communication Towers N/A
Other City-Owned Facilities
City Corporation Yard $4,884,929
Community Development and Public Works Administration $23,081,375
Parking Garages $31,674,135
Parks and Recreation Building $1,282,662
Prado Day Center $669,393
Utilities Administration $1,060,252
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Category Facility/Infrastructure Asset Replacement Value
Police and Fire Stations
Dispatch Center $6,701,098
Fire Station #1 $5,483,205
Fire Station #2 $511,872
Fire Station #3 $594,009
Fire Station #4 $507,087
Police Main Building, Garage, Annex $4,854,341
Potable Water and Wastewater Facilities
Fire Station #4 Well N/A
Pacific Beach Well N/A
Reservoirs N/A
Eight Sewer Lift Stations N/A
Sewer System Infrastructure (pipes) – Approx. 140 miles N/A
Water Resource Recovery Facility $77,296,765
Seven Water Pump Stations N/A
Water System Infrastructure (pipes) – Approx. 180 miles N/A
Eleven Treated Water Storage Tanks N/A
Water Treatment Plant $51,486,423
Note: N/A = not available.
Source: Modified from Table G.9 in San Luis Obispo County 2019b
The San Luis Obispo Water Resource Recovery Facility (WRRF) is the City’s only facility that is classified as a high potential loss facility, which is defined as a critical facility that presents a significant risk to the surrounding area if damaged (e.g., dams, nuclear power plants). Keeping wastewater contained is vital because wastewater contains
contents such as human and animal waste, food scraps, oil, pesticides, fertilizers, heavy metals, and chemicals. Additionally, pathogenic bacteria, fungi, parasites, and viruses can live in wastewater before it is treated. In the event of a spill, untreated wastewater can contaminate surface water and groundwater resources and cause environmental
and public health impacts, including contaminate drinking water, spread disease, cause algae blooms in waterways, and release toxic gases and odors. Flooding risk is relatively high for the WRRF because the facility is located within a 100-year floodplain with moderate liquefaction risk (San Luis Obispo County 2019b). Therefore, it is especially critical that mitigating the risks of flooding and liquefaction is prioritized for this facility.
HAZARD IMPACTS ON CRITICAL FACILITIES
Critical facilities and infrastructure are instrumental in the City’s ability to respond to hazards that are affected by climate change. For this reason, they are given special consideration when planning and preparing for hazards so that these
critical assets are not damaged and remain operational, especially during emergency events. Large flooding can cause significant issues for some critical facilities, specifically those involved in emergency services such as fire departments or
police stations. Table 3-3 includes the name and type of facilities within the City that are within the 100-year and 500-year flood zones. Table 3-4 includes the name and type of facilities that are within the High and Very High Hazard Severity Zone designations which have been developed by CAL FIRE and discussed in detail in Section 2.3.4.
The risk of specific critical facilities to hazards is largely dependent on the type of critical facility and hazard affecting that facility. Both wildfires and floods can pose a direct physical threat to critical facilities and critical infrastructure, causing damage to or destroying buildings and structures and, subsequently causing disruptions to operation of those facilities during emergency events as well as day-to-day operations. Precipitation events, preceded by wildfires, can cause post-wildfire runoff events, placing increased stress on City infrastructure by causing increased erosion, increased siltation in waterways, increased risk of flooding from debris flow, and decreased water quality in rivers and streams. Extreme heat events can cause increased demand on utility infrastructure (e.g., increased electricity demand
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for cooling) as well as cause increased demand on emergency services (e.g., increased hospital room visits). Impacts on the City’s critical facilities can cause compounding effects on other community functions in the City. For example, impacts and disruptions to City’s electricity grid will in turn affect businesses resulting in a potential loss of economic
activity. These cascading effects will be explored further in later stages of the Resilient SLO project.
Table 3-3 Critical Facilities Located in 100-Year and 500-Year Flood Zones
Facility/Infrastructure Asset Name Asset Type Asset Category Located in 100-Year Flood Zone Located in 500-Year Flood Zone
San Luis Obispo WRRF Waste Water Treatment Plant Lifeline Utility Systems Yes Yes
N/A Microwave Service Towers Lifeline Utility Systems Yes Yes
N/A Microwave Service Towers Lifeline Utility Systems Yes Yes
N/A Microwave Service Towers Lifeline Utility Systems Yes Yes
Laurus College Colleges / Universities Emergency Services Yes Yes
Pacheo Elementary School Day Care Facilities Emergency Services Yes Yes
The Manse on Marsh Nursing Homes Emergency Services Yes Yes
San Luis Veterans Clinic VA Medical Facilities Emergency Services Yes Yes
N/A Microwave Service Towers Lifeline Utility Systems No Yes
Central California School Colleges / Universities Emergency Services No Yes
CL Smith Elementary School Day Care Facilities Emergency Services No Yes
Old Mission School Private Schools Emergency Services No Yes
Note: N/A = not available, WRRF = Water Resource Recovery Facility.
Source: Data retrieved from San Luis Obispo County 2019b
Table 3-4 Critical Facilities Located in Very High or High Fire Hazard Severity Zones
Facility/Infrastructure Asset Name Asset Type Asset Category Fire Hazard Severity Zone
Very High High
7 Microwave Service Towers Microwave Service Towers Lifeline Utility Systems Yes Yes
9 Microwave Service Towers Microwave Service Towers Lifeline Utility Systems No Yes
Garden Creek Nursing Homes Emergency Services No Yes
San Luis Obispo High School Public School Emergency Services No Yes
Pacific Beach High School Public School Emergency Services No Yes
Love to Learn Day Care Facilities Emergency Services No Yes
Old Mission Preschool Day Care Facilities Emergency Services No Yes
San Luis Obispo Classical Academy Day Care Facilities Emergency Services No Yes
Blue Sky Preschool Day Care Facilities Emergency Services No Yes
Cal Poly Preschool Lab Day Care Facilities Emergency Services No Yes
Love to Learn Day Care Facilities Lifeline Utility Systems No Yes
SLO Christian Academy Private Schools Emergency Services No Yes
SLO County Psychiatric Health Facility Hospitals Emergency Services No Yes
Medical Stop Urgent Care Service Urgent Care Emergency Services No Yes
Teach Elementary Public Schools Emergency Services No Yes
Peep – De’Groot Prepare School Public Schools Emergency Services No Yes
Clark Field (Historical) Airport Transportation Systems No Yes
Note: N/A = not available, WRRF = Water Resource Recovery Facility.
Source: Data retrieved from San Luis Obispo County 2019b
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3.2 SOCIOECONOMIC TRENDS AND VULNERABLE POPULATIONS
Certain populations in urban areas are particularly vulnerable to a variety of hazards that are likely to be exacerbated by climate change. Vulnerabilities can include being disproportionately exposed to hazards and environmental
pollution; being more sensitive to impacts because of preexisting health conditions; or having less resources or opportunities to prepare for and recover from hazard impacts. Vulnerable populations often include persons over the age of 65, infants and children, individuals with chronic health conditions (e.g., cardiovascular disease, asthma), low-
income populations, athletes, and outdoor workers (CDC 2019). More broadly, any trait that would limit or prevent people from avoiding a hazard, seeking medical attention, or obtaining essential food, supplies, and/or care in an emergency would make them vulnerable to hazards.
The HPI score for the City combines 25 community characteristics across eight areas (i.e., economic, social, education, transportation, neighborhood, housing, clean environment, and health care) into a single indexed score correlated to
life expectancy at birth. The HPI score ranking for the combined census tracts in the City places it in the 61st percentile, meaning it has healthier community conditions than 61 percent of other California census tracts. Although certain geographic areas and populations may be more vulnerable than others, by identifying these specific populations or geographic areas, the City can work to address these vulnerabilities and, in turn, make the whole community more resilient.
Compared to the City’s overall HPI score, the City is doing particularly well in terms of education, performing better than 78 percent of other California census tracts in terms preschool enrollment and residents with a bachelor’s
degree or higher. However, the City ranks lower in terms of the economic factors score (39th percentile overall), which includes factors such as median household income, unemployment rate, and population with an income exceeding
200 percent of federal poverty level. The City also ranks low in terms of the housing factors score (17th percentile overall), which includes indicators such as housing habitability and low-income homeowners with a severe housing
burden (HPI 2020). This summary provides highlights of the City overall HPI score. To see all information on individual indicators, visit the California HPI website (https://map.healthyplacesindex.org/).
3.2.1 Population Overview
The U.S. Census bureau estimates the City’s population to be 47,459 persons as of July 2019 (U.S. Census Bureau 2019). Table 3-3 illustrates the City’s demographics by sex, race, and age according to the U.S. Census. As shown, the
large majority of residents identify as white with those identifying as Hispanic being the second largest demographic group. In terms of youth and elderly populations, 29 percent of City residents are either under 18 years or over 65 years old. The City is highly educated: 93 percent of the population over 25 years old has at least a high school
degree, and 50 percent of the population over 25 years old has a bachelor’s degree or higher (U.S. Census Bureau 2018). More specific information regarding the City’s demographics will be explored further in the forthcoming
Resilient SLO Hazards and Vulnerabilities Report.
Table 3-3 City Demographics by Sex, Race, and Age
Demographic Characteristics City of San Luis Obispo San Luis Obispo County California
Population 47,459 283,111 39,512,223
Male 51% 51% 50%
Female 49% 49% 50%
White alone 84% 89% 72%
Hispanic or Latino 18% 23% 39%
Asian alone 6% 4% 16%
Two or more races 4% 4% 4%
Black or African American alone 2% 2% 7%
American Indian and Alaska Native alone 0.4% 1.4% 1.6%
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Demographic Characteristics City of San Luis Obispo San Luis Obispo County California
Persons under 5 years 3% 5% 6%
Persons under 18 years 13% 18% 23%
Persons 65 years and older 13% 21% 15%
Source: U.S. Census Bureau 2019
HOME OWNERSHIP
In 2019, the City had a total of 21,416 housing units (City of San Luis Obispo 2018). According to the 2018 American Community Survey, 91 percent are occupied and 9 percent are vacant. Homeownership versus renting provides a
number of benefits including greater housing security, the ability to implement home improvement projects (e.g., energy efficiency improvements), and the ability to use a home to access financial resources (Brookings Institute
2018). The majority of housing units are rented (62 percent), while 38 percent are owned. Around 8 percent of occupied households do not have access to at least one automobile, and around 2 percent of occupied housing units have no telephone service available (U.S. Census Bureau 2018). Those who own homes, in general, have easier access to equity in their homes which provides more flexibility in emergency situations and are, therefore, less likely to become homeless from life events (Brookings Institute 2018).
HOUSING COSTS
Overall, the cost of living in San Luis Obispo is high relative to household income. Table 3-4 provides key information about housing costs in the City. As shown in Table 3-5, around 57 percent of renters spend 35 percent or more of their income on rent (U.S. Census Bureau 2018). Around 6 percent of all families and 14 percent of families with a
female single parent had an income that fell below the poverty level in the span of a year (U.S. Census Bureau 2018).
Table 3-4 Housing Cost Characteristics
Housing Characteristic Housing Cost
Median monthly cost for owners with a mortgage $2,340
Median monthly cost for renters $1,461 per unit
Median household income $52,740
Source: U.S. Census Bureau 2018
As illustrated in Figure 3-7, the City has a substantial low-income population, as mapped consistently with definitions provided in Assembly Bill 1550, which defines low-income communities as census tracts with median household
incomes at or below 80 percent of the statewide median income or with median household incomes at or below the threshold designated as low income by the California Department of Housing and Community Development’s list of
state income limits adopted pursuant to California Code Section 50093. As demonstrated in Figure 3-7, this population is located primarily in the northern and central parts of the City.
Table 3-5 Gross Rent as a Percentage of Monthly Household Income
Housing Characteristic Percent of Occupied Units
Less than 15 percent 7%
15 to 20 percent 8%
20 to 25 percent 9%
25 to 30 percent 13%
30 to 35 percent 6%
35 percent or more 57%
Source: U.S. Census Bureau 2018
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Source: CalEPA 2020
Figure 3-7 Low-Income Communities as Defined under Assembly Bill 1550
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Research has found that housing affordability is one of the strongest predictors of rates of homelessness in a community, with higher median rents leading to higher rates of homelessness and higher rates of sheltered homeless populations. To better understand the issue of homelessness, the U.S. Interagency Council on Homelessness
categorizes homeless individuals in three basic groups: chronically homeless (i.e., people who have experienced long-term homelessness), episodic homeless (i.e., people who alternate between permanent housing and supportive housing or shelters), and transitional homeless (i.e., people who become temporarily homeless because of an event,
such as loss of employment) (U.S. Interagency Council on Homelessness 2009). There are approximately 482 homeless individuals in the City (City of San Luis Obispo 2020a).
EMPLOYMENT
Employment characteristics of City residents can highlight key vulnerabilities to climate impacts. Below are some examples of key employment characteristics for City residents as well as jobs located in the City.
Resident Employment Characteristics
Of the City’s population over 16 years of age, approximately 60 percent are employed, 2 percent are unemployed, and 38 percent are not in the labor force (e.g., students) (U.S. Census Bureau 2018).
Typically, without considering the impact of COVID-19, around 3 percent of workers use public transportation to
commute to work, 76 percent drive (combined alone and carpooled), 7 percent walk, 9 percent commute via other means, and around 5 percent work from home (U.S. Census Bureau 2018).
Approximately 2 percent of the employed population works in the agriculture, forestry, fishing, hunting, and mining industries, and around 4 percent work in the construction industry (U.S. Census Bureau 2018). These workers generally work outdoors more often and for longer periods than other professions and are therefore,
often have higher exposure to hazards, including extreme heat and wildfire smoke.
City Employment Industries
The City serves a regional employment center for the County with a jobs-to-housing ratio of 2.7 jobs (including
Cal Poly and the Men’s Colony) for every one housing unit (City of San Luis Obispo 2018), illustrating the influx of workers from other areas in the County and elsewhere into the City for employment opportunities.
In 2018, the largest employment industries in the City were the educational services industry (15 percent), accommodations and services (15 percent), retail trade (12 percent), and health care and social services (12 percent) (U.S. Census Bureau 2018).
DISABILITY STATUS
Individuals with disabilities, especially those who are also unemployed or underemployed, are especially vulnerable to climate hazards largely because they, along with youth and senior populations, often rely heavily on family or caretakers for transportation and other basic needs (e.g., taking medications, cooking food). Around 9 percent of the
City’s total civilian noninstitutionalized population has a disability, with the majority of these people 65 years and over. Around 35 percent of people 65 years and over in the City have reported having a disability (U.S. Census Bureau 2018).
HEALTH INSURANCE COVERAGE
People who do not have health insurance coverage are disproportionately at risk during emergencies because they may not be able to receive the care they need or be able to pay for treatment. Table 3-6 includes various sectors of the workforce without health insurance and insurance the vulnerability of unemployed residents to emergency hazard
events.
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Table 3-6 Health Insurance Coverage
Population Sector No Health Insurance Coverage (public or private)
Total Population 5%
Unemployed Residents 17%
Employed Residents 5%
Not in the labor force 7%
Source: U.S. Census Bureau 2018
HOUSEHOLD SIZE AND CHARACTERISTICS
Single parents are often the sole providers for their households, making the household increasingly susceptible if any major life event were to occur (e.g., an illness, job loss). Single parents also have an increased burden regarding
childcare, as they must be able to pay for childcare during work hours or be able to bring their children to work. Single-parent households also are likely to rely on only one source of income and are therefore, more likely to qualify
as low income. Around 10 percent of households have a single parent (4 percent male householder, 6 percent female householder) (U.S. Census Bureau 2018).
Elderly populations, especially those who live alone, have a preexisting health condition, or are not able to drive, are vulnerable to climate hazards because they may be more sensitive to extreme heat and may not have the ability to move or adapt as quickly during hazardous situations compared to others. Eleven percent of householders who live
alone are 65 years and over (U.S. Census Bureau 2018).
LANGUAGE
Cultural and linguistic isolation can make it difficult for people to access or understand important information regarding preparing for and responding to emergency situations. Approximately 6 percent of the City’s population
primarily speaks a language other than English and reports that they are able to speak English less than “very well” (U.S. Census Bureau 2018). Table 3-7 includes information about languages spoken in the City as well as what
percentage of residents that speak another language do not speak English “very well” and may experience linguistic isolation.
Table 3-7 Languages Spoken by City Residents
Language Spoken Percentage of Population Percentage of population that speak English less than “very well”
Speak only English 83% n/a
Speak Spanish 11% 33%
Other Indo-European Language 2.5% 26%
Asian-Pacific Island Language 3% 45%
Other Languages 0.5% 21%
Notes: n/a = not applicable
Source: U.S. Census Bureau 2018
STUDENTS
Young adults from the ages of 20–34 represent a large portion of the City’s population (42 percent of the total population) largely because of enrollment at two colleges, Cal Poly and Cuesta College, the City’s junior college (U.S.
Census Bureau 2018). University students often have less access to vehicles on campus. For example, students at Cal Poly are not allowed to keep cars on campus during their freshman year (Cal Poly n.d.). As part of Cal Poly’s emergency management planning, the university has contracted with multiple bus and shuttle companies in San Luis
Obispo County to provide emergency transportation services, if needed, and worked with the San Luis Obispo
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County Office of Emergency Services to ensure transportation resources would be available during large scale disaster events (Cal Poly 2018).
Generally, university students rely on on-campus housing or renting housing off campus. Because these students
often have less control over their housing conditions, they could potentially have a reduced ability to deal with extreme heat or other hazards. In 2017, a brush fire broke out adjacent to the Cal Poly campus, requiring an evacuation event for many of students living in on-campus housing, further highlighting the impacts of hazard events
on student populations. The two main universities located near the City are:
Cal Poly, whose campus is located adjacent to the City boundary to the northeast, hosts the most students of the
two schools with 20,503 total undergraduate students enrolled in fall 2019 (NCES 2020).
Cuesta College, whose total undergraduate enrollment for fall 2019 was 11,281 students, with the majority being
in state (96 percent) (NCES 2020).
As highlighted in the discussion above, there are several sectors of the City’s population to consider when identifying vulnerable populations in the City, as suggested by the APG. Potentially vulnerable populations in the City include:
low-income populations identified as part of Assembly Bill 1550,
populations experiencing linguistic isolation,
youth and senior populations,
populations without access to a vehicle or limited mobility,
people with disabilities or existing health conditions (e.g., asthma),
housing insecure or homeless populations,
populations living in coastal and inland
floodplains or along the WUI,
unemployed or underemployed populations,
people without access to affordable health care or food, and
outdoor and migrant workers.
3.2.2 Hazard Sensitivities for Vulnerable Populations
This sections provides a general discussion of how certain vulnerable populations may be at increased risk from climate-related hazards. The section is not intended to be an extensive analysis of all hazard sensitives for all
vulnerable populations in the City. A more in-depth analysis of specific risks for vulnerable populations in the City will be included in forthcoming steps of the Resilient SLO project.
EXTREME HEAT IMPACTS
Extreme heat most severely affects populations that are more prone to heat-related illness, populations who are more exposed to weather because of the nature of their work or living situation, and populations that are less able to adapt to extreme heat. For example, youth (i.e., infants and children up to 4 years of age), elderly populations (i.e.,
those over 65 years old), people who are overweight, and people who are ill or on certain medications are at high risk of experiencing heat-related illness and, therefore, have greater vulnerability compared to other groups (CDC 2012). Increased temperatures have been reported to cause heat stroke, heat exhaustion, heat syncope, and heat cramps,
with certain vulnerable populations at increased probability of experiencing these effects (Kovats and Hajat 2008). Extreme heat can also worsen air quality, quickening the production of ozone in areas with increased concentrations of ozone precursors (i.e., oxides of nitrogen and reactive organic gases) (Knowlton et al. 2004). Additionally, people who work outdoors (e.g., agricultural workers, construction, and utility workers) and homeless individuals are more likely to be exposed to the sun during extreme heat days, giving them exposure vulnerability.
Research has found that low-income residents spend a larger proportion of their income on utilities, including electricity used for cooling, with these residents being disproportionally affected during extreme heat events (Voelkel et al. 2018). Additionally, research has found that low-income neighborhoods can often have less tree coverage and park space, further contributing to the disproportionate impact on low-income residents (Zhu and Zhang 2008). Unhoused
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individuals are also at increased risk from extreme heat events with, generally, less access to places to cool off and health care resources during these events. Additionally, decreased access to transportation services can further increase exposure and health risks from extreme heat events for the unhoused community (Ramin and Svoboda 2009).
FLOOD IMPACTS
Flooding events can occur very suddenly and unexpectedly. People who live in or near flood zones, especially those who have limited mobility, are most at risk of injury or death. Homeless populations living along waterway embankments or in flood zones are also at high risk during flooding events. These populations, along with people
whose businesses are located in or near flood zones, are vulnerable to having their home or livelihood damaged or destroyed by flooding. Destructive floods can also affect the local economy when businesses or services must close for repairs or be rebuilt, in turn affecting low-income populations. When essential City infrastructure is affected by
floods (e.g., transportation infrastructure, utilities, water infrastructure), people can have a more difficult time obtaining food, water, or medications, and this difficulty can disproportionately affect those with disabilities and elderly people who rely more heavily on others for assistance and supplies.
WILDFIRES
Wildfires can have serious short- and long-term effects. Immediate effects of wildfires include decreased air quality, resulting in negative health impacts on local populations, especially those who have preexisting health conditions,
such as asthma. People who live within a High or Very High Fire Hazard Severity Zone and/or within the WUI are disproportionately vulnerable to wildfires. Impacts from wildfire events in and near urban centers can include loss of life, property damage, and damages to critical facilities and infrastructure. Regional and localized wildfires can also
result in secondary impacts, including road closures and subsequent disruptions to the transportation system, interruptions to typical economic and community functions, short and long-term housing shortages, and public health impacts from wildfire smoke. While the City is not at very high risk from the direct impacts of wildfires, the City’s location makes it susceptible to impacts of wildfire smoke from wildfires in the coastal mountain ranges of central California.
Community public health factors that can increase the impacts of wildfire smoke include the prevalence of asthma in children and adults; chronic obstructive pulmonary disease; hypertension; diabetes; obesity; percent of population 65
years of age and older; and indicators of socioeconomic status, including poverty, income, and unemployment. Exposure to wildfire smoke, particularly exposure by vulnerable populations, can result in worsening of respiratory symptoms, increased rates of cardiorespiratory emergency visits, hospitalizations, and even death (Rappold et al. 2017). Similar to flooding, wildfires can affect the local economy and damage infrastructure, in turn affecting low-
income populations and making it especially difficult for some people to obtain food, water, or medications.
3.3 COMMUNITY AND ECONOMIC FUNCTIONS
This section discusses important community functions (e.g., utility operations, emergency services) and economic functions (e.g., major employment sectors) that may be affected by existing hazards. Hazard planning is especially important for the City, as it is the civic, economic, and cultural hub of the Central Coast (San Luis Obispo County 2019b).
3.3.1 Community Functions
The City provides many essential services and employment opportunities to the broader County community and serves as the governmental and cultural hub of the Central Coast region. The City has multiple regionally significant
medical facilities, including two major private hospitals, as well as urgent care facilities, assisted living communities, and community health care centers. Notably, the Sierra Vista Regional Medical Center provides high-level medical
and urgent care services for the County, including the County’s only neurosurgery program, high-risk pregnancy program, dedicated pediatric unit, and neonatal intensive care unit (San Luis Obispo Chamber of Commerce 2020).
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The City also remains an important educational resource for the region. As discussed in Section 3.2, “Socioeconomic Trends and Vulnerable Populations,” the City is home to Cal Poly and Cuesta College. Cal Poly consistently ranks among the top public universities in the nation with renowned engineering, architecture, business, and agriculture programs.
The City’s Fire, Parks and Recreation, Police, Public Works, and Utilities Departments, among others, provide essential public services that make the City safe and enjoyable for residents and visitors of both the City and County. The City relies on regional water supplies, the four primary sources being Whale Rock Reservoir, Salinas Reservoir, Nacimiento
Reservoir, and recycled water (City of San Luis Obispo 2019a). Electric and gas utilities are provided by Pacific Gas and Electric Company.
The City not only provides high-quality services and a high quality of life to its residents, but also offers a unique travel destination for visitors from the United States and internationally. The City is located in a region that offers a variety of outdoor attractions including beaches, state parks, wineries, and outdoor recreational spaces for surfing,
hiking, and mountain biking. The City is also known as a tourist destination for its charming downtown, events such as the Thursday Night Farmers’ Market, historic Spanish mission, recreational trails, and a thriving wine industry,
including the following major attractions and community landmarks:
Mission San Luis Obispo de Tolosa: Founded in 1772, this historic mission was the fifth Spanish mission
constructed in California.
San Luis Obispo Wine Country: There are over 250 wineries throughout Paso Robles, Edna Valley, and San Luis
Obispo County that are national and international tourist destinations.
Recreation and Open Space: Recreational opportunities and natural open space is abundant in and around the City, with trails for hiking, cycling, and horseback riding, as well as City parks, hot springs, and golf courses.
Additionally, the City is located close to the coast, where residents and visitors can enjoy activities such as surfing, kayaking, or whale watching (City of San Luis Obispo 2020b).
COMMUNITY SERVICES
The City as well as community partners offer a number of community services which support the City’s overall community function. These services often focus on providing support to underserved community members who may not have equitable access to opportunities or service accessible to the general population. Included below is a list of
organizations and services offered to the community which helps support overall community function.
40 Prado Homeless Services Center - The Community Action Partnership of San Luis Obispo, in partnership with Community Health Centers, operates the 40 Prado Homeless Services Center which helps individuals and families
improve their health and stability and move them towards self-sufficiency. Services provided at the shelter include overnight accommodations (up to 100 beds), meals, showers, laundry, mail/phone services, access to case
management, primary medical care, and animal kennels
Housing Authority of San Luis Obispo - The Housing Authority of San Luis Obispo (HASLO) works to build and maintain affordable housing for citizens in the County. HASLO works with individuals and organizations to
provide housing, education, and employment opportunities for families of modest means to become self-sufficient and improve their quality of life.
SLO Food Bank - The SLO food bank provides food, supplies, and resources to over 80 different nonprofit organizations throughout the County. The organization also provides assistance to households applying for food
assistance as well as other services.
San Luis Obispo Chamber of Commerce - The San Luis Obispo Chamber of Commerce works to enhance the economic prosperity and community well-being of San Luis Obispo County by supporting and advocating for
local businesses. Members of the Chamber of Commerce are provided with business support services, networking opportunities, classes and trainings, and promotional services, all in support of helping local
businesses thrive.
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3.3.2 Economic Functions
The City is the economic center of the County with many County residents commuting to the City for employment opportunities. Fourteen of the top 25 employers in the County are located in the City (San Luis Obispo County
2019a). Cal Poly and Cuesta College provide the City and the surrounding region with a young and highly educated workforce. The City acquires the majority of its yearly revenue from sales and use taxes ($26 million), property taxes ($18 million), and fees and service ($14.5 million) (City of San Luis Obispo 2020c). Major economic industries in the
City include education, health care, tourism, and retail. Table 3-8 shows percentage of jobs by industry sector located in the City.
Table 3-8 Employment by Economic Sector in the City of San Luis Obispo for 2018
Industry Employment (% of total)
Education services, health care, and social assistance 26.40%
Arts, entertainment, recreation, and accommodation and food services 17.20%
Retail trade 12.80%
Professional, scientific, management, and administrative and waste management services 11.90%
Manufacturing 6.10%
Construction 4.40%
Other services, except public administration 4.40%
Finance, insurance, and real estate 3.80%
Public administration 3.80%
Transportation, warehousing, and utilities 2.90%
Wholesale trade 2.10%
Information 2.10%
Agriculture, forestry, fishing and hunting, and mining 1.90%
Source: U.S. Census Bureau 2018
EDUCATION
As the top employer in both the City and the County, Cal Poly is of significant local and regional economic importance. Student, faculty, staff, and visitor spending off campus generates substantial revenue for local businesses and landowners. Approximately $160.8 million was spent by students at off-campus businesses and for housing
during the 2012-2013 academic year, generating millions of dollars of tax revenue for the City, most notably from property and sales taxes (Cal Poly 2014). Cal Poly is also inextricably linked with the tourism industry, as many people
come to tour the school or visit friends and family attending the university.
TOURISM
Tourism is one of the most dominant economic strengths of the City, as demonstrated by the City’s high employment in retail, arts, entertainment, recreation, and accommodation and food service industries, shown in Table 3-4. The
City’s tourism sector largely relies on transportation infrastructure, weather, public spaces, the health and abundance of natural resources, and local attractions and services to maintain this vital industry. In the City’s 2018-19 budget, 25
percent of the City’s revenue came from sale tax while 10 percent came from the transient occupancy tax, generated from visitors staying at the various hotels in the City. As a result, the City relies heavily on tourism and regional visitors to provide important services to residents including public safety, street paving, bicycle, and pedestrian improvement,
and other City services. In November 2020, residents in the City voted to extend a voter-approved sales tax at a new 1.5 cent rate, previously set at 0.5 cents (The Tribune 2020b). Given the City’s heavy reliance on the tourism industry, the City is particularly vulnerable to climate impacts (e.g., wildfire) that would affect this industry.
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AGRICULTURE
Although agriculture is not a major employment sector within the City itself, agriculture is the predominant land use surrounding the City and generates significant economic value for the County. The top five crops and livestock
produced in the region by total crop value include grapes (for wine), broccoli, strawberries, avocados, and cattle. The grape and wine industry have large influence on agricultural production in the County with grapes alone accounting for
approximately 27 percent of all crop value in 2018, San Luis Obispo County produced one billion dollars in crop value, demonstrating the significance of agriculture in supporting the County’s economy (County of San Luis Obispo 2018).
HAZARD SENSITIVITIES ON COMMUNITY AND ECONOMIC FUNCTIONS
Flooding, extreme heat, drought, and wildfire can disrupt community and economic functions by damaging or destroying structures and infrastructure that are essential for providing those functions. In addition to the direct and immediate destruction of the structures and infrastructure that support community and economic functions, climate-
related hazards may have long-term indirect effects on the community. For instance, climate-related hazards could alter the visual aesthetic associated with the City (e.g., type/density of vegetation, scarring of the landscape from wildfire/brushfire events), causing a perceived change in attractiveness to prospective visitors and students, affecting
tourist- and education-related services, such as hotels, restaurants, retail, and universities.
Agriculture is a sector that is susceptible to climate-related hazards and even small changes in annual average temperatures and precipitation. Extreme heat results in higher evaporation rates, leading to decreased reservoir storage and soil saturation; can negatively affect plant growth and cattle health; and can increase the risk of certain pest infestations. Flooding can oversaturate soils, cause erosion of soils, and pose a threat to livestock in floodplains.
Wildfire and wildfire smoke can destroy or damage crops, injure or kill livestock, and destroy ranching and agriculture infrastructure (CEC 2012). Impacts on the agriculture industry would, in turn, affect the tourism industry because many
people visit the region for its wineries and other agricultural businesses.
The City’s economy has generally been stable in recent history, with the unemployment rate ranging from 4 percent to 5 percent from 2000 to 2007. The national economic recession in 2008 caused unemployment to increase to 9 percent in 2009 (City of San Luis Obispo 2010). The current economic impacts of COVID-19 are especially pronounced in the tourism industry because of travel restrictions, closures, and social-distancing requirements. Given potential
similarities in economic impacts between COVID-19 and certain hazards (e.g., wildfires and associated smoke), which place restrictions on businesses and households, it is important to understand and learn from how the City is being affected by the COVID-19 pandemic. Approximately 40 percent of the excess unemployment attributable to COVID-
19 in the United States is in the leisure and hospitality sector, compared to prepandemic conditions of 11 percent. This is notable based on the large portion of jobs in the City concentrated in the tourism and service industries. Future climate impacts, particularly those involving natural resources or affecting the ability of tourists to visit the City and surrounding areas (e.g., wildfire, wildfire smoke, extreme heat), may have similar economic effects on the City. Through the end of 2020, it is estimated that the travel industry on a national level will experience $505 billion in losses, resulting in substantial decreases in federal, state, and local taxes (U.S. Travel Association 2020). Additionally, because the City relies on sales tax revenue to fund maintenance and services, these impacts could, in turn, lead to
changes in the City’s capacity to respond to or mitigate future hazard scenarios. However, it is possible that the current recession is temporary, especially regarding the tourism industry and that the travel economy will continue to lag only until COVID-19 cases decrease, a vaccine is developed and distributed, and travel-related businesses can open at increased capacity (Visit SLO CAL 2020).
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4 REPORT FINDINGS AND NEXT STEPS
This Report sets the stage for the next steps in the Resilient SLO planning process as well as the update to the City’s Safety Element by establishing an understanding of existing hazards, populations, and community assets, and how hazards have historically affected these community assets. Included below are important findings from the summary report.
Flooding
The San Luis Obispo Creek watershed has a long history of flooding, with a series of storms over the last 50 years that have caused millions of dollars’ worth of damage. Damaging flood events have occurred in 1868–1872, 1884, 1897, 1911, 1948, 1952, 1962, 1969, 1973, 1995, 1998, and 2001 (Questa Engineering Corporation 2003; City of San
Luis Obispo 2014).
For the San Luis Obispo Creek watershed, factors that may directly contribute to flooding are infrastructure-induced flow constrictions, wildfire, and degraded riparian corridors (Questa Engineering Corporation 2003).
Post-wildfire runoff represents another risk for flooding because burned areas in the watershed will contribute more runoff and higher sediment loads than vegetated areas.
Extreme Heat and Drought
For this report (see Section 2.3.3 for details), an extreme heat day for the City is defined as a day with a maximum temperature of 89.6°F or above. On average, 4 extreme heat days per year occurred in the City during the historic period (1961–1990). Although the City has not historically experienced many extreme heat conditions, the City
could be experience increased sensitivity to extreme temperatures because residents are not acclimatized to or prepared for extreme heat conditions.
San Luis Obispo County, along with larger areas of California, experience periods of long-term drought that stress the ecosystem and water supplies and, subsequently, impact agriculture, public health, and the economy. The City relies on regional water supplies, the four primary sources including Whale Rock Reservoir, Salinas
Reservoir, Nacimiento Reservoir, and recycled water (City of San Luis Obispo 2019a) and has developed and regularly updates the Urban Water Management Plan to help manage the City’s water supply.
Wildfire and Associated Impacts
The City often experiences high-wind events, such as the Santa Lucia winds, which originate inland and flow westward during the late summer and early fall, counter to the prevailing westerly winds that occur throughout much of the year. The combination of the relatively hot, dry Santa Lucia winds occurring at a time when
vegetation in the County and the City is particularly dry following the summer months can contribute to the ignition and spread of large wildfires.
The risk of wildfires and subsequent impacts to property and life is greatest at the wildland-urban interface (WUI), which is where urban development borders wildland fuels. Wildfire risk is compounded in areas of the WUI that are also located in or near High or Very High Fire Hazard Severity Zones which can be seen in Figure 2-7 in the
Report.
While the City is not at very high risk from the direct impacts of wildfires, the City’s location makes it susceptible
to impacts of wildfire smoke from wildfires in the coastal mountain ranges of central California. Community public health factors that can increase the impacts of wildfire smoke include the prevalence of asthma in children and adults; chronic obstructive pulmonary disease; hypertension; diabetes; obesity; percent of population 65
years of age and older; and indicators of socioeconomic status, including poverty, income, and unemployment.
Sensitive Infrastructure
Critical facilities and infrastructure are instrumental in the City’s ability to respond to hazards that are affected by
climate change. For this reason, they are given special consideration when planning and preparing for hazards so that these critical assets are not damaged and remain operational, especially during emergency events.
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Transportation systems are designed and constructed to withstand certain variabilities in weather and temperature based on observations of historical weather trends for specific climate regions (Li et al. 2011). The performance of transportation assets may begin to decline when the severity of extreme heat periods exceeds
historical ranges, for example, risk of damage to bridges due to thermal expansion increases significantly at temperatures above 100°F (Cambridge Systematics 2015).
The City’s vulnerability to flooding impacts on the transportation system is largely dependent on the capacity of the City’s flood management system to handle large storm events. Impacts on the transportation system from flooding events are generally caused by failures in a City’s stormwater management or flood management system.
Vulnerable Populations and Community Functions
Around 8 percent of occupied households in the City do not have access to at least one automobile, and around 2 percent of occupied housing units have no telephone service available (U.S. Census Bureau 2018), which can both result in increased risk during evacuation scenarios.
Overall, the cost of living in San Luis Obispo is high relative to household income. Approximately 57 percent of renters spend 35 percent or more of their income on rent (U.S. Census Bureau 2018). Those who own homes, in
general, have easier access to equity and provide more flexibility in emergency situations and are, therefore, less likely to become homeless from life events (Brookings Institute 2018).
Approximately 6 percent of the City’s population primarily speaks a language other than English and reports that they are able to speak English less than “very well” (U.S. Census Bureau 2018), which may cause issues with communication during emergency events.
In 2018, the largest employment industries in the City were the educational services industry (15 percent), accommodations and services (15 percent), retail trade (12 percent), and health care and social services (12
percent) (U.S. Census Bureau 2018).
The City is the economic center of the County with many County residents commuting to the City for employment opportunities. Fourteen of the top 25 employers in the County are located in the City (San Luis
Obispo County 2019a).
Tourism is one of the most dominant economic strengths of the City, as demonstrated by the City’s high
employment in retail, arts, entertainment, recreation, and accommodation and food service industries. The City’s tourism sector largely relies on transportation infrastructure, weather, public spaces, the health and abundance of natural resources, and local attractions and services to maintain this vital industry.
In the City’s 2018-19 budget, 25 percent of the City’s revenue came from sale tax while 10 percent came from the transient occupancy tax, generated from visitors staying at the various hotels in the City. As a result, the City relies
heavily on tourism and regional visitors to provide important services to residents including public safety, street paving, bicycle, and pedestrian improvement, and other City services. Given the City’s heavy reliance on the tourism
industry, the City is particularly vulnerable to climate impacts (e.g., wildfire) that would affect this industry.
4.1 NEXT STEPS
The next step in the planning process is to use downscaled global climate projections to evaluate how climate change will affect the City in the near-term, by midcentury, and by late century. A detailed analysis will be conducted to assess how existing hazards may be exacerbated by the effects of climate change and how these exacerbated
hazards may affect the City and its population. Additionally, a Resilience Roundtable will be developed, composed of experts and community stakeholders to inform the planning. These steps will result in the preparation of a full hazards report, which will describe the project activities to date and help inform what resilience strategies should be
included in the City’s Safety Element update to mitigate the current and future impacts of climate change.
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5 REFERENCES
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Questa Engineering Corporation. 2003. Waterway Management Plan. Prepared for the City of San Luis Obispo Department of Public Works and the County of San Luis Obispo Flood Control District – Zone 9.
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The Tribune. 2020a (September). Dolan Fire Grows More Than 3,000 Acres as Highway 1 Cosure Changes. Available: https://www.sanluisobispo.com/article245804290.html Accessed October 24, 2020.
———. 2020b (November). Sales Tax in 5 SLO County Cities Likely to Increase by 1%, Unofficial Election Results Show.
Available: https://www.sanluisobispo.com/news/politics-government/election/article246850357.html Accessed December 4, 2020.
USACE. See U.S. Army Corps of Engineers.
U.S. Army Corps of Engineers, L.A. District. 1974. Floodplain Information: San Luis Obispo Creek and Tributaries Vicinity of San Luis Obispo, San Luis Obispo County, California.
U.S. Bureau of Labor Statistics. Labor Force Statistics from the Current Population Survey: Supplemental data measuring the effects of the coronavirus (COVID-19) pandemic on the labor market. Available:
https://www.bls.gov/cps/effects-of-the-coronavirus-covid-19-pandemic.htm#highlights. Accessed September 16, 2020.
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U.S. Census Bureau. 2018. American Community Survey 5-Year Estimates for City of San Luis Obispo. Available: https://data.census.gov/cedsci/all?q=San%20Luis%20Obispo%20city,%20California&y=2018&d=ACS%205-Year%20Estimates%20Data%20Profiles. Accessed August 24, 2020.
———. 2019. Quick Facts for City of San Luis Obispo. Available: https://www.census.gov/quickfacts/fact/table/sanluisobispocitycalifornia/PST045219. Accessed August 10, 2020.
U.S. Environmental Protection Agency. 2008. Reducing Urban Heat Islands: Compendium of Strategies
US Interagency Council on Homelessness. 2009. The 10-year planning process to end chronic homelessness in your community: A step-by-step guide. Available: https://catalog.hathitrust.org/Record/003867776 Accessed October 24, 2020.
U.S. Travel Association. 2020. COVID-19 Travel Industry Research. Available: https://www.ustravel.org/toolkit/covid-19-
travel-industry-research. Accessed August 23, 2020.
Visit SLO CAL. 2020 (July). This Week in SLO CAL Email. https://mailchi.mp/slocal/this-week-in-slo-cal-2017-06-
110834. Accessed August 23, 2020.
Voelkel, J., D. Hellman, R. Sakuma, and V. Shandas. 2018. Assessing Vulnerability to Urban Heat: A Study of Disproportionate Heat Exposure and Access to Refuge by Socio-Demographic Status in Portland, Oregon. International Journal of Environmental Research and Public Health 15(4):10.3390/ijerph15040640.
World Health Organization. 2020. Rolling updates on coronavirus disease (COVID-19). Available:
https://www.who.int/emergencies/diseases/novel-coronavirus-2019/events-as-they-happen. Accessed August 23, 2020.
Zhu, R., M. S. Wong, É. Guilbert, and P. W. Chan. 2017. Understanding Heat Patterns Produced by Vehicular Flows in Urban Areas. Scientific Reports 7:article number 16309.
Zhu, P., and Y. Zhang. 2008. Demand for Urban Forests in United States Cities. Landscape and Urban Planning 84(3–4):293–300.
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Appendix A
CAL FIRE San Luis Obispo County
Hazard Severity Zone Map
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Appendix B
Resilient SLO Community
Priorities Survey
Prepared by:
Local Government Commission
980 9th St #1700
Sacramento, CA 95814
Authors
Catherine Foster and Amber McGarvey
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1 RESILIENT SLO COMMUNITY PRIORITY SURVEY: RESULTS
SUMMARY
1.1 PURPOSE
Resilient SLO, an initiative of the City of San Luis Obispo, will result in an update to the City’s General Plan to include strategies for building community resilience to the impacts of climate change. The project team consists of the Local
Government Commission as the project managers and Ascent Environmental, Inc. as the lead technical consultant. Resilient SLO is designed to be a comprehensive, innovative, and inclusive planning process – one that elevates
community voice in decision-making, utilizes best-available science and practices, and focuses on the real challenges that individuals face in the city of San Luis Obispo: climate change, the ongoing COVID-19 pandemic, and economic uncertainty. The Community Priority Survey is one means of the inclusive planning process. This survey sought to gather broad input on overall community priorities, concerns related to climate change impacts, experience with past hazards and response efforts, and priorities for local action. Results will be utilized in the short-term to inform the
vulnerability assessment and future community engagement and education activities. Long- term outcomes from the larger Resilient SLO project include educational activities to ensure San Luis Obispo residents and businesses are equipped with the information and strategies to prepare and build resilience to climate change risks and hazards, a
comprehensive vulnerability assessment of the city’s physical assets, and infrastructure, an updated Safety Element of the General Plan with identified adaptation strategies across key sectors, an implementation guide that translates
strategies into detailed work plans and model policies to catalyze action, trainings for City staff and supporting organizations to build collective capacity to respond to climate change hazards and disasters, and an Implementation Guide with work plans and model policies to catalyze action.
1.2 METHODOLOGY
This survey was the first opportunity for community members to give feedback on their concerns related to climate impacts, hazards, and vulnerabilities to be addressed in the larger Resilient SLO initiative. To inform the updates to the hazard mitigation plan and Safety Component of the General Plan, the project team was interested in hearing
from community members on their climate impact experiences and their priorities, in order to incorporate effective planning measures. The climate impacts mentioned in the core questions came from impacts identified for the region in California’s 4th Climate Change Assessment. Other priority areas were sourced from current events and stressors, such as COVID-19. The project team began drafting the survey in July 2020. Team leads on the project from the City, the Local Government Commission, and Ascent Environmental, Inc. met bi-weekly on project deliverables.
1.3 QUESTIONS
The survey consisted of 19 questions, including 13 multiple-choice and 6 open-ended. The survey included 4
demographic questions to evaluate whether respondents reflected the diversity of the local community. Respondents were also asked the zip code of both their residence and employment to gauge whether they lived or worked in the City. The remaining questions evaluated community priorities, concerns over climate hazards and impacts,
experiences with hazards, evaluation of the City’s response to past hazards, and interest in further information on resilience and adaptation topics. The survey opened on August 31st, 2020.
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The scale and categories for each core multiple-choice question are noted below:
Question Scale Categories
Which of the following issues are you currently concerned about? Level of Concern:
Not at all
Somewhat
Very
Access to Healthy Food
Affordable Housing
Air Pollution
COVID-19
Earthquakes
Job Security and Economic Vitality
Social Equity and Justice
Transportation affordability and accessibility
Tree health and maintenance
Water Pollution/ Stream health
Which of the following climate change
impacts are you concerned about? Level of Concern:
Not at all
Somewhat
Very
Drought and Decreased Water Supply
Flooding and Storm Damage
Hotter Temperatures and Heat Waves
Sea Level Rise
Wildfires
Wildfire Smoke
How concerned are you that climate change will impact any of the following areas? Level of Concern
Not at all
Somewhat
Very
Access to Beaches and Open Space
Community Culture
Employment and Job Security
Evacuations
Property Value
Public Health and Safety
Transportation Disruptions
Utility Disruptions and Power Outages
Which of these hazards have you been
personally affected by in the past 1-3 years in
the City of San Luis Obispo?
Level of Impact
Not at all
Somewhat
Significantly
Air Pollution
Drought and Water Supply
Erosion
Extreme Rainfall
Flooding
Hotter Temperatures and Heat Waves
Tule Fog
Wildfires
Wildfire Smoke
For each hazard that you were affected by,
please rank your level of satisfaction with the
City's response.
Level of Satisfaction
Not at all
Somewhat
Very
Air Pollution
Drought and Water Supply
Erosion
Extreme Rainfall
Flooding
Hotter Temperatures and Heat Waves
Tule Fog
Wildfires
Wildfire Smoke
How would you prioritize the following
actions in the city of San Luis Obispo?
Rank Order (1-7) Parks
Public transportation
Housing
Trails
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Question Scale Categories
Space for Businesses
Land Preservation
Agricultural Land Preservation
1.4 DEMOGRAPHIC QUESTIONS
The city sought to reach out to respondents that were representative of the diverse population of the City of San Luis
Obispo. Respondents were given the option of providing key demographic details respondents or declining to answer. The questions included in this section are detailed below:
[Age] What is your age?
Under 18
18 - 24
25 - 34
35 - 44
45 - 54
55 - 64
Above 65
Prefer not to say
[Race/Ethnicity] How would you describe yourself? Please select all that apply.
American Indian or Alaska Native
Asian
Black or African American
Hispanic, Latino, or Spanish origin
Middle Eastern or North African
Native Hawaiian or Other Pacific Islander
White or Caucasian
Other (please specify)
Prefer not to say
[Household Income] What was your total household income before taxes in 2019?
Less than $30,000
$30,000- $39,999
$40,000 - $59,999
$60,000 - $79,999
$80,000 - $99,999
$100,000 or more
Prefer not to say
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1.5 OUTREACH
Original plans for survey outreach included in-person events and in-person survey opportunities to complement online and phone surveys. Due to COVID-19 and quarantine restrictions, these forms of outreach could not take
place; outreach had to be fully remote. The primary form included an online survey on the city’s OpenGov web portal which also regularly hosts surveys for other city initiatives outside this project and for regularly scheduled city meetings that are broadcast on the website. In an effort to bridge the digital divide, the project team worked with the
city to establish a phone line for respondents to call in their responses. However, no respondents utilized the phone line to respond. In-person events would have reached more respondents who do not have internet access but the inability to hold in-person events affected the ability to fulfill that form of engagement.
To promote the phone-line and online survey, the project team reached out over e-mail or social media to organizations, businesses and agencies that serve populations who live, work, or go to school in San Luis Obispo.
These promotional partners were asked to share the survey with their audiences and were given a promotional toolkit with sample email language and social media posts. A wide variety of organizations were contacted (approximately 126), in the hopes of reaching the diverse composition of the local community. Organizations contacted included local educational institutions, non-profits, coalitions, professional associations, cultural organizations, and businesses. Most outreach was conducted by email; 115 organizations were contacted via email. Highly trafficked social media accounts were also contacted. 11 organizations and/or individuals were contacted via social media. Promotional partners received a promotional kit, which included sample e-mail language, sample social media posts plus photo
postcards, and a high level overview of key details, to share with their constituents. The survey deadline, originally the end of September, was extended to October 11th to give more time for responses. Once the deadline was extended, organizations were notified of the extension. In addition to outreach through promotional partners, the survey was
also shared on 1-2 times per week on City’s social media accounts.
On September 17th, a Spanish version of the survey was created on Survey Monkey. On September 29th, the entire
promotional kit was translated to Spanish to conduct more outreach to the Spanish speaking community and shared with promotional contacts. Promotional asks to Latino, Hispanic, and Spanish-speaking cultural groups primarily went through Cal Poly students. Despite reaching out to organizations, the Spanish language survey posted on Survey Monkey did not receive any responses.
1.6 PROCESS OF ANALYSIS
1.6.1 Core Questions
Responses for each multiple-choice core question were analyzed to reveal the following:
a. Areas of Highest Concern/Impact/Satisfaction (for all Respondents)
b. Areas of Highest Concern/Impact/Satisfaction (for key Demographic Groups)
In evaluating the areas of highest concern/impact/satisfaction for all Respondents, we included all relevant measures for the specific category (ex. “Not at all”, “Somewhat”, “Very/ Significantly”). Responses are shown as absolute
numbers (total counts) unless otherwise indicated.
In evaluating the Highest Concern/Impact/Satisfaction for select demographic groups, we chose to only focus on “Very” or “Significant” responses. Although a “somewhat” response indicates some level of
concern/impact/satisfaction (as compared to a “not at all”), it was decided that a “Very” or “Significant” response was more indicative of a respondent’s paramount concern. Thus, all responses for select Demographic Groups represent the percentage or total of respondents indicating “Very or “Significant” for the specific category.
Additionally, further grouping was performed on both Household Income and Race/Ethnicity for the ease of analysis and interpretability.
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Household Income was re-structured into the following three groups:
Less than $50,000
$50,000 - $100,000
$100,000 +
Race/Ethnicity was re-structured into the following two groups:
White or Caucasian
All other Races/Ethnicities
1.6.2 Open-Ended Questions
The survey contained six open-ended questions. Open-ended responses were categorized by topic area and analyzed for emerging themes. A word cloud has also been created to highlight key categories. The full text of
responses will be available in the Appendix.
1.7 RESULTS
1.7.1 Overview
The English version of the survey was initiated on August 31st and closed on October 11th. The English version of the survey had 413 visitors and 331 responses. However, because of duplicate responses, only 328 responses were
included in the analysis. Engagement with the survey generated over 16 hours of public comment. 290 of the respondents indicated that they lived or worked in a City zip code, while 41 responses came from a zip code outside of City limits. All responses, both in-City and out of City zip codes were analyzed. The Spanish Version of the survey,
published two weeks after the English survey, had no respondents. The phone-in option was not utilized either.
1.7.2 Demographics
Respondents were asked to answer basic demographic information including age, housing status, income and ethnicity. These questions were asked to assess how well the survey respondents reflected the actual community make-up of San Luis Obispo. Respondents were asked to identify what 10-year age block they belonged to. The
highest percentage of respondents were 18-24 (26%), followed by 25-34 (16%), 35-44 (17%), above 65 (15%), 45-54 (13%), and 55-64 (13%).
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Half of respondents were homeowners (50%), 44% were renters, and 6% selected “other”.
The most common household income selected by respondents was $100,000-149,000 (58), followed by 200,000 or more (33). In contrast, 30 respondents selected the lowest income bracket (less than 10,000), and 14 selected the second lowest income bracket: $10,000-14,999.
Respondents most commonly described themselves as White or Caucasian (234), followed by Asian (32), Hispanic, Latino or Spanish origin (29), Black or African American (9), American Indian or Alaskan Native (8), and Native Hawaiian or other Pacific Islander (2). It is worth noting that 42 respondents chose “prefer not to say” when
describing their racial identity.
As a reference point, Demographic results from the survey were compared with the 2018 American Community Survey to determine if the survey respondents over or under represented the demographics of SLO residents. Details
on representation are noted below.
Demographic 2018 American Community Survey (%) Community Priority Survey Results (#, %) Over or Under Represented?
Housing Situation
Homeowner 68% 164, 49.5% Under
Renter 35% 146, 44% Over
Age
Under 18 13.1% 0, 0% Under
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Demographic 2018 American Community Survey (%) Community Priority Survey Results (#, %) Over or Under Represented?
18 - 24 34.9% 80, 25% Under
25 - 34 13.6% 51, 16% Over
35 - 44 8.3% 53, 16% Over
45 - 54 8.7% 42, 13% Over
55 - 64 8.9% 40, 12% Over
Above 65 12.5% 46, 14% Over
Ethnicity/Race
American Indian or Alaskan Native .3% 8, 2% Over
Asian 5.6% 31, 9% Over
Black or African American 2.0% 5, 2% Equal
Hispanic, Latino or Spanish origin 18.3% 23, 7% Under
Native Hawaiian or Pacific Islander .1% 2, 1% Over
White or Caucasian 70.7% 237, 72% Over
Other .2% 3, 1% Over
Household Income
Less than $10,000 11.6% 30, 9% Under
$10,000 - $14,999 7.3% 15, 5% Under
$15,000 - $24,999 11.2% 9, 3% Under
$25,000 - $34,999 6.3% 15, 5% Under
$35,000 - $49,999 11.2% 17, 5% Under
$50,000 - $74,999 15.2% 30, 9% Under
$75,000 - $99,999 10.8% 29, 9% Under
$100,000 - $149,999 12.8% 59, 18% Over
$150,000 - $199,999 5.8% 32, 10% Over
$200,000 or more 7.8% 33, 10% Over
Hispanic, Latino or Spanish origin were the most underrepresented when compared to the 2018 American
Community Survey. The survey respondents were also younger than the 2018 American Community Survey results. The two youngest age groups were underrepresented, especially those under 18 whom were not represented at all. All other age groups were slightly overrepresented. 12 respondents chose “prefer not to say” on this demographic
question. Otherwise, all results were within 4 percentage points of the 2018 American Community Survey showing a successful sample of SLO demographics.
The demographic question that most respondents declined to answer was about total household income with 57 choosing “prefer not to say.” The highest three income brackets were overrepresented while lower income brackets were underrepresented compared to the 2018 American Community Survey results. This could be correlated with the
higher percentage of survey respondents in younger age groups, who tend to make less money than older Americans later in their careers.
All respondents had to choose an answer when asked about their housing situations. The options included “Homeowner, Renter, and Other.” Homeowners were under represented by respondents while renters were over represented. 19 chose “Other” to specify their housing situation. Some of them were students living at home or in student housing.
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1.7.3 Open-Ended Questions
Details for each open-ended question are provided below:
Of the open-ended questions, Question 5, “If there are other community issues not listed above that you are
concerned about, please provide them here,” had the most responses (153).
Question 16, “What climate change adaptation and community resilience topics are you interested in learning more about?” had the 2nd highest number of responses (105).
Question 14 garnered the third most responses (95), and asked “Do you have suggestions for how the City of San Luis Obispo can improve response efforts (to hazards)?”
Question 13 had the 4th most respondents (83) and “Do you have any comments to share regarding how you were affected by past hazards and/or city response efforts?”
Question 7, “If there are other climate change impacts not listed above that you are concerned about, please
provide them here,” had 77 responses.
Questions 9 and 11 had the lowest number of respondents (54) and (37) respectively. Question 9 asked for additional areas impacted by climate change of concern. Finally, question 11 asked for additional hazards that respondents have been personally affected by over the past 1-3 years.
Responses to key open-ended questions are discussed in detail in the results below.
There were 604 total responses to open-ended questions.
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1.7.4 Core Questions
WHICH OF THE FOLLOWING ISSUES ARE YOU CURRENTLY CONCERNED ABOUT?
Overall Results
Respondents were most concerned about issues that are affecting their day-to-day life in 2020. As noted on the Figure above, this includes COVID-19, Air Pollution, Job Security, Social Equity and Affordable Housing. The strong concern for COVID-19 is not surprising; during the time period the survey was open, COVID-19 still had California
counties in various stages of quarantine/lockdown. Additionally, the already competitive housing market in the state went through changes as some cities saw rents shift unpredictably. Furthermore, the summer saw high periods of
social unrest as cases of police brutality and racial injustice were brought to the national spotlight. Beginning in August, wildfires broke out across the state following dry conditions, lighting, high-winds, and extreme heat. 2020 has also seen the largest wildfire in California’s history, and the multiple fires occurring caused poor air quality for wide swaths of the state including the central coast.
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Variation by Housing Situation
As noted in the graph above ], renters and homeowners shared a similar amount (+/- 1 - 4%) of concern for a variety of key issues - Water Pollution, Tree Health, COVID-19, Healthy Food, Earthquakes, and Air Pollution. The three areas
of greatest misalignment were Affordable Housing (68% v. 36%); Social Equity and Justice (63% v. 44%); and Transportation Affordability and Accessibility (40% v. 28%). The variation in Affordable Housing is understandable given the status of the respondents as “renters”’; homeowners are likely to be less concerned about housing
affordability due to already owning a home. The variation in Social Equity and Justice is unclear, but could be connected to the age of the respondents (i.e. a correlation between age and homeowner status) or another unifying variable. The same could be said for Transportation Affordability and Accessibility with the added caveat for income.
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Overall, the top three concerns for homeowners are COVID-19 (62%), Water Pollution/Stream Health (48%), and Air Pollution (47%). The top three concerns for renters are Affordable Housing (68%), COVID-19 (65%) and Social Equity and Justice (63%).
Variation by Race/Ethnicity
Level of climate concern between different racial and ethnic groups (in this case, Caucasian v. All other Races/Ethnicities) was fairly uniform on most key issues. The largest divergence occurred for Job Security and Economic Vitality (39% v. 53%); Air Pollution (55% v. 48%); and Transportation Affordability and Accessibility (36% v.
43%). Overall, the top three concerns for White or Caucasian respondents are COVID-19 (66%), Social Equity and Justice (61%) and Affordable Housing (56%). For participants identifying as one or more other races, their top three
concerns are identical with some variation in level of concern (61%; 58%; 57% respectfully).
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Variation by Income Group
Responses by income group are noted in the figure above. There is great variability in the level of concern Individuals
have for key climate and adaptation subjects. The one exception to this observation is a clear concern for COVID-19 across all income groups. Unsurprisingly, individuals within the lowest household income group (“Less than $50,000), expressed a much higher level of concern for Affordable Housing (68% v. 51%, 40% respectfully); Job Security and
Economic Vitality (56% v. 41%, 38%); and Transportation Affordability and Accessibility (46% v. 29%, 27% respectfully). Individuals within the other two income groups ($50,000 - $100,000 and $100,000 +) were more aligned in their levels of concern; the one main exception for this is concern for Water Pollution/ Stream Health (63% v. 42%).
Overall, individuals with a household income of less than $50,000 were most concerned about COVID-19 (71%); Affordable Housing (68%); and Social Equity and Justice (62%). Individuals with a household income between $50,000
- $100,000 were most concerned with Water Pollution/ Stream Health (63%); COVID-19 (61%); and Air Pollution (56%). Individuals with a household income of $100,000 or more were most concerned with COVID-19 (61%); Social Equity
and Justice (52%); and Air Pollution (48%).
Variation by Age
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When evaluated on the dimension of age, individuals expressed some similar concerns. COVID-19 continues to be a trend with the majority (50% +) of individuals expressing a high level of concern. More specifically, individuals above the age of 65 were most concerned with COVID-19 (76%); individuals between the ages of 45 and 54 were the least
concerned with COVID-19 (55%).
Aside from COVID-19, other top concerns included Social Justice and Equity – a first or secondary concern for individuals within the following age groups: 18 - 24; 35 - 44; and 45 - 54. Individuals between the ages of 25 and 34
are also concerned about Social Justice and Equity (56%), but their paramount concern is Affordable Housing (75%). Individuals above the age of 65, on the other hand, are the least concerned about Social Equity and Justice (37%); after COVID-19, they are most concerned about Air Pollution (61%).
Open-Ended Responses
Question: If there are other community issues not listed above that you are concerned about, please provide them here.
Respondents were also able to write in other concerns that were not addressed above. 153 respondents wrote in a concern. The most repeated write-in concern involved homelessness. Selected responses include:
“Homelessness and the lack of focus our city official have on dealing with the issue.”
“How is the community taking care of the House-less population?
What are the options for those that do not have homes during the pandemic and unhealthy air conditions due to
natural disasters (I.e. fires)”
“The growing number of homeless in our downtown open spaces and doorways. Downtown is the heart of SLO
and central to its vibrancy.”
“Homelessness is impacting the waterways & Spot fires. Hard facts to face but true.”
“providing services from homeless and mentally ill persons in the county”
Concerns that were repeated by multiple respondents include issues of police brutality and police funding. Select responses:
“Systemic racism and our bloated county Sheriff’s budget,”
“Racism, police brutality, republican takeover using big money for our local candidates which will diminish the
focus on environmental and justice concerns,”
“Addressing and defunding workplaces and laws that uphold systemic racism. Defund the police in order to allocate funds towards issues like the ones listed above.”
“Overfunding on police--defunding is necessary.”
“I live by Santa Rosa Park and the homeless population is very disrespectful of our property. The creek that runs
through our backyard is littered with their trash and they are constantly stealing things out of our yard. The police are not helpful with the issue whatsoever. The police are an entirely useless organization and are especially terrible here in SLO.”
“Police Department suppressing free speech rights by tear gassing people, over-charging protest organizer, failure to files charges against individuals who drove cars into pedestrians.”
Other concerns that were repeated multiple times include cycling and transportation issues.
Selected responses:
“Walkability”
“Stop wasting money on changing roads to accommodate bike lanes. Instead (sic) focus on adding busses and repairing our streets. Do not take away our street parking to make a bike lane.
“Infrastructure and road building”
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The graphic (shown below) is a word cloud generated from responses the open-end question. As the Word Cloud illustrates, housing and homelessness were two salient topics for respondents.
Which of the following climate change impacts are you concerned about?
Overall Results
Respondents were very concerned about most of these climate impacts. Only Flooding and Storm Damage saw more respondents choosing “Not at all” or “Somewhat”. Wildfires and Wildfire Smoke had the most concern, likely related to the volatile 2020 wildfire season in California that brought that state’s largest wildfire to date and many days of unhealthy air quality.
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Variation by Income Group
When evaluated by income group, all groups, regardless of income, expressed strong concern about Wildfires (80%,
81%, 80% respectfully); however, it is interesting to note that individuals in the lowest income group are more concerned with Wildfire Smoke than Wildfires as a climate category (80% v. 84%). Individuals within the lowest income group are also most concerned about Hotter Temperatures and Heat Waves (78%) and are significantly more
concerned about Sea Level Rise than individuals in other income categories. In comparison, individuals within the highest income group are most concerned about Drought and Decreased Water Supply (76%); their tertiary concern is Wildfire Smoke. Individuals within the middle-income group share similar concerns with some variation in percentage (71% for both).
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Variation by Age Group
When evaluating climate concern by age, a few patterns emerge. Across the board, individuals are most concerned
about Wildfires. Within that category, individuals between the ages of 18 and 24 are most concerned (88%), followed by individuals between the ages of 25 and 34 (86%). There is greater variation when evaluating individual’s secondary concerns. Wildfire smoke is the second highest concern for individuals between the ages of 18 – 24 and 25 – 34. For
all other age groups, their second highest concern is Drought and Decreased Water Supply. The greatest variance in concern among age groups is with Sea Level Rise. Individuals between the ages of 18 and 24 have the highest level of concern (65%), with individuals above the age of 65 expressing the least amount of concern (17%).
Variation by Race/Ethnicity
Climate concerns between different racial and ethnic groups (in this case, Caucasian v. All other Races/Ethnicities) was fairly uniform on a majority of issues (+/- 6%) – Drought and Decreased Water Supply (78% v. 75% respectfully); Hotter Temperatures and Heat Waves (75% v. 73%); Wildfires (84% v. 79%); and Wildfire Smoke (79% v. 73%). The
largest divergences occurred for Flooding and Storm Damage (24% v. 36%) and Sea Level Rise (37% v. 49%). Regardless of racial or ethnic identify, all individuals noted the same top concern: Wildfires. Secondary and tertiary
concern varied slightly – Wildfire Smoke (79%) and Drought and Decreased Water Supply (78%); vs. Drought and Decreased Water Supply (75%), Hotter Temperatures and Heat Waves (73%), and Wildfire Smoke (73%).
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Variation by Housing Situation
Climate concerns among individuals in different housing situations varied slightly. The top concern for Homeowners
and Renters is Wildfire (72% v. 85% respectfully). Secondary concern for these two groups deviated; renters are more concerned about Wildfire Smoke (84%); homeowners are more concerned about Drought and Decreased Water Supply (68%). Individuals identifying their housing situation as “Other” had four competing interests at 79% - Drought
and Decreased Water Supply, Hotter Temperatures and Heat Waves, Wildfires, and Wildfire Smoke. The greatest divergence on level of concern occurred between Homeowners and Renters on the issue of Sea Level Rise: 51% of renters expressed concern versus only 22% of homeowners.
Open-Ended Responses
Question: If there are other climate change impacts not listed above that you are concerned about, please provide them
here.
There were 77 responses to this question. Answers were categorized by topic area. The four most prevalent themes discussed by respondents were:
1) Biodiversity and Health of Inland and Marine Ecosystems
2) impacts to Agriculture & Food Systems
3) Water Supply
4) Social Inequality.
Biodiversity and impacts to wildlife and their habitats were key concerns for respondents. Concerns were raised about
both inland and marine ecosystems. Key concerns for marine ecosystems included plastic pollution and ocean acidification. Respondents were also concerned with the impacts of climatic changes on agriculture and how agricultural changes might impact food supply and access. Water supply was also frequently mentioned. Over half of comments related to water discussed over-building and the impacts of new development on water supply. Comments also mentioned modified agricultural practices, water conservation, use of non-potable water and desalinization as potential solutions. Social inequality was another key issue. Comments in this category mentioned social justice, systemic and environmental racism, environmental justice, issues of representation, impacts to low
income communities, and wealth inequality.
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Subject Area Issue Frequency of Mentions
Environmental impacts
Biodiversity and Health of Inland and Marine Ecosystems 22
Pests and Diseases 4
Negative Environmental Impact of Development 2
Water Water Supply 8
Agriculture Agriculture & Food Systems 11
Human Systems
Social Inequality 7
Economy 4
Public Health 3
Energy & Infrastructure Energy 4
Transportation 4
Natural Disasters
Extreme Weather 5
Mudslides/Mudflows 3
Wildfire or forest management 3
Temperature 2
Other Climate Change is not occurring or should not be addressed by City 6
Responses to the open-ended question were also used to generate a Word Cloud (shown below). The Word Cloud
illustrates the prevalence of words such as water, agriculture, environment, native, wildfire, food, etc. The frequency of these themes indicates that topics related to environment, water and agriculture are common concerns for respondents.
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HOW CONCERNED ARE YOU THAT CLIMATE CHANGE WILL IMPACT ANY OF THE
FOLLOWING AREAS?
Overall Results
Respondents chose “Very Concerned” with less frequency for this question than previous questions. There is high concern about Utility Disruptions and Power Outages which aligns with the context of this survey’s timing. Summer
2020 brought extreme heatwaves in the state and the California Independent System Operator issued multiple “flex warnings” statewide to conserve energy and blackouts occurred as demand for electricity to combat extreme heat increased. Customers in Northern San Luis Obispo county experienced outages in August 2020. Additionally, Pacific
Gas & Electric has also participated in Public Safety Power Shutoffs as a wildfire prevention tool that also created utility disruptions. High concern around Employment and Job Security and Evacuations also fits trends seen in earlier
questions and align with later concerns about Wildfires and Wildfire Smoke.
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Variation by Income Group
As noted on the graph above, regardless of income, all individuals expressed the highest level of concern for Public Health and Safety (70%, 64%, 60% respectfully). Secondary concern varied slightly. After Public Health and Safety, individuals with household incomes of less than $50,000 or more than $100,000 were most concerned with Utility Disruptions and Power Outages. In comparison, individuals in the middle-income group ($50,000 - $100,000) had a
secondary concern of Evacuations. The greatest divergence in level of concern occurred between individuals with a household income of less than $50,000 and more than $100,000 on the issue of Transportation Disruptions. Individuals within the lower income group had the highest level of concern among the three groups for this category
- 42%. On the other end of the spectrum, the opposite was true: individuals within the highest income group had the lowest amount of concern – 14%.
Variation by Age Group
When viewing concern for climate change impacts by age, a few patterns emerge. Across the board, individuals are most concerned about climate’s potential impact on Public Health and Safety. Within that category, individuals between the ages of 18 and 24 are most concerned (75%), followed by individuals between the ages of 25 and 34 (73%). Utility Disruptions and Power Outages are also a common concern among the age groups, with at least 50%
of individuals in five age groups (all except individuals between the ages of 55 and 64) expressing concern.
Omitting Public Health and Safety, individuals between the ages of 18 and 24 are most concerned about climate’s potential impact on Evacuations (66%); and Utility Disruptions and Power Outages (61%). Individuals between the
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ages of 25 and 34 are also concerned about the same two categories with some variation in level of concern (57% and 69% respectfully). Individuals between the ages of 35 and 44 share a similar level of concern for Utility Disruptions and Power Outages (57%); they are also concerned about Access to Beaches and Open Space (42%).
Individuals between the ages of 45 and 54 are concerned about Utility Disruptions and Power Outages (50%), followed by Evacuations (29%). Individuals between the ages of 55 and 64 are also concerned about Utility Disruptions and Power Outages (48%), in addition to Evacuations (33%). Finally, individuals above the age of 65 are
concerned about Utility Disruptions and Power Outages (50%) and Evacuations (37%).
Variation in Race/Ethnicity
Regardless of racial or ethnic identify, individuals expressed similar levels of concern for two potential climate change impacts: Public Health and Safety (69% v. 64%, respectfully) and Utility Disruptions and Power Outages (56% v. 67% respectfully). Tertiary concerns were also the same – Evacuations (49% for both). The greatest divergence between groups occurred for Transportation Disruptions; only 24% of White or Caucasian respondents expressed concern
compared with 42% of respondents of respondents identifying as all other races and ethnicities.
Variation by Housing Situation
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When viewed through a housing situation lens, a few patterns emerge. Despite the variability, all respondents regardless of housing situation are concerned about Public Health and Safety, with individuals in the “Other” category reporting the highest level of concern at 79%. This same group expresses the same level of concern for Evacuations.
Both renters and homeowners also list Utility Disruptions and Power Outages as a secondary concern (50% and 67% respectfully). This is a tertiary concern for individuals in “Other” alongside Transportation Disruptions. In terms of priority, homeowners and renters share a similar view on their concern for Evacuations (37% v. 59% respectfully). Of
all the questions so far, this answer elicited the highest level of variability in level of concern; the smallest variation among levels of concern is for Utility Disruptions and Power Outages at 4%.
Open-Ended Responses
Question: If there are other areas impacted by climate change not listed above that you are concerned about, please provide them here
Respondents were also able to write in other concerns that were not addressed above. 54 respondents wrote in a concern.
6 of the respondents brought up concerns over how marginalized communities would feel climate impacts first.
Selected responses:
“I am concerned about how climate change will impact low income communities and communities of color first.”
“Health effects upon the poor and elderly, especially during the summer.”
“We need a community plan to support frail elders and people with chronic illness who are reliant on electricity, and cannot be without power. Example: people w/ lung disease, who use oxygen, electric beds, breathing assist
machines. The rolling blackouts that are happening in CA (due to fire and maxing out of the power grid) are devastating for this portion of our community. We need an organized, local government plan to identify and
support these folks.”
8 Respondents brought up concerns about biodiversity, natural resources, and wildlife. Selected responses:
“Access to food and use of agricultural resources, impacts to marine life and fisheries (including for food)”
“Again, that we are not considering the impact on local wildlife” or preparing to create safe zones for animals
(inland & marine)
“Natural resource conservation is being impacted by the lack of regional consensus about conservation and habitat restoration goals as the climate changes. SLO has an opportunity to build on leadership and successes
from within City government to emphasize natural resource conservation measures in a changing climate.”
“Loss of biodiversity, climate refugees, natural resources”
8 Respondents brought up concerns about agriculture and/or local food access:
“Weather patterns, heat waves, and quality of air and water affecting the ability to grow food.”
“crop yield and tourism”
Remaining responses ranged from denying the city’s role in responding to climate change, concerns over utilities or utility shut offs, concerns over evacuations, from where evacuees can go to how to handle refugees coming to the
SLO region. A few respondents brought up concern for “hope” in the future.
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Open-ended responses were used to generate a Word Cloud (shown below). The words shown were frequently used by respondents.
WHICH OF THESE HAZARDS HAVE YOU BEEN PERSONALLY AFFECTED
BY IN THE LAST 1-3 YEARS IN THE CITY OF SLO?
Overall Results
This question has more respondents reporting they have not been personally affected by about half of these impacts in the last 1-3 years. The most significantly reported impacts were of Wildfire Smoke, Hotter Temperatures and Heat
Waves, and Air Pollution which matches the trends in other questions and references the context of events in 2020 (i.e. wildfire and extreme events). Even when wildfires do not occur in the city boundaries, impacts of wildfire smoke and air pollution affect many residents somewhat or significantly which explains why “Wildfire” has less significant
direct impact for respondents than “Air Pollution” and “Wildfire Smoke.’
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Variation by Age Group
In terms of Hazards, all age groups have been quite impacted by Wildfire Smoke and Hotter Temperatures and Heat Waves. Within these two categories, individuals between the ages of 25 and 34 were most impacted (61% and 57%, respectfully). Individuals above the age of 65 indicate the lowest level of impact for these two categories (46% and
37%, respectfully). Other impactful hazards include Wildfires - with individuals between the ages of 25 and 34 reporting the highest level of impact at 29%, followed by individuals between that ages of 35 and 44 at 26% - and Air Pollution – with individuals between 25-34 and 55-64 each expressing the highest impact – at 33%. Erosion, Extreme
Rainfall, Flooding, and Tule Fog were very rarely listed as a high impact for individuals across the age groups.
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Variation by Race/Ethnicity
In terms of racial and/or ethnic identity, all groups expressed a high level of impact for Wildfire Smoke (59% and 53% respectfully) and for Hotter Temperatures and Heat Waves (52% for both). A tertiary concern was Air Pollution (34% and 29%). Similar to the other analyses for this question, respondents did not express high levels of impact for Erosion, Flooding, Extreme Rainfall or Tule Fog. The greatest divergence between groups occurred for Drought and
Water Supply; Caucasian or White respondents reported a higher level of impact – at 18% - than individuals of other races/ethnicities – at 10%.
Variation by Income Group
From an income perspective, individuals within the lower income bracket were most impacted by Hotter Temperatures and Heat Waves (58%), followed by Wildfire Smoke (53%). Individuals in the other two categories expressed a similar level of impact for Hotter Temperatures and Heat Waves (46% and 44% respectfully), with a
higher level of impact for Wildfire Smoke (63% and 50%). In fact, individuals in the middle-income group express the highest level of impact for Wildfire Smoke. Other shared impacts include Air Pollution (35%, 27%, and 29%
respectfully) and Wildfires (24%, 25% and 17%).
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Variation by Housing Situation
Homeowners, renters, and individuals indicating “Other” report being most impacted by Wildfire Smoke (45%, 60%, and 58%, respectfully), followed by Hotter Temperatures and Heat Waves (41%, 55%, and 47%, respectfully). Aside from these two categories, renter and homeowners report being more impacted by Air Pollution than Wildfires (26% v. 36%; 15% v. 26%); individuals indicating “Other” report the opposite (26% v. 32%).
Open-Ended Responses
Question: If there are other hazards that you have been personally affected by in the past 1-3 years in the City that are not listed above, please provide them here.
There were 37 responses to this question. Of those responses, 10 discussed climate related hazards. The remaining 27
discussed other community issues not directly applicable to climate change. Related responses discussed the following:
Mortality of trees that were weakened by drought. Tree caused damage to the home and increased cost of air conditioning due to loss of canopy.
Extreme 116 degree heat
Nearby wildfires and the impacts of smoke on an asthmatic
Experience with Lyme Disease
Landslide from extreme rainfall
Air pollution that lead to the development of asthma
Dust
Power outages
Invasive species
Loss of biodiversity affecting people psychologically and economically.
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Responses to question 11 were used to generate a Word Cloud (see below).
FOR EACH HAZARD THAT YOU WERE AFFECTED BY, PLEASE RANK YOUR LEVEL
OF SATISFACTION WITH THE CITY’S RESPONSE.
Overall Results
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Open-Ended Responses
Question: Do you have any comments to share regarding how you were affected by past hazards and/or city response efforts? Please describe specific hazard, location, and response
Write-in answers to this question demonstrate that respondents are either not clear on how much the city can do in responding to climate impacts, don’t believe the city can respond to impacts that they few as “natural” or at the
state/federal scale or they do not know how the city responded and wish for more publicity about city response efforts. Because of these frequently cited opinions, multiple respondents indicated they used “Not at all satisfied” to indicate “not applicable” or they skipped responding at all. For these reasons, write-in responses are a more useful
analysis than the absolute numbers. 83 respondents wrote in a short answer.
Select responses that express doubt or confusion about the city’s ability to respond:
“Several of the above items are caused by nature and the city can’t do anything about them so they should not even have been included.”
“I cannot see how the city could do anything about fires, floods, fog and rain. The city can and should focus on
eliminating trash and waste in our local parks and waterways. That will have a huge impact on its citizens' outlook on our government taking care of the city.”
“Let's act now to reduce the burnable debris around out (sic) homes and stream beds.”
“I don’t think the city can do anything to control or improve these items except for provide infrastructure that
allows emergency responders to quickly and safely access the entire population. In that regard the city has actively made response times and access to core populations worse by converting roadways to bicycle paths and failing to add lanes to major thoroughfares. I think the city really needs to reassess its willingness to sacrifice
human lives in the name of environmentalist ideals. When someone has a stroke every minute of delay in transport to the hospital costs that person brain function and treatment options. Additionally these alternative modes of transportation have no ability to help facilitate business growth or commerce, and as such provide no return on the funds the city invests in them.”
“I really don't see how the City can "respond" to some of these. Air pollution from what? If wildfires, not much the City can do apart from abatement and building codes already in place. Auto pollution is minimal. And City Hall cannot dictate the weather.”
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“I'm not aware of the City's response to any of the above listed items except to say the more growth, housing, etc. that occurs the more air pollution and lack of water supply will be factors in everyday life. As well as infrastructure that cannot support the housing growth all around the city.”
“I used "Not at all satisfied" to indicate more of "not applicable" Air pollution is being worked upon by the City, and awareness of the need for conservation of water was an ad campaign and a hotline, both appreciated. The effects of the others I cannot see the City's responsibility to. In my case only.”
“I only rated a few factors because many of these issues are not truly under local influence/control. The City has done a good job addressing our flood control system. More needs to be done about wildfire prevention but a
significant challenge is the amount of overgrown vegetation on private property or land just outside the City's footprint.”
“In general, I feel the city hasn't really acknowledged it's general resident experiences with climate change. Too much focus on bike lanes and ignoring the less glamorous/ youth-focused, and middle/upper class side of being impacted by climate change.”
“I'm not sure how to respond to some of these questions where I do not have a direct experience, and as a result don't have a level of satisfaction to report. I believe the City leadership's push for climate action, sustainable
transportation, affordable housing, and protection of open space are all in the right direction.”
“You should have had a "not applicable" column. There is little the City can do about hot temperatures or wildfire smoke drifting into the area. Drought and water supply is something the City can control. Constantly raising
water rates while allowing hundreds of new homes it NOT the way to respond.”
“What is the city doing for any of these? If they are doing something, they sure aren't doing a good job publicizing what they are doing.”
Select responses that offer more concrete feedback:
“Storm drain clearance especially on the north end of the city near Loomis Street is sometimes lacking and more frequent patrols by city personnel to this area would be appreciated.”
“Appreciate the notifications we get through Twitter and other platforms.”
“Address fire prevention like the Native Americans and how we used to. Prevent forest fires.”
“City could do more to reduce water use - encourage lawn reduction, including on City properties.”
“The city has used a wide brush to paint very high fire hazard and should be more specific/precise in classifying fire hazard. A city perimeter approach would be more effective and appropriate. Over-classifying can have dire effects on residents ability to obtain fire insurance. Just like keeping areas in flood zones that have been
mitigated is a problem.”
“The potential for water shortage is ignored when the city approved extensive new housing. Otherwise these developments would have been disapproved. The city says one thing but does another with respect to this topic.”
“While the firefighters have indeed been heroes in this scenario, the city need to undertake extreme conservation
measures, plant more trees to increase air quality, install solar throughout the town, enforce xeriscaping and the like. I do appreciate the city/county air report.”
“Stonewalling on the Lake Dredging project is unacceptable.”
“Keep beaches open for locals during heat waves.”
‘I actually was not aware of the City's response at all to any of these issues.”
“Last winter when highway 5 was closed due to snow. The freeways and highways were blocked for HOURS and HOURS because we only have one or two routes to use in Southern California and the Central Coast.”
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“What is the city doing to capture and utilize the very little rain we get each year? How much of it are we losing to runoff in our ocean? What is the city doing to implement a carbon free grid by 2030? How can we take wisdom and advice from our local indigenous people to better understand working with the environment?”
“My property is located within a flood zone. Mitigations, such as creek debris clearance, have been successful (so far!). Though many residential neighborhoods back up to steep, somewhat denuded hills, there have not been any significant mudflows (so far!). There is an inadequate supply of N95 masks which are necessary when doing
errands during periods of hazardous air quality.”
“Allowing 75 foot buildings downtown adds to the heat zone of the downtown corridor”
“I'm glad a notice has been put out about the air pollution hazards. We need strong messaging from our leadership to help us through challenges.”
“heat mitigation in low income housing is not being taken seriously.”
“I do not think, in a town where the majority do not have AC, we (the city) are ready for extreme heat.”
“It wasn't apparent to me that the homeless had options to shelter in a cool/clear air space”
“Hotter temperatures, but the city does not have shade structures in many areas.”
“Flooding. If we and our neighbors didn't go out and clean the storm drains when it rains hard, multiple yards
would be underwater.”
“Wildfires: Reverse 911 works really well but most of my friends didn't know about it so trying to get the word out
better. The Reverse 911 message also needs to be more clear including identifying the threat.”
Responses to this question were used to generate a word cloud (see below).
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HOW WOULD YOU PRIORITIZE THE FOLLOWING ACTIONS IN THE CITY OF SLO?
Respondents were asked to prioritize actions in the City of San Luis Obispo. Housing was most frequently listed as a
number one priority; housing was chosen as the top priority 122 times or by 40% of respondents. Land Preservation, another priority topic, was selected as the number one priority 89 times or by 30% of respondents. Selected as the number one priority less frequently were Agricultural Land Preservation (selected 29 times or by 10% or respondents),
Public Transportation (21 times or 7%), Trails (16 times or 5%), Parks (14 times or 5%), and Space for Business (9 times or 3%).
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WHAT CLIMATE CHANGE ADAPTATION AND COMMUNITY RESILIENCE TOPICS ARE
YOU INTERESTED IN LEARNING MORE ABOUT?
There were 104 responses to this question. The most common topical areas mentioned by respondents were transportation, energy, and the environment. Water, wildfire, housing and social issues were also prevalent topics, in
addition to agriculture, temperature changes, development, and emergency management. Issues related to climate change mitigation, waste and pollution and the economy were also mentioned. Multiple comments indicated interest in any topic related to climate adaptation and resilience. There were also several comments that the City should not
be pursuing this topic. The table below summarized the approximate number of mentions for each topical area and topics suggested by respondents.
Topical Area Topics Mentions
Transportation Electric vehicles and charging
Public transportation
EV charging for apartment renters
Active Transportation/bikeability/walkability
Reducing emissions from transportation
Traffic reduction
Walkable neighborhoods with access to services
Pro Con approach to transportation decisions
19
Energy Solar, wind and renewable energy sources
Solar for residential & existing homes
Require rooftop solar
Microgrids, batteries, & energy reliability
Affordable energy
Alternate technology such as trash to energy
Preventing early close of Diablo Canyon
Eradication of gas burning engines
15
Environmental
Protection Open Space/land preservation
Wildlife conservation
Air pollution
Urban forestry and trees to for urban cooling and societal benefits
Ecosystem-based adaptation
Saving beaches
Natural landscaping
15
Water Water conservation
“Integrated water resource management (intersections of flood management, water supply, watershed/habitat/GW protection, and water quality protection).”
Drought and water supply
Increasing infiltration
Community outreach on water conservation
11
Wildfire City wildfire mitigation efforts
Fire prevention & planning
Outreach to property owners at the wildland urban interface
Native land management practices and knowledge
10
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Topical Area Topics Mentions
Fire safe building
Wildfire smoke
Prescribed burns
Fire response
Housing Balancing housing needs with land preservation
Affordable housing
Tiny homes
Housing for Cal Poly students
Repurposing existing developed land for housing
Off-grid housing
How climate change will impact housing prices
9
Social Issues How can the City encourage residents to contribute more?
Homelessness
Mass migration into City
How can the City avoid an increase in the wealth gap and unequal burden of climate change on marginalized communities?
Social equity and justice
Community outreach regarding personal actions such as water conservation, wildfire mitigation, carbon footprint reduction, etc.
How can the government better understand community wants and needs?
Covid-19
9
Agriculture Community gardens
Healthy food access
Local food
Soil health
Regenerative agriculture and permaculture
7
Temperature Changes Extreme heat leading to AC installation and impacts on grid
AC for schools and senior centers
Alternatives to AC
7
Development How can we accommodate growth in a less dense format?
Environmentally friendly development/ how can growth contribute to resilience?
Encouraging businesses and government to be environmentally conscious
Analysis of environmentally damaging industries and promoting more sustainable industrial practices
Resilient construction materials and landscaping
5
Emergency Management Faster warning systems for natural disasters
Planning for compound hazards
Pandemic and epidemic planning
Disaster preparedness and planning
Neighborhood resilience
Resilience
5
Climate Change Action City efforts to plan for and combat climate change 4
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Topical Area Topics Mentions
Transitioning to a fossil fuel free society
Waste & Pollution Waste in parks and open spaces
Recycling and composting programs
Compost use in community gardens
Noise and light pollution
3
Economy Job security
Diversifying employment from tourism
2
Responses to this were also used to generate a Word Cloud. As the Word Cloud highlights, water, transportation, energy, housing and land were among the frequently used words.
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Appendix E Environmental Justice and Disadvantaged Communities
The City is home to populations with sociodemographic characteristics that may have a
higher vulnerability to climate impacts. These groups may be concentrated in key areas
of the City and have the potential to overlap with key climate related hazards that place
these populations at a disproportionate higher risk from climate impacts. In general, low-
income residents, communities of color, tribal nations, and immigrant communities have
disproportionately experienced some of the greatest environmental burdens and re lated
health problems throughout the history of the U.S. and in California.
These historic inequities are, in the majority of cases, not a coincidence but a result of
inappropriate zoning and negligent land use planning, intersecting structural inequalities,
failure to enforce proper zoning or conduct regular inspections, deed restrictions and
other discriminatory housing and lending practices, limited political and economic power
among certain demographics, the prioritization of business interests over pu blic health,
development patterns that tend to concentrate pollution and environmental hazards in
certain communities, and the placement of economic and environmental benefits in areas
outside of disadvantaged communities (California Environmental Justice Alliance 2017).
Based on the State’s definition of disadvantaged communities, no census tracts within
the San Luis Obispo region are designated as disadvantaged communities. However, the
San Luis Obispo Council of Governments (SLOCOG) has created a regiona l definition of
disadvantaged communities to help distribute funds more equitably, and meet the state
and federal environmental justice requirements. In the San Luis Obispo Region,
disadvantaged communities are defined as disproportionately burdened areas that are
economically distressed and/or historically underrepresented as a part of the local
government process. The Disadvantaged Communities Assessment identifies 13
variables that address a wide range of socioeconomic and population -based factors to
geographically define these disproportionately-burdened areas. The 13 variables are:
1. Racial Minority
2. Ethnic Minority
3. Disability Status
4. Household Income
5. Free or Reduced-Price Meals
6. Educational Attainment
7. Language Proficiency
8. Renter Affordability
9. Housing Ownership Affordability
10. Older Adults: Age 75 Years and Older
11. Youth: Age 15 Years and Under
12. Households with No Vehicle Available
13. Households with No Computing Device Available
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SLOCOG completed analysis at the traffic analysis zone (TAZ) level using these variables
and evaluated relative to state and county averages. Points were assigned accordingly
for each variable, and a composite score was derived for each TAZ in the region. The top
quintile (top 20 percent) of TAZs were considered meeting the regional definitio n of
disadvantaged communities. Individuals or households that include one or more of these
variables are considered more vulnerable to natural and manmade hazards as well as
the local impacts of climate change.
ENVIRONMENTAL JUSTICE SURVEY RESULTS
In preparation for development of the Community Safety and Resilience Element, an
Environmental Justice Survey for community organizations was conducted to gather input
on environmental topics from organizations that serve vulnerable and/or disadvantaged
communities in the city. The survey gathered input on how the city can better support
disadvantaged communities by reducing environmental pollution, identifying key
community needs, and increasing the voice of marginalized groups in the City's decision-
making process. Highlights from the survey are included below and have been integrated
into the environmental justice goals, policies, in programs in this element. The full survey
results can be found in Appendix D.
The survey was sent via email to 59 staff members at local organizations or agencies that
work with disadvantaged communities or focus on diversity, equity, and inclusion. The
survey received seven responses from community organizations that serve populations
that live, work, and/or go to school in the city and in San Luis Obispo County.
Survey respondents noted the following types of environmental pollutants adversely
impacting vulnerable populations:
1. Exhaust and traffic pollution from living in proximity to major roadways
2. Contaminated drinking water
3. Lead paint or pipes in housing
4. Pesticide pollution from agriculture
5. Living/working near environmental clean-up sites
6. Smoke from wildfires
Survey respondents included the following recommendations for how the City can help
protect vulnerable populations from environmental pollutants, hazards and climate
change impacts:
7. Host listening sessions inside of affected communities
8. Devote new human and material resources to investigate and remedy environmental
injustices
9. Identify and appoint leadership from within the affected communities
10. Provide monetary or other basic needs support to farmworkers when their work is
disrupted by unusual or dramatic climate events
11. Incorporate greater city plans to clean up pollutants and test for pollutants in soil and
other locations
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12. Provide access to resources, education, funding, and create platforms or events where
community members may share their experiences and be intentionally listened to
Community Resilience and Social Infrastructure
Adaptive capacity is defined as the ability of systems, institutions, humans, and other
organisms to adjust to potential damage, to take advantage of opportunities, or to respond
to consequences (IPCC 2014). Alongside the steps the City and partner agencies have
already taken to protect the City from existing climate-related hazards and increase its
adaptive capacity, it is important to recognize the role community organizations and
informal social networks can play in building adaptive capacity to the impacts of climate
change.
Social cohesion, generally understood as the extent of connectedness and solidarity
among groups in society or community, is one of the strongest indicators of resilience
during disaster events as well as in post-disaster recovery efforts (Townshend et al.
2015). Social cohesion can play an important role in helping protect residents, particularly
vulnerable populations, during climate-related disasters.
Important indicators of social cohesion identified in this research include:
1. Belonging versus isolation, which means shared values, identity, feelings of
commitment;
2. Inclusion versus exclusion, which concerns equal opportunities of access;
3. Participation versus non-involvement;
4. Recognition versus rejection, which addresses the issue of respecting and tolerating
differences in a pluralist society; and,
5. Legitimacy versus illegitimacy (Jenson 1998).
An important component in remaining resilient to the impacts of climate change and
climate-related disasters is the post-disaster recovery period. As noted in research on the
topic, a focus not only of the physical rehabilitation of the built environment but on
addressing the emotional and mental health impacts of disasters is needed to ensure a
successful community recovery during the post-disaster period. The emotional and
mental health impacts of disasters can be addressed through various types of social
cohesion including social and support networks (including access to social support in
times of need), social participation (as the obverse of social isolation and being cut off
from relationships providing friendship and company), and community engagement
(including volunteering which draws people together to work for the benefit of others)
(Townshend et al. 2015). While measuring the degree of social cohesion present in the
city is not possible at this point, this subject is discussed here to emphasize the
importance of social cohesion in increasing community resilience to the impacts of the
climate change. Social cohesion here is highlighted as important component of
community-based adaptative capacity and is discussed, as appropriate, in the
discussions on specific climate-related hazards.
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COMMUNITY ASSETS SURVEY RESULTS
In preparation for development of the Community Safety and Resilience Element, and
Community Assets Survey was conducted to gather input from the general public about
social cohesion, community strengths, and disaster preparedness. Survey respondents
were asked which community assets and resources were most important to them under
four different scenarios: Normal Life, Disaster Preparation, During a Disaster Event, and
during Post Disaster recovery. The survey was open from August 12 through August 30,
2021. There were 266 responses to the survey. Highlights from the survey are included
below and have been integrated into the goals, polices, in programs in this element. The
full survey results can be found in Appendix D.
Community Strengths: Across all four scenarios, these assets were frequently
mentioned:
1. Public Information (Disaster Information, Social Media, News)
a. 47 mentions accounting for 20% of responses
2. Medical/Emergency Services (Public Safety)
a. 41 mentions accounting for 17% of responses
3. Open Space/Trails
a. 31 mentions accounting for 13% of responses
Respondents listed receiving the following benefits from the assets listed above:
Public Information: (Disaster Information, Social Media, News)
6. Access to accurate and understandable information
7. Informs about the current state of situation
8. Enhances ability to prepare and mobilize
9. Provides direction and recommendation
10. Connects community members to resources
Medical/Emergency Services:
11. Vaccines, injuries, aid
12. Provides reassurance and “peace of mind” when services are well staffed, present, and
equipped
Open Space/Trails:
13. Improves mental and physical health
14. Outlet for activity or relaxation
15. Overall fitness and wellbeing are supported
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Overview:
The Environmental Justice Survey for Community Organizations was intended to gather input on
environmental topics from organizations that serve vulnerable and/or disadvantaged
communities in the City of San Luis Obispo. More specifically, the survey gathered input on how
the city can better support disadvantaged communities by reducing environmental pollution,
identifying key community needs, and increasing the voice of marginalized groups in the City's
decision-making process. The survey findings will support the integration of environmental
justice into the City’s General Plan Safety and Community Resilience Element.
The survey was open for two weeks from August 12th, 2021 to August 26th 2021. The survey was
sent via email to 59 staff members at local organizations or agencies that work with
disadvantaged communities or focus on diversity, equity, and inclusion. The survey was also
shared with participants of the Environmental Justice Working Group.
Participation:
The survey received 7 responses from the following organizations:
• Diversity Coalition San Luis Obispo County
• SLO Food Bank
• HASLO
• United Way of San Luis Obispo County
• Lumina Alliance
• CAPSLO
• Habitat for Humanity SLO County
Populations Served:
All respondents indicated that they serve populations that live, work, and/or go to school in the City
of San Luis Obispo. All organizations reported that they serve low-income, non/limited English
speakers. Also, all organizations serve young children and youth within SLO. The majority (6/7) of
responses showed to support those who are unhoused, unemployed, and uninsured. People without
vehicle access, undocumented individuals and families, people with disabilities, and outdoor workers
are also served by a majority of organizations. About half of respondents show support for people
with chronic health conditions and people with severe mental illness.
Only one organization (Diversity Coalition SLO County) indicated that they aid racial and ethnic
people of color and faith-based communities, this same organization specifically supports BIPOC
populations. One individual organization described that they serve “low income residents of SLO
County who lack the resources to purchase or obtain enough food for themselves or their families”
while another organization noted they assist those with affordable housing ownership. One other
organization serves victims of violence particularly.
Environmental Pollutants Adversely Impacting Vulnerable Populations
Types of environmental pollutants (all listed frequently among the respondents)
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• Exhaust and traffic pollution from living in proximity to major roadways
• Contaminated drinking water
• Lead paint or pipes in housing
• Pesticide pollution from agriculture
• Living/working near environmental clean-up sites
• Smoke from wildfires
Populations are affected mostly by living and working near the environmental pollutants listed.
Farmworkers are at risk to greater pesticide exposure and are also impacted more by wildfire smoke
as they are working outdoors.
Low income housing are often based in areas that are more impacted by pollutants such as noise
and exhaust from higher traffic volumes.
Due to insufficient resources and low level priorities from local governments, vulnerable populations
are subject to substandard living conditions, lack of proper education/recognition, and are of a low
priority for remediation.
Recommendations for how the City can Help Protect Vulnerable Populations from
Environmental Pollutants, Hazards and Climate Change Impacts
• Host listening sessions inside of affected communities.
• Devote new human and material resources to investigate and remedy environmental
injustices.
• Identify and appoint leadership from within the affected communities
• Provide monetary or other basic needs support to farmworkers when their work is disrupted
by unusual or dramatic climate events
• Incorporate greater city plans to clean up pollutants and test for pollutants in soil and other
locations
• Provide access to resources, education, funding, and create platforms/events where
community members may share their experiences and be intentionally listened to
Community Improvements to Protect the Wellbeing and Safety of Vulnerable Populations
1. Better transit services (more routes, more stops, shorter wait times).
2. Low income housing.
3.
• Cooling Centers.
• Broadband access.
• Cooling/heating for homes and apartments (air conditioning/heat pumps).
4.
• Park access.
• Address food deserts by providing farmers markets and such in low income areas.
• Street Trees.
• Translation Services.
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• Safe parking/ camping areas for the unhoused population that includes services and
resources.
• Community gathering places.
“Real, tangible short and long-term, result driven solutions that are not based in politically motivated
rhetoric and empty promises”
A general consensus shows these needs are anticipated to change beside one organization which
does not think community needs will change as impacts increase. It was noted that better public
transportation and cooling centers will rise in importance. Additionally, heightened rates of
demographic change will increase need for affordable housing, educational resources, and access to
broadband.
Important Public Services and Amenities
• Access to safe living conditions, legal services, and affordable child care.
• Libraries, bus transit, bicycling paths, safe overnight parking, public bathrooms, programs
specifically targeted towards low-income housing.
• Living wage jobs and access to affordable housing.
• Access to public parks and recreation
• Transit improvements for senior and disabled populations.
Specifically for disaster situations
• Cooling centers, clean and safe shelters
• Access to food, clean water, electricity, and transportation
• Translation services and assistance for those with mobility issues
• Temporary housing for displaced individuals
Healthy Food Access
• Increase support for food banks
o Partner with SLO Food Bank to determine regional gaps in service.
o Create opportunities for food distributions, pantries, free farmer’s markets in
underserved communities.
• Improve public transportation to super markets and farmers markets
• Support food banks, farms, and gardens for low income neighbors
Participation in the Public Decision-Making Process
Barriers
• Language barriers seem to be most prevalent.
• Lack of trust also drives participation downward.
• Don’t hear about opportunities (e.g not well connected to the City communication channels)
• Seems to be inaccessible to many people:
o Too little time to engage ( when struggling to put food on table, dealing with
violence, engagement in public government not on radar.
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o Inaccessible meeting times
• Disconnection between members of the public and government body
o Topics of city meeting not relevant
o Lack of interest
o Lack of knowledge on government processes.
Recommendations for improved involvement and communications
• Ensure affected communities have opportunities to create agendas, not simply respond to
agendas.
• Incentivize participation
• Consider alternative meeting times outside of work week/hours
• Collaborate with trusted partners/agencies within different communities to spread
information (specific recommendation to use CAPSLO to disseminate info of interest to
civilians.
• “Prioritize and focus on real life, basic needs that enhance and sustain”
Additional Comments
- “Further reduce jobs/housing imbalance in order to reduce job commute times and all things
associated with them (reduced air quality, decreased quality of life etc.)
- Please sustain our work making environmental justice a core priority in the city’s service to all
its citizens, don’t allow to fall between the cracks... Thank you.
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Appendix A
CAL FIRE San Luis Obispo County
Hazard Severity Zone Map
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Ascent Environmental
Baseline Conditions Report City of San Luis Obispo A-1
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17.78.010
17.78.020
17.78.030
17.78.040
17.78.050
17.78.060
Chapter 17.78
FLOOD DAMAGE PREVENTION
Sections:
Statutory authorization, findings of fact, purpose, and methods.
Definitions.
General provisions.
Administration.
Provisions for flood hazard reduction.
Variance procedure for floodplains.
17.78.010 Statutory authorization, findings of fact, purpose, and methods.
A. Statutory Authorization. The Legislature of the State has in Government Code Sections 65302, 65560, and
65800 conferred upon local governments the authority to adopt regulations designed to promote the public
health, safety, and general welfare of its citizenry. Therefore, the council does hereby adopt these floodplain
management regulations.
B. Findings of Fact.
1. The flood hazard areas of the city are subject to periodic inundation, which results in loss of life and
property, health and safety hazards, disruption of commerce and governmental services, extraordinary public
expenditures for flood protection and relief, and impairment of the tax base, all of which adversely affect the
public health, safety, and general welfare.
2. These flood losses are caused by uses that are inadequately elevated, floodproofed, or protected from
flood damage. The cumulative effect of obstructions in areas of special flood hazards that increase flood
heights and velocities also contributes to flood losses.
C. Statement of Purpose. It is the purpose of this chapter to promote the public health, safety, and general
welfare, and to minimize public and private losses due to flood conditions in specific areas by legally enforceable
regulations applied uniformly throughout the community to all publicly and privately owned land within flood-
prone, mudslide (i.e., mudflow), and/or flood-related erosion areas. These regulations are designed to:
1. Protect human life and health;
2. Minimize expenditure of public money for costly flood control projects;
3. Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the
expense of the general public;
4. Minimize prolonged business interruptions;
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5. Minimize damage to public facilities and utilities such as water and gas mains; electric, telephone and
sewer lines; and streets and bridges located in areas of special flood hazard;
6. Help maintain a stable tax base by providing for the sound use and development of areas of special flood
hazard so as to minimize future blighted areas caused by flood damage;
7. Ensure that potential buyers are notified that property is in an area of special flood hazard; and
8. Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions.
D. Methods of Reducing Flood Losses. To accomplish its purposes, this chapter includes regulations to:
1. Restrict or prohibit uses that are dangerous to health, safety, and property due to water or erosion
hazards, or that result in damaging increases in erosion or flood heights or velocities;
2. Require that uses vulnerable to floods, including facilities that serve such uses, be protected against flood
damage at the time of initial construction;
3. Control the alteration of natural floodplains, stream channels, and natural protective barriers which help
accommodate or channel floodwaters;
4. Control filling, grading, dredging, and other development that may increase flood damage;
5. Prevent or regulate the construction of flood barriers that will unnaturally divert floodwaters or that may
increase flood hazards in other areas; and
6. These regulations take precedence over any less restrictive conflicting local laws, ordinances, and codes.
(Ord. 1650 § 3 (Exh. B), 2018)
17.78.020 Definitions.
Words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common
usage and to give this chapter its most reasonable application, and as defined in Chapter 17.158 (General
Definitions) under “Floodplain Management Regulations.” (Ord. 1650 § 3 (Exh. B), 2018)
17.78.030 General provisions.
A. Lands to Which This Chapter Applies. This chapter shall apply to all areas of special flood hazards and where
specifically identified, XB zones, within the jurisdiction of the city.
B. Basis for Establishing the Areas of Special Flood Hazard. The areas of special flood hazard identified by the
Federal Emergency Management Agency (FEMA) in the “Flood Insurance Study (FIS) for the City of San Luis Obispo,
California in San Luis Obispo County” dated October 1978, with accompanying flood insurance rate maps (FIRMs)
and flood boundary and floodway maps (FBFMs), dated April 1979, and all subsequent amendments and/or
revisions, are hereby adopted by reference and declared to be a part of this chapter. This FIS and attendant
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mapping are the minimum areas of applicability of this chapter and may be supplemented by studies for other
areas, including local experience and historical data which allow implementation of this chapter and which are
recommended to the council by the floodplain administrator to be included in the regulated area. The study,
FIRMs, and FBFMs are on file at the Department of Public Works, 919 Palm Street.
C. Compliance. No structure or land shall hereafter be constructed, located, extended, converted, or altered
without full compliance with the terms of this chapter and other applicable regulations. Violation of the
requirements (including violations of conditions and safeguards) shall constitute a misdemeanor. Nothing here
shall prevent the council from taking such lawful action as is necessary to prevent or remedy any violation.
D. Abrogation and Greater Restrictions. This chapter is not intended to repeal, abrogate, or impair any existing
easements, covenants, or deed restrictions. However, where this chapter and another ordinance, easement,
covenant, or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail.
E. Interpretation. In the interpretation and application of this chapter, all provisions shall be:
1. Considered as minimum requirements;
2. Liberally construed in favor of the governing body; and
3. Deemed neither to limit nor repeal any other powers granted under state statutes.
F. Warning and Disclaimer of Liability. The degree of flood protection required by this chapter is considered
reasonable for regulatory purposes and is based on scientific and engineering considerations. Larger floods can
and will occur on rare occasions. Flood heights may be increased by human-made or natural causes. This chapter
does not imply that land outside the areas of special flood hazards or uses allowed within such areas will be free
from flooding or flood damages. This chapter shall not create liability on the part of the council, any officer or
employee thereof, the state, or the Federal Emergency Management Agency, for any flood damages that result
from reliance on this chapter or any administrative decision lawfully made hereunder. (Ord. 1650 § 3 (Exh. B),
2018)
17.78.040 Administration.
A. Designation of the Floodplain Administrator. The public works director or his/her designee is hereby appointed
to administer, implement, and enforce this chapter by granting or denying development permits in accord with its
provisions.
B. Duties and Responsibilities of the Floodplain Administrator. The duties and responsibilities of the floodplain
administrator shall include but not be limited to the following:
1. Permit Review. Review all development permits to determine:
a. Permit requirements of this chapter have been satisfied, including determination of substantial
improvement and substantial damage of existing structures;
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b. The applicant was advised other local, state or federal permits may be required;
c. The site is reasonably safe from flooding;
d. The proposed development does not adversely affect the carrying capacity of areas where base flood
elevations have been determined but a floodway has not been designated. This means that the
cumulative effect of the proposed development when combined with all other existing and anticipated
development will not increase the water surface elevation of the base flood more than one foot at any
point within the city;
e. If the proposed development is within a designated infill area, special floodplain management zone,
or the Mid-Higuera Specific Plan Area as defined by the Drainage Design Manual, that the more stringent
requirements of the manual have been met; and
f. All letters of map revision (LOMRs) for flood control projects are approved prior to the issuance of
building permits. Building permits must not be issued based on conditional letters of map revision
(CLOMRs). Approved CLOMRs allow construction of the proposed flood control project and land
preparation as specified in the “start of construction” definition.
2. Development of Substantial Improvement and Substantial Damage Procedures.
a. Using FEMA publication FEMA 213, “Answers to Questions About Substantially Damaged Buildings,”
develop detailed procedures for identifying and administering requirements for substantial improvement
and substantial damage, to include defining “market value.”
b. Ensure procedures are coordinated with other departments/divisions and implemented by
community development department staff.
3. Review, Use, and Development of Other Base Flood Data. When base flood elevation data has not been
provided in compliance with Section 17.78.030(B) (Basis for Establishing the Areas of Special Flood Hazard),
the floodplain administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway
data available from a Federal or State agency, or other source, in order to administer Section 17.78.050
(Provisions for Flood Hazard Reduction).
NOTE: A base flood elevation may be obtained using one of two methods from the FEMA publication FEMA
265, “Managing Floodplain Development in Approximate Zone A Areas—A Guide for Obtaining and Developing
Base (100-Year) Flood Elevations” dated July 1995.
4. Notification of Other Agencies.
a. Alteration or Relocation of a Watercourse.
i. Notify adjacent communities and the California Department of Water Resources prior to
alteration or relocation;
ii. Submit evidence of such notification to the Federal Emergency Management Agency; and
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iii. Ensure that the flood carrying capacity within the altered or relocated portion of the watercourse
is maintained.
b. Base Flood Elevation Changes Due to Physical Alterations.
i. Within six months of information becoming available or project completion, whichever comes
first, the floodplain administrator shall submit or ensure that the permit applicant submits technical
or scientific data to FEMA for a letter of map revision (LOMR).
ii. All LOMRs for flood control projects are approved prior to the issuance of building permits.
Building permits must not be issued based on conditional letters of map revision (CLOMRs).
Approved CLOMRs allow construction of the proposed flood control project and land preparation as
specified in the “start of construction” definition.
Such submissions are necessary so that upon confirmation of those physical changes affecting
flooding conditions, risk premium rates and floodplain management requirements are based on
current data.
c. Changes in Corporate Boundaries. Notify FEMA in writing whenever the corporate boundaries have
been modified by annexation or other means and include a copy of a map of the community clearly
delineating the new corporate limits.
5. Documentation of Floodplain Development. Obtain and maintain for public inspection and make available as
needed the following:
a. Certification required by Sections 17.78.050(A)(3) and 17.78.050(D) (lowest floor elevations);
b. Certification required by Section 17.78.050(A)(3) (elevation or floodproofing of nonresidential
structures);
c. Certification required by Section 17.78.050(A)(3) (wet floodproofing standard);
d. Certification of elevation required by Section 17.78.050(C)(1) (subdivisions and other proposed
development standards);
e. Certification required by Section 17.78.050(F)(2) (floodway encroachments); and
f. Maintain a record of all variance actions, including justification for their issuance, and report such
variances issued in its biennial report submitted to FEMA.
6. Map Determination. Make interpretations, where needed, as to the exact location of the boundaries of the
areas of special flood hazard where there appears to be a conflict between a mapped boundary and actual
field conditions. The person contesting the location of the boundary shall be given a reasonable opportunity
to appeal the interpretation as provided in subsection (D) of this section.
7. Remedial Action. Take action to remedy violations of this chapter as specified in Section 17.78.030(C)
(Compliance).
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8. Biennial Report. Complete and submit biennial report to FEMA.
9. Planning. Ensure the general plan is consistent with floodplain management objectives here.
10. Nonconversion of Enclosed Areas Below the Lowest Floor. To ensure that the areas below one foot above the
base flood elevation (BFE) shall be used solely for parking vehicles, limited storage, or access to the building
and not be finished for use as human habitation without first becoming fully compliant with the floodplain
management ordinance in effect at the time of conversion, the floodplain administrator shall:
a. Determine which applicants for new construction and/or substantial improvements have fully
enclosed areas below the lowest floor that are five feet or higher;
b. Obtain a “Conversion Agreement for Construction Within Flood Hazard Areas” or equivalent between
the property owner and the city. The agreement shall be recorded with the county of San Luis Obispo
recorder as a deed restriction. The conversion agreement shall be in a form acceptable to the floodplain
administrator and city attorney and:
i. Condition the property that there shall be no conversion of enclosed areas below the lowest floor
elevation without first becoming fully compliant with this chapter and other city requirements.
ii. Have the authority granted to the city to inspect any area of a structure below the base flood
elevation to ensure compliance upon prior notice of at least seventy-two hours.
C. Development Permit. A development permit shall be obtained before any construction or other development,
including manufactured homes, within any area of special flood hazard established in Section 17.78.030(B) (Basis
for Establishing the Areas of Special Flood Hazard). Application for a development permit shall be made on forms
furnished by the city. The applicant shall provide the following minimum information:
1. Plans in duplicate, drawn to scale, showing:
a. Location, dimensions, and elevation of the area in question, existing or proposed structures, storage
of materials and equipment and their location;
b. Proposed locations of water supply, sanitary sewer, and other utilities;
c. Grading information showing existing and proposed contours, any proposed fill, and drainage
facilities;
d. Location of the regulatory floodway when applicable;
e. Base flood elevation information as specified in Sections 17.78.030(B) (Basis for Establishing the Areas
of Special Flood Hazard) or subsection (B)(3) (Review, Use, and Development of Other Base Flood Data) of
this section;
f. Proposed elevation in relation to mean sea level, of the lowest floor (including basement) of all
structures; and
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g. Proposed elevation in relation to mean sea level to which any nonresidential structure will be
floodproofed, as required in Section 17.78.050(A)(3) (Elevation and Floodproofing) and detailed in FEMA
Technical Bulletin TB 3-93.
2. Certification from a registered civil engineer or architect that the nonresidential floodproofed building
meets the floodproofing criteria in Section 17.78.050(A)(3) (Elevation and Floodproofing).
3. For a crawlspace foundation, location and total net area of foundation openings as required in Section
17.78.050(A)(3) (Elevation and Floodproofing) and detailed in FEMA Technical Bulletins 1-93 and 7-93.
4. Description of the extent to which any watercourse will be altered or relocated as a result of proposed
development.
5. All appropriate certifications listed in subsection (B)(5) (Documentation of Floodplain Development) of this
section.
D. Appeals. The council shall hear and decide appeals when it is alleged there is an error in any requirement,
decision, or determination made by the floodplain administrator in the enforcement or administration of this
chapter. (Ord. 1650 § 3 (Exh. B), 2018)
17.78.050 Provisions for flood hazard reduction.
A. Standards of Construction. In all areas of special flood hazards, the following standards are required:
1. Anchoring. All new construction and substantial improvements of structures, including manufactured
homes, shall be adequately anchored to prevent flotation, collapse, or lateral movement of the structure
resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
2. Construction Materials and Methods. All new construction and substantial improvements of structures,
including manufactured homes, shall be constructed:
a. With flood-resistant materials, and utility equipment resistant to flood damage for areas below the
base flood elevation;
b. Using methods and practices that minimize flood damage;
c. With electrical, heating, ventilation, plumbing and air conditioning equipment, and other service
facilities that are designed and/or located so as to prevent water from entering or accumulating within the
components during conditions of flooding; and
d. Within zones AH or AO, so that there are adequate drainage paths around structures on slopes to
guide floodwaters around and away from proposed structures.
3. Elevation and Floodproofing.
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a. Residential Construction. Upon the completion of the structure, the elevation of the lowest floor,
including basement, shall be certified by a registered civil engineer or licensed land surveyor, and verified
by the Building Official to be properly elevated. Such certification and verification shall be provided to the
floodplain administrator. All new construction or substantial improvements of residential structures shall
have the lowest floor, including basement:
i. In AE, AH, A1-30 zones, elevated one foot above the base flood elevation.
ii. In an AO zone, elevated above the highest adjacent grade to a height one foot above the depth
number specified in feet on the FIRM, or elevated at least three feet above the highest adjacent grade
if no depth number is specified.
iii. In an A zone, without BFEs specified on the FIRM [unnumbered A zone], elevated one foot above
the base flood elevation; as determined under Section 17.78.040(B)(3) (Review, Use, and Development
of Other Base Flood Data).
iv. In an XB zone, above the base flood elevation.
b. Nonresidential Construction. All new construction or substantial improvements of nonresidential
structures shall either be elevated to conform with subsection (A)(3) (Elevation and Floodproofing) of this
section or:
i. Be floodproofed, together with attendant utility and sanitary facilities, below the elevation
recommended under subsection (A)(3) (Elevation and Floodproofing) of this section, so that the
structure is watertight with walls substantially impermeable to the passage of water;
ii. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects
of buoyancy; and
iii. Be certified by a registered civil engineer or architect that the standards of subsection (A)(3)
(Elevation and Floodproofing) of this section are satisfied. Such certification shall be provided to the
floodplain administrator.
c. Flood Openings. All new construction and substantial improvements of structures with fully enclosed
areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building
access or storage, and which are subject to flooding, shall be designed to automatically equalize
hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwater. Designs for
meeting this requirement must meet the following minimum criteria:
i. For nonengineered openings:
(a) Have a minimum of two openings on different sides having a total net area of not less than
one square inch for every square foot of enclosed area subject to flooding;
(b) The bottom of all openings shall be no higher than one foot above grade;
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(c) Openings may be equipped with screens, louvers, valves or other coverings or devices;
provided, that they permit the automatic entry and exit of floodwater; and
(d) Buildings with more than one enclosed area must have openings on exterior walls for each
area to allow floodwater to directly enter; or
ii. Be certified by a registered civil engineer or architect.
d. Manufactured Homes.
i. Manufactured homes located outside of manufactured home parks or subdivisions shall meet
the elevation and floodproofing requirement in subsection (A)(3) (Elevation and Floodproofing) of this
section.
ii. Manufactured homes placed within manufactured home parks or subdivisions shall meet the
standards in subsection D (Standards for Manufactured Homes Within Manufactured Home Parks or
Subdivisions) of this section. Additional guidance may be found in FEMA Technical Bulletins TB 1-93
and TB 7-93.
e. Garages and Low-Cost Accessory Structures.
i. Attached Garages.
(a) A garage attached to a residential structure, constructed with the garage floor slab below the
BFE, must be designed to allow for the automatic entry of floodwaters. See subsection (A)(3)
(Elevation and Floodproofing) of this section. Areas of the garage below the BFE must be
constructed with flood-resistant materials. See subsection (A)(2) (Construction Materials and
Methods) of this section.
(b) A garage attached to a nonresidential structure must meet the above requirements or be
dry floodproofed. For guidance on below-grade parking areas, see FEMA Technical Bulletin TB-6.
ii. Detached Garages and Accessory Structures.
(a) Accessory structures used solely for parking (two-car detached garages or smaller) or limited
storage (small, low-cost sheds), as defined in Section 17.158.016—F Definitions, under Floodplain
Management Regulations, may be constructed such that its floor is below the base flood
elevation (BFE), provided the structure is designed and constructed in compliance with the
following requirements:
(1) Use of the accessory structure must be limited to parking or limited storage;
(2) The portions of the accessory structure located below the BFE must be built using flood-
resistant materials;
(3) The accessory structure must be adequately anchored to prevent flotation, collapse, and
lateral movement;
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(4) Any mechanical and utility equipment in the accessory structure must be elevated or
floodproofed to or above the BFE;
(5) The accessory structure must comply with floodplain encroachment provisions in
subsection F (Floodways) of this section; and
(6) The accessory structure must be designed to allow for the automatic entry of
floodwaters in compliance with subsection (A)(3) (Elevation and Floodproofing) of this
section.
(b) Detached garages and accessory structures not meeting the above standards must be
constructed in compliance with all applicable standards in subsection A (Standards of
Construction) of this section.
B. Standards for Utilities.
1. All new and replacement water supply and sanitary sewage systems shall be designed to minimize or
eliminate:
a. Infiltration of floodwaters into the systems; and
b. Discharge from the systems into floodwaters.
2. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them
during flooding.
C. Standards for Subdivisions and Other Proposed Development.
1. All new subdivisions proposals and other proposed development, including proposals for manufactured
home parks and subdivisions, greater than fifty lots or five acres, whichever is the lesser, shall:
a. Identify the special flood hazard areas (SFHA) and base flood elevations (BFE).
b. Identify the elevations of lowest floors of all proposed structures and pads on the final plans.
c. If the site is filled above the base flood elevation, the following as-built information for each structure
shall be certified by a registered civil engineer or licensed land surveyor and provided as part of an
application for a letter of map revision based on fill (LOMR-F) to the floodplain administrator:
i. Lowest floor elevation.
ii. Pad elevation.
iii. Lowest adjacent grade.
2. All subdivision proposals and other proposed development shall be consistent with the need to minimize
flood damage.
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3. All subdivision proposals and other proposed development shall have public utilities and facilities such as
sewer, gas, electrical and water systems located and constructed to minimize flood damage.
4. All subdivisions and other proposed development shall provide adequate drainage to reduce exposure to
flood hazards.
D. Standards for Manufactured Homes Within Manufactured Home Parks or Subdivisions. All manufactured homes in
special flood hazard areas shall meet the anchoring standards in subsection (A)(1) (Anchoring) of this section,
construction materials and methods requirements in subsection (A)(2) (Construction Materials and Methods) of
this section, flood openings requirements in subsection (A)(3) (Elevation and Floodproofing) of this section, and
garages and low-cost accessory structure standards in subsection (A)(3) (Elevation and Floodproofing) of this
section. Manufactured homes located outside of manufactured home parks or subdivisions shall meet the
elevation and floodproofing requirement in subsection (A)(3) of this section.
1. All manufactured homes that are placed or substantially improved on sites located: (a) in a new
manufactured home park or subdivision; (b) in an expansion to an existing manufactured home park or
subdivision; or (c) in an existing manufactured home park or subdivision on a site upon which a manufactured
home has incurred “substantial damage” as the result of a flood shall within zones A1-30, AH, and AE on the
community’s flood insurance rate map, shall be elevated on a permanent foundation such that the lowest
floor of the manufactured home is elevated one foot above the base flood elevation and be securely fastened
to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
2. All manufactured homes to be placed or substantially improved on sites in an existing manufactured
home park or subdivision within zones A1-30, AH, and AE on the community’s flood insurance rate map that
are not subject to the provisions of subsection (D)(1) of this section shall be securely fastened to an
adequately anchored foundation system to resist flotation, collapse, and lateral movement, and be elevated
so that either the:
a. Lowest floor of the manufactured home is at least one foot above the base flood elevation; or
b. Manufactured home chassis is supported by reinforced piers or other foundation elements of at least
equivalent strength that are no less than thirty-six inches in height above grade.
Upon the completion of the structure, the elevation of the lowest floor, including basement, shall be certified
by a registered civil engineer or licensed land surveyor, and verified by the building official, to be properly
elevated. Such certification and verification shall be provided to the floodplain administrator.
E. Standards for Recreational Vehicles.
1. All recreational vehicles placed in zones A1-30, AH, and AE shall either:
a. Be on the site for fewer than one hundred eighty consecutive days; or
b. Be fully licensed and ready for highway use. A recreational vehicle is ready for highway use if it is on
its wheels or jacking system, is attached to the site only by quick-disconnect-type utilities and security
devices, and has no permanently attached additions; or
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c. Meet the permit requirements of Section 17.78.040(C) (Development Permit) and the elevation and
anchoring requirements for manufactured homes in subsection (D)(1) of this section.
F. Floodways. Since floodways are extremely hazardous areas due to the velocity of floodwaters that carry debris,
potential projectiles, and erosion potential, the following provisions apply:
1. Until a regulatory floodway is adopted, no new construction, substantial development, or other
development, including fill, shall be allowed within zones A1-30 and AE unless it is demonstrated that the
cumulative effect of the proposed development, when combined with all other development, will not increase
the water surface elevation of the base flood more than one foot at any point within the city.
2. If the proposed development is within a designated infill area, special floodplain management zone, or
the Mid-Higuera Specific Plan Area as defined by the Drainage Design Manual, the more stringent
requirements of the manual apply.
3. Within an adopted regulatory floodway, the city shall prohibit encroachments, including fill, new
construction, substantial improvements, and other development, unless certification by a registered civil
engineer is provided demonstrating that the proposed encroachment shall not result in any increase in flood
levels during the occurrence of the base flood discharge.
4. If subsections (F)(1) and (F)(2) of this section are satisfied, all new construction, substantial improvement,
and other proposed new development shall comply with all other applicable flood hazard reduction
provisions of this subsection. (Ord. 1650 § 3 (Exh. B), 2018)
17.78.060 Variance procedure for floodplains.
A. Nature of Floodplain Variances. The issuance of a variance is for floodplain management purposes only.
Insurance premium rates are determined by statute according to actuarial risk and will not be modified by the
granting of a variance.
The variance criteria contained in this section of the chapter are based on the general principle of zoning law that
variances pertain to a piece of property and are not personal in nature. A variance may be granted for a parcel of
property with physical characteristics so unusual that complying with the requirements of this chapter would
create an exceptional hardship to the applicant or the surrounding property owners. The characteristics must be
unique to the property and not be shared by adjacent parcels. The unique characteristic must pertain to the land
itself, not to the structure, its inhabitants, or the property owners.
It is the duty of the council to help protect its citizens from flooding. This need is so compelling and the
implications of the cost of insuring a structure built below flood level are so serious that variances from the flood
elevation or from other requirements in this chapter are quite rare. The long-term goal of preventing and reducing
flood loss and damage can only be met if variances are strictly limited. Therefore, the variance guidelines provided
in this chapter are more detailed and contain multiple provisions that must be met before a variance can be
properly granted. The criteria are designed to screen out those situations in which alternatives other than a
variance are more appropriate.
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B. Conditions for Variances.
1. Generally, variances may be issued for new construction, substantial improvement, and other proposed
new development to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots
with existing structures constructed below the base flood level; provided, that the procedures of Sections
17.78.040 (Administration) and 17.78.050 (Provisions for Flood Hazard Reduction) of this chapter have been
fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing
the variance increases.
2. Variances may be issued for the repair or rehabilitation of “historic structures” (as defined in Chapter
17.158: General Definitions, under Floodplain Management Regulations) upon a determination that the
proposed repair or rehabilitation will not preclude the structure’s continued designation as a historic structure
and the variance is the minimum necessary to preserve the historic character and design of the structure.
3. Variances shall not be issued within any mapped regulatory floodway if any increase in flood levels during
the base flood discharge would result.
4. Variances shall only be issued upon a determination that the variance is the “minimum necessary,”
considering the flood hazard, to afford relief. “Minimum necessary” means to afford relief with a minimum of
deviation from the requirements of this chapter. For example, in the case of variances to an elevation
requirement, this means the council need not grant permission for the applicant to build at grade, or even to
whatever elevation the applicant proposes, but only to that elevation which the council believes will both
provide relief and preserve the integrity of this chapter.
5. Any applicant to whom a variance is granted shall be given written notice over the signature of the
floodplain administrator that:
a. The issuance of a variance to construct a structure below the base flood level will result in increased
premium rates for flood insurance up to amounts as high as twenty-five dollars for one hundred dollars
of insurance coverage; and
b. Such construction below the base flood level increases risks to life and property. It is recommended
that a copy of the notice shall be recorded by the floodplain administrator in the office of the County of
San Luis Obispo recorder and shall be recorded in a manner so that it appears in the chain of title of the
affected parcel of land.
6. The floodplain administrator shall maintain a record of all variance actions, including justification for his/
her issuance, and report such variances issued in its biennial report submitted to the Federal Emergency
Management Agency.
C. Authority to Grant Variances. Notwithstanding the provisions of Chapter 17.114 (Variances), the council shall be
responsible for conducting public hearings on variances pertaining to the provisions of this chapter and for acting
upon such variance applications.
1. In acting upon requests for variances, the council shall consider all technical evaluations, all relevant
factors and standards specified in other sections of this chapter, and the:
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a. Danger that materials may be swept onto other lands to the injury of others;
b. Danger of life and property due to flooding or erosion damage;
c. Susceptibility of the proposed facility and its contents to flood damage and the effect of such damage
on the existing individual owner and future owners of the property;
d. Importance of the services provided by the proposed facility to the community;
e. Necessity to the facility of a waterfront location, where applicable;
f. Availability of alternative locations for the proposed use which are not subject to flooding or erosion
damage;
g. Compatibility of the proposed use with existing and anticipated development;
h. Relationship of the proposed use to the general plan and floodplain management program for that
area;
i. Safety of access to the property in time of flood for ordinary and emergency vehicles;
j. Expected heights, velocity, duration, rate of rise, and sediment transport of the floodwaters expected
at the site; and
k. Costs of providing governmental services during and after flood conditions, including maintenance
and repair of public utilities and facilities such as sewer, gas, electrical, and water system, and streets and
bridges.
2. Variances shall only be issued upon a:
a. Showing of good and sufficient cause;
b. Determination that failure to grant the variance would result in exceptional hardship to the applicant;
and
c. Determination that the granting of a variance will not result in increased flood heights, additional
threats to public safety, or extraordinary public expense, create a public nuisance, cause fraud and
victimization of the public, or conflict with existing local laws or ordinances.
3. Variances may be issued for new construction, substantial improvement, and other proposed new
development necessary for the conduct of a functionally dependent use; provided, that the provisions of
subsections (C)(1) through (C)(4) of this section are satisfied and that the structure or other development is
protected by methods that minimize flood damages during the base flood and does not result in additional
threats to public safety and does not create a public nuisance.
4. Upon consideration of the factors of subsection B of this section and the purposes of this chapter, the
council may attach such conditions to the granting of variances as it deems necessary to further the purposes
of this chapter. (Ord. 1650 § 3 (Exh. B), 2018)
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The San Luis Obispo Municipal Code is current through Ordinance 1720, passed August 16, 2022.
Disclaimer: The City Clerk's Office has the official version of the San Luis Obispo Municipal Code. Users should
contact the City Clerk's Office for ordinances passed subsequent to the ordinance cited above.
City Website: www.slocity.org
City Telephone: (805) 781-7100
Code Publishing Company
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RESILIENT SLO 1RESILIENT SLO CLIMATE CHANGE HAZARDS AND VULNERABILITY ASSESSMENT REPORT SUMMARY The climate is changing, and the pace of global warming is rapidly increasing from human activities. According to the Intergovernmental Panel on Climate Change, human-caused climate change is likely to increase the global average temperature by 1.5 degrees Celsius (2.7° Fahrenheit) between 2030 and 2052. If warming is higher than 1.5 degrees Celsius, many natural systems that sustain life will be pushed past a dangerous turning point and have limited ability to recover. While the global community continues to work to reduce greenhouse gas emissions moving forward, historic global greenhouse gas emissions have already solidified permanent changes to the environment. These changes bring substantial impacts to the world, the state, the region, and the City of San Luis Obispo. Acknowledging the severity of these impacts and the importance of preparedness and resilience, the City of San Luis Obispo City Council has identified climate adaptation and resilience as a top priority. RESILIENT SLO OVERVIEWThe City is conducting the Resilient SLO project, a community-led initiative to improve com-munity resilience to the worsening impacts of climate change. To learn more about the proj-ect and keep up to date, visit the Resilient SLO website at: www.lgc.org/resilient-slo/.This booklet provides key highlights and findings from the City’s Climate Change Hazards and Vulnerabilities Report (Report). The Report assesses how climate change will impact the City by identifying:•The City’s exposure to climate-related hazards •Potential impacts of climate-related hazards•Populations in the community that are most vulnerable to climate change impacts •City infrastructure and ecosystems that are vulnerable to climate change impacts •The City’s existing capacity to address climate change impacts. The Report focuses on four key climate-related hazards: Drought, Flooding, Wildfire, and Extreme Heat. To help better understand how these hazards will affect different components of the City, the analysis of impacts has been organized into three categories listed and defined below. •Natural Systems – This category includes systems or system components of the natural environment (e.g., forests and grasslands, flora and fauna, stream health) in the City and the surrounding region that are critical to overall ecosystem health. •Built Environment – This category includes the physical assets that comprise the City’s built environment (e.g., roadway network, buildings, utility systems, stormwater management system) that are critical to supporting normal community functions in the City. •Community Resilience – This category includes human-focused systems that provide essential services to residents and visitors in the City and are critical to maintaining normal community functions (e.g., economic activity, healthcare system, schools). DROUGHTFLOODINGWILDFIREEXTREME HEA T Page 641 of 669
2 RESILIENT SLOWHAT IS THE CITY ALREADY DOING?FLOODINGBecause flooding has been an issue in SLO, historically, The City is already supporting or implementing a comprehensive set of plans and policies with regional partners to reduce the risk of flood impacts including: •Through the County’s Flood Control District, the Mid-Higuera Bypass Project is proposed to increase the flood control capacity of the San Luis Obispo Creek between Marsh Street and Madonna Road.•the City’s Local Hazard Mitigation Plan that includes strategies to reduce risk from flooding events;•the City’s Waterway Management Plan to address flooding, erosion, water quality, and ecological issues in the San Luis Obispo Creek Watershed; and •the City’s participation in the National Pollution Discharge Elimination System Program which includes requirements to help manage urban stormwater.DROUGHTBecause drought is not new to the central coast region, the City already has a comprehensive set of initiatives and resources to address drought including: •the Urban Water Management Plan and Water Shortage Contingency Plan to manage the City’s water supply, •the Recycled Water Master Plan for use of recycled water in the City, and•the San Luis Valley Groundwater Sustainability Plan to manage groundwater resources.Page 642 of 669
RESILIENT SLO 3WILDFIREThe City and regional partners are already implementing a comprehensive set of plans and policies to reduce the risk of wildfire impacts including: •implementing the City’s Community Wildfire Protection Plan to minimize wildfire risk to areas in and around the City limits;•implementing the City’s Vegetation Management Plan: The Wildland‐ Urban Interface to reduce wildfire risk in the City’s open space areas; and the development of the Comprehensive Disaster Leadership Plan which includes procedures and protocols to be implemented during emergency evacuation events as well as during utility disruptions (e.g., electricity, telecommunications). •Central Coast Community Energy (3CE) as well as Pacific Gas & Electric have begun to help fund the installation of reliable backup power systems for public and private entities operating critical facilities, increasing energy resilience during utility disruptions. •Pacific Gas & Electric Company has begun the hardening of their electrical equipment and conducting fuel reduction efforts around energized lines to reduce the likelihood of an equipment-caused fire and reduce the frequency of future Public Safety Power Shutoff events. EXTREME HEATCurrently, the City does not have comprehensive plans and policies to address extreme heat because, historically, extreme heat has not been an issue. However, the Climate Action Plan for Community Recovery includes a measure to plan 10,000 new trees by 2035 which will contribute some shade to the City landscape, and the Parks and Recreation blueprint for the Future 2021-2041 includes some shade infrastructure for City parks. As temperatures continue to change, the City will be working to address extreme heat through services and policies. Page 643 of 669
4 RESILIENT SLOENVIRONMENTAL JUSTICE AND VULNERABLE POPULATIONSENVIRONMENTAL JUSTICE OVERVIEW DISADVANTAGED COMMUNITIES IN SAN LUIS OBISPOTo read more about the SLOCOG’s assessment, visit: https://www.slocog.org/programs/data-services/gis-mapping/disadvantaged-communities ENVIRONMENTAL JUSTICE The fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income, with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies.According to the U.S. Environmental Protection Agency, environmental justice can be defined as the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income, with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies. As the City continues to plan for the impacts of climate change, it is important to recognize that certain populations and areas of the City are more vulnerable to climate-related impacts (e.g., flooding, extreme heat). As identified in the Report, populations with specific vulnerabilities are concentrated in key areas of the City and have the potential to overlap with key climate-related hazards that place these populations at a disproportionate level of risk from climate impacts. In general, low-income residents, communities of color, tribal nations, and immigrant communities have disproportionately experienced some of the greatest environmental burdens and related health problems throughout the history of the U.S. and in California. These historic inequities are, in the majority of cases, not a coincidence but a result of inappropriate zoning and negligent land use planning, intersecting structural inequalities, failure to enforce proper zoning or conduct regular inspections, deed restrictions, and other discriminatory housing and lending practices, limited political and economic power among certain demographics, the prioritization of business interests over public health, development patterns that tend to concentrate pollution and environmental hazards in certain communities, and the placement of economic and environmental benefits in areas outside of disadvantaged communities. DISADVANTAGED COMMUNITIES Disproportionately burdened areas that are economically distressed and/or historically underrepresented as a part of the local government process.The San Luis Obispo Council of Governments (SLOCOG) has created a regional definition of disadvantaged communities to help distribute funds more equitably and meet State and federal environmental justice requirements. In the San Luis Obispo Region, disadvantaged communities are defined as disproportionately burdened areas that are economically distressed and/or historically underrepresented as a part of the local government process. The SLOCOG Disadvantaged Communities Assessment has identified 13 variables that address a wide range of socioeconomic and population-based factors to geographically define these disproportionately burdened areas. Page 644 of 669
RESILIENT SLO 5The map on the right includes the areas with the City of San Luis Obispo with regionally defined disadvantaged communities.Included below are key findings from the social vulnerability analysis which is included in the Report:ŝƐĂĚǀĂŶƚĂŐĞĚŽŵŵƵŶŝƟĞƐŝŶƚŚĞŝƚLJŽĨ^ĂŶ>ƵŝƐKďŝƐƉŽUnhoused Populations: The city’s homeless population is particularly vulnerable to climate-related hazards with less access to shelter and resources to protect themselves during emergency events (e.g., flooding, heat waves). Shelters and encampments built by unhoused individuals are often developed in or near flood plains and areas with higher wildfire risk, placing these populations at increased risk during emergency events, particularly in areas with lower levels of access to transportation.Vulnerable Neighborhoods: The neighborhood to the east of South Higuera Street along Margarita Avenue and Prado Road, as well as the neighborhood west of South Higuera Street near Tank Farm Road, stand out as a particularly vulnerable area of the City. Notable characteristics of these areas include a high percentage of elderly and disabled residents, a high percentage of residents experiencing linguistic isolation (i.e., speaking a language other than English at home), low access to supermarkets and grocery stores, and a larger percentage of residents earning less than 200% of the federal poverty level. Cost of Living: Overall, the cost of living in the City is high relative to household income. According to data from the U.S. Census Bureau, around 57 percent of renters in the City spend 35 percent or more of their income on rent. The high cost of living makes these residents more vulnerable to climate-related hazard events with less financial resources to prepare and recover from these events. DISADVANTAGED COMMUNITIES IN SAN LUIS OBISPOPage 645 of 669
6 RESILIENT SLODROUGHTPrecipitation patterns in California shift between dry and wet multi-year periods. Climate change is projected to intensify these seasonal extremes. Dry periods are projected to become dryer and wet periods wetter, leading to longer and more severe droughts when they do occur. While average annual precipitation in the County is projected to trend upward in future years, precipitation patterns are expected to become more volatile, with potentially less frequent but more intense storms that produce above average amounts of precipitation.CHANGES IN DROUGHT RISKANNUAL PRECIPITATIONƵƌŝŶŐŶŽŶͲĚƌŽƵŐŚƚƉĞƌŝŽĚƐ͕ĂŶŶƵĂůĂǀĞƌĂŐĞƉƌĞĐŝƉŝƚĂƟŽŶŝŶ^ĂŶ>ƵŝƐKďŝƐƉŽŽƵŶƚLJŝƐƉƌŽ-ũĞĐƚĞĚƚŽINCREASE FROM 16.1 INCHES TO 19.8 INCHES BY AS EARLY AS 2070.,ŽǁĞǀĞƌ͕ƚŚŝƐŝŶĐƌĞĂƐĞĚƉƌĞĐŝƉŝƚĂƟŽŶǁŝůůĐŽŵĞƚŚƌŽƵŐŚůĞƐƐĨƌĞƋƵĞŶƚďƵƚŵŽƌĞŝŶƚĞŶƐĞƌĂŝŶĨĂůůĞǀĞŶƚƐ͘LONG-TERM DROUGHTůŝŵĂƚĞĐŚĂŶŐĞǁŝůůŝŶĐƌĞĂƐĞƚŚĞůŝŬĞůŝŚŽŽĚŽĨĂůŽŶŐͲƚĞƌŵ;ϮϬͲLJĞĂƌͿĚƌŽƵŐŚƚŽĐĐƵƌƌŝŶŐ͕ǁŝƚŚAVERAGE ANNUAL RAINFALL DECREASING 17% FOR UP TO 20 YEARS. WHIPLASH EVENTS^ŚŝŌƐďĞƚǁĞĞŶĞdžƚƌĞŵĞůLJĚƌLJĂŶĚĞdžƚƌĞŵĞůLJǁĞƚŵƵůƟͲLJĞĂƌƉĞƌŝŽĚƐ͕ǁŚŝĐŚŚĂǀĞŽĐĐƵƌƌĞĚŚŝƐƚŽƌŝĐĂůůLJŝŶƚŚĞƐƚĂƚĞ͕ĂƌĞĂŶƟĐŝƉĂƚĞĚƚŽďĞ-ĐŽŵĞŵŽƌĞƐĞǀĞƌĞǁŝƚŚRAPID SHIFTS FROM DRY TO WET PERIODSŬŶŽǁŶĂƐ͞ǁŚŝƉůĂƐŚĞǀĞŶƚƐ͘͟Nacimiento ReservoirCurrent Storage: 87,740 acre-feetCapacity: 377,900 acre-feet% of Total: 18%Historical average July % capacity: 44%Whale Rock ReservoirCurrent Storage: 29,703 acre-feetCapacity: 38,967 acre-feet% of Total: 76%Historical average July % capacity: 65%76%64%Updated: 07-14-2118%Salinas River Reservoir Current Storage: 15,533 acre-feetCapacity: 23,843 acre-feet% of Total: 64%Historical average July % capacity: 62%Note: Percent of average is based on the average capacity of thereservoir during the current month for the period 2008 to present, when the City began receiving water from Nacimiento Reservoir.ObispoSan Luis ŝƚLJŽĨ^ĂŶ>ƵŝƐKďŝƐƉŽDƵůƟͲ^ŽƵƌĐĞtĂƚĞƌ^ƵƉƉůLJEĞƚǁŽƌŬĂŶĚ^ƚŽƌĂŐĞ>ĞǀĞůƐ;:ƵůLJϮϬϮϭͿLong-Term Drought ScenarioPage 646 of 669
RESILIENT SLO 7In the future, drought scenarios will have the largest potential impact on natural systems (e.g., plants and an-imals, urban trees, landscaped ar-eas) and the City’s water supply (i.e., Whale Rock Reservoir, Salinas Reser-voir, Nacimiento Reservoir, and recy-cled water). Future drought scenarios could result in voluntary or mandatory water use reductions for City residents and businesses. However, the City in-corporates climate-related projections into long-range water resource plans.DROUGHTZĂŝŶĨĂůůƌƵŶŽīƚŚĂƚĚƌĂŝŶƐŝŶƚŽƚŚĞŝƚLJ͛ƐƌĞƐĞƌǀŽŝƌƐƌĞƐƵůƚƐŝŶƚŚĞďƵŝůĚƵƉŽĨƐĞĚŝŵĞŶƚĂŶĚĐĂŶƌĞĚƵĐĞƚŚĞƌĞƐĞƌǀŽŝƌ͛ƐŽǀĞƌĂůůǁĂƚĞƌƐƚŽƌĂŐĞĐĂƉĂĐŝƚLJ͘>ĂŶĚƐĐĂƉĞĚŝƐƚƵƌďĂŶĐĞƐŝŶĐůƵĚŝŶŐǁŝůĚĮƌĞ͕ƉŽƐƚͲǁŝůĚĮƌĞƌƵŶŽī͕ŽƌůĂŶĚƐůŝĚĞƐĂŌĞƌǁĞƚǁŝŶƚĞƌƐ͕ĂƌĞƉƌŽũĞĐƚĞĚƚŽŝŶĐƌĞĂƐĞƐĞĚŝŵĞŶƚĂƟŽŶŝŶƌĞƐĞƌǀŽŝƌƐŝŶƚŚĞĐĞŶƚƌĂůĐŽĂƐƚƌĞŐŝŽŶŝŶƚŚĞĨƵƚƵƌĞ͘dŚŝƐŚĂƐƚŚĞƉŽƚĞŶƟĂůƚŽĂīĞĐƚƚŚĞŝƚLJ͛ƐǁĂƚĞƌƐƵƉƉůLJ͘,ŽǁĞǀĞƌ͕ƚŚĞŝƚLJƉƌŽĂĐƟǀĞůLJŝŵƉůĞŵĞŶƚƐďĞƐƚŵĂŶĂŐĞŵĞŶƚƉƌĂĐƟĐĞƐƚŽƌĞĚƵĐĞĞƌŽƐŝŽŶĂŶĚƐĞĚŝŵĞŶƚĂƟŽŶŝŶŝƚƐƌĞƐĞƌǀŽŝƌƐ͘>ŽŶŐͲƚĞƌŵĚƌŽƵŐŚƚƐĐĞŶĂƌŝŽƐŵĂLJƌĞƐƵůƚŝŶŝŶƚĞŶƐŝĮĞĚǁĂƚĞƌĐŽŶƐĞƌǀĂƟŽŶŵĞĂƐƵƌĞƐĨŽƌƌĞƐŝĚĞŶƚƐĂŶĚďƵƐŝŶĞƐƐĞƐŝŶƚŚĞŝƚLJ͘&ƵƚƵƌĞůŽŶŐͲƚĞƌŵĚƌŽƵŐŚƚĐŽƵůĚƌĞƐƵůƚŝŶƚŚĞŝŶĐƌĞĂƐĞĚƉƌĞǀĂůĞŶĐĞŽĨĐĞƌƚĂŝŶǀĞĐƚŽƌͲďŽƌŶĞĚŝƐĞĂƐĞƐƉƌĞƐĞŶƚŝŶƚŚĞĐĞŶƚƌĂůĐŽĂƐƚƌĞŐŝŽŶŝŶĐůƵĚŝŶŐ>LJŵĞĚŝƐĞĂƐĞĂŶĚǀĂůůĞLJĨĞǀĞƌ͘dŚĞŝƚLJ͛ƐĚĞƐŝŐŶĂƚĞĚŽƉĞŶƐƉĂĐĞĂƌĞĂƐŝŶĐůƵĚĞĂŵŝdžƚƵƌĞŽĨǀĞŐĞƚĂƟŽŶƚLJƉĞƐŝŶĐůƵĚŝŶŐŽĂŬǁŽŽĚůĂŶĚ͕ŐƌĂƐƐůĂŶĚ͕ĐŽĂƐƚĂůƐĂŐĞƐĐƌƵď͕ĂŶĚĐŚĂƉĂƌƌĂůƚŚĂƚĂƌĞůŝŬĞůLJƚŽďĞŝŵƉĂĐƚĞĚďLJůŽŶŐͲƚĞƌŵĚƌŽƵŐŚƚƐ͘ƐĚƌLJLJĞĂƌƐĂŶĚůŽŶŐͲƚĞƌŵĚƌŽƵŐŚƚƐďĞĐŽŵĞŵŽƌĞĐŽŵŵŽŶŝŶƚŚĞĨƵƚƵƌĞ͕ƉŽƉƵůĂƟŽŶƐŽĨĂŶŶƵĂůƉůĂŶƚƐƉĞĐŝĞƐŵĂLJĚĞĐůŝŶĞĂŶĚĐĞƌƚĂŝŶƉůĂŶƚƐƉĞĐŝĞƐĂƌĞůŝŬĞůLJƚŽďĞĐŽŵĞůŽĐĂůůLJĞdžƟŶĐƚ͘BUILT ENVIRONMENTNATURAL SYSTEMSCOMMUNITY RESILIENCEDROUGHT IMPACTSPage 647 of 669
8 RESILIENT SLOLagunaLakeStennerCreekBrizziolariCreekSanLuisObispoCreekStennerCreekPerfumoCreekSanLuisObispoCreekP e rfumo C r e e k
FroomCreekDavenportCreekEastForkSanLuisObispoCreekkLaLkgankeaP ePP rfruffmo C rC e e k SanLLuisObispspoCreekkkkab101ab101ÃÅ1ÃÅ227CCiittty oofSSaan LLLuuuuiyyyiiis yyyOOObbbbbbiiissspppo0 2,500 5,000FEETESRI World Imagery20200048.01 GIS 028Regionally-Defined DisadvantagedCommunitiesFEMA Flood Extent100-year Storm Event Flood Risk Zone500-year Storm Event Flood Risk ZoneSan Luis Obispo City LimitsFLOODINGCalifornia’s location, next to the Pacific Ocean, exposes the state to the atmospheric rivers. An Atmospheric River is a narrow corridor of concentrated moisture in the atmosphere. The presence of an Atmospheric River contributes to the frequency of “wet years”-years with above-average annual precipitation and large storms. The frequency of these large storm sequences over short timeframes is projected to increase noticeably in the future, with the size and frequency of events dependent on future levels of global greenhouse gas emissions. CHANGES IN FLOOD RISKPEAK STREAM FLOWƵƌŝŶŐƚŚĞϭϬͲLJĞĂƌƐƚŽƌŵĞǀĞŶƚ;ϭϬйĐŚĂŶĐĞŽĨŽĐĐƵƌƌŝŶŐŝŶĂŶLJLJĞĂƌͿ͕ƚŚĞŵĂdžŝŵƵŵŝŶƐƚĂŶƚĂ-ŶĞŽƵƐĂŵŽƵŶƚŽĨǁĂƚĞƌŇŽǁŝŶŐ;ƉĞĂŬƐƚƌĞĂŵŇŽǁͿƚŚƌŽƵŐŚƚŚĞŝƚLJ͛ƐƐƚƌĞĂŵƐǁŝůůŝŶĐƌĞĂƐĞŽŶĂǀĞƌĂŐĞďLJϯϯйďLJϮϬϳϬ͘WĞĂŬƐƚƌĞĂŵŇŽǁŝŶƚŚĞŝƚLJǁŝůůĂůƐŽINCREASE ON AVERAGE BY 38% BY 2070 FOR VERY LARGE STORM EVENTS ;ϭϬϬͲLJĞĂƌƐƚŽƌŵŽƌĂƐƚŽƌŵǁŝƚŚĂϭйĐŚĂŶĐĞŽĨŽĐĐƵƌƌŝŶŐŝŶĂŶLJLJĞĂƌͿ͘LARGE FLOODS,ŝƐƚŽƌŝĐĂůůLJ͕ƚŚĞŐƌĞĂƚĞƐƚŇŽŽĚŝŶŐŝŵƉĂĐƚƐŝŶŝƚLJŚĂǀĞŽĐĐƵƌƌĞĚĨƌŽŵATMOSPHERIC RIVͳER EVENTS WITH SEVERAL STORM EVENTS OCCURRING OVER SHORT TIME PERIODS ;ƚLJƉŝĐĂůůLJϮǁĞĞŬƐƚŽϯŵŽŶƚŚƐͿ͕ƐŝŵŝůĂƌƚŽƚŚĞ'ƌĞĂƚ&ůŽŽĚĞǀĞŶƚƐŽĨϭϴϲϭʹϭϴϲϮ͘ƐƚŽƌŵŽĨƐŝŵŝůĂƌŵĂŐŶŝƚƵĚĞŝƐŵŽƌĞůŝŬĞůLJƚŚĂŶŶŽƚƚŽŽĐĐƵƌĂƚůĞĂƐƚŽŶĐĞďĞƚǁĞĞŶϮϬϭϴĂŶĚϮϬϲϬ͘STORMWATER RUNOFF/ŶƚŚĞŵŝĚͲǁŝŶƚĞƌŵŽŶƚŚƐ͕ƚŚĞƐŽŝůƐŝŶƚŚĞ^ĂŶ>ƵŝƐKďŝƐƉŽƌĞĞŬtĂƚĞƌƐŚĞĚĂƌĞƌĞůĂƟǀĞůLJƐĂƚ-ƵƌĂƚĞĚĂŶĚŐĞŶĞƌĂƚĞƌƵŶŽīŵŽƌĞƋƵŝĐŬůLJ͘&ŽƌǀĞƌLJůĂƌŐĞƉƌĞĐŝƉŝƚĂƟŽŶĞǀĞŶƚƐ͕ƚŚĞĐĂƉĂĐŝƚLJŽĨƚŚĞǁĂƚĞƌƐŚĞĚƚŽĂďƐŽƌďŝŶĐŽŵŝŶŐƌĂŝŶĨĂůůĐĂŶďĞƋƵŝĐŬůLJĞdžĐĞĞĚĞĚ͕ĐĂƵƐŝŶŐůĂƌŐĞŝŶĐƌĞĂƐĞƐŝŶƐƚƌĞĂŵŇŽǁ͘&ůŽŽĚWůĂŝŶƐ;ϭϬϬͲĂŶĚϱϬϬͲLJĞĂƌƐƚŽƌŵƐͿĂŶĚŝƐĂĚǀĂŶƚĂŐĞĚŽŵŵƵŶŝƟĞƐŝŶƚŚĞŝƚLJŽĨ^ĂŶ>ƵŝƐKďŝƐƉŽPeak Stream Flow During Large StormsHISTORICFUTURE (BY 2070)Page 648 of 669
RESILIENT SLO 9FLOODING IMPACTSdŚĞŝƚLJ͛ƐƐƚŽƌŵǁĂƚĞƌŵĂŶĂŐĞŵĞŶƚƐLJƐƚĞŵŝƐĚĞƐŝŐŶĞĚƚŽŵĂŶĂŐĞƐƚŽƌŵǁĂƚĞƌƌƵŶŽīďĂƐĞĚŽŶƚŚĞƐŝnjĞŽĨŚŝƐƚŽƌŝĐƐƚŽƌŵĞǀĞŶƚƐ͘,ŽǁĞǀĞƌ͕ĐůŝŵĂƚĞĐŚĂŶŐĞŝƐƉƌŽũĞĐƚĞĚƚŽŝŶĐƌĞĂƐĞƚŚĞƐŝnjĞŽĨƐƚŽƌŵĞǀĞŶƚƐ͘LJϮϬϳϬ͕ƚŚĞŝŶĐƌĞĂƐĞĚƐƚƌĞĂŵŇŽǁĨƌŽŵĂϭϬϬͲLJĞĂƌƐƚŽƌŵĞǀĞŶƚ;ϭйĐŚĂŶĐĞŽĨŽĐĐƵƌƌŝŶŐŝŶĂŶLJLJĞĂƌͿǁŝůůůŝŬĞůLJŽǀĞƌǁŚĞůŵƚŚĞŝƚLJ͛ƐĞdžŝƐƟŶŐƐƚŽƌŵǁĂƚĞƌŝŶĨƌĂƐƚƌƵĐƚƵƌĞ͛ƐĂďŝůŝƚLJƚŽƐĂĨĞůLJĐŽŶƚƌŽůŇŽŽĚǁĂƚĞƌƐ͘dŚŝƐǁŽƵůĚĐĂƵƐĞŇŽŽĚǁĂƚĞƌƐƚŽďƌĞĂŬŽƵƚŽĨƚŚĞ^ĂŶ>ƵŝƐKďŝƐƉŽƌĞĞŬĐŚĂŶŶĞů͕ŇŽǁŝŶŐĂůŽŶŐƚŚĞ,ŝŐƵĞƌĂĂŶĚDĂƌƐŚ^ƚƌĞĞƚĐŽƌƌŝĚŽƌƚŽǁĂƌĚƐ^ƚĞŶŶĞƌƌĞĞŬĂƐǁĞůůĂƐŽƚŚĞƌůŽĐĂƟŽŶƐ͘>ĂƌŐĞŇŽŽĚŝŶŐĞǀĞŶƚƐŵĂLJĂůƐŽĐĂƵƐĞĚĂŵĂŐĞƚŽďƵŝůĚŝŶŐƐĂŶĚĚĞŐƌĂĚĞƚŚĞůŝĨĞƐƉĂŶŽĨƌŽĂĚǁĂLJƐĂŶĚďƌŝĚŐĞƐ͘tŚŝůĞĂůůĂƌĞĂƐŽĨƚŚĞŝƚLJǁŝƚŚŝŶŇŽŽĚƉůĂŝŶƐĂƌĞĂƚƌŝƐŬĨƌŽŵůĂƌŐĞƐƚŽƌŵĞǀĞŶƚƐ͕ƚŚĞƌĞŝƐƐŝŐŶŝĮĐĂŶƚŽǀĞƌůĂƉďĞƚǁĞĞŶƚŚĞƐĞŇŽŽĚƉůĂŝŶƐĂŶĚĂƌĞĂƐŝŶƚŚĞŝƚLJǁŝƚŚĚŝƐĂĚǀĂŶƚĂŐĞĚĐŽŵŵƵŶŝƟĞƐ;ĚĞĮŶĞĚďLJƚŚĞ^ĂŶ>ƵŝƐKďŝƐƉŽŽƵŶĐŝůŽĨ'ŽǀĞƌŶŵĞŶƚƐĂƐĚŝƐƉƌŽƉŽƌƟŽŶĂƚĞůLJďƵƌĚĞŶĞĚĂƌĞĂƐƚŚĂƚĂƌĞĞĐŽŶŽŵŝĐĂůůLJĚŝƐƚƌĞƐƐĞĚĂŶĚͬŽƌŚŝƐƚŽƌŝĐĂůůLJƵŶĚĞƌƌĞƉƌĞƐĞŶƚĞĚĂƐĂƉĂƌƚŽĨƚŚĞůŽĐĂůŐŽǀĞƌŶŵĞŶƚƉƌŽĐĞƐƐ͘Ϳ͘dŚŝƐŝŶĐůƵĚĞƐŶĞŝŐŚďŽƌŚŽŽĚƐĂůŽŶŐ^ŽƵƚŚ,ŝŐƵĞƌĂ^ƚƌĞĞƚŶĞĂƌ^ĂŶ>ƵŝƐKďŝƐƉŽƌĞĞŬĂŶĚƚŚĞ>ĂŐƵŶĂ>ĂŬĞŶĞŝŐŚďŽƌŚŽŽĚ͘&ůŽŽĚŝŶŐŵĂLJĂůƐŽĚŝƐƉƌŽƉŽƌƟŽŶĂƚĞůLJŝŵƉĂĐƚŚŽŵĞůĞƐƐƉŽƉƵůĂƟŽŶƐǁŚŽƐĞƐĞƩůĞŵĞŶƚƐĂƌĞŽŌĞŶŝŶŇŽŽĚƉůĂŝŶƐĂŶĚĂƌĞůĞƐƐĂďůĞƚŽƚƌĂŶƐƉŽƌƚƚŚĞŵƐĞůǀĞƐŽƵƚŽĨŇŽŽĚĂƌĞĂƐĚƵƌŝŶŐƐƚŽƌŵĞǀĞŶƚƐ͘/ŶĐƌĞĂƐĞƐŝŶůĂƌŐĞƐƚŽƌŵĞǀĞŶƚƐĐĂŶƌĞƐƵůƚŝŶŝŶĐƌĞĂƐĞĚĞƌŽƐŝŽŶŽĨĐƌĞĞŬďĂŶŬƐĂŶĚŝŶĐƌĞĂƐĞĚƐĞĚŝŵĞŶƚĂƟŽŶŝŶǁĂƚĞƌǁĂLJƐĂŶĚǁĂƚĞƌďŽĚŝĞƐůŝŬĞ>ĂŐƵŶĂ>ĂŬĞ͘͞tĞƚLJĞĂƌƐ͕͟ǁŝƚŚĂďŽǀĞĂǀĞƌĂŐĞĂŶŶƵĂůƉƌĞĐŝƉŝƚĂƟŽŶ͕ĐĂŶĂůƐŽŝŶĐƌĞĂƐĞƉůĂŶƚŐƌŽǁƚŚƌĞƐƵůƟŶŐŝŶŝŶĐƌĞĂƐĞĚĨƵĞůĨŽƌǁŝůĚĮƌĞƐĚƵƌŝŶŐƐƵďƐĞƋƵĞŶƚĚƌLJLJĞĂƌƐ͘BUILT ENVIRONMENTClimate change is projected to in-crease the intensity (total rainfall) of storm events in the City, compromis-ing the ability of the City’s stormwa-ter management system to manage rainfall during large storm events. Climate-informed flood modeling predicts that by 2070 the flood plains for the City’s 100-year and 500-year storm events will expand, increasing the risk for properties in or near the City’s existing floodplains. FLOODINGNATURAL SYSTEMSCOMMUNITY RESILIENCEPage 649 of 669
10 RESILIENT SLOWILDFIREWildfire risk is determined by several factors, such as wind, available wildfire fuel (i.e., plants), fuel moisture levels, topography, past wildfire suppression, and the presence of the wildland-urban interface (i.e., development and homes in and around natural areas). Increasing temperatures and changes to rainfall patterns caused by climate change will increase the probability of wildfires oc-curring in San Luis Obispo County. These changes will also increase the size of fires when they do occur. CHANGES IN WILDFIRE RISKWILDFIRE FREQUENCYLJĂƐĞĂƌůLJĂƐϮϬϯϱ͕ƚŚĞůŝŬĞůŝŚŽŽĚƚŚĂƚŽŶĞŽƌŵŽƌĞŵĂũŽƌǁŝůĚĮƌĞƐ;ǁŝůĚĮƌĞƐďƵƌŶŝŶŐϵϴϴĂĐƌĞƐŽƌŵŽƌĞͿǁŝůůŽĐĐƵƌŝŶ^ĂŶ>ƵŝƐKďŝƐƉŽŽƵŶƚLJŽǀĞƌĂƚĞŶͲLJĞĂƌƉĞƌŝŽĚǁŝůů INCREASE FROM 20%, HISTORICALLY, TO 30%. SIZE OF WILDFIRESLJĂƐĞĂƌůLJĂƐϮϬϯϱ͕ƚŚĞĂǀĞƌĂŐĞƐŝnjĞŽĨǁŝůĚ-ĮƌĞƐ;ǁŝůĚĮƌĞƐďƵƌŶŝŶŐϵϴϴĂĐƌĞƐŽƌŵŽƌĞͿŝŶ^ĂŶ>ƵŝƐKďŝƐƉŽŽƵŶƚLJ͕ǁŚĞŶƚŚĞLJĚŽŽĐĐƵƌ͕ǁŝůůINCREASE BY 16%͘,ŝƐƚŽƌŝĐĂůůLJ͕ƚŚĞĂǀĞƌ-ĂŐĞǁŝůĚĮƌĞƐŝnjĞŝŶƚŚĞŽƵŶƚLJǁĂƐϮϮ͕ϴϱϮĂĐƌĞƐĂŶĚďLJϮϬϯϱƚŚĞĂǀĞƌĂŐĞǁŝůĚĮƌĞŝƐƉƌŽũĞĐƚĞĚƚŽďĞϮϲ͕ϱϬϵĂĐƌĞƐ͘WILDFIRE LOCATIONůƚŚŽƵŐŚĂƌĞĂƐƐƵƌƌŽƵŶĚŝŶŐƚŚĞŝƚLJǁŝůůďĞĂƚŝŶĐƌĞĂƐĞĚƌŝƐŬĨƌŽŵǁŝůĚĮƌĞƐ͕ƚŚĞůĂƌŐĞƐƚĂŶ-ƟĐŝƉĂƚĞĚĐŽƵŶƚLJǁŝĚĞŝŶĐƌĞĂƐĞƐŝŶƚŚĞƐŝnjĞŽĨǁŝůĚĮƌĞƐŝŶƚŚĞĨƵƚƵƌĞǁŝůůŽĐĐƵƌŝŶƚŚĞ^ĂŶƚĂ>ƵĐŝĂtŝůĚĞƌŶĞƐƐĂŶĚƚŚĞ>ĂWĂŶnjĂDŽƵŶƚĂŝŶƌĂŶŐĞůŽĐĂƚĞĚŝŶƚŚĞƐŽƵƚŚͲĐĞŶƚƌĂůƉŽƌƟŽŶƐŽĨƚŚĞŽƵŶƚLJ͘ab101ab101ÃÅ1ÃÅ227CCiittty oofSSaan LLLLLuuuuuuiyyyiiis yyyOOObbbbbiiissspppo0 2,500 5,000FEETESRI Wold Imagery20200048.01 GIS 021Regionally-Defined DisadvantagedCommunitiesFire Hazard Severity ZonesVery HighHighModerateSan Luis Obispo City Limits&ŝƌĞ,ĂnjĂƌĚ^ĞǀĞƌŝƚLJŽŶĞƐ;Ăů&ŝƌĞĚĞƐŝŐŶĂƚĞĚͿĂŶĚŝƐĂĚǀĂŶƚĂŐĞĚŽŵŵƵŶŝƟĞƐŝŶƚŚĞŝƚLJŽĨ^ĂŶ>ƵŝƐKďŝƐƉŽProbability of Major Wildfire in SLO County over 10 YearsHISTORICFUTURE (BY 2035)major wildfire = wildfires burning 988 acres or morePage 650 of 669
RESILIENT SLO 11WILDFIREWILDFIRE IMPACTSdŚĞŝƚLJŝŶĐůƵĚĞƐĂƌĞĂƐƚŚĂƚŚĂǀĞďĞĞŶĚĞƐŝŐŶĂƚĞĚĂƐsĞƌLJ,ŝŐŚ&ŝƌĞ,ĂnjĂƌĚ^ĞǀĞƌŝƚLJŽŶĞƐďLJĂů&ŝƌĞ;Ğ͘Ő͕͘ĂƌĞĂƐĂƚŝŶĐƌĞĂƐĞĚƌŝƐŬŽĨƉƌŽƉĞƌƚLJĚĂŵĂŐĞ͕ůŽƐƐŽĨůŝĨĞͿ͘dŚĞƐĞĂƌĞĂƐŝŶĐůƵĚĞƚŚĞŶĞŝŐŚďŽƌŚŽŽĚĂĚũĂĐĞŶƚƚŽƚŚĞ/ƌŝƐŚ,ŝůůƐEĂƚƵƌĂůZĞƐĞƌǀĞ͕ĂƌĞĂƐƚŽƚŚĞĞĂƐƚŽĨ^ĂŶ>ƵŝƐƌŝǀĞŝŶƚŚĞŶŽƌƚŚŽĨƚŚĞŝƚLJ͕ĂŶĚƐŵĂůůƉŽƌƟŽŶƐŽĨƚŚĞ&ĞƌƌŝŶŝZĂŶĐŚKƉĞŶ^ƉĂĐĞĂƌĞĂ͘dŽĂǀŽŝĚǁŝůĚĮƌĞŝŐŶŝƟŽŶƐ͕ĞůĞĐƚƌŝĐŝƚLJƵƟůŝƟĞƐŚĂǀĞďĞŐƵŶŝŵƉůĞŵĞŶƟŶŐWƵďůŝĐ^ĂĨĞƚLJWŽǁĞƌ^ŚƵƚŽīƐ;Ğ͘Ő͕͘ƉƌĞĞŵƉƟǀĞƉŽǁĞƌƐŚƵƚŽīƐͿĚƵƌŝŶŐƉĞƌŝŽĚƐŽĨŚŝŐŚǁŝůĚĮƌĞƌŝƐŬ͘WƵďůŝĐ^ĂĨĞƚLJWŽǁĞƌ^ŚƵƚŽīƐĂƌĞƉƌŽũĞĐƚĞĚƚŽŝŶĐƌĞĂƐĞŝŶƚŚĞĨƵƚƵƌĞ͕ůĞĂǀŝŶŐŝƚLJƌĞƐŝĚĞŶƚƐĂŶĚďƵƐŝŶĞƐƐĞƐǁŝƚŚŽƵƚƉŽǁĞƌǁŚĞŶƚŚĞLJĚŽŽĐĐƵƌ͘ƐĂƌĞŐŝŽŶĂůĞŵƉůŽLJŵĞŶƚĐĞŶƚĞƌŝŶƚŚĞŽƵŶƚLJ͕ƚŚĞŝƚLJĞdžƉĞƌŝĞŶĐĞƐĂůĂƌŐĞŝŶŇƵdžŽĨĚĂŝůLJǀŝƐŝƚŽƌƐ͘ ǀĂĐƵĂƟŽŶĞǀĞŶƚƐĚƵƌŝŶŐĚĂLJƟŵĞŚŽƵƌƐǁŽƵůĚďĞĐŚĂůůĞŶŐŝŶŐďĞĐĂƵƐĞŽĨŚŝŐŚŶƵŵďĞƌƐŽĨĚĂŝůLJǀŝƐŝƚŽƌƐ͘ džƉŽƐƵƌĞƚŽǁŝůĚĮƌĞƐŵŽŬĞ͕ƉĂƌƟĐƵůĂƌůLJĞdžƉŽƐƵƌĞĨŽƌǀƵůŶĞƌĂďůĞƉŽƉƵůĂƟŽŶƐ;ŝ͘Ğ͕͘ĞůĚĞƌůLJ͕LJŽƵƚŚ͕ĐŽŵŵƵŶŝƟĞƐŽĨĐŽůŽƌ͕ŝŶĚŝǀŝĚƵĂůƐƵŶĚĞƌůLJŝŶŐŚĞĂůƚŚĐŽŶĚŝƟŽŶƐͿ͕ŝƐĂƉƵďůŝĐŚĞĂůƚŚƌŝƐŬ͘^ŵŽŬĞĞdžƉŽƐƵƌĞĐĂŶƌĞƐƵůƚŝŶǁŽƌƐĞŶŝŶŐƌĞƐƉŝƌĂƚŽƌLJƐLJŵƉƚŽŵƐ͕ŝŶĐƌĞĂƐĞĚƌĂƚĞƐŽĨĐĂƌĚŝŽƌĞƐƉŝƌĂƚŽƌLJĞŵĞƌŐĞŶĐLJǀŝƐŝƚƐ͕ŚŽƐƉŝƚĂůŝnjĂƟŽŶƐ͕ĂŶĚĞǀĞŶĚĞĂƚŚ͘EĞŝŐŚďŽƌŚŽŽĚƐƚŚĂƚĂƌĞƉĂƌƟĐƵůĂƌůLJǀƵůŶĞƌĂďůĞƚŽǁŝůĚĮƌĞŝŵƉĂĐƚƐŚĂǀĞƌĞůĂƟǀĞůLJůĂƌŐĞĞůĚĞƌůLJĂŶĚLJŽƵƚŚƉŽƉƵůĂƟŽŶƐĂŶĚůŽĐĂƟŽŶƐŶĞĂƌĮƌĞŚĂnjĂƌĚĂƌĞĂƐ͘dŚĞŝŶĐƌĞĂƐŝŶŐĨƌĞƋƵĞŶĐLJŽĨĮƌĞƐŝŶŽƉĞŶƐƉĂĐĞĂƌĞĂƐĐĂŶĂīĞĐƚůŽĐĂůĞĐŽƐLJƐƚĞŵƐ͘^ƉĞĐŝĮĐĂůůLJĐĂƵƐŝŶŐĐŽĂƐƚĂůƐĂŐĞƐŚƌƵďƐĂŶĚĐŚĂƉĂƌƌĂůƚŽƐŚŝŌƚŽŐƌĂƐƐĞƐŽǀĞƌƟŵĞ͘>ĂƌŐĞƌĂŝŶĨĂůůĞǀĞŶƚƐŝŶǁŝůĚĮƌĞͲĂīĞĐƚĞĚĂƌĞĂƐĐĂŶĐĂƵƐĞƉŽƐƚͲǁŝůĚĮƌĞƌƵŶŽīĂŶĚĚĞďƌŝƐŇŽǁƐ;Ğ͘Ő͕͘ŵƵĚƐůŝĚĞƐǁŝƚŚĚĞďƌŝƐͿƉŽƚĞŶƟĂůůLJĐĂƵƐŝŶŐůŽƐƐŽĨůŝĨĞ͕ƉƌŽƉĞƌƚLJĚĂŵĂŐĞ͕ďůŽĐŬŝŶŐƌŽĂĚǁĂLJƐ͕ĂŶĚŝŶĐƌĞĂƐŝŶŐƐĞĚŝŵĞŶƚĂƟŽŶŝŶǁĂƚĞƌǁĂLJƐ͘BUILT ENVIRONMENTIncreases in the frequency and size of wildfires in San Luis Obispo County may affect the City in different ways depending on the location and ex-tent of the fires. Wildfires occurring in or surrounding the City will have a much larger impact on the community including potential loss of life, prop-erty damage, emergency evacuation events, and impacts on local air qual-ity. Structures in the wildland-urban interface are at increased risk from wildfire impacts and increased risk for fire ignition. NATURAL SYSTEMSCOMMUNITY RESILIENCEPage 651 of 669
12 RESILIENT SLOEXTREME HEATThe City has a mild Mediterranean climate. Climate change is projected to in-crease both minimum and maximum annual average temperatures in the City and increase the prevalence of extreme heat events. CHANGES IN EXTREME HEATEXTREME HEAT DAYSLJĂƐĞĂƌůLJĂƐϮϬϯϱ͕ƚŚĞŝƚLJŝƐůŝŬĞůLJƚŽĞdžƉĞ-ƌŝĞŶĐĞAPPROXIMATELY 10 EXTREME HEAT DAYS ;ŵĂdžŝŵƵŵƚĞŵƉĞƌĂƚƵƌĞĂďŽǀĞϴϵ͘ϲΣ&ŽƌŚŝŐŚĞƌͿƉĞƌLJĞĂƌĐŽŵƉĂƌĞĚƚŽϰĚĂLJƐŚŝƐƚŽƌŝĐĂů-ůLJ͘HEAT WAVE EVENTSLJĂƐĞĂƌůLJĂƐϮϬϯϱ͕ƚŚĞŝƚLJĐŽƵůĚĞdžƉĞƌŝĞŶĐĞĂŵĂdžŝŵƵŵŽĨTHREE CONSECUTIVE EXTREME HEAT DAYS IN THE FUTUREĐŽŵƉĂƌĞĚƚŽĂŵĂdžŝŵƵŵŽĨƚǁŽĐŽŶƐĞĐƵƟǀĞŚĞĂƚĚĂLJƐŚŝƐƚŽƌ-ŝĐĂůůLJ͘TIMING OF EXTREME HEAT/ŶƚŚĞĨƵƚƵƌĞ͕ŵŽƌĞĞdžƚƌĞŵĞŚĞĂƚĚĂLJƐĂŶĚHEAT WAVE EVENTS WILL OCCUR EARLIER IN THE YEAR;ƉƌŝůƚŚƌŽƵŐŚDĂLJͿǁŝƚŚƚŚĞŵŽƐƚƐĞǀĞƌĞĞǀĞŶƚƐŽĐĐƵƌƌŝŶŐŝŶƚŚĞŚŝƐƚŽƌŝĐĂůůLJŚŽƚŵŽŶƚŚƐŽĨ^ĞƉƚĞŵďĞƌĂŶĚKĐƚŽďĞƌ͘ab101ab101ÃÅ1ÃÅ227CCiittty oofSSaan LLLuuuuuuiyyyiiis yyyOOObbbbbiiissspppo0 2,500 5,000FEETESRI World Imagery20200048.01 GIS 032Regionally-Defined DisadvantagedCommunitiesUrban Heat Island SeverityMildMild to ModerateModerateModerate to HighSevere"Tree LocationSan Luis Obispo City Limits&ŝƌĞ,ĂnjĂƌĚ^ĞǀĞƌŝƚLJŽŶĞƐ;Ăů&ŝƌĞĚĞƐŝŐŶĂƚĞĚͿĂŶĚŝƐĂĚǀĂŶƚĂŐĞĚŽŵŵƵŶŝƟĞƐŝŶƚŚĞŝƚLJŽĨ^ĂŶ>ƵŝƐKďŝƐƉŽAnnual Extreme Heat Days (90° F or above)HISTORICFUTURE (BY 2035)Page 652 of 669
RESILIENT SLO 13EXTREME HEATEXTREME HEAT IMPACTS'ƌĞĂƚĞƌĞdžƚƌĞŵĞŚĞĂƚǁŝůůŝŶĐƌĞĂƐĞƚŚĞƵƌďĂŶŚĞĂƚŝƐůĂŶĚĞīĞĐƚ͘dŚĞƵƌďĂŶŚĞĂƚŝƐůĂŶĚĞīĞĐƚŝƐƚŚĞƉŚĞŶŽŵĞŶŽŶŽĨƵƌďĂŶĂƌĞĂƐďĞŝŶŐƐŝŐŶŝĮĐĂŶƚůLJǁĂƌŵĞƌƚŚĂŶƐƵƌƌŽƵŶĚŝŶŐƌƵƌĂůĂƌĞĂƐďĞĐĂƵƐĞŽĨŚƵŵĂŶĂĐƟǀŝƚLJĂŶĚůĂŶĚͲƵƐĞƉĂƩĞƌŶƐŝŶƚŚĞďƵŝůƚĞŶǀŝƌŽŶŵĞŶƚ͘,ŝŐŚĞƌƚĞŵƉĞƌĂƚƵƌĞƐĂŶĚĞdžƚƌĞŵĞŚĞĂƚǁŝůůƌĞƐƵůƚŝŶŝŶĐƌĞĂƐĞĚĞŶĞƌŐLJĚĞŵĂŶĚĨŽƌĐŽŽůŝŶŐŝŶƚŚĞŝƚLJ͘dŚĞŐƌĞĂƚĞƐƚŝŵƉĂĐƚƐŵĂLJďĞŝŶĂƌĞĂƐǁŚĞƌĞƚŚĞƵƌďĂŶŚĞĂƚŝƐůĂŶĚĞīĞĐƚŝƐƐƚƌŽŶŐĞƌ͕ĂŶĚŝŶŽůĚĞƌ͕ůĞƐƐĞŶĞƌŐLJͲĞĸĐŝĞŶƚŚŽŵĞƐ͘ džƚƌĞŵĞŚĞĂƚǁŝůůĂůƐŽƉůĂĐĞŝŶĐƌĞĂƐĞĚƐƚƌĞƐƐŽŶƚŚĞĞůĞĐƚƌŝĐŝƚLJŐƌŝĚƉŽƚĞŶƟĂůůLJůĞĂĚŝŶŐƚŽŵŽƌĞĞůĞĐƚƌŝĐŝƚLJĚŝƐƌƵƉƟŽŶƐ;Ğ͘Ő͕͘ďƌŽǁŶŽƵƚƐĂŶĚďůĂĐŬŽƵƚƐͿ͘/ŶĐƌĞĂƐĞĚƚĞŵƉĞƌĂƚƵƌĞƐĐĂŶĐĂƵƐĞŚĞĂƚƐƚƌŽŬĞ͕ŚĞĂƚĞdžŚĂƵƐƟŽŶ͕ŚĞĂƚƐLJŶĐŽƉĞ͕ĂŶĚŚĞĂƚĐƌĂŵƉƐ͘sƵůŶĞƌĂďůĞƉŽƉƵůĂƟŽŶƐ͕ƐƵĐŚĂƐƚŚŽƐĞϲϱŽƌŽůĚĞƌ͕ŝŶĨĂŶƚƐĂŶĚĐŚŝůĚƌĞŶ͕ĂŶĚŝŶĚŝǀŝĚƵĂůƐǁŝƚŚĐŚƌŽŶŝĐŚĞĂůƚŚĐŽŶĚŝƟŽŶƐ͕ĂƌĞĂƚŚŝŐŚĞƌƌŝƐŬĨƌŽŵŚĞĂƚͲƌĞůĂƚĞĚŝŵƉĂĐƚƐ͘ƌĞĂƐŽĨƚŚĞĐŝƚLJƉĂƌƟĐƵůĂƌůLJǀƵůŶĞƌĂďůĞƚŽĞdžƚƌĞŵĞŚĞĂƚŚĂǀĞĂŚŝŐŚƉĞƌĐĞŶƚĂŐĞŽĨĞůĚĞƌůLJ͕ĚŝƐĂďůĞĚ͕ŽƌůŽǁͲŝŶĐŽŵĞƌĞƐŝĚĞŶƚƐ͘/ŶĐƌĞĂƐĞƐŝŶĞdžƚƌĞŵĞŚĞĂƚĂƌĞƉƌŽũĞĐƚĞĚƚŽďĞŵŽƌĞƐĞǀĞƌĞŝŶƚŚĞ^ĂŶ:ŽĂƋƵŝŶsĂůůĞLJĂŶĚƐŽƵƚŚĞƌŶĂůŝĨŽƌŶŝĂƚŚĂŶŝŶ^ĂŶ>ƵŝƐKďŝƐƉŽ͘dŚŝƐŵĂLJŝŶĐƌĞĂƐĞƚŚĞŶƵŵďĞƌŽĨƚŽƵƌŝƐƚƐŽƌŶĞǁƉĞƌŵĂŶĞŶƚƌĞƐŝĚĞŶƚƐĐŽŵŝŶŐƚŽƚŚĞŝƚLJƚŽĞƐĐĂƉĞƚŚĞŚĞĂƚ͘dŚŝƐ͕ŝŶƚƵƌŶ͕ŵĂLJƉůĂĐĞŝŶĐƌĞĂƐĞĚƉƌĞƐƐƵƌĞŽŶŝƚLJƌĞƐŽƵƌĐĞƐĂŶĚƐĞƌǀŝĐĞƐ͘ŚĂŶŐĞƐŝŶƚĞŵƉĞƌĂƚƵƌĞĂŶĚĞdžƚƌĞŵĞŚĞĂƚĂƌĞůŝŬĞůLJƚŽŶĞŐĂƟǀĞůLJŝŵƉĂĐƚƚŚĞŝƚLJ͛ƐƚƌĞĞƐ͘dĞŵƉĞƌĂƚƵƌĞĐŚĂŶŐĞƐŵĂLJĂůƐŽŝŵƉĂĐƚƚŚĞĂŐƌŝĐƵůƚƵƌĞĂŶĚǀŝƟĐƵůƚƵƌĞŝŶĚƵƐƚƌŝĞƐ͘dŚŝƐŵĂLJƌĞƐƵůƚŝŶĚĞĐƌĞĂƐĞƐŝŶǁŝŶĞĂŶĚǀŝŶĞLJĂƌĚͲďĂƐĞĚƚŽƵƌŝƐŵ͕ŝŶĚƵƐƚƌŝĞƐƚŚĂƚƚŚĞŝƚLJƌĞůŝĞƐŽŶĨŽƌƌĞǀĞŶƵĞĂŶĚĞŵƉůŽLJŵĞŶƚŽƉƉŽƌƚƵŶŝƟĞƐ͘BUILT ENVIRONMENTFuture increases in extreme heat days and heat waves will affect the City’s natural systems, built environment, and especially community members. Certain populations are at higher risk of extreme heat including residents over the age of 65, infants and chil-dren, individuals with chronic health conditions (e.g., cardiovascular dis-ease, asthma), low-income popula-tions, and outdoor workers. NATURAL SYSTEMSCOMMUNITY RESILIENCEPage 653 of 669
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SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 1COMMUNITY SAFETY &RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS The adaptation strategies included here are a set of options to be considered for inclusion in the City’s Safety and Resiliency Element update. The strategies focus on helping the City prepare for the short-term (2021-2050) and more long-term (2050-2099) impacts of cli-mate change that have been included in the Climate Change Hazards and Vulnerabili-ties Report (Hazards Report). This set of adaptation strategies responds to the impacts from climate-related hazards discussed in the Hazards Report and works to build upon the com-prehensive set of plans and initiatives the City has already undertaken to reduce risk from natural hazards that will be exacerbated by climate change.STRATEGY DEVELOPMENT AND OUTREACH PROCESSAs part of the development of these adaptation strategies, a set of meetings were held to gain feedback and brainstorm ideas through a facilitated process. The strategies include in this document reflect the feedback received at these meetings as well as internal discussions with City staff and the Resilient SLO project team. Outreach meetings included: •Four Working Group Meetings focused on key topics included in the Resilient SLO project (i.e., Natural Systems, Built Environment, Community Resilience, and Environmental Justice)•The Adapting to a Changing Climate Workshop – Strategies for a more Resilient SLO public workshop being held on July 22, 2021•A meeting of the Resilience Roundtable, a community-led advisory body for the Resilient SLO project, to further develop a list of adaptation strategy options ORGANIZATION OF THE ADAPTATION STRATEGIESThe adaptation strategies in this memo are organized into the four main hazard categories included in the Hazards Report. They are: Extreme Heat, Wildfire, Drought, and Flood. There are also several additional sets of strategies not focused on particular hazards but are in-tended to address multiple hazards and focus on other aspects of resilience. These addition-al strategy categories include: Resilient City Operations, Equity and Environmental Justice, and Social and Economic Resilience. Each strategy includes working strategy title and a brief description of the strategy. Under each strategy category, the strategies are organized by which aspect of the City is general-ly focusing on based on the three focus areas for the Resilient SLO project. Definitions of the three focus areas are included below:NATURAL SYSTEMS•Natural Systems – This category includes systems or system components of the natural environment (e.g., forests and grasslands, flora and fauna, stream health) in the City and the surrounding region that are critical to overall ecosystem health. • Built Environment – This category includes the physical assets that comprise the City’s built environment (e.g., roadway network, buildings, utility systems, stormwater management system) that are critical to supporting normal community functions in the City. • Community Resilience – This category includes human-focused systems that provide essential services to residents and visitors in the City and are critical to maintaining normal community functions (e.g., economic activity, healthcare system, schools). COMMUNITY RESILIENCEBUILT ENVIRONMENTPage 655 of 669
2 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONSTEMPERATURE & EXTREME HEATRESILIENCE STRATEGIES>/Dd ͳ^DZdEdhZ>Z ^KhZ DE' D EdΈEdhZ>^z^d D^ΉIntegrate climate projections regarding changes in average temperatures and extreme heat into updates of the City’s natural resource planning documents including the City’s set of Open NATURAL SYSTEMSSpace Conservation Plans, as they are updated, as well as the City’s Open Space Conservation Guidelines. Integrate Climate-Smart Pest Management Practices into the City’s Open Space Conservation Guidelines with consideration of how climate change is going to affect pest control and invasive species.hWd d, /dz͛^^dZ ddZ ^D^d Z>/^ddKWZ WZ &KZ/EZ ^ ^/Ed DW ZdhZ E ydZ D , d s Ed^ΈEdhZ>^z^d D^ΉConduct analysis and incorporate into the City’s Urban Forest Master Plan and, if necessary, update the City’s Street Trees Master List to prepare for increases in minimum and maximum temperatures and extreme heat events and corresponding drought and fire risk, identifying which trees will be most vulnerable to climate impacts and which species will thrive during future increases in temperature. Ensure updated Street Trees Master List does not include highly combustible trees that increase fire risk in the City. Communicate the results of the analysis to help City residents prepare for impacts on trees on private property. DKE/dKZKK>Ws D Edd ,EK>K'z&KZd, /dzΈh/>d Es/ZKED EdΉMonitor and pilot cool pavement technologies that may reduce the urban heat island effect being generated from the City’s pavement surfaces focusing on large surface parking lots. Identify urban BUILT ENVIRONMENTheat island hotspots in the City using data from The Trust for Public Land and other sources regarding the urban heat island effect in the City and implement a cool pavement pilot project in key areas of the City to review results, including up-front capital costs and ongoing maintenance requirements. Research and adopt new standards for new development projects, as appropriate, to use high-albedo or cool pavements for surface parking lots. Monitor roadway standards issued by both the state and federal government in order to be able to implement cool pavement standards on City roadways./DW> D Ed>/Dd ͳ^DZdhZE, d/^>E^dZd 'zdKD/d/'d d, hZE, d/^>E && dE^^K/d /DWd^Έh/>d Es/ZKED EdΉDevelop and implement appropriate strategies for the City to use aspects of the built environment to mitigate the projected increasing impacts from the urban heat island effect. This should include a strategy to maintain and enhance the City’s urban tree canopy and other vegetative features to help reduce the urban heat island effect while accounting for the effect of shifting average minimum and maximum temperatures on sensitive tree species and vegetation. Strategies should also include potential updates to the City’s development standards to reduce the urban heat island effect in new development. Strategies could include: • Integrate the Climate-Smart Green Infrastructure Strategy with regular updates to the City’s Capital Improvement Program and Foundational Action Natural Solutions 2.1 in the City’s Climate Action Plan which focuses on preparing the City’s first Urban Forest Master Plan by 2021 and planting and maintain 10,000 new trees by 2035.• Review and update Section 12.38.090 “Landscaping Standards“ in the City’s Municipal Code and other design guidelines to incorporate strategies to increase shading of buildings and parking lots to mitigate the urban heat island effect.• Review and update City development standards, where appropriate, to include building and site design features that mitigate the urban heat island effect including reflective roofing, solar carports Page 656 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 3/EKZWKZd >/Dd Z ^/>/ E & dhZ ^/EdKd, /dz͛^>/Dd d/KEW>Eh/>/E'Z dZK&/dWZK'ZDΈh/>d Es/ZKED EdΉAs part of the City’s building retrofit program (Foundational Actions, Buildings 2.1) included the Climate Action Plan, climate resilience retrofit features to help residents prepare for the impacts of climate change (e.g., extreme heat, wildfires, and wildfire smoke). Incorporate projections on future energy demand associated with shifts in maximum and minimum temperatures as well as increase the frequency and severity of extreme heat events. This work should include conducting a gap analysis to identify portions of the City’s housing stock that are not equipped with air-conditioning or other cooling systems to address the projected increases in temperature and extreme heat events. As part of the building retrofit program, include proactive efforts (i.e., incentives, matching funds) to retrofit or assist with retrofitting the identified housing stock with climate resiliency features including:• Adequate climate control equipment (e.g., HVAC) and air conditioning heat pumps,• Weatherization and energy efficiency improvements to address increases in extreme heat and annual average maximum temperatures, • Reflective roofing, green walls/roof, shade trees, and other features to reduce energy demand for cooling, and • Home hardening improvements to protect against wildfire. COMMUNITY RESILIENCE s >KWKDDhE/dzKK>KE ^E dtKZ<ΈKDDhE/dzZ ^/>/ E ΉWork with community organizations, faith-based organizations, businesses, local government entities in including SLO County, and other institutions to develop a Community Cool Zone Network comprised of air-conditioned spaces conveniently located throughout the City that can be opened during heat wave events to help prevent heat-related illness for vulnerable populations (e.g., elderly, youth, homeless, residents without air conditioning). Support network participants to conduct energy efficiency and building decarbonization improvements consistent with the City’s TEMPERATURE & EXTREME HEATClimate Action Plan. Prioritize opening cool zone locations in areas with identified heat-vulnerable populations and disadvantaged communities. Assess feasibility and efficacy of providing transportation options to the cooling network location to elderly residents and transit-dependent populations. Explore funding mechanisms to support businesses and institutions for their participation in the Community Cool Zones Network. KEhdKDWZ , E^/s KDDhE/dzͳ> KhdZ ,dKWZ WZ sh>E Z> WKWh>d/KE^&KZ, dts s Ed^ΈKDDhE/dzZ ^/>/ E ΉUse information from the City’s Resilient SLO Hazards Report that identifies areas in the City with vulnerable populations (e.g., linguistically isolated households, elderly, youth, homeless, individuals with chronic health conditions) to conduct targeted outreach to these neighborhoods and areas in the City. Increase education and training opportunities for residents to prepare for extreme heat events, with a prioritization on vulnerable populations and businesses and institutions that house and/or support vulnerable populations. Components of the outreach should include:• Work with community organizations and other institutions to establish a network of Community Resilience Ambassadors who can support outreach efforts, educate residents on climate preparedness, and connect residents to existing resources and organizations. • Work with community organizations and the San Luis Obispo County Health Department to provide additional resources and training to staff working with elderly populations on how to prevent health-related impacts. Work with community organizations and schools to help mitigate the impacts of extreme heat and heat wave events on youth. Educate and train staff working with youth populations on how to prevent health-related impacts from extreme heat. • Continually assess the effectiveness of the City’s public information and education efforts during heat wave events. • As part of the City’s support of the Micro-Communities Collaborative, establish a “Neighbors Helping Neighbors” campaign to support a peer-to-peer network of individuals who can check in and provide resources to neighbors who are vulnerable to extreme heat impacts. Page 657 of 669
4 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS/EKZWKZd E ydZ D , dWZKdKK>/EdKd, E ydhWd K&d, /dz͛^KDWZ , E^/s /^^d Z> Z^,/WW>EE/E>h /Ed, /dz͛^>K>,ZD/d/'d/KEW>EΈKDDhE/dzZ ^/>/ E ΉAs part of the next update of the City’s Comprehensive Disaster Leadership Plan (i.e., Emergency Operations Plan), incorporate a protocol for emergency operations during extreme heat events in the City. Identify extreme heat thresholds which, if exceeded, would trigger the opening of cooling centers in the City as well as emergency response efforts from appropriate City departments (e.g., Police Department, Fire Department). Coordinate emergency response efforts in strategy Heat 8 regarding heat-related community outreach with this strategy. TEMPERATURE & EXTREME HEATPage 658 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 5WILDFIREADAPTATION STRATEGIES/DW> D Edd, /dz͛^s ' dd/KEDE' D EdW>EΈEdhZ>^z^d D^ΉContinue to implement the City’s Vegetation Management Plan, conducting fuel reduction projects at the 12 large open space lands included in the plan, using vegetation management techniques NATURAL SYSTEMSappropriate for each open space including manual vegetation removal; tree removal; mechanical treatment, prescribed burning, livestock grazing, and chemical treatment. Update the Vegetation Management Plan, as needed, to incorporate regulations regarding vegetation management plan, new best practices, and new funding opportunities for vegetation management projects. Work with Northern Chumash Tribal Council and other tribal bodies to incorporate, where appropriate, Traditional Ecological Knowledge approaches to vegetation management in the City. Policy Measures which focus on the four key policy areas of community education, fuels management, planning, and emergency response preparedness. Update the CWPP, as needed, to incorporate new best practices, funding opportunities, new legislation regarding wildfire protection, and other wildfire protection planning resources.sK/t/>&/Z ,Z^^^K/d t/d,E t s >KWD Ed/Ed, /dzΈh/>d Es/ZKED EdΉAvoid locating future development projects in the wildland-urban interface or in areas of the City located within a Cal Fire designated Fire Hazard Severity Zone. Ensure that new development projects include adequate measures to minimize fire hazards while remaining in compliance with housing laws regarding objective design standards and discretionary /DW> D Edd, /dz͛^KDDhE/dzt/>&/Z WZKd d/KEW>EΈh/>d Es/ZKED EdΉContinue to implement the City’s Community Wildfire Protection Plan (CWPP) to reduce wildfire risk in the City’s wildland-urban interface including implementation of the CWPP Tactical BUILT ENVIRONMENTreview. Ensure that new development projects include adequate measures to minimize fire hazards. Implement the following set of policies to reduce wildfire risk associated with new development: New Development Policies• Require all new development located within any Cal Fire designated Fire Hazard Severity Zone to: о Meet or exceed the State’s Fire Safe Regulations (title 14, CCR, division 1.5, chapter 7, subchapter 2, articles 1-5 commencing with section 1270) and Fire Hazard Reduction Around Buildings and Structures Regulations (title 14, CCR, division 1.5, chapter 7, subchapter 3, article 3 commencing with section 1299.01). о Include designs to minimize pockets or peninsulas or islands of flammable vegetation within a development. о Include additional access roads, where feasible, to ensure adequate access for emergency equipment and civilian evacuation concurrently. All requirements and any deviations will be at the discretion of the Fire Code Official. о Meet or exceed the California Building Code for Materials and Construction Methods for Exterior Wildfire Exposure (Title 24, part 2, Chapter 7A). о For all remodeled or rebuilt structures, require projects to meet current ignition resistance construction codes included in the State’s Fire Safe Regulations. Planning Policies• Locate, when feasible, new essential public facilities outside of high fire risk areas, including, but not limited to, hospitals and health care facilities, emergency shelters, emergency command centers, and emergency communications facilities, or identifying construction methods or other methods to minimize damage if these facilities are located in a state responsibility area or very high fire hazard severity zone. • Update local zoning and subdivision codes to designate wildfire hazard overlay zones and associated conditional use, site development standards, and design criteria to mitigate wildfire hazards and reduce risks to new development within the overlay zones.Page 659 of 669
6 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS о Fire protection plans should address wildland fuel transition zones surrounding the development and include the following components: » Provisions for the maintenance of vegetation within the subdivision to reduce wildfire risk » Requirements for hardening of structures to mitigate fire risk that meets or exceed the California Building Code » Landscaping and defensible space design around a proposed structure that reduces wildfire risk. • Promote the following risk reduction measures in future land use planning efforts in the City: о Use wildfire risk analysis resources such as the Cal Fire’s Fire and Resource Assessment Program (FRAP) data in future housing site constraints analyses to ensure future land use planning avoids locating new housing in high wildfire risk areas. о Promote the use of clustered development patterns for subdivisions that require less fire suppression resources and are easier to defend during wildfire events compared to large-lot single family homes (Moritz and Butsic 2020). s >KWWK>/zdK>/D/dKEͳ^dZ dWZ</E'/E,/',t/>&/Z Z/^<Z ^hZ/E'Z &>'z^Έh/>d Es/ZKED EdΉDevelop policy and update the City’s Municipal Code to restrict on-street parking in high wildfire risk areas in the City during Red Flag Days to ensure full access for fire trucks and emergency vehicles and increase roadway accessibility during evacuation events. Work with the City Fire Department and other departments to identify streets and neighborhoods that are at increased wildfire risk using the Cal Fire Fire Hazard Severity Zones, Wildland Urban Interface Areas identified by the City, or another internal process. Conduct community outreach to neighborhoods affected by the policy and provide detailed information on how and when the parking restrictions will be implemented. /DW> D Edt/>>EͳhZEͳ/Ed Z& & E^/> ^W E,KD ,Z E/E'WZK'ZD&KZ y/^d/E' s >KWD EdΈh/>d Es/ZKED EdΉImplement a program to assist homeowners, landlords, and business owners in improving the defensible space for structures in or near the very high fire hazard severity zones. The program will serve to connect participants to contractors with experience in developing or improving and home hardening improvements (e.g., fire-safe building materials, fire resistant home vent upgrades) to help expedite improvements for existing development in the City. The program will seek funding to supplement the costs associated with defensible space improvements, prioritizing low-income participants and elderly or disabled residents who would not be able to implement defensible space improvements on their own. The program would be developed and administered in close collaboration with the City’s Fire Department and Cal Fire to ensure appropriate standards for defensible space are implemented as part of the program./EZ ^ KWWKZdhE/d/ ^&KZdd Zz^dKZ' E E Z'z/E W E E &KZZ ^/ E Eh^/E ^^ ^dKD/d/'d /DWd^&ZKDWh>/^& dzWKt Z^,hdK&&^Έh/>d Es/ZKED EdΉThrough the City’s Community Development Department, proactively provide the information on funding resources and financing options for the installation of battery storage systems for existing residential and non-residential developments, prioritizing opportunities for essential services such as hospitals, grocery stores, pharmacies, and other essential businesses. Develop a streamlined permitting process, including appropriate CEQA exemptions, for the installation of small- and large-scale battery storage systems in existing residential and nonresidential development as well as providing applicants information on financing options through 3CE’s Energy Resilience Programs. WILDFIREPage 660 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 7WILDFIRECOMMUNITY RESILIENCE s >KWE/DW> D Edt/>&/Z ^DK< WZKd d/KEKhdZ ,^dZd 'zΈKDDhE/dzZ ^/>/ E ΉDevelop and implement a Wildfire Smoke Protection Outreach Strategy to help protect City’s residents and visitors from poor air quality caused by wildfire smoke. Work with the San Luis Obispo Air Pollution Control District to conduct a comprehensive outreach campaign focused on educating residents on how to protect themselves and their homes from wildfire smoke impacts. Prioritize outreach campaigns to populations who are vulnerable to poor air quality and those who work with the population (e.g., elderly care nurses and assistances, teachers), conducting educational events at convenient locations for these residents. Specific topics could include: • General tips to avoiding wildfire smoke impacts• Education on proper use of N95 respirators• Publishing and sharing location of local Resilience Center with residence• Preparing homes for wildfire smoke events and development of “clean rooms”• Proper use of air conditioning and climate control during wildfire smoke events• Behaviors to reduce indoor air quality impacts (e.g., avoid vacuuming, using gas-powered appliances) Page 661 of 669
8 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONSDROUGHTRESILIENCE STRATEGIESNATURAL SYSTEMSKEhdKDWZ , E^/s E>z^/^K&E yd E ΈϮϬͳz ZΉZKh',d^ EZ/KKEd, /dz͛^td Z^hWW>zΈEdhZ>^z^d D^ΉAs part of the State’s Fourth Climate Change Assessment, State agencies (e.g., Department of Water Resources, California Public Utility Agency) conducted an extended (20-year) drought scenario assessment to identify what impacts would occur on the state’s water supply. Using data from the Cal-Adapt tool and other available resources, the City should conduct an extended drought scenario analysis to consider the effects on the City’s water supply and water demand. Research indicates that an extended drought scenario similar to the one included Fourth Climate Change Assessment could occur within the 21st century (Pierce et al. 2018) and, therefore, should be an important consideration for the City’s long-term water management planning efforts. KEd/Eh dK/DW> D Edd, /dz͛^hZEtd ZDE' D EdW>EEtd Z^,KZd' KEd/E' EzW>EΈEdhZ>^z^d D^ΉContinue to implement the City’s Urban Water Management Plan, and Water Shortage Contingency Plan and update these plans as needed to account for future regulations and requirements. The City has taken considerable steps to assess and prepare for a long-term drought scenario through these planning efforts, including an assessment of how climate change may affect the City’s water supply. As part of future updates to the Urban Water Management Plan, research the feasibility of developing a network of rainwater harvesting facilities to support aquatic systems and groundwater recharge. KEd/Eh dK/DW> D Edd, /dz͛^Z z> td ZD^d ZW>EEhWd ͕^E Έh/>d Es/ZKED EdΉContinue to implement the City’s Recycled Water Master Plan and continuing planning efforts for future increases in demand for BUILT ENVIRONMENTrecycled water as part of future development projects in the City including specific plan areas (e.g., Margarita Area, Orcutt Area, Airport Areas, San Luis Ranch, and Froom Ranch). Continue to allocate available funds and seek new funding opportunities to implement the capital improvement projects (Recycled Water Master Plan Chapter 7: Capital Improvement Plan) needed to meet the increased demand for recycled water for existing and new development. KE^/ Z/EKZWKZd/KEK&td Zͳ &&// EdWW>/E Z dZK&/d^^WZdK&d, /dz͛^&KZd,KD/E'h/>/E'Z dZK&/dWZK'ZDΈh/>d Es/ZKED EdΉConsider including options for water-efficient appliance retrofits as part of the City’s forthcoming building retrofit program being implemented as part of the Climate Action Plan. Work with the City’s Utilities Department to integrate current resources and programs regarding water conservation and energy-efficient appliance retrofits into the building retrofit program. The building retrofit program can also serve to highlight the energy conservation benefits of the reduced residential and commercial water use. Page 662 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 9DROUGHT ^d>/^,W ZW/dtd Zh^ Z hd/KEdZ' ddK ,/ s zϮϬϮϱ͘h^ hd/KEEKhdZ ,dKWZKDKd td ZKE^ Zsd/KEWZd/ ^Etd Z &&// EzZ dZK&/d^&KZZ ^/ Ed/>EEKEZ ^/ Ed/>h/>/E'^Έh/>d Es/ZKED EdΉUsing information in the City’s 2020 Urban Water Management Plan, establish an aggressive per capita water use reduction target to be achieved by 2025 and track yearly progress on achieving the goal. Use a suite of existing and new strategies to achieve the target through water conversation education and financial incentives for water efficiency retrofits for residential and nonresidential properties. Water conservation strategies should include: • Continue the City’s Toilet Retrofit Inspection/Verification and expand to include other low-flow appliance retrofits including faucets, showerheads, and information on low water use appliances (e.g., dishwashers, washing machines)• Work with community organizations and contractors to educate the public about the benefits and water conservation potential of rainwater catchment systems and greywater systems • Conduct community outreach to educate citizens on current levels of water use by end-use in the City and water conservation tips to reduce household and business water waste/DW> D Ed͞^,&KZ'Z^^͟>tEZ W> D EdWZK'ZDt/d,^hWWKZd&ZKDKDDhE/dzKZ'E/d/KE^E>E^W/E'KEdZdKZ^Έh/>d Es/ZKED EdΉDesign and implement a “Cash for Grass” lawn replacement program to help residents and businesses reduce outdoor water use and promote native climate-smart landscaping improvements. Price lawn replacement on a square-footage basis that effectively attracts participants. Work with SLO County to adopt lessons learned and best practices from the County program. Work with community organizations to promote the program and track implementation progress. Page 663 of 669
10 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONSgreen stormwater infrastructure, permeable parking lots, and pavement) to help offset climate impacts on the City’s stormwater management system from climate change. Incorporate green infrastructure improvements.FLOODINGADAPTATION STRATEGIESWZ/KZ/d/ >/Dd ͳ^DZd'Z E/E&Z^dZhdhZ ^dZd '/ ^&KZ&>KKDE' D EdΈEdhZ>^z^d D^ΉTo account for future changes in large storm events (50-, 100-, and 500-year storm events), prioritize the use of green infrastructure strategies (compared to grey infrastructure strategies) to manage NATURAL SYSTEMSfuture flood risk exacerbated by climate change. Work with public and landowners upstream of waterways passing through the City (e.g., Stenner Creek, San Luis Obispo Creek) to manage stormwater runoff through sustainable land conservation practices (e.g., conservation easements) that achieve multiple objectives for the City (e.g., carbon farming, land conservation, flood management). As part of this effort the City should, support and build upon Policy 10.2.2 B of the City’s Conservation and Open Space Element which states, “Natural resources such as wetlands, flood plains, recharge zones, riparian areas, open space, and native habitats should be identified, preserved and restored as valued assets for flood protection, water quality improvement, groundwater recharge, habitat, and overall long-term water resource sustainability.”E>z WK^dͳt/>&/Z Z/^&>Kt/DWd^ΈEdhZ>^z^d D^ΉConduct a detailed assessment to identify key impact areas in the City from a post-wildfire debris flow scenario and the implications this scenario would have on stormwater runoff during larger storm events. Establish a protocol for conducting an emergency assessment of post-fire debris-flow hazards in coordination with the United State Geologic Survey to identify key areas of risk from specific wildfire events that occur in or near the City. Develop a set of pre-disaster mitigation measures to be implemented to help mitigate impacts from post-wildfire debris flow events. Mitigation measures could include: • Rapid reforestation of wildfire-affected areas susceptible to debris flow runoff to stabilize soils;• Communication and coordination with residents and businesses located within potential impact areas from post-wildfire debris flow events; and • Development of analysis techniques to predict debris flow events based on rainfall and moisture conditions.assessment to account for future changes in precipitation patterns and flood risk. Incorporate future changes in precipitation patterns into the City’s Drainage Design Manual to ensure that future development in the City can properly accommodate changes in runoff from small and large storm events. Incorporate climate-informed flood risk modeling in all flood management-related capital improvement projects in the current Waterway Management Plan as well as future projects. As part of the update process, develop targets to offset the increase in stormwater runoff from existing residential and nonresidential land uses through green infrastructure approaches (e.g., rain gardens, rainwater catchment barrels, >/Dd ͳ/E&KZD td ZtzDE' D EdW>EΈh/>d Es/ZKED EdΉDuring the next update of the City’s Waterway Management Plan, incorporate the future climate-informed flood risk modeling that was developed as part of the City’s climate change vulnerability BUILT ENVIRONMENT GREEN INFRASTRUCTURE “Green infrastructure” encompasses natural features, such as forests and wetlands, that provide similar or complementary flood-management benefits as engineered infrastructure. While engineered infrastructure can degrade rivers and the values they provide, green infrastructure tends to support a diverse array of other benefits. A sustainable and resilient approach to flood-risk management will deploy a mix of green and engineered infrastructure solutions, tailored to specific challenges and objectives. The Nature Conservancy, 2014Page 664 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 11FLOODINGCOMMUNITY RESILIENCE s >KWE /',KZ,KKZ /E ^^W>E^EWZKDKd &>KKWZ WZ E ^^ hd/KEΈKDDhE/dzZ ^/>/ E ΉWork with community organizations to develop neighborhood readiness plans for areas of the City at increased risk of flooding. Identify priority (i.e., flood-prone) neighborhoods to serve as pilot plans for this strategy. Work with San Luis Obispo County Office of Emergency Services, community organizations, and regional partners to develop neighborhood readiness plans. Use the Neighborhood Readiness planning process to increase flood preparedness education, awareness of existing City resources (e.g., carless collection points for evacuation points), and training opportunities for City residents and business owners. Incorporate strategy to work with and support evacuation of unhoused populations living in floodplains into Neighborhood Readiness Plans. KEd/Eh dKhd/>/ Z hEE/ ^/Ed, /dz͛^&>KKDE' D Ed^z^d DΈh/>d Es/ZKED EdΉExplore opportunities to add redundancy to the City’s existing stormwater and flood management systems to mitigate impacts from increased storm intensities, as needed, using detention basins, green infrastructure (e.g., bio-swales, floodplain management through conservation easements) (Hettiarachchi et al. 2018). Considering the uncertainty in the timing of changes in large storm events, design flood management system redundancies to serve multiple purposes that add value to the community (e.g., detention basins that serve as parks or recreation areas). yW>KZ &>KK Z>ztZE/E'^z^d D&KZ^E>h/^K/^WKZ <Work with San Luis Obispo County to explore the feasibility and benefits of developing a flood monitoring and early warning system to provide alerts to residents during large storm events. Gather information from similar communities that have early warning systems to learn about costs, benefits, and best practices for developing a flood early warning system for the City.Page 665 of 669
12 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONSCOMMUNITY RESILIENCE/DW> D EdKDDhE/dzZ ^/>/ E Ed ZWZ/^ &hEΈKDDhE/dzZ ^/>/ E ΉDevelop and administer a Community Resilience Enterprise Fund that provides micro-grants to individuals or community organizations to implement projects that support social cohesion as EQUITY & EJEQUITY AND ENVIRONMENTAL JUSTICE (EJ) STRATEGIESit relates to climate change impacts and disaster recovery. The grants would be distributed through an application process in which applicants would propose projects, explaining why the outcome of the project would increase social cohesion and increase resilience to the anticipated impacts of climate change or help to repair historical inequities that have left certain populations more vulnerable to the impacts of climate change. Grants would be administered would develop criteria to evaluate applications and grant awardees with a focus on providing grants that focus on protecting the most vulnerable populations (i.e., low-income, minority, or elderly populations). E^hZ >>Z ^/>/ E ^dZd '/ ^Z /DW> D Ed /E:h^dE Yh/d> DEE ZΈKDDhE/dzZ ^/>/ E ΉIdentify key community organizations working with underserved and historically disadvantaged communities and ensure these organizations and representatives from historically disadvantaged play a substantive role in the strategy implementation process. Implement the following practices to ensure equitable strategy implementation: • Ensure community outreach and education opportunities focused on strategy implementation include multi-lingual options for both written materials and in-person engagement. Include demographic surveys as part of community outreach events to ensure that participants are representative of the demographic makeup (e.g., race, age, ethnicity) of the City’s population as a whole. • As strategies are implemented, ensure that the goal of the strategy aligns with community needs by providing opportunities for community organizations and other stakeholders to review strategy details before implementation. Use equity metrics included in the State’s Adaptation Planning Guide, or similar metrics, to develop a Equity and Environmental Justice Project Checklist to be used during the design and development of City-led programs and capital improvement projects to ensure they are implemented equitably and, where appropriate, historically disadvantaged communities are prioritized in receiving the benefits of the project. • Ensure that procedural equity, distributional equity, and structural equity impacts are all considered in the implementation of resilience strategies.• Continue to use existing resources (listed below) that identify disadvantaged communities in the City and prioritize community outreach to these communities during implementation of relevant strategies. о California Department of Water Resources Disadvantaged Communities Mapping Tool о Public Health Alliance of Southern California’s California Healthy Places Index о Environmental Protection Agency’s Environmental Justice Screening Tool о Office of Environmental Health Hazard Assessment CalEnviroScreen Tool Page 666 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 13RESILIENT CITYRESILIENT CITY OPERATION STRATEGIES^hWWKZdd, /dz͛^hZZ EdZKEE hdZ>/dz&/>/d/ ^W>EE yW>KZ d, & ^//>/dzK&> Eͳ E Z'zD/ZK'Z/&KZ/dz&/>/d/ ^Έh/>d Es/ZKED EdΉContinue supporting the City’s current Carbon Neutral City Facilities s >KWEKWd>/Dd Z ^/>/ Ez, <>/^d&KZE t s >KWD EdWZK: d^/Ed, /dzdKD/d/'d d, /DWd^K&>/Dd ͳZ >d ,Z^Έh/>d Es/ZKED EdΉSimilar to the City’s GHG Emissions Analysis Compliance Checklist, develop and adopt a Climate Resiliency Checklist to ensure that new residential and nonresidential development in the City is designed and built to withstand the future impacts of climate change. Incorporate all appropriate policies related to new development that are included in the City’s General Plan Safety Element into the checklist. Items in the Climate Resiliency Checklist should be objective and comply with all relevant housing laws to eliminate discretionary review. Checklist items could include: • Updated energy design standards that incorporate future changes in annual average minimum and maximum temperatures• Additional batter storage requirements for certain types of development to mitigate impacts from future utility disruptions• Defensible space and home hardening requirements for development located in high wildfire risk areas designated by the City• Additional building design or site plan requirements to mitigate flood-related impacts in areas with current or future flood risk• Additional building design or landscaping requirement to reduce water consumption in new development /DW> D Ed>/Dd ͳ/E&KZD D Z' EzKW Zd/KE^W>EE/E'Έh/>d Es/ZKED EdΉDuring the City’s next update of the Comprehensive Disaster Leadership Plan, incorporate climate projections and climate impact data for the Climate Change Hazards and Vulnerabilities Report into the planning process and analyze future staffing and resource requirements to adequately address the future frequency and intensity of climate related hazards in the City. Develop protocols for novel climate-related hazards that the City has previously experienced including prolonged heat wave events and wildfire smoke impacts. plan. As part of this plan, if appropriate, conduct a feasibility study for developing a clean energy microgrid for key City facilities to provide clean back-up power during utility disruptions (e.g., Public Safety Power Shutoffs or other disruptions) as well as providing local solar power to City facilities non-emergency use during the day. Ensure that the feasibility study includes the following details to allow for development of a City microgrid, if deemed feasible: MICROGRIDAs defined by the U.S. Department of Energy Microgrid Exchange Group, a “microgrid is a group of interconnected loads and distributed energy resources within clearly defined electrical boundaries that acts as a single controllable entity with respect to the grid. A microgrid can connect and disconnect from the grid to enable it to operate in both grid-connected or island-mode.” • A review of regulatory and operational considerations • A conceptual shovel-ready design of the technical components for a fully connected microgrid and an islandable solar + storage system• A phasing strategy and procurement plan for implementation • An operational strategy that includes governance and cybersecurity• Key considerations for operation of the microgrid during short-term and long-utility disruptions BUILT ENVIRONMENTSeek funding sources including the California Energy Commissions Electric Program Investment Charge (EPIC) Program and the Pacific Gas and Electric Community Microgrid Enablement Program (CMEP) to conduct a feasibility study. Page 667 of 669
14 SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS yW>KZ KWWKZdhE/d/ ^dK yWE ^^dKWK^dͳ/^^d ZZ Ks ZzZ ^KhZ ^ΈKDDhE/dzZ ^/>/ E ΉExplore opportunities to expand access to post-disaster recovery resources for residents and businesses (e.g., recovery funding, recovery services). Establish metrics to help assess effectiveness /Ed 'Zd >/Dd WZK: d/KE^/EdK/dzh/>/E'E E'/E Z/E'^dEZ^EZKhd/E /E&Z^dZhdhZ D/Ed EE Έh/>d Es/ZKED EdΉBegin the process of evaluating and updating the City’s building and engineering standards to account for future changes in key climate variables (e.g., changes in size of large storm events, maximum daily temperatures) that are likely to affect critical infrastructure. Use data from the Climate Change Hazards and Vulnerabilities Report, the Cal-Adapt tool, and supplemental climate projection data and research to inform the updates to the City’s standards update process. Use an climate-informed adaptive management approach to continually monitor the performance of the updated building and engineering standards against the observed changes in climate variables, adjusting standards as need to match future changes in these variables caused by climate change. /EKZWKZd >/Dd Z/^</EdKd, /dz͛^W/d>/DWZKs D EdWZK: d^Έ/WΉW>EE/E'WZK ^^Έh/>d Es/ZKED EdΉAssess existing infrastructure systems vulnerable to changes in key climate variables (e.g., flooding, extreme heat) and incorporate upgrades to critical infrastructure in the City’s Capital Improvement Projects (CIP) planning process. Identify key pieces of existing infrastructure that are likely to be compromised by climate impacts and prioritize these upgrades as part of the City CIP process. Use data from the Climate Change Hazards and Vulnerabilities Report, the Cal-Adapt tool, and supplemental climate projection data and research to inform an appropriate list of infrastructure upgrades. establish a protocol to remove these barriers and expedite rebuilding for a post-disaster recovery scenario. This strategy aligns with Policy 9.11 “Disaster Recovery” in the City’s existing Safety Element. /DW> D Ed>KE'ͳd ZD^dZd 'zdK/EZ ^ /dz^d&&W/dzdKZ ^^>/Dd ,E' E/DW> D EdWdd/KE^dZd '/ ^ΈKDDhE/dzZ ^/>/ E ΉUse information from the Resilient SLO Capacity Building Assessment to identify key gaps in the City’s knowledge of climate adaptation planning and how to integrate the topic into their work. Establish a 1-3 strategy and workplan to increase City staff capacity to fully integrate climate change adaptation as key component of their work for appropriate departments and staff. Assess progress towards increasing staff capacity to address climate change on an annual or bi-annual basis and adjust strategy accordingly based on results and new information and guidance regarding climate adaptation planning. Establish the City’s Green Team as the official working group to help implement the suite of climate adaptation strategies included in the City’s Safety Element Update, identifying representatives from key City departments to lead champion climate adaptation in those departments. /Ed 'Zd Z '/KE>K>>KZd/KE/EdKd, /dz͛^>/Dd Wd/KEW>EE/E'ΈKDDhE/dzZ ^/>/ E ΉIntegrate regional collaboration as a key component of the City’s climate adaption planning strategy, recognizing the regional nature of climate impacts and climate adaptation strategies. Continue the City’s active participation in the Central Coast Climate Collaborative (4C) by sharing lessons learned, strategy collaboration opportunities, and regionally-relevant data included in the Climate Change Hazards and Vulnerabilities Report. Consistently communicate and provide updates on adaptation strategy implementation to the general public and key partners including the San Luis Obispo County, other incorporated cities in the County, and community organizations. Identify members of the City’s Green Team to serve as city liaisons for regional adaptation-focused organizations and key regional climate adaptation planning efforts. COMMUNITY RESILIENCEin post-disaster recovery efforts including metrics to ensure that post-disaster recovery resources are allocated equitably and consider historically disadvantaged communities. Assess potential barriers for rehabilitation and rebuilding in post-disaster situations and RESILIENT CITYPage 668 of 669
SAFETY & RESILIENCY ELEMENT CLIMATE ADAPTATION STRATEGY OPTIONS 15tKZ<KDDhE/dzKZ'E/d/KE^͕&/d,ͳ^ KZ'E/d/KE^͕EKd, Z/E^d/dhd/KE^dK ^d>/^,E dtKZ<K&>/Dd Z ^/>/ E ,h^&KZ>/Dd ͳZ >d ,Z s Ed^Έh/>d Es/ZKED EdΉWork community organizations, faith-based organizations, and SSOCIAL & ECONOMICRESILIENCE STRATEGIES^hWWKZd KEKD/Z ^/>/ E &KZ>K>h^/E ^^ ^dKD/d/'d &/^>/DWd^&ZKD>/Dd ,E' ΈKDDhE/dzZ ^/>/ E ΉUse information in the City’s Climate Change Hazards and Vulnerabilities Report to identify key economic sectors that are vulnerable to impacts from climate-related hazards (e.g., tourism) and develop a strategy to diversify the City’s economy to avoid overreliance on economic sectors that are vulnerable to climate impacts. Work with the San Luis Obispo Chamber of Commerce to identify businesses and local industries already being affected by climate-related impacts (e.g., drought, wildfire smoke, extreme heat) and identify opportunities to help support affected industries. ^hWWKZd/E/s/h>E,Kh^ ,K>Z ^/>/ E EWZ WZ E ^^dKd, /DWd^K&>/Dd ,E' ΈKDDhE/dzZ ^/>/ E ΉWork with community organizations, the San Luis Obispo County Office of Emergency Services, and other key stakeholders to educate individuals and households about strategies to increase preparedness for emergency events and climate-related impacts. Strategies could include: • Creating emergency kits emergency supply kits for homes, cars, and at work locations• Creating personal emergency funds for short- and long-term emergency events• Information on mental health and support services for post-disaster recBUILT ENVIRONMENTother institutions to develop a network of conveniently located Climate Resilience Hubs including a mix of public facilities, community centers, businesses, and community-oriented facilities (e.g., churches, synagogues, mosques). Ensure the chosen facilities are equipped to provide shelter to vulnerable populations during other emergency events such as periods of poor air quality from wildfire smoke, utility disruptions, flooding events, or other climate-related hazards (CDC n.d.). Ensure the Climate Resilience Center is centrally located near transit stops to provide public transit access. COMMUNITY RESILIENCE/ Ed/&z>/Dd Wdd/KE&hE/E'^KhZ ^E ^d>/^,>/Dd Z ^/>/ E &hEΈKDDhE/dzZ ^/>/ E ΉEstablish a Climate Resilience Fund as part of the City’s General Fund to support the implementation of climate adaptation strategies identified in the City’s Safety Element. Supplement the Climate Resilience Fund by identifying and pursuing funding and financing opportunities for specific climate adaptation strategies. Identify high-priced climate adaptation strategies or capital improvement projects and research the feasibility of financing these efforts through green bonds or similar financing mechanisms. ^^ ^^d, && d^K&>/Dd ,E' KE&KK/E^ hZ/dz/Ed, /dzWork with community organizations (e.g., SLO Food Bank) and the SLO County Health Department to assess potential impacts of climate change on food prices and food insecurity in the City. Partner with community organizations to address food insecurity including opportunities to support food recovery efforts as part of implementation of Senate Bill 1383 to reduce food waste and associated greenhouse gas emissionsPage 669 of 669