HomeMy WebLinkAbout06-14-2016 Item 21 Council Reading File - Compiled CC Draft UWMP
2015 Urban Water
Management Plan
This plan was adopted on June 14, 2016
pursuant to
San Luis Obispo City Council Resolution
No. #### (2016 series).
San Luis Obispo City Council
Jan Marx, Mayor
Dan Carpenter
John Ashbaugh
Carlyn Christianson
Dan Rivoire
Plan Prepared by:
City of San Luis Obispo, Utilities Department
879 Morro Street
San Luis Obispo, CA. 93401
Carrie Mattingly, Director
Aaron Floyd, Deputy Director, Water Division
Jennifer Metz, Utilities Projects Manager
Mychal Boerman, Acting Utilities Services Manager
2015 Urban Water Management Plan
i
Contents
CHAPTER 1. Introduction
1.1 Urban Water Management Planning Act ................................................................................... 1-1
1.2 Agency Coordination .................................................................................................................. 1-2
1.3 Public Participation And Plan Adoption ................................................................................... 1-3
1.4 Plan Implementation ................................................................................................................... 1-3
1.5 Standarized Tables ..................................................................................................................... 1-3
1.6 Compliance Checklist ................................................................................................................. 1-3
1.7 Abbreviations & Acronyms ........................................................................................................ 1-4
CHAPTER 2. Service Area and Water System Description
2.1 Service Area Description ........................................................................................................... 2-1
2.2 Service Area Population Projection and Other Demographic Information ........................... 2-1
2.3 Water System Description ......................................................................................................... 2-3
2.4 Required UWMP Standardized Tables .................................................................................... 2-12
CHAPTER 3. Current and Projected Water Demand
3.1 Water Use By Sector ................................................................................................................... 3-1
3.2 Demand Sector Definitions ........................................................................................................ 3-1
3.3 Water Loss and Unbilled Authorized Consumption Types .................................................... 3-2
3.4 Estimating Future Water Savings .............................................................................................. 3-2
3.5 Low Income Housing .................................................................................................................. 3-2
3.6 Baseline and Target For Water Use Reduction By 2020 ......................................................... 3-3
3.7 Updating Calculations from 2010 UWMP.................................................................................. 3-3
3.8 Baseline Periods ......................................................................................................................... 3-4
3.9 Service Area Population ............................................................................................................. 3-5
3.10 Gross Water Use ......................................................................................................................... 3-5
3.11 Baseline Per Capita Water Use .................................................................................................. 3-6
3.12 2015 and 2020 Targets ................................................................................................................ 3-7
3.13 Compliance Daily Oer Capita Water Use .................................................................................. 3-8
3.14 Required UWMP Standardized Tables .................................................................................... 3-10
3.15 Required SB X7-7 Standardized Tables .................................................................................. 3-12
CHAPTER 4. Water Sources
4.1 Salinas Reservoir ........................................................................................................................ 4-1
4.2 Whale Rock Reservoir ................................................................................................................ 4-2
4.3 Nacimiento Reservoir ................................................................................................................. 4-4
4.4 Groundwater ................................................................................................................................ 4-5
4.5 Water Supply Summary .............................................................................................................. 4-7
4.6 Transfers And Exchange Opportunities ................................................................................... 4-7
4.7 Future Water Projects ................................................................................................................. 4-8
4.8 Desalinated Water Opportunities .............................................................................................. 4-8
4.9 Required UWMP Standardized Tables ...................................................................................... 4-9
CHAPTER 5. Recycled Water
5.1 Wastewater Collection, Treatment and Disposal ..................................................................... 5-1
5.2 Current Recycled Water Use ...................................................................................................... 5-2
5.3 Future System Expansion .......................................................................................................... 5-4
5.3 Recycled Water Program Incentives ......................................................................................... 5-5
5.5 Seasonal Surplus ........................................................................................................................ 5-6
5.6 Potable Reuse ............................................................................................................................. 5-7
5.7 Required UWMP Standardized Tables ...................................................................................... 5-8
2015 Urban Water Management Plan
ii
CHAPTER 6. Water Supply Reliability
6.1 Salinas and Whale Rock Reservoirs ......................................................................................... 6-1
6.2 Recycled Water ........................................................................................................................... 6-1
6.3 Nacimiento Reservoir ................................................................................................................. 6-2
6.4 Groundwater ................................................................................................................................ 6-2
6.5 Water Quality ............................................................................................................................... 6-3
6.6 Water Supply Reliability Analysis ............................................................................................. 6-3
6.7 Required UWMP Standardized Tables ...................................................................................... 6-5
CHAPTER 7. Water Conservation & Demand Management Measures
7.1 History .......................................................................................................................................... 7-1
7.2 Conservation Program Highlights ............................................................................................. 7-1
7.3 Water Waste Prevention Ordinances ........................................................................................ 7-2
7.4 Metering ....................................................................................................................................... 7-3
7.5 Conservation Pricing .................................................................................................................. 7-3
7.6 Public Education and Outreach ................................................................................................. 7-3
7.7 Programs to Assess and Manage Distribution System Real Loss ........................................ 7-3
7.8 Water Conservation Program Coordination and Staffing Support ........................................ 7-4
7.9 Other Demand Management Measures..................................................................................... 7-4
CHAPTER 8. Water Shortage Contingency Plan
8.1 Water Shortage Determination .................................................................................................. 8-1
8.2 Water Shortage Repsonse ......................................................................................................... 8-2
8.3 Water Shortage Stages ............................................................................................................... 8-2
8.4 Revenue and Expenditure Impacts ........................................................................................... 8-9
8.5 Catastrophic Water Supply Interruption ................................................................................. 8-10
8.6 Minimum Supply Next Three Years ......................................................................................... 8-10
8.7 Required UWMP Standardized Tables .................................................................................... 8-11
2015 Urban Water Management Plan
iii
List of Tables
TABLE 1: San Luis Obispo Climate ....................................................................................................... 2-1
TABLE 2: City Population ........................................................................................................................ 2-1
TABLE 3: Top Employers ........................................................................................................................ 2-2
TABLE 4: Current and Projected Water Use by Sector ........................................................................ 3-1
TABLE 5: Common Water Loss and Unbilled Authorized Consumption Types ............................... 3-2
TABLE 6: Water Demand for Lower Income Housing Units ................................................................ 3-3
TABLE 7: Target Method 3, Hydrologic Region Goals ......................................................................... 3-3
TABLE 8: Baseline Period Ranges ......................................................................................................... 3-5
TABLE 9: Annual Gross Water Use ........................................................................................................ 3-6
TABLE 10: Daily Per Capita Water Use .................................................................................................. 3-7
TABLE 11: Confirmed 2020 Targets ....................................................................................................... 3-8
TABLE 12: 2015 Interim Target ............................................................................................................... 3-8
TABLE 13: Baselines and Targets Summary ........................................................................................ 3-8
TABLE 14: 2015 SB X7-7 Compliance .................................................................................................... 3-9
TABLE 15: Average GPCD ...................................................................................................................... 3-9
TABLE 16: City Wells ............................................................................................................................... 4-6
TABLE 1 7: City Groundwater Production .............................................................................................. 4-6
TABLE 1 8: 2015 Actual Water Supplies ................................................................................................. 4-7
TABLE 1 9: Actual and Projected Water Supplies ................................................................................. 4-7
TABLE 20: Transfer and Exchange Opportunities ............................................................................... 4-8
TABLE 21: Recycled Water Usage, 2011-2015 ...................................................................................... 5-3
TABLE 22: 2015 Influent Flow and Recycled Water Availability ......................................................... 5-4
TABLE 23: Potential Future Recycled Water Use ................................................................................. 5-5
TABLE 24: 2010 UWMP Recycled Water Use Projection Compared to 2015 Actual Deliveries ....... 5-5
TABLE 2 5: Methods to Encourage Recycled Water Use ..................................................................... 5-7
TABLE 2 6: Water Quality Current and Projected Water Supply Impacts ........................................... 6-3
TABLE 2 7: Basis of Water Year Data ..................................................................................................... 6-4
TABLE 2 8: Supply and Demand Comparison – Normal Year .............................................................. 6-4
TABLE 2 9: Single Dry Year Supply and Demand Comparison ........................................................... 6-5
2015 Urban Water Management Plan
iv
List of Tables (continued)
TABLE 30: Multiple Dry Year Supply and Demand Comparison......................................................... 6-5
TABLE 31: Water Demand Management Measures Demand Management Measures and California
Urban Water Conservation Council BMP Names .............................................................. 7-2
TABLE 3 2: Water Shortage Response Stages Quick Reference Guide ............................................. 8-4
TABLE 3 3: Minimum Supply Next Three Years .................................................................................. 8-10
List of Figures
FIGURE 1: Multi-Source Water Supply .................................................................................................. 2-5
FIGURE 2: Potable Water Pressure Zones ............................................................................................ 2-7
FIGURE 3: Water Distribution Facility Locations ................................................................................. 2-9
FIGURE 4: 2005 to 2015 Annual per Capita Water Demand ................................................................. 3-5
FIGURE 5: Water Reuse Master Plan Area and Distribution System ................................................. 5-3
Appendices
Appendix I: Notification to Agencies, Public Hearing & Plan Adoption .............................................. I-1
Appendix II: Water Resource Status Reports (2011-2015) ................................................................... II-1
Appendix III: Department of Water Resources Checklist ................................................................... III-1
Appendix IV: AWWA Water Loss Audit ................................................................................................IV-1
Appendix V: 2015 Annual Water Quality Report ...................................................................................V-1
Appendix VI: CUWCC Best Management Practices ............................................................................VI-1
Appendix VII: Draft Water Rationing Ordinance .................................................................................VII-1
2015 Urban Water Management Plan
1-1
Chapter 1: Introduction
The City of San Luis Obispo (City) has diligently monitored and managed its water resources for many
years. This Urban Water Management Plan (Plan) evaluates current and projected water supplies
through the year 2035. The Plan was prepared in accordance with the requirements of the Urban Water
Management Planning Act, as amended and includes the following chapters:
• Water Service Area and System Description
• Water Demand and Reduction Targets
• Water Sources
• Recycled Water
• Water Supply Reliability
• Demand Management Measures
• Water Shortage Contingency Plan
The Plan is consistent with the goals, policies, land uses, and population projections presented in the
City’s General Plan.
1.1 URBAN WATER MANAGEMENT PLANNING ACT
The City’s Plan was prepared in accordance with the Urban Water Management Planning Act (Act). The
Act is defined by the California Water Code (CWC), Division 6, Part 2.6, and Sections 10610 through
10656. The Act requires every urban water supplier that provides water for municipal purposes to more
than 3,000 connections, or supplying more than 3,000 acre-feet (af) of water annually, to adopt and
submit a plan every five years to the California Department of Water Resources (DWR).
Since its passage in 1983, several amendments have been added to the Act, such as those enacted in
2009 related to Senate Bill X7-7 (SB X7-7) requiring each urban retail water supplier to develop urban
water use targets to help meet the 20 percent reduction goal by 2020 and an interim 10 percent goal by
2015. Chapter 4 of this Plan explains the City’s targets and implementation strategy to meet state
requirements related to SBx7-7.
The other recent amendments made to the Act are set forth in SB 1087, Water and Sewer Service Priority
for Housing Affordable to Lower-Income Households. SB 1087 requires water and sewer providers to
grant priority for water service allocations to proposed developments that include low income housing. SB
1087 also requires Urban Water Management Plans to include projected water use for single- and multi-
family housing needed for low-income households. Chapter 4 of this Plan incorporates these reporting
requirements.
The Plan serves as a foundational document and source of information for a Water Supply Assessment,
(Water Code Section 10613), and a Written Verification of Water Supply, (Water Code Section 66473.7).
Both statutes require detailed information regarding water supply availability to be evaluated prior to
approval of specific large development projects.
The purposes of the Plan are to:
• Assess current and future water use trends in the community
• Describe the sources of water supply and the water system
• Assess water supply reliability
• Document the water demand management measures in place to balance supply and demand
• Demonstrate compliance with SB X7-7
• Act as a source document for the City’s General Plan
• Act as a source document on the background and history of the water supply system
• Comply with the state requirements to qualify for water and wastewater State grants and loans.
2015 Urban Water Management Plan
1-2
1.2 AGENCY COORDINATION
The Act requires the City to coordinate the preparation of its Plan with other appropriate agencies,
including other water suppliers that share a common source, water management agencies, and relevant
public agencies. The following is a summary of the coordination that the City took in the preparation of
this Plan. Supporting documentation is provided in Appendix I.
Whale Rock Reservoir Commission
Whale Rock Reservoir provides water to the City, California Polytechnic State University (Cal Poly), the
California Men’s Colony, and the town of Cayucos. The Whale Rock Commission oversees the reservoir
operations and is made up of representatives from the City, California Men’s Colony, and Cal Poly, as
well as a representative from the State Department of Water Resources. The City provides the staff for
oversight of daily operations and maintenance activities. City staff works closely with staff from the
commission members relative to water planning issues. A discussion of the update process for the City’s
Urban Water Management Plan was provided to the commission at its May 2016 meeting.
Cayucos Area Water Organization
The Cayucos Area Water Organization (CAWO) includes the three water purveyors that serve the town of
Cayucos (Paso Robles Beach Water Association, Morro Rock Mutual Water Company, County Service
Area 10A) and the Cayucos-Morro Bay Cemetery District. The Whale Rock Commission and the CAWO
have an agreement which includes a provision to provide up to 600 acre feet of water per year from the
reservoir. The agreement dates back to the period when the dam was being planned and constructed.
The agreement has been amended since that time. The water provided to the CAWO is delivered from
the Whale Rock pipeline to the Cayucos Water Treatment Plant operated by the County of San Luis
Obispo (County). An update regarding the City’s preparation and updating of its UWMP was provided to
the group at its May 2016 meeting.
County Water Resources Advisory Committee
The City is represented on the county-wide Water Resources Advisory Committee (WRAC). The WRAC
is an advisory committee to the County Board of Supervisors on issues pertaining to water resources
planning. The Committee holds monthly meetings to discuss water resource issues, planned projects or
developments, policies, or other related issues that may have county-wide water resource impacts.
Recommendations are forwarded to the County Board of Supervisors for its consideration. The
Committee discusses items ranging from new water supply projects to water conservation programs and
policies. An update regarding the City’s preparation and updating of its UWMP was provided to the
WRAC in April 2016. Review and comment by interested members was requested.
Nacimiento Project Commission
The County has an entitlement of 17,500 acre feet of water from Nacimiento Lake and acts as the
wholesaler of this water supply. The County oversees the project that delivers water from Nacimiento
Reservoir to agencies participating in the Nacimiento Water Project. The current participating entities
include the cities of Paso Robles and San Luis Obispo, Atascadero Mutual Water Company, Templeton
Community Services District, Santa Margarita Ranch, Bella Vista Mobile home park, and County Service
Area 10A (Cayucos).
The Nacimiento Project Commission (Commission) is made up of representatives from each of the four
original participating agencies’ governing boards, as well as a representative from the County Flood
Control and Water Conservation District (i.e. County Board of Supervisors). The Commission provides
oversight and recommendations to the District relative to the project operations and maintenance and the
associated budget. An update regarding the City’s preparation and update of its UWMP was provided to
the Commission’s technical support group at its May 2016 meeting. The County, as the water supply
“wholesaler”, was notified that the City was updating its UWMP in March 2016.
Integrated Regional Water Management Plan
The County has developed an Integrated Regional Water Management Plan which included involvement
and participation by the City as well as other agencies and interested individuals throughout the County.
2015 Urban Water Management Plan
1-3
City staff in particular provided detailed input in the areas of water conservation and water recycling
components of the plan because of the expertise the City has in these areas. The County was notified
that the City was updating its UWMP in March 2016.
1.3 PUBLIC PARTICIPATION AND PLAN ADOPTION
The City encouraged public involvement in the Plan update through a Community Water Forum, Planning
Commission study session, a Planning Commission public hearing for review of the draft document, and
a City Council public hearing for review of the draft document. The City further encouraged involvement of
the public through correspondence, public notices, and offers to meet with interested groups. Public
hearing notifications were published in The Tribune (the local area newspaper). A copy of the published
Notice of Public Hearing, correspondence, and the resolution of adoption are included in Appendix I. The
hearing process provided an opportunity for all City water users to become familiar with the Plan and ask
questions about its water resources in addition to the City’s continuing plans for providing a reliable, safe,
and high-quality water supply.
1.4 PLAN IMPLEMENTATION
Implementation of the Plan is the responsibility of the City’s Utilities Department. Key staff overseeing the
implementation is the Utilities Director, Deputy Director of Utilities and Utilities Services Manager. Annual
updates regarding Plan implementation, as well as other City water resources issues, are provided to the
City Council as part of the City’s annual Water Resources Status Report (Appendix II).
1.5 STANDARDIZED TABLES
In response to the requirements of the CWC, standardized tables for the reporting and submittal of
UWMP data were developed and are required for use in 2015 UWMPs by the State. The standardization
of data tables allows for more efficient data management, expedited review of UWMPs, and easier
compilation of data for regional and statewide planning. The City will submit UWMP data electronically to
DWR using standardized tables and have included the standardized tables in the body of this Plan at the
end of each chapter.
1.6 COMPLIANCE CHECKLIST
The City completed the checklist of specific UWMP requirements and included it in the Plan as Appendix
III as requested by DWR. The Checklist includes each UWMP requirement by subject, applicable CWC
section, and the page number where the required element is addressed in the Plan to assist in the DWR
review of the City’s UWMP.
City of San Luis Obispo Community Water Forum, April 2016.
2015 Urban Water Management Plan
1-4
1.7 ABBREVIATIONS & ACRONYMS
AB - Assembly Bill
AF - Acre-Foot or Acre-Feet
AFY (of afy) - Acre-Feet per Year
AWWA - American Water Works Association
BMP - Best Management Practice
CII - Commercial, Industrial, and Institutional water use sectors
CIMIS - California Irrigation Management Information System
CUWCC - California Urban Water Conservation Council
CWC - California Water Code
DDW - State Water Resources Control Board, Division of Drinking Water
DMMs - Demand Management Measures
DOF - Department of Finance
DWR - California Department of Water Resources
EPA - U.S. Environmental Protection Agency
ETo - Reference Evapotranspiration
GIS - Geographic Information System
GPCD (or gpcd) - Gallons per Capita per Day
GPPD - Gallons per Person per Day
IRWM - Integrated Regional Water Management
LRAA - Locational Running Annual Average
LAFCO - Local Agency Formation Commission
MGD - Million Gallons per Day
NOAA NMFS - National Oceanic and Atmospheric Administration, National Marine Fisheries Service
NPDES - National Pollutant Discharge Elimination System
PCE - Tetrachloroethylene
pH - The measure of how acidic/basic water is ranging from 0 (acidic) to 14 (basic), with 7 being neutral.
PRV - Pressure Reducing Valve
RGPCD - Residential Gallons per Capita Daily
RWQCB - Regional Water Quality Control Board
SB - Senate Bill
SB X7-7 - Senate Bill Seven of the Senate’s Seventh Extraordinary Session of 2009
SDWA - Safe Drinking Water Act
SGMA - Sustainable Groundwater Management Act
SWRCB - State Water Resources Control Board
THMs - Trihalomethanes
UWMP - Urban Water Management Plan
WDR - Waste Discharge Requirement
WRRF - City of San Luis Obispo Water Resources Recovery Facility
WSCP - Water Shortage Contingency Plan
WTP - City of San Luis Obispo Water Treatment Plant
2015 Urban Water Management Plan
1-5
Required UWMP Standardized Tables:
Retail Only: Public Water Systems
Public Water System
Number
Public Water System
Name
Number of Municipal
Connections 2015
Volume of
Water Supplied
2015
4010009 City of San Luis
Obispo 15,116 4,908
TOTAL 15,116 4,908
NOTES: Table 2-1
Volume of water supplied in this table includes potable (4721 AF) and recycled water (187 AF).
Plan Identification (Select One)
Individual UWMP
Regional UWMP (RUWMP)
NOTES: Table 2-2
Agency Identification
Type of Agency (select one or both)
Agency is a wholesaler
Agency is a retailer
Fiscal or Calendar Year (select one)
UWMP Tables Are in Calendar Years
UWMP Tables Are in Fiscal Years
If Using Fiscal Years Provide Month and Day that the Fiscal Year Begins
(dd/mm)
N/A
Units of Measure Used in UWMP (select from Drop
down)
Unit AF
NOTES: Table 2-3
2015 Urban Water Management Plan
1-6
Retail: Water Supplier Information Exchange
The retail supplier has informed the following wholesale supplier(s) of projected
water use in accordance with CWC 10631.
Wholesale Water Supplier Name (Add additional rows as needed)
County of San Luis Obispo
NOTES: Table 2-4
Notification to Cities and Counties
City Name 60 Day Notice Notice of Public
Hearing
None
County Name 60 Day Notice Notice of Public
Hearing
San Luis Obispo
County
NOTES: Table 10-1 (R).
2015 Urban Water Management Plan
2-1
Chapter 2: Service Area and Water System Description
2.1 SERVICE AREA DESCRIPTION
The City of San Luis Obispo is located about half way
between Los Angeles and San Francisco and has a total
area of 10.8 square miles of which 10.6 square miles is
land and 0.18 square miles (1.66 percent) is water.
Situated in a coastal valley approximately 10 miles inland
from the Pacific Ocean, the City’s Mediterranean climate
provides for mild and dry summers and cool winters, with
an annual average of about 23 inches of precipitation.
Summers are generally warm and sunny, often with
morning fog from the Pacific coast. Winters are generally
mild, though below freezing lows may be expected during
the winter. Temperatures vary widely at any time of the
year, with 80° F readings in January and February not
uncommon. Table 1, San Luis Obispo Climate, includes the
average monthly evapotranspiration rate, average
maximum high temperature and average precipitation for
the City of San Luis Obispo. As the City receives water
from reservoirs located in vastly different watersheds,
climate data specific to those surrounding the reservoirs
are utilized in water management models.
The CWC does not require that 2015 Urban Water Management Plans address climate change.
However, the City is concerned about the potential long-term effects of climate change on its water
supply. While the City has secured an adequate water supply to serve the projected buildout of the City,
and uses conservative water projection methods, the City continues to focus on securing supplemental
water sources and promoting conservation to strengthen its multi-source water supply to withstand
potential long-term effects of climate change.
2.2 SERVICE AREA POPULATION PROJECTION & OTHER DEMOGRAPHIC INFORMATION
Founded in 1772 and incorporated in 1856, San
Luis Obispo is one of California’s oldest
communities and now serves as the County’s
hub for commercial and government services.
This section describes the City’s population
projections, demographics information and
employment characteristics.
The City’s population has grown at a slow,
steady pace since 1980. The 2015 population
totaled 45,802. From 1990 to 2015, the City
grew at an average rate of 0.35 percent per
year, with periods of faster or slower growth,
well below the General Plan’s one percent
growth maximum. The majority of the City’s
future growth is projected to be located in the Margarita, Orcutt, and Airport specific plan areas.
Water demand in the City has not increased at a rate that follows the rate of population growth (see
Population and Water Demand charts below). In the past 25 years, annual water demand has been as
high as 6,416 acre-feet in 2007 and as low as 4,040 acre-feet in 1991. This has been influenced by many
factors including annual rainfall totals, plumbing efficiencies such as low flow toilets, shower heads, and
appliances, changes in landscaping and irrigation, economic climate, water rates, and a strong water
conservation ethic.
TABLE 1: San Luis Obispo Climate
Standard
average
ETo (in)
Average
rainfall
(in)
Average
temperature
(F)
January 2.21 5.09 63.1
February 2.50 4.83 64.9
March 3.80 3.63 65.6
April 5.08 1.71 68.4
May 5.70 0.42 70.8
June 6.19 0.07 74.9
July 6.43 0.03 78.3
August 6.09 0.05 79.3
September 4.87 0.33 79.5
October 4.09 0.90 76.7
November 2.89 2.47 70.4
December 2.28 3.84 64.5
Annual 52.13 23.35 71.4
Source: DWR CIMIS Station #53
2015 Urban Water Management Plan
2-2
To be conservative in its water planning, the City uses the one percent population growth rate and 117
gpcd, the maximum per capita water use rate under SB X7-7, described further in Chapter 3. This
approach to projecting future water demand ensures the City’s water needs will be accommodated. The
General Plan Land Use Element, updated in 2014, included population projections from 2020 through
2035 and estimated that the City has an urban reserve capacity of 57,200 residents. Table 3 provides the
City’s population projections.
TABLE 2: City Population
2015 2020 2025 2030 2035 Urban Reserve
Capacity
Population 45,802 48,826 51,317 53,934 56,686 57,200
Source: City of San Luis Obispo, General Plan, Land Use Element, Table 3, 2014.
2015 Urban Water Management Plan
2-3
According to the 2010 Census, the City’s population age demographics are 14.2 percent under the age of
18, 33.6 percent from 18 to 24, 23.7 percent from 25 to 44, 16.5 percent from 45 to 64, and 12.1 percent
who are 65 years of age and older. The median age is 26 years.
The City is the civic, economic and cultural hub of the Central Coast. With these major regional employers
(Table 3), the City has an estimated daytime population of more than 70,000 persons. Public sector jobs
account for a sizeable portion of the job market in the City. Service and retail jobs also comprise a large
percentage of employers. In 2013-14, the median income for a household in the City was $59,628, up
from $40,579 in 2009-10. According to the City's 2014 Comprehensive Annual Financial Report, the top
employers within and adjacent to the City are:
TABLE 3: Top Employers
# Employer # of Employees
1 California Polytechnic State University (Cal Poly) 3,055
2 County of San Luis Obispo 2,465
3 Pacific Gas and Electric 1,900
4 California Men’s Colony 1,540
5 Cal Poly Foundation 1,400
6 San Luis Coastal Unified School District 902
7 Mind Body 650
8 California Department of Transportation 544
9 Cuesta Community College 440
10 Community Action Partnership of San Luis County 410
Source: City of San Luis Obispo 2014 Comprehensive Annual Financial Report.
As the top employer, Cal Poly maintains a student enrollment between 18,260 and 19,780 students with a
projected enrollment at 20,912 students by the year 2020. W hile Cal Poly has its own water supply
source, the City treats and distributes water to the University which is located just outside of City limits.
The City is also a popular tourist destination due to its proximity to beaches and open space areas,
historic downtown, and its overall vitality. The City’s tourism is at its peak during the summer. However,
Cal Poly is also out of session at this time, thus reducing the overall daily population served by the City
during the summer months. In 2015, with the update to its Master Plan underway, Cal Poly indicated that
it is considering the idea of year-round instruction by expanding summer classes.
2.3 WATER SYSTEM DESCRIPTION
The City utilizes surface water reservoirs to meet its current potable water demand. The Salinas
Reservoir, located nine miles southeast of the community of Santa Margarita, has provided water to the
City since 1944. The Whale Rock Reservoir, located one-half mile east of the town of Cayucos, has been
a water source for the City since 1961. Water deliveries from Nacimiento Reservoir, located 14 miles
northwest of the City of Paso Robles, to the City began in January 2011. All surface water supplies are
considered to be of high quality. The City does not currently rely on local groundwater to serve long-term
water supply needs, however it has relied heavily on groundwater during past droughts (such as 1986 to
1990) and could rely on this source in the future during water shortage emergencies.
The City is supplied recycled water from its Water Resource Recovery Facility (WRRF). In 2016, recycled
water is utilized for landscape irrigation and for construction water (dust suppression, compaction, etc.).
The City will be maximizing the production of recycled water with the upgrade of the WRRF scheduled to
begin construction in 2018 and studies are underway to maximize the use of this resource. Recycled
water is discussed further in Chapter 6. Figure 1 shows the location of the City’s reservoirs and
conveyance pipelines.
2015 Urban Water Management Plan
2-4
City of San Luis Obispo Water Treatment Plant.
This section describes the City’s existing potable water system, including transmission, treatment, and
distribution systems. Additional information is provided on the City’s water sources in Chapter 3.
Raw Water Transmission
The raw water transmission facilities deliver water to the City’s Water Treatment Plant from the Salinas,
Whale Rock, and Nacimiento Reservoirs. More detailed information on these raw water transmission
facilities is provided in Chapter 4.
Over the past twenty-five years, surface water treatment and groundwater treatment standards and
regulations have become more stringent. With the enactment of the Safe Drinking Water Act (SDWA) in
1974, Congress authorized the federal government to establish national drinking water regulations. Since
that time, many amendments have been made to the SDWA which require additional monitoring and
treatment which has resulted in increased operational costs. The following sections discuss the impacts
of the current regulations on the City's water treatment facilities and potential impacts of any foreseeable
amendments to the current regulations.
Water Treatment
The City’s Water Treatment Plant (WTP) is located on
Stenner Creek Road, northwest of the Cal Poly campus.
The facility was constructed in 1964 to provide treatment
of surface water from Salinas and Whale Rock
Reservoirs. The WTP is a conventional plant that includes
ozone disinfection, coagulation, flocculation,
sedimentation, and filtration. The WTP was originally
designed to treat up to eight million gallons per day (mgd).
In 1977, the plant was upgraded to provide 11.5 mgd of
treatment capacity but actually treated up to 12 mgd for
limited periods during peak summertime water demands.
In 1994, the WTP was upgraded to comply with new
regulations and to increase the treatment capacity to 16.0
mgd. The WTP was again upgraded with construction completed in March 2008. This upgrade added
additional onsite storage facilities, replaced an existing pump station, and replaced the sedimentation
basin with a new ballasted flocculation process among other improvements. The addition of the Actiflo
process increased the sedimentation process capacity from 8 mgd to 16 mgd. This process was needed
to treat the anticipated water supply from the Nacimiento Reservoir. The Nacimiento Project went online
and began making water deliveries to the WTP in January, 2011.
Since the existing WTP was constructed, the Safe Drinking Water Act (SDWA) was adopted and was
significantly amended. The 1986 amendments were broad in scope and required implementation of new
regulations by the U.S. Environmental Protection Agency (EPA). The SDWA also required the EPA to
specify criteria under which filtration is required as a treatment technique for surface supplies. On June
29, 1989, the EPA issued the Surface Water Treatment Rule which defined the standards for surface
water treatment and had specific compliance deadlines.
The purpose of the regulation is to protect the public, as much as feasible, from waterborne diseases.
Waterborne diseases, most notably Giardia lamblia, Cryptosporidium, and Legionella, are most commonly
transmitted by surface water contamination. For the City, the most significant issue is the regulation
aimed at reducing the formation of disinfection by-products, specifically trihalomethanes (THMs), which
are a group of compounds formed during disinfection by the reaction of chlorine with naturally occurring
organics. While the City had consistently met the previous 100 micrograms per liter limit, there have been
occasional instances in which the standard was exceeded due to the high organic content of Salinas
Reservoir water during certain times of the year. Those new regulations required increased chlorine
contact times which would cause the THM levels to exceed the regulations. The limit for THMs at that
time was a system average of 80 micrograms per liter. The current regulations, Stage 2 of the
Disinfectant By-Product Rule, went into effect in 2013 and changed to a locational running annual
2015 Urban Water Management Plan
2-5
average (LRAA) to determine compliance.
2015 Urban Water Management Plan
2-6
To comply with the standards for THMs, meet anticipated future water quality standards, and increase
water treatment operational efficiency, the City upgraded the WTP in 1994 to use ozone as the primary
disinfectant instead of chlorine. The use of ozone provides enhanced disinfection capability to meet
federal and state requirements while reducing the levels of THMs. The use of ozone also helps produce
water free of objectionable taste and odor associated with algae blooms at Salinas Reservoir and meets
all current, as well as anticipated regulations.
The 1994 upgrade project also increased the capacity of the plant from 11.5 million gallons per day to
16.0 million gallons per day (with the exception of the sedimentation process). This was accomplished
through increased filter efficiency and the ability to treat Whale Rock Reservoir water without using the
sedimentation process (direct filtration). The expanded capacity is sufficient to meet projected water
demand at build-out under the City’s Land Use Element of the General Plan updated most recently in
2014.
Groundwater
With the onset of the drought in 1986, resulting in decreasing surface water supplies, the City activated
groundwater wells in 1989 to meet the City's water demand. In the 2010 update of the Water and
Wastewater Management Element of the General Plan, groundwater was eliminated from the City’s water
supply calculation as a basis for meeting long-term water demands. The decision was based on the water
quality and availability issues which deemed groundwater as a potentially unreliable source. The City will
utilize groundwater in the future, as the resource is needed, and plans to use well-head treatment to
ensure the water quality is appropriate for potable purposes.
Like surface water, groundwater must meet the standards set in the SDWA. Water quality analysis in
1989 indicated that advanced treatment was needed on the now decommissioned Dalidio and Auto Park
Way Wells due to unacceptable levels of tetrachloroethylene (PCE). Carbon adsorption units were placed
on each well to provide necessary treatment, and were granted approval for domestic consumption by the
State of California, Department of Public Health (now the State Water Resources Control Board, Division
of Drinking Water (DDW)).
In November 1992, nitrate levels in the Auto Park Way Well exceeded State standards, so the well was
taken out of service. In April 2015, the City stopped utilizing the Pacific Beach Well on Los Osos Valley
Road for potable water purposes due to more stringent regulations for hexavalent chromium. The Fire
Station #4 Well had been offline due to remediation of soil contamination at the adjacent Shell service
station and is also currently offline due to hexavalent chromium.
The 1996 Amendments to the SDWA required the EPA to develop regulations that require disinfection of
ground water systems to protect the public health. In 2006, the Groundwater Rule was adopted to further
protect against waterborne illness due to fecal and E. Coli contamination in public water systems that use
groundwater supplies.
Possible Future Regulatory Changes
As analytical techniques allow for lower levels of regulated water contaminants to be detected and new
contaminants are added to the regulatory list issued by the EPA and state regulatory agencies, there may
be impacts on the City's water treatment operations. While the WTP upgrade was designed to meet then
current and anticipated future water treatment standards, additional future or new regulations may require
additional modifications, depending on the action levels adopted by the federal and state regulatory
agencies. The following are possible regulatory changes which may influence WTP operations:
Regulation of total organic carbon. Could require optimizing enhanced coagulation
processes, which may add a pH reduction system to the treatment process (i.e. acid feed,
carbon dioxide feed, etc.).
Regulation of THM sub-species. Chlorinated bromides would most likely be targeted,
which would not necessarily be problematic unless the action level is extremely low.
2015 Urban Water Management Plan
2-7
2015 Urban Water Management Plan
2-8
2016 Water Main Replacement Project.
Regulation of hypochlorites. Chlorates caused by the decomposition of hypochlorite
solution may require coolers or insulation be installed on holding tanks to stabilize
temperature inside the tanks. This is a requirement now being considered by the State.
Regulation of THMs via LRAA. THMs are now regulated on a LRAA instead of a system -
wide average. This could require changing from hypochlorite to chloramines for final
disinfection and/or adding aeration systems to storage tanks and reservoirs.
The effect of any of the potential regulations on the City's treatment operations is dependent on the action
level adopted. More technical and complicated processes may require training or hiring of personnel
skilled in the maintenance of sophisticated electronic equipment and with increased knowledge in
telemetry and computer programming.
Potable Water Distribution System
The City’s potable water distribution system
delivers water from the WTP to approximately
15,000 metered customers and over 2,000 fire
hydrants via two storage reservoirs, five hydro-
pneumatic tanks, eight pump stations, ten
water tanks, and approximately 185 miles of
water mains.
The water delivered from the WTP is split into
two main distribution networks. The WTP has
a major pump station (the Transfer Pump
Station) that pumps water to the high pressure
zones which provides service to the higher
elevation areas in the City. The transfer pumps
take approximately half of the water, increase
the pressure, and then provide water to
Stenner Canyon Reservoir (Reservoir #2), Cal
Poly, and other portions of the City, generally north and east of the Union Pacific Railroad tracks. Water
flows by gravity directly into the lower pressure zone from the WTP's onsite clear well tanks.
Water storage facilities are necessary to provide water during peak demand periods and emergency
situations such as fires. The City has twelve water storage facilities, nine of which are steel storage tanks
ranging in size from 0.04 to four million gallons and three concrete facilities with a capacity of 0.35 to 7.5
million gallons. The combined storage capacity is 26.22 million gallons. The holding capacity of the
various facilities and tank locations throughout the City are shown in Figure 3.
The goal is to provide uninterrupted water flow at adequate pressures (between 40 pounds per square
inch (psi) and 80 psi) to meet all fire and domestic flow requirements and to minimize system water loss
due to leakage. This pressure range will meet the needs of most irrigation sprinklers and other uses, and
provide adequate pressure for fire sprinkler systems. In order to accomplish this, the City’s Water
Distribution staff has eight major work objectives. They are as follows:
1. Pump station and tank maintenance
2. Water main maintenance and repair
3. Valve exercise and repair
4. Water service repair and renewal
5. Fire hydrant maintenance and replacement
6. Cross connection control
7. Underground Service Alert (USA) markouts
8. Bacteriological sampling
2015 Urban Water Management Plan
2-9
2015 Urban Water Management Plan
2-10
Water Storage Tank.
Because of the geographic setting of the City, pressure zones are established in the distribution system to
maintain these pressure ranges (see Figure 2). The City’s water distribution system is a complex system
of 16 pressure zones and 18 pressure regulating valves. It is unlikely this distribution pattern will change,
since the WTP will continue to be the principal source of treated water for the City.
Aging pipes must be replaced to avoid major service disruptions and leaks due to deterioration. Parts of
the City's water system are approaching or past their estimated lifespan with most of the pipes being
made of cast and ductile iron. Other pipes are made of asbestos cement, or, since the mid-1970's,
polyvinyl chloride (PVC). Water pipes serve two basic functions:
1. Larger pipes or transmission mains (ranging in size from 12 to 30 inches), move large volumes of
water from one portion of the City to another
2. Smaller pipes or distribution mains (ranging in size from four inches in the older portions of the
City to 12 inches) distribute water within a local area and deliver it to each property in the City
Fire protection is an important service the City provides to its residents. The fire protection system is a
network of over 2,000 public hydrants and approximately 200 private hydrants.
The engineering estimate for the life expectancy of these facilities is 50 years or more depending on pipe
type. Complete replacement within the term of life expectancy would require that the City replace an
average of two percent of the system infrastructure each year which is the City’s adopted goal. Pipelines
are prioritized for replacement in the City’s 2016 Potable Water Distribution System Operations Master
Plan.
Operation and Maintenance
In order to retain a reliable water distribution system, preventative maintenance is performed by the City’s
Water Distribution operators. Preventative maintenance is necessary to minimize water service disruption
and prolong system service life.
The City’s comprehensive mainline valve exercise program is beneficial to ensure proper operation of
valves and minimizes disruptions to water customers during an emergency shutdown. The program
assists in identifying problem areas such as broken valves, broken operating nuts, buried gatewells, and
misaligned access sleeves. Identified problem areas are
scheduled for repair or replacement which minimizes future
distribution problems and ensures availability in the event of
fire. In addition, a valve exercise program assures that fire
hydrants can be isolated for maintenance and repair. The
program has a goal of exercising 1,000 of the system’s
estimated 5,000 valves per year, allowing for all valves in the
system to be exercised every five years.
Since electrical and mechanical pumping equipment consists of
moving parts that are subject to wear, a comprehensive
preventative maintenance program is required to prolong the
useful life and avoid costly emergency equipment breakdowns
Weekly inspections of the City’s pump station are performed.
Preventive and corrective maintenance is performed as needed.
The City’s water storage tanks are an important component of
the water distribution system. As a result of the storage
facilities, the system's flow and pressures are improved and
stabilized to better serve the customers within a storage tank’s
zone. Additionally, these supplies serve as a reserve for
emergencies such as fire suppression and power outages.
Regular inspections and preventative maintenance are
necessary to protect the City's investment in these facilities. This includes regularly-scheduled inspections
and cleaning of probes and relays, paint and protective coatings, facility security systems, maintenance of
access roads and sites, and monitoring of cathodic protection systems.
2015 Urban Water Management Plan
2-11
The service line (from the water main to the customer water meter) repair and replacement program has
been a major priority for the City due to the high likelihood of failure of previously installed polybutylene
pipe and ongoing concerns with the longevity and durability of galvanized pipe. The City's water service
lines currently consist of mainly copper and polyethylene pipe, but small amounts of polybutylene and
galvanized pipe still exist in the system. The City actively removes and replaces polybutylene and
galvanized materials as they are discovered through routine maintenance and CIP projects. The majority
of the City’s water lines have been upgraded to copper and polyethylene material due to the longevity and
durability of these two types of materials.
Pressure reducing valves (PRVs) are necessary to maintain acceptable pressure levels in both low lying
and higher elevation areas of the City. These valves reduce plumbing failures and system leakage in
areas that would otherwise experience high pressure. The City has 18 PRVs that are inspected and
tested annually, and rebuilt periodically as part of a PRV maintenance program.
To ensure that fire hydrants operate correctly when needed, testing, maintenance, and repair is
performed on an annual basis. It is the responsibility of the Water Distribution staff to perform all
maintenance, repairs, and hydrant replacement as needed. Hydrant exercising and flushing is performed
by the City in order to proactively identify hydrants that require maintenance.
Prior to placing a newly constructed water line into service, procedures are in place for disinfection,
sampling, and testing consistent with guidelines provided by American Water Works Association. The
City’s Water Distribution and Water Quality Laboratory staff provide the bacteriological sampling and
testing. These procedures assure that all new water lines are free of waterborne pathogens before they
are placed in service, protecting the health and safety of water users.
All City-related Underground Service Alerts (USA) mark outs (potable water, wastewater, recycled water,
storm drains, fiber optics, and street lights) are consolidated under a single position in the Water
Distribution section of the Utilities Department. Consolidation streamlined the process and increased
staffing efficiencies. The management of the Underground Utility Locator is the responsibility of the Water
Distribution Supervisor.
The City’s distribution system is a “D4” system based on rating criteria that classifies the complexity of the
system. The State has mandated certification for water distribution operators (minimum of a Grade D1).
The City requires water distribution operators to attain Grade D3 certification. Continuing education is
mandatory for periodic certification renewals.
Contract Meter Reading
With the desire to consolidate the meter reading routes into a five-day period at the beginning of each month
for consistent billing purposes, the City started utilizing a contractor to read the approximately 15,000 meters
in early 2015.
2015 Urban Water Management Plan
2-12
2.4 Required UWMP Standardized Tables:
Population - Current and Projected
Population
Served
2015 2020 2025 2030 2035 2040(opt)
45,802 48,826 51,317 53,934 56,686 N/A
NOTES: Table 3-1 R (Retail).
SOURCE: City of San Luis Obispo, General Plan, Land Use Element, Table 3, 2014.
2015 Urban Water Management Plan
3-1
Chapter 3: Current and Projected Water Demand
This chapter includes information on historical potable water demand in the City, current use, and
projections of future potable water demand. Projections are based on information in the City’s General
Plan Land Use Elem ent updated in 2014.
3.1 WATER USE BY SECTOR
Existing water use in the City includes single-family and multi-family residential water users, commercial,
institutional and industrial water users (collectively “CII”), and dedicated irrigation services. Water system
loss and unbilled authorized consumption are also recorded by the City and are covered in detail in
section 3.3. At this time the City does not provide potable or Title 22 recycled water for use for agricultural
purposes, groundwater recharge, conjunctive use, saline water intrusion barriers, wetland or wildlife
habitat, or sales/transfers/exchanges to other agencies.
The projected deliveries were developed using the City’s General Plan Land Use Element, updated in
2014, population estimates and 117 gpcd as shown in Table 4. Please note that this number does not
include recycled water use.
TABLE 4: Current and Projected Water Use by Sector 1
Water Use Sectors
Single
Family
Multi-
family
Commercial,
Industrial,
and Institutional
Dedicated
Irrigation
System Water
Loss
Unbilled
Authorized
Consumption
Volume
2015 Water Use
AFY 1,837 1,019 1,142 299 363 62 4,722
2020 Water Use
AFY 2,489 1,381 1,548 404 493 84 6,399
2025 Water Use
AFY 2,616 1,451 1,627 425 518 88 6,725
2030 Water Use
AFY 2,750 1,525 1,710 447 544 93 7,069
2035 Water Use
AFY 2,890 1,603 1,797 470 572 97 7,429
NOTES:
1. Department of Water Resources, Tables 4-1 & 4-2.
2. Projected water demand for 2020 to 2035 is based on 117 gpcd.
3. Population growth is projected at one percent per year, per the City's Land Use Element, Table 3, 2014.
4. Projections do not include increases in recycled water demand. Additional information on future recycled water demand is
provided in Chapter 6.
Source: City of San Luis Obispo Utilities Department, 2016.
3.2 DEMAND SECTOR DEFINITIONS
Potable water demand in the City is comprised of several sectors, consisting of the following:
• Single-family Residential: A single-family dwelling unit. A lot with a free-standing building
containing one dwelling unit that may include a detached secondary dwelling unit.
• Multi-family Residential: Multiple dwelling units contained within one building or several
buildings within one complex.
• Landscape: Water connections supplying water solely for landscape irrigation. Such landscapes
may be associated with multi-family, commercial, industrial, or institutional/government sites, but
are considered a separate water use sector if the connection is solely for landscape irrigation.
• Commercial: A water user that provides or distributes a product or service. CWC 10608.12 (d).
2015 Urban Water Management Plan
3-2
• Industrial: A water user that is primarily a manufacturer or processor of materials as defined by
the North American Industry Classifications System (NAICS) code sectors 31 to 33, inclusive, or
an entity that is a water user primarily engaged in research and development. CWC 10608.12 (h).
• Institutional: A water user dedicated to public service. This type of user includes, among other
users, higher education institutions, schools, courts, churches, hospitals, government facilities,
and nonprofit research institutions. CWC 10608.12(i).
• Distribution System Losses: Reporting of system losses is required by the CWC in 2015
UWMPs. Examples of system losses can be seen in Table 5.
• Unbilled, Authorized Consumption: water used for firefighting, line flushing, and other
authorized but unbilled uses.
The City compiles commercial, industrial, and institutional accounts in one category known as “CII.”
3.3 WATER LOSS AND UNBILLED AUTHORIZED CONSUMPTION TYPES
Water losses can be the result of a variety of issues such as water line leaks, meter inaccuracies, and
data handling errors. This is not to be confused with unbilled authorized consumption which accounts for
firefighting, mainline flushing, fire flow testing, and other authorized uses of water that are not billed by the
City. In 2009, the City began utilizing the American Water Works Association’s (AWWA) Water Audit and
Water Balance software to develop a methodology for tracking and reducing non-revenue water and
water loss. Water loss for 2015 and projected future water loss can be seen in Table 4. A sample of
common water loss and unbilled authorized consumption types can be seen in Table 5.
TABLE 5: Common Water Loss and Unbilled Authorized Consumption Types
3.4 ESTIMATING FUTURE WATER SAVINGS
As water savings from codes, standards, ordinances, and transportation and land use plans drive
reduction in water demand within the City, CWC 10631 (e) (4) (B) (ii) requires that it is noted in the Urban
Water Management Plan that 2020, 2025, 2030, and 2035 water use forecasts do not reflect any
representation of water savings from codes, standards, ordinances, or transportation and land use plans.
3.5 LOW INCOME HOUSING
The water use projections provided in Table 4 include the projected water use for all future single-family
and multi-family housing needed for lower income households, as defined in Section 50079.5 of the
Health and Safety Code and the City’s 2015 Housing Element, as required by CWC 10631.1.
Table 6 shows quantity and category of lower income housing units as identified in the Housing Element
and estimated water use for each housing type.
Examples of Water Loss & Unbilled Authorized Consumption Causes
Water Loss Mainline & Service Line
Leakage
Meter
Inaccuracies
Data Handling
Errors
Overflow of
Storage Tanks
Unbilled
Authorized
Consumption
Fire Fighting Mainline Flushing Fire Flow Testing Water Quality
Testing
2015 Urban Water Management Plan
3-3
TABLE 7: Target Method 3
Hydrologic Region Goals
Hydrologic Region
"2020 Plan"
Regional
Targets
Method 3
Regional
Targets
(95%)
North Coast 137 130
North Lahontan 173 164
Sacramento River 176 167
San Francisco Bay 131 124
San Joaquin River 174 165
Central Coast 123 117
Tulare Lake 188 179
South Lahontan 170 162
South Coast 149 142
Colorado River 211 200
Hydrologic Region
"2020 Plan"
Regional
Targets
Method 3
Regional
Targets
(95%)
North Coast 137 130
North Lahontan 173 164
Sacramento River 176 167
San Francisco Bay 131 124
San Joaquin River 174 165
Central Coast 123 117
Tulare Lake 188 179
South Lahontan 170 162
South Coast 149 142
Colorado River 211 200
Source: Department of Water Resources.
TABLE 6: Water Demand for Lower Income Housing Units
Notes:
Estimated water use was calculated using the following conservative water demand rates:
Single-Family Units: 0.3 AFY/Unit
Multi-Family Units: 0.18 AFY/Unit
Source: City of San Luis Obispo, Housing Element, Table 3, Regional Housing Needs Allocation, City of San Luis
Obispo, 2014-2019.
3.6 BASELINES AND TARGETS FOR WATER USE REDUCTION BY 2020
The Water Conservation Act of 2009 (SB X7-7) was
incorporated into Division 6 of the CWC in 2009.
According to the CWC, urban retail water suppliers
must include in their urban water management plan the
baseline daily per capita water use, along with the
basis for determining the estimate, including references
to the supporting data. The legislation specifically calls
for using the methodologies and criteria developed by
the DWR and contained in the guidance document
Methodologies for Calculating Baseline and
Compliance Urban Per Capita Water Use to determine
compliance as required in the years 2015 and 2020.
The legislation directs urban water suppliers to adopt
one of the four outlined options or Target Methods in
the legislation to determine their urban water use
targets.
As the City has invested in and implemented water
conservation programs since 1988, the baseline
periods outlined in the SB X7-7 used to create water
use targets in 2015 and 2020 are not achievable using
Target Method 1, a flat 20 percent reduction from the
baseline period. After reviewing and analyzing the
considerable resources required to perform Target
Methods 2 and 4, the City chose Target Method 3.
This method uses the state hydrologic region target as
set forth in SB X7-7. This method represents the local
climate and geography, it is important to note that the City lies completely within Central Coast Region
(Region 3). The Central Coast Region’s 2020 target, expressed in gpcd, is the lowest in the state. Central
Coast region goals can be compared with other regions in Table 7.
3.7 Updating Calculations from 2010 UWMP
In accordance with CWC 10608.20 (g), and per the recommendation of DWR, the City examined its 2020
Urban Water Use Target and will continue to utilize Method 3 (Hydrologic Region Goals); the City will not
change its Target Method.
Income Category Single-Family
Units
Multi-family
Units
Total
Units
Estimated Water Use
(in acre feet)
Extremely Low 0 142 142 25.56
Very Low 0 143 143 25.74
Low 72 107 179 40.86
Total 72 392 464 92.16
2015 Urban Water Management Plan
3-4
Per DWR’s required use of 2010 U.S. Census data, and to correct for discrepancies between DOF’s
projected populations for 2010, and actual census population data for 2010, the City updated the baseline
population calculations for the 2015 Urban Water Management Plan. The population corrections have
made slight changes to the 10-year average baseline GPCD, and the five-year average baseline gpcd,
but have not changed the City’s 2015 Interim, or 2020 Urban Water Use Reduction Goals as defined in
Method 3. The 2015 Interim Goal and 2020 Goal still stand at 120 gpcd and 117 gpcd respectively as
noted in Table 12.
A new requirement in the 2015 UWMP is completion and submission of the SB X7-7 Standardized
Tables. These tables compile in-depth information about SB X7-7 and provide proof of compliance with
the Water Conservation Act of 2009. A completed list of these standardized tables is provided at the end
of this chapter.
3.8 Baseline Periods
In 2010 UWMP the City defined both ten-year (Baseline gpcd) and five-year (Target Confirmation)
baseline periods; these periods remain unchanged from the 2010 UWMP and are used to establish the
2015 interim, and 2020 Target Goals, along with baseline period per capita figures for water use
reduction. Table 8 defines the 10-year baseline period from 1997-2006 and the five-year baseline period
from 2004-2008. The methodology used to establish ten-year and five-year baseline periods is included
below.
As defined by CWC 10608.12 (b), “base daily per capita water use” is defined as:
(1) The urban retail water supplier’s estimate of its average gross water use, reported in
gallons per capita per day and calculated over a continuous 10-year period ending no
earlier than December, 31 2004, and no later than December 31, 2010.
Or
(2) For an urban water supplier that meets at least 10 percent of its 2008 measured retail
water demand through recycled water that is delivered within the service area of urban
water supplier or its urban wholesale water supplier, the urban water supplier may extend
the calculation described in paragraph (1) up to an additional five years to a maximum
continuous period ending no earlier than December 31, 2004, and no later than
December 31, 2010.
Through analysis of the quantity of total water deliveries made up of recycled water in 2008, it was
discovered that the City did not meet the ten percent threshold required to use a 15-year baseline period,
leading the City to follow CWC 10608.12 (b) (1) guidance to use a ten-year baseline period. The City’s
ten-year baseline period of 1997 to 2006 and corresponding populations, annual gross water use, and
daily per capita water use (gpcd) calculations provided by DWR can be viewed in SB X7-7 Table 1.
In accordance with CWC 10608.12 (b) the City calculated its five-year baseline average period water use.
Ranging from 2004-2008, the five-year time frame was selected in accordance with Methodology 3: Base
Daily Per Capita Water Use.
2015 Urban Water Management Plan
3-5
TABLE 8: Baseline Period Ranges
1 If the 2008 recycled water percent is less than ten percent, the first baseline period is a continuous ten-year period. If the
amount of recycled water delivered in 2008 is ten percent or greater, the first baseline period is a continuous ten- to 15-year
period.
2 The ending year must be between December 31, 2004 and December 31, 2010.
3 The ending year must be between December 31, 2007 and December 31, 2010.
NOTE: SB X7-7 Table 1.
3.9 Service Area Population
For the 2015 UWMP, the City’s service area boundaries have been found to correspond by 95 percent or
more with the city limits. This correspondence allows the City to use Department of Finance population
estimates as defined in DWR’s Urban Water Management Guidebook. These population estimates have
been updated from the 2010 UWMP to reflect differences in population between the Department of
Finance projections and the 2010 Census. Population data for each of the baseline years can be found in
Table 10.
3.10 Gross Water Use
As defined by CWC 10608.12 (g), “Gross Water Use” means the total volume of water, whether treated or
untreated, entering the distribution system of an urban water supplier, excluding all of the following:
(1) Recycled water that is delivered within the service area of an urban water supplier or its urban
water wholesale water supplier
(2) The net volume of water the urban retail water supplier places into long term storage
(3) The volume of water the urban retail water supplier conveys for use by another urban water
supplier
(4) The volume of water delivered for agricultural use, except as otherwise provided in subdivision (f)
of Section 10608.24.
The City’s gross water use is exclusively comprised of water entering the distribution system from four
sources: Salinas Reservoir, Whale Rock Reservoir, Nacimiento Reservoir, and groundwater. Per
Methodology 1: Gross Water of the methodologies document, recycled water delivered within the service
area is excluded from the calculation of gross water. Water suppliers are not required to report their
recycled water use, nor demonstrate any reduction in recycled water use for the purposes of SB X7-7.
For detailed information on volume of water that entered the distribution during the baseline periods and
in 2015, please refer to Table 9.
Baseline Parameter Value Units
10- to 15-year
baseline period
2008 total water deliveries 6,359 Acre
Feet
2008 total volume of delivered recycled water 90 Acre
Feet
2008 recycled water as a percent of total deliveries 1.41 Percent
Number of years in baseline period 1 10 Years
Year beginning baseline period range 1997
Year ending baseline period range 2 2006
5-year
baseline period
Number of years in baseline period 5 Years
Year beginning baseline period range 2004
Year ending baseline period range 3 2008
2015 Urban Water Management Plan
3-6
TABLE 9: Annual Gross Water Use
Baseline Year
Volume
Into
Distribution
System
Deductions
Annual
Gross
Water
Use
Exported
Water
Change
in Dist.
System
Storage
(+/-)
Indirect
Recycled
Water
Water
Delivered
for
Agricultural
Use
Process
Water
10 to 15 Year Baseline - Gross Water Use
Year 1 1997 6219.76 0 0 0 0 0 6,220
Year 2 1998 5852.94 0 0 0 0 0 5,853
Year 3 1999 6172.13 0 0 0 0 0 6,172
Year 4 2000 6121.19 0 0 0 0 0 6,121
Year 5 2001 5885.52 0 0 0 0 0 5,886
Year 6 2002 6031.44 0 0 0 0 0 6,031
Year 7 2003 5968.75 0 0 0 0 0 5,969
Year 8 2004 6238.95 0 0 0 0 0 6,239
Year 9 2005 6098.43 0 0 0 0 0 6,098
Year 10 2006 5990.47 0 0 0 0 0 5,990
10 - 15 year baseline average gross water use: 6,058
5 Year Baseline - Gross Water Use
Year 1 2004 6,239 0 0 0 0 0 6,239
Year 2 2005 6,098 0 0 0 0 0 6,098
Year 3 2006 5,990 0 0 0 0 0 5,990
Year 4 2007 6,416 0 0 0 0 0 6,416
Year 5 2008 6,269 0 0 0 0 0 6,269
5 year baseline average gross water use: 6,203
2015 Compliance Year - Gross Water Use
2015 4,721 0 0 0 0 0 4,721
NOTE: Volume into distribution: Salinas Reservoir, Whale Rock Reservoir, Nacimiento Reservoir, and
groundwater.
3.11 Baseline Per Capita Water Use
Daily Per Capita Water Use was calculated for the ten-year, five-year, and 2015 compliance year periods
(see Table 10). The ten-year average baseline per capita water use was calculated at 123 gpcd while the
five-year average baseline per capita water use totaled 124 gpcd. The 2015 compliance year figure of 92
gpcd is extremely low due to the prolonged drought and corresponding conservation efforts. The City
believes this number was driven to such a low level in part due to the Governor’s 2015 emergency
drought declaration.
2015 Urban Water Management Plan
3-7
TABLE 10: Daily Per Capita Water Use
Baseline Year
Service
Area
Population
Annual
Gross
Water
Use
Daily
Per
Capita
Water
Use
(GPCD)
10 to 15 Year Baseline GPCD
Year 1 1997 42,983 6,220 129
Year 2 1998 43,421 5,853 120
Year 3 1999 43,766 6,172 126
Year 4 2000 44,179 6,121 124
Year 5 2001 44,293 5,886 119
Year 6 2002 44,406 6,031 121
Year 7 2003 44,293 5,969 120
Year 8 2004 44,271 6,239 126
Year 9 2005 44,630 6,098 122
Year 10 2006 44,483 5,990 120
10-15 Year Average Baseline GPCD 123
5 Year Baseline GPCD
Baseline Year
Service
Area
Population
Gross
Water
Use
Daily
Per
Capita
Water
Use
Year 1 2004 44,271 6,239 126
Year 2 2005 44,630 6,098 122
Year 3 2006 44,483 5,990 120
Year 4 2007 44,438 6,416 129
Year 5 2008 44,650 6,269 125
5 Year Average Baseline GPCD 124
2015 Compliance Year GPCD
2015 45,802 4,722 92
3.12 2015 and 2020 Targets
Per CWC 10608.20 (e), water retailers must
include both an urban water use target, and an
interim urban water use target in their Urban
Water Management Plan. These targets are
often referred to as the 2015 interim target and
the 2020 target.
As detailed in section 3.6, the City will be using
Target Method 3 to comply with SB X7-7. As
noted in Table 7, the Central Coast Hydrologic
Region must reduce the regional goal of 123
gpcd by five percent, effectively establishing a
117 gpcd goal for the City.
As a requirement of CWC 10608.22, an urban
water supplier’s per capita daily water use
reduction shall be no less than five percent base
per capita water use as defined in the five-year
baseline average. This calculation, and
compliance is confirmed Table 11. The Central
Coast Region target goal of 117 gpcd requires a
six percent reduction in per capita water use,
thus satisfying the requirement for at least a five
percent reduction.
The 2015 interim urban water use target is
established by calculating the value halfway
between the ten-year baseline gpcd (123 gpcd)
and the confirmed target of 117 gpcd listed in
Table 12. This value of 120 gpcd is the City’s
2015 interim target.
All information and DWR tables used to develop
baselines and the resulting targets for 2015 and
2020 can be viewed at the end of this chapter.
The summarized information in Table 14 is
provided at the recommendation of DWR for
quick verification of compliance with the Water
Conservation Act of 2009.
2015 Urban Water Management Plan
3-8
TABLE 12: 2015 Interim Target
Confirmed
2020 Target
10-15 year
Baseline GPCD
2015 Interim
Target GPCD
117 123 120
TABLE 11: Confirmed 2020 Targets
5 Year
Baseline
GPCD
Maximum
2020
Target*
Calculated
2020 Target
Confirmed
2020
Target
124 118 117 117
* Maximum 2020 Target is 95% of the 5 Year Baseline GPCD
Notes: 117 GPCD is from Target Method 3
TABLE 13: Baselines and Targets Summary
3.13 Compliance Daily Per Capita Water Use (GPCD)
In 2015, the SB X7-7 interim reduction target of 120 GPCD was met and surpassed by the City. 2015
potable water usage and gpcd figures were significantly reduced due to conservation efforts, prolonged
drought, and Governor Brown’s April, 2015 drought declaration, requiring a statewide 25 percent
reduction in potable water use.
Baseline
Period Start Year End Year Average Baseline
GPCD*
2015 Interim
Target *
Confirmed 2020
Target*
10 year 1997 2006 123 120 117
5 Year 2004 2008 124
*All values are in Gallons per Capita per Day (GPCD)
2015 Urban Water Management Plan
3-9
TABLE 15: Average GPCD
Timeframe GPCD
10-Year Average (2006-2015) 112
5-Year Average (2011-2015) 104
Pre-drought Average (2006-2011) 117
TABLE 14: 2015 SB X7-7 Compliance
In accordance with statewide reduction efforts and Executive Order B-29-15, the City was required to
reduce residential gallons per capita daily (RGPCD) consumption by 12 percent from 2013 usage levels.
Due to a long history of successful conservation strategies, along with strong community support, the City
surpassed both its drought reduction goals and its SB X7-7 interim water use reduction goal of 120 gpcd.
Actual 2015 per capita water demand is
provided in Figure 4, along with per
capita water demand from 2005 (122
gpcd) to 2015 (92 gpcd). Due to the
increased conservation efforts and
Governor Brown’s statewide emergency
drought declaration, City staff believes
Based on historic use, 2010 to 2014
water demand may be a more accurate
representation of the City’s future post-
drought water demand than demand
during 2015. Table 15 provides five-year,
ten-year, and pre-drought daily per capita averages.
Figure 4: 2005 to 2015 Annual per Capita Water Demand (in Gallons)
Actual
2015
GPCD
2015
Interim
Target
GPCD
Optional Adjustments to 2015 GPCD
2015
GPCD
Did
Supplier
Achieve
Targeted
Reduction
for 2015?
Extraordinary
Events
Economic
Adjustment
Weather
Normalization
TOTAL
Adjustments
Adjusted
2015
GPCD
92 120 0 0 0 0 92 92 Yes
*All values are in Gallons per Capita per Day (GPCD)
2015 Urban Water Management Plan
3-10
3.14 Required UWMP Standardized Tables:
Demands for Potable and Raw Water - Actual
Use Type
2015 Actual
Additional Description
Level of
Treatment When
Delivered
Volume
Single Family Drinking Water 1,837
Multi-Family Drinking Water 1,019
Landscape Does not include recycled water Drinking Water 299
Other CII Drinking Water 1,142
Losses Drinking Water 363
Other Unbilled Authorized Drinking Water 62
TOTAL 4,722
NOTES: Other "CII" contains commercial, industrial, and institutional account types
UWMP Table 4-1 R (Retail).
Demands for Potable and Raw Water - Projected
Use Type Additional
Description
Projected Water Use
2020 2025 2030 2035
Single Family 2,376 2,498 2,625 2,759
Multi-Family 1,318 1,386 1,456 1,531
Landscape Does not include RW 386 406 426 448
Other CII 1,478 1,553 1,632 1,716
Losses 470 494 520 546
Other Unbilled Authorized 80 84 88 93
TOTAL 6,108 6,421 6,747 7,093
NOTES: UWMP Table 4-2 R (Retail).
2015 Urban Water Management Plan
3-11
Total Water Demands
2015 2020 2025 2030 2035
Potable and Raw Water
From Tables 4-1 and 4-2 4,722 6,108 6,421 6,747 7,093
Recycled Water Demand
From Table 6-4 0 0 0 0 0
TOTAL WATER DEMAND 4,722 6,108 6,421 6,747 7,093
NOTES: UWMP Table 4-3 R (Retail).
Recycled water is not included here as the City’s recycled water deliveries did not total 10 percent as
required for reporting purposes to clearly distinguish recycled water and potable water demand.
12 Month Water Loss Audit Reporting
Reporting Period Start Date
(mm/yyyy) Volume of Water Loss
01/2015 363.432
NOTES: UWMP Table 4-4 R (Retail).
Inclusion in Water Use Projections
Are Future Water Savings Included in Projections?
No
Are Lower Income Residential Demands Included In Projections? Yes
NOTES: UWMP Table 4-5 R (Retail).
2015 Urban Water Management Plan
3-12
3.15 SENATE BILL X7-7 Standardized Tables:
SB X7-7 Table 0: Units of Measure Used in UWMP*
Acre Feet
*The unit of measure must be consistent with Table 2-3
SB X7-7 Table-1: Baseline Period Ranges
Baseline Parameter Value Units
10- to 15-year
baseline
period
2008 total water deliveries 6,359 Acre Feet
2008 total volume of delivered recycled water 90 Acre Feet
2008 recycled water as a percent of total deliveries 1.42% Percent
Number of years in baseline period1, 2 10 Years
Year beginning baseline period range 1997
Year ending baseline period range3 2006
5-year
baseline
period
Number of years in baseline period 5 Years
Year beginning baseline period range 2004
Year ending baseline period range4 2008
1If the 2008 recycled water percent is less than 10 percent, then the first baseline period is a continuous 10-year period. If the
amount of recycled water delivered in 2008 is 10 percent or greater, the first baseline period is a continuous 10- to 15-year
period. 2 The Water Code requires that the baseline period is between 10 and 15 years. However, DWR
recognizes that some water suppliers may not have the minimum 10 years of baseline data.
3The ending year must be between December 31, 2004 and December 31, 2010.
4The ending year must be between December 31, 2007 and December 31, 2010.
2015 Urban Water Management Plan
3-13
SB X7-7 Table 2: Method for Population Estimates
Method Used to Determine Population
1. Department of Finance (DOF)
DOF Table E-8 (1990 - 2000) and (2000-2010) and
DOF Table E-5 (2011 - 2015) when available
2. Persons-per-Connection Method
3. DWR Population Tool
4. Other
DWR recommends pre-review
SB X7-7 Table 3: Service Area Population
Year Population
10 to 15 Year Baseline Population
Year 1 1997 42,983
Year 2 1998 43,421
Year 3 1999 43,766
Year 4 2000 44,179
Year 5 2001 44,293
Year 6 2002 44,406
Year 7 2003 44,293
Year 8 2004 44,271
Year 9 2005 44,630
Year 10 2006 44,483
5 Year Baseline Population
Year 1 2004 44,271
Year 2 2005 44,630
Year 3 2006 44,483
Year 4 2007 44,438
Year 5 2008 44,650
2015 Compliance Year Population
2015 45,802
2015 Urban Water Management Plan
3-14
SB X7-7 Table 4: Annual Gross Water Use *
Baseline Year
Fm SB X7-7 Table 3
Volume Into
Distribution
System
This column
will remain
blank until SB
X7-7 Table 4-A
is completed.
Deductions
Annual
Gross
Water
Use
Exported
Water
Change in
Dist. System
Storage
(+/-)
Indirect
Recycled
Water
This column
will remain
blank until SB
X7-7 Table 4-
B is
completed.
Water
Delivered for
Agricultural
Use
Process Water
This column
will remain
blank until SB
X7-7 Table 4-D
is completed.
10 to 15 Year Baseline - Gross Water Use
Year 1 1997 6,220 - -
6,220
Year 2 1998 5,853 - -
5,853
Year 3 1999 6,172 - -
6,172
Year 4 2000 6,121 - -
6,121
Year 5 2001 5,886 - -
5,886
Year 6 2002 6,031 - -
6,031
Year 7 2003 5,969 - -
5,969
Year 8 2004 6,239 - -
6,239
Year 9 2005 6,098 - -
6,098
Year 10 2006 5,990 - -
5,990
10 - 15 year baseline average gross water use 6,058
5 Year Baseline - Gross Water Use
Year 1 2004 6,239 - -
6,239
Year 2 2005 6,098 - -
6,098
Year 3 2006 5,990 - -
5,990
Year 4 2007 6,416 - -
6,416
Year 5 2008 6,269 - -
6,269
5 year baseline average gross water use 6,203
2015 Compliance Year - Gross Water Use
2015 4,721 - - - 4,721
* NOTE that the units of measure must remain consistent throughout the UWMP, as reported in Table 2-3
2015 Urban Water Management Plan
3-15
SB X7-7 Table 4-A: Volume Entering the Distribution System(s)
Complete one table for each source.
Name of Source Salinas Reservoir
This water source is:
The supplier's own water source
A purchased or imported source
Baseline Year
Fm SB X7-7 Table 3
Volume
Entering
Distribution
System
Meter Error
Adjustment*
Optional
(+/-)
Corrected
Volume
Entering
Distribution
System
10 to 15 Year Baseline - Water into Distribution System
Year 1 1997 4186.75 4,187
Year 2 1998 5038.24 5,038
Year 3 1999 4951.54 4,952
Year 4 2000 4863.9 4,864
Year 5 2001 3255.14 3,255
Year 6 2002 3169.55 3,170
Year 7 2003 3730.5 3,731
Year 8 2004 3063.1 3,063
Year 9 2005 1083.37 1,083
Year 10 2006 1659.35 1,659
5 Year Baseline - Water into Distribution System
Year 1 2004 3063.1 3,063
Year 2 2005 1083.37 1,083
Year 3 2006 1659.35 1,659
Year 4 2007 1638.78 1,639
Year 5 2008 2437.43 2,437
2015 Compliance Year - Water into Distribution System
2015 492 492
* Meter Error Adjustment - See guidance in Methodology 1, Step 3 of Methodologies
Document
2015 Urban Water Management Plan
3-16
SB X7-7 Table 4-A: Volume Entering the Distribution System(s)
Complete one table for each source.
Name of Source Whale Rock Reservoir
This water source is:
The supplier's own water source
A purchased or imported source
Baseline Year
Fm SB X7-7 Table 3
Volume
Entering
Distribution
System
Meter Error
Adjustment*
Optional
(+/-)
Corrected
Volume
Entering
Distribution
System
10 to 15 Year Baseline - Water into Distribution System
Year 1 1997 1732.84 1,733
Year 2 1998 525.48 525
Year 3 1999 1061.13 1,061
Year 4 2000 991.47 991
Year 5 2001 2383.39 2,383
Year 6 2002 2693.78 2,694
Year 7 2003 2097.79 2,098
Year 8 2004 3036.21 3,036
Year 9 2005 4867.53 4,868
Year 10 2006 4198.09 4,198
5 Year Baseline - Water into Distribution System
Year 1 2004 3036.21 3,036
Year 2 2005 4867.53 4,868
Year 3 2006 4198.09 4,198
Year 4 2007 4676.77 4,677
Year 5 2008 3744.27 3,744
2015 Compliance Year - Water into Distribution System
2015 1,743 1,743
* Meter Error Adjustment - See guidance in Methodology 1, Step 3 of Methodologies
Document
2015 Urban Water Management Plan
3-17
SB X7-7 Table 4-A: Volume Entering the Distribution System(s)
Complete one table for each source.
Name of Source Groundwater
This water source is:
The supplier's own water source
A purchased or imported source
Baseline Year
Fm SB X7-7 Table 3
Volume
Entering
Distribution
System
Meter Error
Adjustment*
Optional
(+/-)
Corrected
Volume
Entering
Distribution
System
10 to 15 Year Baseline - Water into Distribution System
Year 1 1997 300.17 300
Year 2 1998 289.21 289
Year 3 1999 159.46 159
Year 4 2000 265.83 266
Year 5 2001 246.98 247
Year 6 2002 168.11 168
Year 7 2003 140.46 140
Year 8 2004 139.63 140
Year 9 2005 147.52 148
Year 10 2006 133.04 133
5 Year Baseline - Water into Distribution System
Year 1 2004 139.63 140
Year 2 2005 147.52 148
Year 3 2006 133.04 133
Year 4 2007 100.75 101
Year 5 2008 86.88 87
2015 Compliance Year - Water into Distribution System
2015 43 43
* Meter Error Adjustment - See guidance in Methodology 1, Step 3 of Methodologies
Document
2015 Urban Water Management Plan
3-18
SB X7-7 Table 4-A: Volume Entering the Distribution System(s)
Complete one table for each source.
Name of Source Nacimiento Reservoir
This water source is:
The supplier's own water source
A purchased or imported source
Baseline Year
Fm SB X7-7 Table 3
Volume
Entering
Distribution
System
Meter Error
Adjustment*
Optional
(+/-)
Corrected
Volume
Entering
Distribution
System
10 to 15 Year Baseline - Water into Distribution System
Year 1 1997 0
Year 2 1998 0
Year 3 1999 0
Year 4 2000 0
Year 5 2001 0
Year 6 2002 0
Year 7 2003 0
Year 8 2004 0
Year 9 2005 0
Year 10 2006 0
5 Year Baseline - Water into Distribution System
Year 1 2004 0
Year 2 2005 0
Year 3 2006 0
Year 4 2007 0
Year 5 2008 0
2015 Compliance Year - Water into Distribution System
2015 2,442 2,442
* Meter Error Adjustment - See guidance in Methodology 1, Step 3 of Methodologies
Document
2015 Urban Water Management Plan
3-19
SB X7-7 Table 5: Gallons Per Capita Per Day (GPCD)
Baseline Year
Fm SB X7-7 Table 3
Service Area
Population
Fm SB X7-7 Table
3
Annual Gross Water
Use
Fm SB X7-7
Table 4
Daily Per Capita
Water Use
(GPCD)
10 to 15 Year Baseline GPCD
Year 1 1997 42,983 6,220 129
Year 2 1998 43,421 5,853 120
Year 3 1999 43,766 6,172 126
Year 4 2000 44,179 6,121 124
Year 5 2001 44,293 5,886 119
Year 6 2002 44,406 6,031 121
Year 7 2003 44,293 5,969 120
Year 8 2004 44,271 6,239 126
Year 9 2005 44,630 6,098 122
Year
10 2006 44,483 5,990 120
10-15 Year Average Baseline GPCD 123
5 Year Baseline GPCD
Baseline Year
Fm SB X7-7 Table 3
Service Area
Population
Fm SB X7-7
Table 3
Gross Water Use
Fm SB X7-7
Table 4
Daily Per Capita
Water Use
Year 1 2004 44,271 6,239 126
Year 2 2005 44,630 6,098 122
Year 3 2006 44,483 5,990 120
Year 4 2007 44,438 6,416 129
Year 5 2008 44,650 6,269 125
5 Year Average Baseline GPCD 124
2015 Compliance Year GPCD
2015 45,802 4,721 92
2015 Urban Water Management Plan
3-20
SB X7-7 Table 6: Gallons per Capita per Day
10-15 Year Baseline GPCD 123
5 Year Baseline GPCD 124
2015 Compliance Year GPCD 92
SB X7-7 Table 7: 2020 Target Method
Target Method Supporting Documentation
Method
1 SB X7-7 Table 7A
Method
2 SB X7-7 Tables 7B, 7C, and 7D
Method
3 SB X7-7 Table 7-E
Method
4 Method 4 Calculator
NOTES: Central Coast Hydrologic Region
SB X7-7 Table 7-A: Target Method 1
10-15 Year Baseline
GPCD 2020 Target GPCD
123 98
2015 Urban Water Management Plan
3-21
SB X7-7 Table 7-E: Target Method 3
Agency May Select
More Than One as
Applicable
Percentage of
Service Area in
This Hydrological
Region
Hydrologic Region
"2020 Plan"
Regional
Targets
Method 3
Regional
Targets (95%)
North Coast 137 130
North Lahontan 173 164
Sacramento River 176 167
San Francisco Bay 131 124
San Joaquin River 174 165
100% Central Coast 123 117
Tulare Lake 188 179
South Lahontan 170 162
South Coast 149 142
Colorado River 211 200
Target
(If more than one region is selected, this value is calculated.) 117
SB X7-7 Table 7-F: Confirm Minimum Reduction for 2020 Target
5 Year
Baseline GPCD
From SB X7-7
Table 5
Maximum 2020
Target1
Calculated
2020 Target2
Confirmed 2020
Target
124 118 117 117
1Maximum 2020 Target is 95% of the 5 Year Baseline GPCD except for suppliers at or below 100
GPCD.
22020 Target is calculated based on the selected Target Method, see SB X7-7 Table 7 and
corresponding tables for agency's calculated target.
NOTES: 117 gpcd is from Target Method 3
2015 Urban Water Management Plan
3-22
SB X7-7 Table 8: 2015 Interim Target GPCD
Confirmed
2020 Target
Fm SB X7-7
Table 7-F
10-15 year Baseline
GPCD
Fm SB X7-7
Table 5
2015 Interim Target
GPCD
117 123 120
SB X7-7 Table 9: 2015 Compliance
Actual 2015
GPCD
2015
Interim
Target
GPCD
Optional Adjustments (in GPCD)
2015 GPCD
(Adjusted if
applicable)
Did
Supplier
Achieve
Targeted
Reduction
for 2015?
Enter "0" if Adjustment Not Used
TOTAL
Adjustments
Adjusted 2015
GPCD Extraordinary
Events
Weather
Normalization
Economic
Adjustment
92 120
-
-
- - 92 92 YES
2015 Urban Water Management Plan
4-1
Salinas Reservoir
Chapter 4: Water Sources
The City is the sole water purveyor within the city limits. This allows the City to maintain uniformity of
water service and distribution standards, and to be consistent in developing and implementing water
policy. As the sole water purveyor, the City maintains control over water quality, distribution, and service
to users of the system, as well as ensuring consistency with the General Plan policies and goals.
The City’s General Plan Water and Wastewater Management Element (WWME), was originally adopted
in 1987. The WWME identifies multiple water sources to meet the City’s projected short and long-term
water demands. Having several sources of water avoids dependence on any one source that may not be
available during a drought or other water supply reduction or emergency. There is generally greater
reliability and flexibility if sources are of different types (such as surface water, recycled water, and
groundwater) and if the sources of one type are in different locations (such as reservoirs in different
watersheds). Consistent with this concept, the City obtains water from multiple sources: Salinas Reservoir
(Santa Margarita Lake), Whale Rock Reservoir, Nacimiento Reservoir, and recycled water from the City’s
Water Resource Recovery Facility (WRRF). Groundwater has also been utilized in the past and is
considered an available supplemental water supply. The following sections discuss each of the City’s
water sources.
4.1 SALINAS RESERVOIR
The Salinas Reservoir (also known as Santa
Margarita Lake) is located on the upper Salinas
River, approximately nine miles southeast of the
community of Santa Margarita. The project was
originally built by the War Department to ensure
an adequate water supply for Camp San Luis
Obispo, as well as the City of San Luis Obispo.
The dam and appurtenances were declared
surplus by the War Department on April 14,
1947 and the U.S. Army Corps of Engineers
assumed responsibility for the facilities. On July
11, 1947, the Corps entered into an agreement
with the San Luis Obispo County Flood Control
and Water Conservation District (District) for the
operation and maintenance of the dam and
related facilities. The City has an agreement
with the Corps for the water from the reservoir.
Operation and Distribution
Salinas Reservoir is formed by a concrete arched dam. Immediately following construction, the reservoir
had an estimated storage capacity of 26,000 acre-feet, surface area of 793 acres, and a drainage area of
112 square miles. As a result of siltation since the original construction, the reservoir capacity has been
reduced.
Water is conveyed from Salinas Reservoir through 48,700 feet (9.2 miles) of 24-inch diameter reinforced
concrete pipe to a three million gallon regulating reservoir at Santa Margarita booster pump station near
the northerly base of Cuesta Grade adjacent to Highway 101. The pipeline is designed to flow by gravity
from the Reservoir to the regulating reservoir when the lake level is above the elevation of 1,267 feet. A
booster pump station at the base of the dam, consisting of two horizontal centrifugal pumps, is capable of
maintaining the rated flow of 12.4 cubic feet per second (cfs) when the water surface elevation falls below
1,267 feet. Three electrically-driven horizontal centrifugal pumps at the Santa Margarita booster station
pump water through 6,810 feet of 24-inch diameter reinforced concrete pipe to the entrance portal of the
Cuesta Tunnel, which runs 5,327 feet through the mountains near Cuesta Grade. From the outlet portal of
the tunnel, water is conveyed through an 18-inch diameter steel pipeline a distance of 5,133 feet to the
City's turnout point. From the turnout, an 18-inch diameter pipe runs 4,180 feet to the site of Reservoir #2
2015 Urban Water Management Plan
4-2
Whale Rock Reservoir
on Stenner Creek Road. From there, a pipeline that varies from 24-inches to 30-inches in diameter
conveys the water by gravity to the water treatment plant 5,930 feet downstream.
The operation and maintenance of the dam and water conveyance system (to the City’s turnout) are the
responsibility of San Luis Obispo County Flood Control and Water Conservation District. The City pays all
operating and capital costs associated with the reservoir and transmission system (excluding any
recreational activities).
4.2 WHALE ROCK RESERVOIR
Whale Rock Reservoir is located on Old Creek
approximately one-half mile east of the community of
Cayucos. The project was planned, designed, and
constructed under the supervision of the State
Department of Water Resources. Construction took
place between October 1958 and April 1961. The
reservoir is jointly owned by the City, the California
Men's Colony, and the California Polytechnic State
University at San Luis Obispo. These three agencies
form the Whale Rock Commission which is
responsible for operational policy and administration of
the reservoir. Day-to-day operation is provided by the
City. The City owns 55.05 percent of the water storage
rights at the reservoir. The remaining water storage
rights are apportioned between the two State agencies with Cal Poly owning 33.71 percent and the
California Men’s Colony owning 11.24 percent.
Operation and Distribution
Whale Rock Reservoir is formed by an earthen dam and was able to store an estimated 40,662 acre-feet
of water at the time of construction. The project facilities consist of a 30-inch pipeline, two pumping
stations, 2.1 miles of trails and a fishing access facility, maintenance facility and offices, and a structure
used as a private residence.
City staff is responsible for ongoing maintenance and operation of the reservoir, including the inlet and
outlet structures, reservoir structural instrumentation, access roads, daily reservoir level readings and
climatological data, reservoir patrol and security, pipelines and pumping stations, water meters, cathodic
protection systems, and other associated duties. Staff also monitors public fishing access to the lake
during trout season (April to November).
The conveyance system delivers water from the reservoir to the Whale Rock Commission member
agencies located between the reservoir and the City. Outlets from the pipeline exist for water deliveries to
Chorro Reservoir and water treatment plant (operated by the California Men's Colony), Cal Poly State
University, the Cayucos water treatment facility and the City's W ater Treatment Plant. In addition, water
can be delivered to the Dairy Creek Golf Course under terms of an agreement between the California
Men’s Colony and the County of San Luis Obispo.
The Whale Rock pipeline is approximately 17 miles long, connecting the reservoir to the member
agencies, and terminates at the City's water treatment plant. The design capacity of the pipeline is 18.94
cubic feet per second (approximately 8,500 gallons per minute). The line consists of modified pre-
stressed concrete cylinder pipe at most locations. Cement mortar lined steel pipe is used at creek
crossings and junctions. The pipeline has surge protection consisting of eight-inch, globe type,
diaphragm-actuated pressure relief valves which protect the line from excessive pressures. The cathodic
protection system consists of sacrificial anodes and test stations located in areas subject to galvanic
corrosion. Previous inspections made during routine maintenance and repairs indicate the pipeline to be
in good condition. A pipeline condition analysis project will be conducted in the near future to identify
possible pipeline deficiencies and maintenance activities designed to ensure reliable water delivery.
2015 Urban Water Management Plan
4-3
Two pump stations transmit the water along the pipeline to member agencies. The first pump station is
located in Cayucos at Chaney Way (elevation 44 feet). The second station is located near Camp San Luis
Obispo, approximately six miles southeast of Morro Bay (elevation 181 feet). Each station has five 200
horsepower pumps which are capable of delivering various flow rates requested by member agencies.
Upgrades to both pump stations, which included the addition of two pumps at each station, were
completed in August 1993. Six pumps and motors were replaced in 2004.
Operating Agreements
Several agreements establish policies for the operation of the Whale Rock system and actions of the
member agencies. A brief description of the existing agreements follows:
A) Agreement for the construction and operation of the Whale Rock Project, 1957, set forth the
project's capital cost distribution to the member agencies.
B) A supplemental operating agreement, 1960, established the Whale Rock Commission and
apportioned the operating costs.
C) Downstream water rights agreement (original 1958 agreement was amended and replaced
with a new agreement in April 1996) established water entitlements for adjacent and
downstream water users. The downstream water users (Cayucos Area Water Organization or
CAWO) affected by this agreement consist of three public water purveyors and the cemetery.
In addition to the agencies, water entitlements were identified for separate downstream land
owners.
D) A decision and order by the Fish and Game Commission of the State of California, October
24, 1964, required the Whale Rock Commission to stock the reservoir with 17,500 rainbow
trout (between six and eight inches long) each year. The State Department of Fish and Game
has directed that no fish be planted in the reservoir to protect the existing fish population in
the reservoir (landlocked steelhead)
E) Superior Court decision #36101, 1977, required the Whale Rock Commission to allow public
entry to the reservoir for fishing. In 1981, construction was completed on access trails and
sanitary facilities at the reservoir, and public fishing began at the lake. Entitlements are as
follows:
Downstream Water Users Allocation
Cayucos Area Water Organization ("CAWO") 600 acre-feet
Paso Robles Beach Water Association 222
Morro Rock Mutual Water Company 170
County Water District #10A 190
Cayucos-Morro Bay Cemetery District 18
Mainini 50
Ogle 14
Total Downstream Entitlement: 664 acre-feet
Source: City of San Luis Obispo Utilities Department, 2016.
F) An agreement for water allocation and operational policy between the agencies forming the
Whale Rock Commission. The agreement established the accounting procedures to allow
each agency to carry over excess or deficit water each year. The operating policies were
amended in 1996 to allow agencies to utilize their water supplies in the reservoir as needed
by their agency.
2015 Urban Water Management Plan
4-4
G) An agreement between the Whale Rock Commission and the California Men's Colony, 1990,
to establish maintenance and operation criteria for the Chorro Booster pumps. The Chorro
Booster pumps were installed by the Commission on the California Men's Colony turnout
from the Whale Rock line to reduce system pressures required to provide full flow to the
California Men's Colony water treatment plant. Pump station maintenance, per the
agreement, is the responsibility of the California Men's Colony.
H) An agreement between the Whale Rock Commission and the County of San Luis Obispo for
connection to the Whale Rock pipeline, 1995, allowed a pipeline connection to deliver water
to the Dairy Creek Golf Course. Typically, the golf course uses reclaimed water from the
California Men’s Colony Wastewater Treatment Plant. Water from Whale Rock Reservoir can
be delivered when reclaimed water is not available under the terms of the agreement.
I) A consent to common use agreement, 1996, between the Whale Rock Commission and the
County of San Luis Obispo. The agreement allowed the installation of the State Water
pipeline at seven locations within the existing Whale Rock pipeline easement.
J) An agreement, 2006, for exchange of water between the City of San Luis Obispo and the San
Luis Obispo County Service Area No. 10A. The agreement allows for the exchange of up to
160 acre feet per year of Nacimiento water for water from Whale Rock Reservoir. County
Service Area 10A currently only has an entitlement of 40 acre feet from the Nacimiento
Project.
4.3 NACIMIENTO RESERVOIR
In 1959, the San Luis Obispo Flood Control and Watershed Protection District entered into an agreement
with Monterey County Flood Control and Water Conservation District (now Monterey County Water
Resources Agency) to secure rights to 17,500 acre-feet of water per year from Nacimiento Reservoir.
Nacimiento Reservoir is located entirely within San Luis Obispo County, California (County), and was built
by Monterey County Flood Control and Water Conservation District who continues to control reservoir
ownership and operations. The reservoir has a storage capacity of 377,900 acre-feet and serves the
purpose of abating seawater intrusion in the groundwater aquifers of the Salinas River Valley. The
Nacimiento Reservoir also provides flood protection and is a source of water supply for groundwater
recharge for the Salinas Valley. 1,750 AFY of the County’s entitlement have been designated for uses
around the lake, leaving 15,750 AFY for allocation to other areas within the County of San Luis Obispo.
The “dependable yield” from Nacimiento Reservoir is the contractual amount of water that the City has
rights to from Nacimiento Reservoir. The original amount contracted for was 3,380 acre-feet per year.
Engineering studies, environmental impact reports, dependable yield analyses, and preliminary design
reports were undertaken in an effort to meet the various water needs within the County. In 2004, the
County requested interested agencies to approve the contractual agreements for participation in the
Nacimiento Project. The four initial project participants included the cities of San Luis Obispo and Paso
Robles, the Atascadero Mutual Water Company, and the Templeton Community Services District. All of
these agencies executed participation agreements with San Luis Obispo County for entitlements of water
which totaled 9,630 acre feet. On June 29, 2004, the City Council authorized participation in the
Nacimiento Water Project for the delivery of the original 3,380
acre-feet of water. In 2004, the County Service Area 10A in
Cayucos became a project participant (25 AFY).
The County began construction in 2007 on a 45-mile pipeline
project to deliver water from the Nacimiento Reservoir to
participating agencies and cities. The facilities consist of a
multi-port intake structure, three pump stations, three storage
tanks, 45 miles of pipeline, four turnouts, a control center, and
a Supervisory Control and Data Acquisition (SCADA) and
Project control system. The Project budget was $176-million,
including design, construction, construction management,
2015 Urban Water Management Plan
4-5
environmental permitting, and right-of-way. Pipeline construction and related water delivery facilities were
completed in the fall of 2010 with water deliveries to the City beginning in January of 2011.
In March 2016, the City Council approved the addition of 2,102 afy from Nacimiento Reservoir to the
City’s secondary water supply. This addition brought the City’s total Nacimiento Reservoir Allocation to
5,482 afy. Secondary water supplies are used to meet short-term losses to the City’s water supply due to
events such as drought, pipeline maintenance, and repair of infrastructure. With uncertainty of future
climatic conditions, regulation and aging infrastructure, the additional supply of Nacimiento water to the
City’s portfolio reduces pressure on use of water supplies in the Whale Rock and Salinas reservoirs. It
would serve to extend these stored supplies during future critical water shortage periods.
4.4 GROUNDWATER
The principal source of groundwater for the City is the San Luis Obispo Valley Groundwater Basin. The
basin is fifteen square miles and is drained by San Luis Obispo Creek. It extends from the northern limits
of the City and continues southerly along the alignment of the creek to just south of Buckley Road. In the
Los Osos Valley area, the basin extends four miles west to the Los Osos Basin, which includes the
community of Los Osos/Baywood Park.
The City's major source of water was groundwater and local creeks until 1944 when the City began to use
water from Salinas Reservoir. In 1943, the City pumped 1,380 acre-feet of groundwater. Groundwater
was used again during the summer of 1948, when 440 acre-feet was pumped. From that point on until
1989, most groundwater in the City was used by agriculture and very little was used for domestic
consumption. As a result of the drought beginning in 1986 and decreasing surface water supplies, the
City activated groundwater wells in 1989 to meet the City's water demand. In 1990, at the height of the
drought, the City had seven potable wells which accounted for approximately 50 percent of the water
supplied during that period.
2015 Urban Water Management Plan
4-6
Current groundwater use includes one non-potable well and two irrigation wells. The City's municipal
groundwater well is offline. The Corp Yard well was established during the drought of 1987-91 to serve as
an alternative source of water for construction-related activities prior to the City’s recycled water program.
Over the years, the well, which was minimally monitored, was used by both San Luis Obispo citizens and
properties from outside the City for various purposes ranging from landscape irrigation to water for
livestock. Because of the current extreme drought conditions, many property owners from outside the City
limits have become reliant on the well for domestic non-potable water uses such as flushing toilets. The
City placed limitations on the use of the Corp Yard well in 2015 and it is only available for use under a
valid permit issued by the City. Two wells are still in use for irrigation at the City’s golf course.
TABLE 16: City Wells
Well Name Location Use
Pacific Beach #1 11950 Los Osos Valley Road Potable, Offline
Corp Yard 25 Prado Road Non-potable
Laguna Golf Course #1 11175 Los Osos Valley Road Irrigation
Laguna Golf Course #2 11175 Los Osos Valley Road Irrigation
Source: City of San Luis Obispo Utilities Department, 2016.
Consistent with Policy A 3.2.3 from the City’s General Plan Water and Wastewater Management Element,
the City does not rely on groundwater to meet long-term water demand. In 2015, the City relied on
groundwater to supply 43 acre-feet of potable water. Table 17 shows the City’s groundwater production
for 2011 through 2015. The City will continue to use groundwater for domestic purposes, though as this
source is only being used minimally at present, Table 19 does not identify any City groundwater
production in the future. These production amounts do not include agricultural and private groundwater
pumping by others.
The Sustainable Groundwater Management Act (SGMA) is a statewide policy that empowers local
agencies to adopt groundwater management plans that relate to the needs and resources of their
communities. In the future, the City sees groundwater continuing to play an important and useful role in
the balancing of its overall water supply portfolio. As of May 2016, preliminary studies are underway but
the quantity of groundwater available is unknown at this time.
No groundwater management plan has been prepared for the basin; however, the basin has been defined
to be in overdraft and is listed as a medium priority basin under SGMA. Associated with this listing is the
requirement to form a Groundwater Sustainability Agency by mid-2017 and create a Groundwater
Sustainability Plan by 2022.
TABLE 17: City Groundwater Production
Basin Name 2011 2012 2013 2014 2015
San Luis Obispo Valley (Basin 3-9) 100.08 92.68 76.66 125.58 43.46
NOTES:
1. Water volumes are in acre-feet per year.
2. Department of Water Resources, Table 6-1.
Source: City of San Luis Obispo Utilities Department, 2016.
2015 Urban Water Management Plan
4-7
4.5 WATER SUPPLY SUMMARY
The following tables provide information for each source of water utilized by the City in 2015. The City
utilized water from its multi-source supply in a coordinated manner. Conceptually, the City will use its
contractual water supply from Nacimiento Reservoir first, with Whale Rock and Salinas used as needed to
meet the City’s overall potable water demand. In 2016, this contractual water supply was increased from
3,380 acre-feet to 5,482 acre-feet annually, with the additional 2,102 acre-feet as a secondary water
supply for use during water shortages. In the year projected by this UWMP, the City assumes it will
continue to use these water supplies in this coordinated manner. Recycled water was used at over 40
metered locations for landscape irrigation and construction water uses.
TABLE 18: 2015 Actual Water Supplies
Water Supply Sources
2015 Water purchased from:
SLO County Flood Control and Water Conservation District (Nacimiento Reservoir) 2,677
Supplier-produced groundwater 43
Supplier-produced surface water (Salinas and Whale Rock Reservoirs) 2,000
Recycled Water 187
Total 4,908
NOTES:
1. Water volumes are in acre-feet per year, and rounded to the nearest acre-foot.
2. Department of Water Resources, Table 6-8.
Source: City of San Luis Obispo Utilities Department, 2016.
TABLE 19: Actual and Projected Water Supplies
Water Supply Sources
2020 2025 2030 2035 Water purchased from: Wholesaler supplied
volume (yes)
SLO County Flood Control and
Water Conservation District All 5,482 5,482 5,482 5,482
Supplier-produced groundwater 0 0 0 0
Supplier-produced surface water 626 939 1,265 1,611
Recycled Water 250 300 350 400
Total 6,358 6,721 7,097 7,493
Projected Population: 48,826 51,317 53,934 56,686
NOTES:
1. Water volumes are projected using population projections from Table 2.
2. Water volumes are in acre-feet per year.
3. Department of Water Resources, Table 6-8 and 6-9.
Source: City of San Luis Obispo Utilities Department, 2016.
4.6 TRANSFERS AND EXCHANGE OPPORTUNITIES
The City of Morro Bay and the Whale Rock Commission (which the City of San Luis Obispo is a member
agency) executed an agreement in June of 2000 which provides for Mutual Aid between the agencies
during disruption of water deliveries or lack of available water supplies. The agreement provides a
general framework for exchanging water between agencies in the event of emergencies or other water
disruptions. The agreement is voluntary based on each agency’s ability to assist at any point in the future.
2015 Urban Water Management Plan
4-8
The City is also a member of the California Water/Wastewater Agency Response Network (CalWARN).
This organization functions in coordination with the State Office of Emergency Services (OES) to support
and promote statewide emergency preparedness, disaster response, and mutual assistance matters for
public and private water and wastewater utilities.
The San Luis Obispo County Service Area No. 10 (Cayucos) and the City have a water exchange
agreement which was executed in October of 2006. The agreement allows for an exchange of Whale
Rock Reservoir water for an equal amount of Nacimiento Lake water. The agreement allows for a future
maximum exchange amount of up to 160 afy. The County Service Area No. 10A is a participant in the
Nacimiento Project for a maximum entitlement of 40 afy and the Bella Vista Mobile Home Park, also a
Nacimiento Project participant, may receive a maximum of 10 afy. Therefore, the table below reflects the
current maximum exchange amount of 50 acre feet per year.
TABLE 20: Transfer and Exchange Opportunities
Transfer Agency Transfer or
Exchange
Short-term or
long-term
Proposed
Volume
City of Morro Bay (emergency supply) Transfer Short-Term unknown
San Luis Obispo County Service Area No.10 Exchange Long-Term 50
Total 50
NOTES:
1. Water volumes are in acre-feet per year.
Source: City of San Luis Obispo Utilities Department, 2016.
4.7 FUTURE WATER PROJECTS
In 2004, the City entered into an agreement with San Luis Obispo County to participate in the Nacimiento
Pipeline Project. Water deliveries from the Nacimiento Reservoir began in January 2011. According to the
City’s water supply accounting policies, the City’s water supply will satisfy the need of existing and future
residents and businesses as identified in the City’s General Plan adopted in 2014. The City Council
elected to take the full allocation of Nacimiento in March 2016 adding an additional 2,102 afy to the City’s
water supply portfolio to ensure water supply resiliency.
The City is studying the expansion of its current potable groundwater program.
As described further in Chapter 5, the design phase for the upgrade of the W RRF is underway in 2016 to
accommodate General Plan buildout and maximize recycled water production. The upgrade will enable
the City to pursue potable reuse in the future.
4.8 DESALINATED WATER OPPORTUNITIES
Desalination is a viable technology which is not rainfall dependent. Desalination activities can have
significant negative environmental impacts and significant energy requirements which drive up the cost of
desalinized water. The major disadvantages of desalination are the cost, potential for environmental
impacts, and significant energy demand. Desalination is currently being used or considered for use by
multiple local agencies and could potentially be a water supply consideration in the future if the City’s
current supplies prove to be inadequate or insufficiently resilient. Desalination is not being pursued by the
City at this time although future advances in desalination technology may create opportunities to utilize
this resource.
2015 Urban Water Management Plan
4-9
4.9 Required UWMP Standardized Tables:
Retail: Groundwater Volume Pumped
Groundwater Type Location or Basin Name 2011 2012 2013 2014 2015
Alluvial Basin San Luis Obispo Valley 100.08 92.68 76.66 125.58 43.46
TOTAL 100 93 77 126 43
NOTES: Table 6-1 R.
Retail: Water Supplies — Actual
Water Supply Additional Detail on
Water Supply
2015
Actual Volume Water Quality
Surface water Nacimiento Reservoir 2,677 Drinking Water
Surface water Whale Rock Reservoir 1,461 Drinking Water
Surface water Salinas Reservoir 539 Drinking Water
Groundwater San Luis Basin 43 Drinking Water
Recycled Water City of San Luis Obispo WRRF 187 Recycled Water
Total 4,908
NOTES: Table 6-8 R.
Water Supplies — Projected
Water Supply
Additional
Detail on Water
Supply
Projected Water Supply
2020 2025 2030 2035
Reasonably
Available
Volume
Reasonably
Available
Volume
Reasonably
Available
Volume
Reasonably
Available
Volume
Surface water Nacimiento
Reservoir
5,482
5,482
5,482
5,482
Surface water
Salinas Reservoir
and Whale Rock
Reservoir
6,940 6,940 6,940 6,940
Recycled Water City of San Luis
Obispo WRRF 200 250 300 350
Total 12,622 12,672 12,722 12,772
NOTES: Table 6-9 R (Retail).
2015 Urban Water Management Plan
5-1
Chapter 5: Recycled Water
This chapter was prepared to fulfill the
requirements of Section 10633 (a-g) of California
Water Code Division 6, Article 2, Part 2.6 regarding
the City’s recycled water supply. As defined in
Water Code Section 13050(n),
“Recycled Water” means water which as, a
result of treatment of waste, is suitable for
a direct beneficial use or a controlled use
that would not otherwise occur and is
therefor considered a valuable resource.
The City produces and distributes recycled water consistent with the regulatory requirements described
below and therefore meets the minimum requirements to be classified as recycled water in this UWMP.
These regulations, as set forth in Title 22, Division 4 of the California Code of Regulations, Wastewater
Recycling Criteria (Title 22) and the conditions and requirements contained in the City’s National Pollutant
Discharge Elimination System (NPDES) Permit Number R3-2003-081 prescribed by the RWQCB,
establish specific criteria for treatment, distribution, and application of recycled water within the state. The
RWQCB and Division of Drinking Water (DDW) have a memorandum of understanding in which DDW
agrees the RWQCB will be the implementing agency responsible for permitting recycled water programs.
The RWQCB Master Permit for Recycled Water is the guiding document for most of the City’s
requirements. In accordance with the Master Permit (WDR Order No. 03-2003-081, October 24, 2003),
the City complies with the following:
1. Meter the total quantity of reclaimed water distributed daily,
2. Monitor and record chlorine residual concentration at a point after the final chlorine contact
basin,
3. Provide guidance to recycled water users including a user manual and other guidance as
needed,
4. Provide instruction to all City field staff to report incidents of unauthorized daytime irrigation
activity or runoff,
5. Cooperate with County Environmental Department of Health Services to ensure backflow
devices are present, tested and repaired or replaced if found defective,
6. Inspect the operation of reuse sites,
7. Perform cross connection testing,
8. Conduct site supervisor training and quarterly interviews to verify system operation, and
9. Quarterly review of monthly meter readings with follow-up on change in patterns of use.
The City also complies with minimum daily average discharge requirements from the WRRF to San Luis
Obispo Creek for protection of downstream biological resources as required by National Oceanic
Atmospheric Association, National Marine Fisheries Service (NOAA NMFS).
5.1 WASTEWATER COLLECTION, TREATMENT, AND DISPOSAL
The City’s wastewater collection system serves residential, commercial and industrial customers within
the city limits. The City also provides service to Cal Poly and the County of San Luis Obispo Airport. The
City’s WRRF is located on Prado Road, adjacent to U.S. 101 in the southern portion of the City. The
design flow rate at the W RRF is 5.1 million gallons per day (MGD), with a 2015 average daily flow of 2.74
MGD. The WRRF discharges to San Luis Obispo Creek.
The City’s Water Reuse Project, which included improvements at the WRRF and the construction of eight
miles of recycled water distribution system, was completed in October of 2006. The recycled water pump
station was designed to provide up to 1,750 gallons per minute (gpm) of recycled water at a pressure of
approximately 130 pounds per square inch (psi). Maximum design capacity is approximately 2.5 MGD.
2015 Urban Water Management Plan
5-2
TABLE 21: Recycled
Water Usage
2011-2015
Year Usage
(in acre feet)
2011 77.17
2012 89.95
2013 138.07
2014 152.63
2015 187.4
Source: City of San Luis
Obispo Utilities
Department, 2016.
The distribution system was designed to serve the City with one pressure zone. Recycled water storage is
provided by one-600,000 gallon underground storage tank located at the W RRF. The existing recycled
water pump station was designed to accommodate future expansion with space for two additional pumps at
the WRRF.
The recycled water distribution system extends to the east and west from the
WRRF in the southern portion of the City (See Figure 5). The distribution
system was designed to supply irrigation water to several existing City parks,
the City’s Laguna Lake Golf Course, a middle school, Caltrans landscape
medians, and four future development areas. Recycled water is provided to
Caltrans from a metered connection near the WRRF, which is adjacent to U.S.
Highway 101. Caltrans utilizes recycled water to irrigate landscape areas
along the entire highway corridor through the City, which was previously
supplied with potable water. Annual usage for 2011 through 2015 is provided
in Table 21.
The City’s W RRF produced over 3,000 acre-feet of disinfected tertiary-treated
effluent in 2015. The City is required to maintain a minimum average daily
release, year-round, of treated effluent to San Luis Obispo Creek at a rate of
2.5 cubic feet per second (cfs), or approximately 1.6 mgd to provide a flow
volume adequate to support habitat for anadromous fish species within San
Luis Obispo Creek. This rate totals a minimum of 1,807 acre feet per year of
creek discharge. The City monitors the release of effluent through an effluent
meter at the WRRF. The balance, approximately 1,250 acre feet in 2015,
makes up the City’s available recycled water resource (See Table 22).
The design phase for the upgrade of the W RRF to accommodate buildout under the City’s General Plan
and maximize recycled water production is underway in 2016. When the W RRF is expanded in the future
it will have an estimated treatment capacity of 5.4 mgd. The upgrade will enable the City to consider
potable reuse in the future. Potable reuse is discussed more in section 5.7 of this Chapter.
5.2 CURRENT RECYCLED WATER USE
In 2015, recycled water was delivered to over 40 metered
locations in the City for landscape irrigation. Additional sites will
continue to be connected to the recycled water distribution
system with new development in the City. Other notable
recycled water demand figures:
• Average Daily Demand in July, August and September
2015 was over 292,000 gallons.
• Peak Daily Demand was over 534,000 gallons on June
17, 2015.
• Peak Monthly Demand was over 9.3 million gallons
during August 2015.
The City began issuing annual construction water permits in
July 2009. During the 2015-16 fiscal year over 40 construction
water permits were sold. Permit holders have access to an
unlimited supply of recycled water for dust control and
compaction on construction sites in the City. The City has
metered wharf head hydrant filling stations on the recycled
water distribution system, at the City’s Corporation Yard and
within the WRRF.
2015 Urban Water Management Plan
5-3
2015 Urban Water Management Plan
5-4
T ABLE 22: 2015 Influent Flow and Recycled Water Availability
Average Influent Flow to
WRF (MGD)
Treated
Effluent
Produced
(AFY)
Minimum Average
Daily Creek
Release (MGD)1
Minimum
Annual Creek
Release (AFY)
Average Daily
Recycled Water
Availability (MGD)
Annual Recycled
Water Availability
(AFY) 1
2015 Average Flow 2.74 3,066 1.6129 1,807 1.13 1,259
Future Flow at
WRRF Design
Capacity
5.4 5,966 1.6129 1,807 3.79 4,159
NOTES:
1. 2015 data was derived from WRRF average monthly influent data. Future annual recycled water volume is based on the
design capacity of the WRRF of 5.4 mgd in the design phase in 2016.
Source: City of San Luis Obispo Utilities Department, 2016.
5.3 FUTURE SYSTEM EXPANSION
This section discusses the City’s 2004 Water Reuse Master Plan (2004 Master Plan) including the
potential for future expansion of the City’s recycled water system, and projected recycled water usage in
2020, 2025 and 2030, and 2035. The City’s 2004 Master Plan included the following goals:
1. Increase the City’s safe annual yield by utilizing recycled water for non-potable purposes,
thereby offsetting the use of potable water.
2. Develop a dependable water supply to meet a portion of the City’s non-potable demand.
3. Efficiently manage the City’s water resources.
4. Provide non-potable water to meet future non-potable demand.
At that time, the City estimated that demand existed for approximately 1,000 acre-feet of recycled water
annually including a 380 AFY groundwater exchange program, serving recycled water for landscape
irrigation to the Orcutt, Margarita, and Airport Specific Plan areas, as well as retrofits of existing irrigation
systems to use recycled water.
A number of factors have changed since the adoption of the 2004 Master Plan related to water demand
and wastewater generation. Per capita water demand is down from 126 gallons per capita per day (gpcd)
in 2004 to 92 gpcd in 2015. The average daily and monthly influent flows to the WRRF have also
decreased since the 2004 Master Plan reported the average flow as 4.5 mgd (a 2003 figure) to 2.74 mgd
in 2015. This average daily flow is further lowered during the summer months while the student
population associated with Cal Poly is away (mid-June to mid-September), thus reducing the available
recycled water supply during the peak irrigation season.
The 2004 Master Plan included a 380 AFY groundwater exchange program whereby the City’s recycled
water supply would be exchanged for a potable ground water supply that was used to irrigate agricultural
land outside the City limits. This included both Dalidio Groundwater Exchange and South Higuera
Groundwater Exchange. Since that time, the City elected not to pursue a groundwater exchange program
due to the significant operating cost of utilizing groundwater supplies. Water deliveries under this
program, which was 38 percent of the projected 1,000 AFY recycled water demand identified in the 2004
Master Plan, was intended to be delivered off-peak from landscape irrigation deliveries.
Projected recycled water use for 2020 through 2035 is provided in Table 23. Table 24 revisits estimates
made in the 2010 UWMP for 2015 and actual 2015 recycled water deliveries.
The City is updating the 2004 Master Plan to address changed conditions experienced since 2004. The
update will provide the City the opportunity to model the expansion of the recycled water distribution
system, update future recycled water users, and planned system expansion.
2015 Urban Water Management Plan
5-5
TABLE 23: Potential Future Recycled Water Use
Beneficial Use Type General Description of 2015 Uses Level of
Treatment 2015 2020 2025 2030 2035
Landscape irrigation
(excludes golf courses) Irrigation at parks, school, medians, etc. Tertiary 128 135 175 200 235
Golf course irrigation Laguna Lake Golf Course Tertiary 17 15 15 15 15
Commercial use Irrigation at commercial sites Tertiary 27 30 35 60 75
Other: Construction Water Construction Water Permit program Tertiary 15 20 25 25 25
Total: 187 200 250 300 350
NOTES:
1. Water volumes are in acre-feet per year.
2. Department of Water Resources, Table 6-4.
3. Projected recycled water usage for 2020 to 2035 is based on the City’s knowledge of planned projects identified in the City’s
General Plan Land Use Element to be served with recycled water (including the Margarita Area, Orcutt Area, Airport Area,
Avila Ranch Area, San Luis Ranch Area, and Madonna on LOVR).
Source: City of San Luis Obispo Utilities Department, 2016.
TABLE 24: 2010 UWMP Recycled Water Use Projection
Compared to 2015 Actual Deliveries
Use Type
2010 Projection
for 2015
2015 Actual
Use
Agricultural irrigation 0 0
Landscape irrigation
(excludes golf courses) 100 128
Golf course irrigation 20 17
Commercial use 80 27
Other: Construction
Water 0 15
Total 200 187
NOTES:
1. From the 2005 Urban Water Management Plan.
2. Includes parks, schools, medians and streetscape, and common
area landscape with residential Home Owners Associations.
3. Includes commercial building landscaping.
4. Water volumes are in acre-feet per year.
5. Department of Water Resources, Table 6-5.
Source: City of San Luis Obispo Utilities Department, 2016.
5.4 RECYCLED WATER PROGRAM INCENTIVES
For approximately five years (2005 to 2010), the City’s Capital Improvement Plan identified $250,000
annually for expansion of the recycled water distribution system and user site modifications of existing
irrigation systems necessary to utilize recycled water. The Master Plan included this strategy for
expanding the use of recycled water in the near term. The strategy was to fund level expenditures each
year and add new users from the existing distribution system. Although this funding is not in place for the
current Financial Plan due to other priorities in the Water Fund, system expansion will continue in the
future until such point that no additional sites are available or are deemed not cost beneficial to retrofit. At
that point, the Council could decide to proceed with additional expansion of the system.
2015 Urban Water Management Plan
5-6
The City adopted a mandatory use ordinance for recycled water in 2004. The policy, codified in the
Municipal Code as Chapter 13.24, allows the City to require the use of recycled water on parcels when
considered feasible. The code language is as follows:
13.24.010 Statement of Policy
When in the judgment of the city, reclaimed water service can be feasibly provided to a
particular parcel for particular uses, the utilities director shall require the use of reclaimed
water in lieu of potable water for those uses. As used herein, the term “feasible” means
reclaimed water is available for delivery to the property in compliance with all applicable
federal, state, and local laws, ordinances and regulations and such reclaimed water can
be delivered to the property at an overall cost to the user which does not exceed the
overall cost of potable water service (Ord. 1403 § 1,2001).
The mandatory use ordinance is an important element of the City’s recycled water program. The
ordinance eliminates the need to provide true financial incentive or economic motivation to small volume
users, which are ultimately expected to make up a significant portion of the City’s overall recycled water
demand. Funding mechanisms or incentives may be required to achieve user site retrofits of existing
irrigation systems.
In 2016, the metered rate charged for recycled water is 90 percent of the potable water rate. A permit to
utilize recycled water for construction is available for an annual fee. These costs will be reviewed by the
City in a rate study in 2016.
5.5 SEASONAL SURPLUS
The City has identified a “seasonal surplus” of recycled water available in excess of required discharge to
the creek (1.6129 million gallons per day or mgd as required by the National Oceanic and Atmosopheric
Association, National Marine Fisheries Service) and recycled water for landscape irrigation. The primary
use of recycled water in the City is for landsacpe irrigation with 76 percent of the City’s recycled water
demand occuring from May through October. During 2015, 187 acre feet of recycled water was used for
landscape irrigation and construction water. As only a limited amount of landscape irrigation takes place
from November to April (seasonal off-peak period), more than 2 mgd of recycled water is available during
the seasonal off-peak period. Related to this seasonal surplus, the following goal and program was added
to the General Plan, Water and Wastewater Management Element in 2010:
Goal A7.1.2 Maximize the use of the City’s available recycled water supply for approved uses.
Program A 7.3.4 Consider the potential to deliver available recycled water supplies to customers outside
the city limits, including analysis of policy issues, technical concerns, and cost recovery,
provided it is found to be consistent with the General Plan.
With the update to the General Plan, Land Use Element in 2014 the following policy was added:
1.13.2. Recycled Water
Provision of recycled water outside of City limits may only be considered in compliance with Water and
Wastewater Element Policy A 7.3.4 and the following findings:
A. Non-potable/recycled water is necessary to support continued agricultural operations.
B. Provision of non-potable/recycled water will not be used to increase development potential of
property being served.
C. Non-potable/recycled water will not be further treated to make it potable.
D. Prior to provision of non-potable/recycled water, the property to be served will record a
conservation, open space, Williamson Act, or other easement instrument to maintain the area
being served in agriculture and open space while recycled water is being provided.
2015 Urban Water Management Plan
5-7
The upgrade of the Water Resource
Recovery Facility will enable the City
to consider potable reuse in the
future, part of a One Water concept.
T ABLE 25: Methods to Expand Recycled Water Use
Name of Action Description Planned
Implementation Year
Expected Increase in
Recycled Water Use
Mandatory Use Ordinance adopted 2004 300
Sale of Seasonal Surplus Under study Unknown Unknown
Potable Reuse Under study Unknown Unknown
Total 300
NOTES:
1. Water volumes are in acre-feet per year.
2. Department of Water Resources, Table 6-6.
Source: City of San Luis Obispo Utilities Department, 2016.
5.6 POTABLE REUSE
The design phase for the upgrade of the W RRF is underway in
2016 to accommodate General Plan buildout and maximize
recycled water production. The upgrade will enable the City to
consider potable reuse, part of a One Water concept, in the future.
Direct potable reuse is the planned introduction of recycled water
either directly into a public water system, as defined in Section
116275 of the Health and Safety Code, or into a raw water supply
immediately upstream of a water treatment plant. Direct potable
reuse is a practice which is not currently occurring in California;
however, the feasibility of implementing direct potable reuse is
currently being reviewed by an expert panel supported by the
DDW. The panel will provide recommendations to the DDW by
December 2016 to:
• Advise DDW on public health issues and scientific and
technical matters regarding the feasibility of developing uniform
water recycling criteria for direct potable reuse.
• Assess what, if any, additional areas of research are needed to be able to establish uniform water
recycling criteria for direct potable reuse.
2015 Urban Water Management Plan
5-8
Indirect potable reuse occurs when tertiary or advanced treated wastewater augments drinking water
resources. The two types of indirect potable reuse are:
• Indirect potable reuse for groundwater recharge ‐ where recycled water recharges a groundwater
basin and groundwater is later extracted from the basin.
• Surface water augmentation – where recycled water is added into a surface water reservoir used as a
source of domestic drinking water supply.
Indirect potable use does not actually occur until the water is subsequently pumped from the ground or
withdrawn from the reservoir, treated, and added to the drinking water distribution system.
Indirect potable reuse through groundwater recharge has occurred in California since 1962. Title 22,
Division 4, Chapter 3, Article 5.1 (CCR §60320 et seq) describes the permitting and monitoring process
required to obtain a RWQCB permit for groundwater recharge. Indirect potable reuse through surface
water augmentation is not currently permitted in California, but regulations are being drafted and are
expected to be completed by December 31, 2016. Like groundwater recharge with recycled water,
surface water augmentation will only occur with a permit and monitoring requirements from a RWQCB.
2015 Urban Water Management Plan
5-9
5.7 Required UWMP Standardized Tables:
Wastewater Collected Within Service Area in 2015
100 Percentage of 2015 service area covered by wastewater collection system (optional)
100 Percentage of 2015 service area population covered by wastewater collection system (optional)
Wastewater Collection Recipient of Collected Wastewater
Name of
Wastewater
Collection Agency
Wastewater
Volume Metered
or Estimated?
Volume of
Wastewater
Collected in
2015
Name of
Wastewater
Treatment Agency
Receiving
Collected
Wastewater
Treatment Plant
Name
Is WWTP
Located
Within
UWMP
Area?
Is WWTP
Operation
Contracted to a
Third Party?
City of
San Luis Obispo Metered 3,066 City of San Luis
Obispo
City of San Luis
Obispo Yes No
Total Wastewater Collected from Service
Area in 2015: 3,066
NOTES: Table 6-2 R.
Wastewater Treatment and Discharge Within Service Area in 2015
Wastewater
Treatment
Plant Name
Discharge
Location
Name or
Identifier
Discharge
Location
Description
Wastewater
Discharge ID
Number
(optional)
Method
of
Disposal
Does This
Plant Treat
Wastewater
Generated
Outside the
Service Area?
Treatment
Level
2015 volumes
Wastewater
Treated
Discharged
Treated
Wastewater
Recycled
Within
Service
Area
Recycled
Outside
of
Service
Area
City of
San Luis
Obispo
Water
Resource
Recovery
Facility
San Luis
Obispo
Creek
Creek
outfall R3-2014-0033
River or
creek
outfall
Yes Tertiary 3,066 2,878 187 0
Total 3,066 2,878 187 0
NOTES: Table 6-3 R.
Wastewater Treatment and Discharge Within Service Area in 2015
Beneficial Use Type General Description of 2015 Uses Level of
Treatment 2015 2020 2025 2030 2035
Agricultural irrigation None 0
Landscape irrigation (excludes golf courses) Irrigation at parks, school, medians,
etc. Tertiary 128 135 175 200 235
Golf course irrigation Laguna Lake Golf Course Tertiary 17 15 15 15 15
Commercial use Irrigation at commercial sites Tertiary 27 30 35 60 75
Other: Construction Water Construction Water Permit program Tertiary 15 20 25 25 25
Total: 187 200 250 300 350
NOTES: Table 6-4 R.
2015 Urban Water Management Plan
5-10
2010 UWMP Recycled Water Use Projection Compared to 2015 Actual
Use Type
2010
Projection for
2015
2015 actual
use
Agricultural irrigation 0 0
Landscape irrigation (excludes golf courses) 100 128
Golf course irrigation 20 17
Commercial use 80 27
Other: Construction Water 0 15
Total 200 187
NOTES: Table 6-5 R.
Retail: Methods to Expand Future Recycled Water Use
Page 5-6 Provide page location of narrative in UWMP
Name of Action Description
Planned
Implementation
Year
Expected Increase in Recycled
Water Use
Mandatory Use Ordinance adopted 2004 300
Sale of Seasonal Surplus Under study Unknown Unknown
Potable Reuse Under study Unknown Unknown
Total 300
NOTES: Table 6-6 R.
Expected Future Water Supply Projects or Programs
No expected future water supply projects or programs that provide a quantifiable increase to the agency's
water supply. Supplier will not complete the table below.
Some or all of the supplier's future water supply projects or programs are not compatible with this table and
are described in a narrative format.
Page 5-6 Provide page location of narrative in the UWMP
NOTES: Table 6-7 R.
2015 Urban Water Management Plan
6-1
Chapter 6: Water Supply Reliability
This chapter discusses the City’s water supply reliability and presents the projected supplies available
during a single dry water year and during multiple-dry water years. As directed by DWR, this chapter was
prepared based on what is known by the City at the time the UWMP was prepared. Actions that would be
undertaken during a short-term water supply emergency, such as drought or a catastrophic supply
interruption, are addressed in the Water Shortage Contingency Plan included in Chapter 8.
The City uses multiple water sources to meet projected short and long-term water demands and
implements water efficiency and demand management measures to balance the long-term reliability.
Having several sources of water avoids dependence on any one source that may not be available during
a drought or other water supply reduction or emergency. There is generally greater reliability and flexibility
if sources are of different types (such as surface water, recycled water, and groundwater) and if the
sources of one type are in different locations (such as reservoirs in different watersheds). Consistent with
this concept, the City obtains water from multiple sources: Salinas Reservoir (Santa Margarita Lake),
Whale Rock Reservoir, Nacimiento Reservoir, and recycled water from the City’s Water Resource
Recovery Facility (WRRF). Groundwater has also been utilized in the past and is considered an available
supplemental water supply. The City does not import water from outside the local region. All components
are necessary to maximize the available water resources.
As a signatory of the California Urban Water Conservation Council’s (CUWCC) Memorandum of
Understanding for Urban Water Conservation since 1991, the City has completed the implementation of
all the Best Management Practices (BMPs) for water retailers. A full discussion of the City’s water
demand management measures are included in Chapter 7.
6.1 SALINAS AND WHALE ROCK RESERVOIRS
For Salinas and Whale Rock Reservoirs, the City uses a computer model to simulate the operation of
these two water supply sources over a historical period to determine “safe annual yield” or the quantity of
water which can be withdrawn every year to accommodate City water demand.
Salinas Reservoir and Whale Rock Reservoir are in geographically and climatologically distinct
watersheds. Salinas Reservoir has a higher evaporation rate and larger watershed than W hale Rock
Reservoir, but smaller storage capacity -- about 60 percent of the storage capacity of Whale Rock
Reservoir. Whale Rock Reservoir has a smaller watershed, as compared to Salinas Reservoir, but
greater storage capacity. Whale Rock experiences a lower evaporation rate as it is close to ocean.
Coordinated operation of the two reservoirs results in maximization of safe annual yield. This approach
increases the long-term water supply from these two sources.
The City’s safe annual yield from the coordinated operation of Salinas and Whale Rock Reservoirs is
6,940 acre feet. As required by General Plan, Water and Wastewater Management Element, policy
A3.3.2:
The City will update the safe annual yield computer model for Salinas and Whale Rock
Reservoirs following severe drought periods to determine if any changes are necessary
to the safe annual yield amount.
After the current drought has a “bookend” the safe annual yield of the reservoirs will be recalculated.
Related changes to safe annual yield will be incorporated into planning scenarios.
6.2 RECYCLED WATER
With a 2015 average influent flow of 2.74 million gallons per day, the City’s WRRF produces over 3,000
acre-feet of disinfected tertiary-treated effluent per year. A minimum of 1,807 acre-feet is discharged to
San Luis Obispo Creek annually to provide satisfactory habitat and flow volume for fish species
2015 Urban Water Management Plan
6-2
(steelhead trout) within the Creek environment. The balance makes up the City’s available recycled water
resource which is available for approved uses.
A consistent flow of wastewater to the W RRF enables the City to produce a volume of recycled water that
exceeds identified seasonal demand for landscape irrigation. Recycled water is considered a reliable
water supply. Information on recycled water is provided in Chapter 5.
6.3 NACIMIENTO RESERVOIR
In 2002, the San Luis Obispo County Flood Control and Water Conservation District (District) retained the
services of Boyle Engineering Corporation to assess the ability of the Nacimiento Reservoir to reliably
provide the District’s entitlement of 17,500 acre feet per year to the District contractors. As part of the
analysis, the study took into account the agreement with the Monterey County Water Resources Agency
(MCWRA), which owns and operates the Nacimiento Reservoir facilities, that stipulates that the District
entitlement through operational procedures will be “preserved” in the reservoir due to MCWRA being
contractually obligated to maintain a “minimum pool” for the
benefit of the District. This enables the District to maintain
deliveries to the participating agencies even when reservoir
levels are low, meaning that unless the water storage
capacity drops below the “dead pool” of the reservoir, the
District’s entitlement will always be available. The study
took into account the following factors:
• Short-term power outages
• Delivery facility failure
• Energy costs
• Drought
• Contamination of supply
• Environmental restrictions
Upon completion of the analysis relating to drought conditions, the study summarized that even though
there have been several periods of drought, both short-term and long-term, the total annual entitlement
for the District could be delivered.
During the worst case drought on record (2012 to 2014), Nacimiento Reservoir continues to be a resilient
water supply capable of providing a consistent and reliable source of water for San Luis Obispo County
which includes the City’s contracted amount of 5,482 acre feet per year.
Interlake Tunnel Project
An Interlake Tunnel Project has been proposed by Monterey County to create a connection between Lake
Nacimiento and Lake San Antonio. The goal of the project is to redirect water to fill the excess capacity
typically available in Lake San Antonio. While the Interlake Tunnel Project has the potential to increase
water storage up to 60,000 afy in Lake San Antonio, it is unclear if the diversion from Lake Nacimiento
would result in any changes in reliability to water availability of the County’s 17,500 afy entitlement. The
City will be closely monitoring the project to ensure its water rights are protected.
6.4 GROUNDWATER
Consistent with Policy A 3.2.3 from the City’s General Plan, Water and Wastewater Management
Element, the City will continue to use groundwater for domestic purposes when available. As described in
Chapter 4, groundwater may be available to the City as a supplemental supply during a water shortage
emergency. In 2016, The City is planning capital improvements to enhance the City’s ability to extract,
treat, and utilize groundwater to meet a portion of the City’s potable water demand.
2015 Urban Water Management Plan
6-3
The San Luis Obispo Valley Basin has been defined to be in overdraft and is listed as a medium priority
basin under SGMA. Associated with this listing is the requirement to form a Groundwater Sustainability
Agency by mid-2017 and create a Groundwater Sustainability Plan by 2022.
6.5 WATER QUALITY
A summary of the water quality from the City’s various water sources is provided in Table 26. The City
has no known water quality constraints that would make a water source unavailable for potable water
use. The City’s 2015 Annual Water Quality Report is provided in Appendix V.
TABLE 26: Water Quality
Current and Projected Water Supply Impacts
Water Source Water Quality
Nacimiento Reservoir Drinking Water
Salinas Reservoir Drinking Water
Whale Rock Reservoir Drinking Water
Groundwater Drinking Water
Recycled Water Title 22, Tertiary Treated Recycled Water
Source: City of San Luis Obispo Utilities Department, 2016.
6.6 WATER SUPPLY RELIABILITY ANALYSIS
A regulatory requirement of the UWMP is to perform a water supply reliability analysis applying different
worst case drought years according to stringent guidelines set forth in the UWMP plan documentation.
The following tables provide data on the reliability of the City’s water supply during normal, single-dry, and
multiple-dry water years. The City is confident in the reliability of its multi-source water supply portfolio.
Table 27 lists the years which correlate to the guidelines for the specific water year type and are based on
rainfall information dating back to the year 1870. The City’s average water year was determined to be
1943 as rainfall totals most closely compared to the City’s average rainfall total. The City’s single dry
water year was determined to be 2013 as the rainfall total in 2013 was the lowest on record. The City’s
multiple dry year scenario was determined to be 2012 to 2014 as the combined rainfall total for those
three years was the lowest on record.
TABLE 27: Basis of Water Year Data
Water Year Type Base Year(s) Volume Available
Average Water Year 1943 12,622
Single-Dry Water Year 2013 12,622
Multiple-Dry Water
Years, 1st year 2012 12,622
Multiple-Dry Water
Years, 2nd year 2013 12,622
Multiple-Dry Water
Years, 3rd year 2014 12,622
NOTES
1. Department of Water Resources, Table 7-1.
2. Units are in acre-feet per year.
3. Volume available includes the City’s contractual supply to Nacimiento
Reservoir, Safe Annual Yield from Salinas and Whale Rock Reservoirs, and
recycled water.
Source: City of San Luis Obispo Utilities Department, 2016.
2015 Urban Water Management Plan
6-4
The City makes projections of future water demand using a conservative per capita potable water use
rate of 117 gpcd which is the City’s SB X7-7 target. Table 28 summarizes the results of that analysis
which, based on the City’s available water supplies and estimates of future water demand, indicates the
City’s water resources are reliable during extended drought periods.
TABLE 28: Supply and Demand Comparison
Normal Year
2020 2025 2030 2035
Supply totals 12,622 12,672 12,722 12,772
Demand totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
NOTES
1. Department of Water Resources, Table 7-2.
2. Units are in acre-feet per year.
3. Supply total includes the City’s contractual supply to Nacimiento Reservoir, Safe
Annual Yield from Salinas and Whale Rock Reservoirs, and recycled water use
which will increase over time.
Source: City of San Luis Obispo Utilities Department, 2016.
Table 29 and Table 30 summarize the City’s water supplies in a single dry year and a multiple dry year
scenario.
T ABLE 29: Single Dry Year Supply and Demand Comparison
2020 2025 2030 2035
Supply totals 12,622 12,672 12,722 12,772
Demand totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
NOTES
1. Units are in acre-feet per year.
2. Department of Water Resources, Table 7-3.
3. Demand totals are projected using 117 gpcd.
Source: City of San Luis Obispo Utilities Department
2015 Urban Water Management Plan
6-5
TABLE 30: Multiple Dry Year Supply and Demand Comparison
2020 2025 2030 2035
First year
Supply totals 12,622 12,622 12,622 12,622
Demand totals 6,314 6,001 5,675 5,329
Difference 6,308 6,621 6,947 7,293
Second year
Supply totals 12,622 12,622 12,622 12,622
Demand totals 6,314 6,001 5,675 5,329
Difference 6,308 6,621 6,947 7,293
Third year
Supply totals 12,622 12,622 12,622 12,622
Demand totals 6,314 6,001 5,675 5,329
Difference 6,308 6,621 6,947 7,293
NOTES
1. Department of Water Resources, Table 7-4.
2. The urban water targets determined in this UWMP were considered when developing the 2020
water demands included in this table.
Source: City of San Luis Obispo Utilities Department
The City’s General Plan, W ater and Wastewater Management Element, identifies policies that create a
Reliability Reserve and Secondary Water Supply in an effort to reduce the impacts of a water shortage on
the community. The Reliability Reserve, found in the City’s Charter, provides 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 City’s secondary
water supply is the amount needed to meet peak water demand periods or short-term loss of City water
supply sources. The City’s Secondary Water Supply is identified as any water supply resources above
those needed to meet the primary water supply and reliability reserve.
6.7 Required UWMP Standardized Tables:
Basis of Water Year Data
Year Type Base Year
Available Supplies if
Year Type Repeats
Agency may provide volume only, percent only, or both
Volume Available % of Average Supply
Average Year 1943 12,622 100%
Single-Dry Year 2013 12,622
Multiple-Dry Years 1st Year 2012 12,622
Multiple-Dry Years 2nd Year 2013 12,622
Multiple-Dry Years 3rd Year 2014 12,622
NOTES: Table 7-1(R)
2015 Urban Water Management Plan
6-6
Normal Year Supply and Demand Comparison
2020 2025 2030 2035
Supply totals
(autofill from Table 6-9) 12,622 12,672 12,722 12,772
Demand totals
(autofill from Table 4-3) 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
NOTES: Table 7-2(R)
Single Dry Year Supply and Demand Comparison
2020 2025 2030 2035
Supply totals 12,622 12,672 12,722 12,772
Demand totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
NOTES: Table 7-3(R)
Multiple Dry Years Supply and Demand Comparison
2020 2025 2030 2035
First year
Supply totals 12,622 12,672 12,722 12,772
Demand
totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
Second year
Supply totals 12,622 12,672 12,722 12,772
Demand
totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
Third year
Supply totals 12,622 12,672 12,722 12,772
Demand
totals 6,599 6,975 7,369 7,779
Difference 6,023 5,697 5,353 4,993
NOTES: Table 7-4(R)
2015 Urban Water Management Plan
7-1
Chapter 7: Water Conservation & Demand Management Measures
7.1 HISTORY
Water conservation is an integral part of the City’s overall water management strategy and was first
referenced as a part of the water management policies in 1973. In 1985, the City adopted the Annual
Water Operational Plan policy that established water conservation as a means of extending water
supplies during projected water shortages. Many technological and philosophical changes have occurred
since that time, proving that water conservation can be used for both a short-term corrective measure, for
immediate water supply shortages, and as a long-term solution to water supply reliability.
The City’s long-term water conservation plan is embedded in California Urban Water Conservation
Council’s Memorandum of Understanding (MOU) regarding water conservation and the implementation of
the Best Management Practices (BMPs). In September 1991, the City Council approved the signing of the
MOU and has approved, through the City’s financial planning process, the implementation of the BMPs
since that time.
Table 31 lists the CUWCC’s BMPs and implementation status which are consistent with the Demand
Management Measure (DMM) provisions in the Urban Water Management Planning Act. As signatory to
the MOU and reporting member of the California Urban Water Conservation Council (CUWCC), the City
has submitted the necessary documentation to the CUWCC and has received certification stating the City
has met coverage requirements for the Foundational BMPs and gallons per capita consumption option
therefore meeting the compliance criteria in the Act and CWC 10631 (i) regarding the Demand
Management Measures. Brief summaries of the City’s Demand Management Measures have been
provided below to provide additional detail about the City’s water conservation program. The City’s
CUWCC coverage reports and other information regarding the status of the implementation of each
measure are detailed in Appendix VI.
7.2 WATER CONSERVATION PROGRAM HIGHLIGHTS
The Utilities Department’s Utilities Services section
implements the City’s core water conservation programs.
Examples of successful program activities are:
1. Enforcement of all water conservation related
municipal codes
2. Monthly site inspections of properties with
suspected leaks and inefficient uses of water
3. Enforcement of the toilet retrofit upon sale program
4. Facilitation of the Department’s school education
contract
5. Implementation of the Department’s public
outreach and communication programs
6. Monitoring of citywide per capita water demand
7. Water use surveys, audits and inspections
8. Implementation of conservation rebate and
giveaway programs
9. Management of the City’s recycled water program
Through the City’s water conservation programs and policies, potable water use has been reduced from
182 gpcd in 1987 to 92 gpcd in 2015, well below its SBX7-7 interim goal of 120 gpcd and its compliance
year goal of 117 gpcd. With the continuation of the demand management measures listed below, the City
anticipates continuous compliance with both the CUWCC’s MOU and all state conservation mandates in
2020 and well into the future.
2015 Urban Water Management Plan
7-2
TABLE 31. Water Demand Management Measures
Demand Management Measures and California Urban Water Conservation Council BMPs
CUWCC BMP Organization and Names (2009 MOU) UWMP DMMs Status
Type Category BMP
# BMP Name DMM # DMM Name Compliant
Foundational
Utility
Operations
Programs
1.1 Operations Practices i, vi
Water waste prevention
ordinances / Water
conservation program
coordination and
staffing support
Yes
1.2 Water Loss Control v
Programs to assess
and manage distribution
system real loss
Yes
1.3
Metering with
Commodity Rates for
All New Connections
and Retrofit of Existing
Connections
ii Metering Yes
1.4 Retail Conservation
Pricing iii Conservation pricing Yes
Education
Programs
2.1 Public Information
Programs iv Public education and
outreach Yes
2.2 School Education
Programs iv Public education and
outreach Yes
NOTES:
Source: City of San Luis Obispo Utilities Department, 2016.
7.3 WATER WASTE PREVENTION ORDINANCES
According to the DWR 2015 UWMP Guidebook, a water waste ordinance that explicitly states the waste
of water is to be prohibited must be adopted. In an effort to promote the responsible use of water and
minimize water waste, the City’s water waste prohibitions are included in Chapter 13.07 of the City’s
Municipal Code, which defines water waste as follow:
13.07.020 – Water runoff prohibited.
A. No person shall cause any water delivered by the city water system to flow away from property
owned, occupied or controlled by such person in any gutter, ditch or in any other manner over the
surface of the ground, so as to constitute water waste runoff.
B. “Water waste runoff” means water flowing away from property and which is caused by excessive
application(s) of water beyond reasonable or practical flow rates, water volumes or duration of
application. (Ord. 1089 § 1 (part), 1987)
In accordance with City Municipal Code 13.07.030, when deemed necessary in the judgment of the City
Council to conserve water during critical water periods, the City Council may also by resolution declare an
emergency condition and do any or all of the following which in its judgment is deemed advisable after
publication of notice thereof in a newspaper of general circulation distributed in the city or after
reasonable notice thereof is otherwise given by the city to users:
1. Limit irrigation within the City water service area to specified hours, or prohibit irrigation entirely
within the service area or any portion or portions thereof;
2. Limit all customers inside the City water service area to specified maximum usages of water for
each category of users;
2015 Urban Water Management Plan
7-3
3. Implement other water conservation measures as deemed appropriate.
7.4 METERING
In accordance with the 2015 UWMP guidebook and CWC 527 (a) (1), the City has metered all of its
services connections. Having all service connections metered encourages water conservation by
effectively billing customers for the quantity of water consumed, forming a relationship between water
consumed and total cost of the water bill.
Meter replacement programs exist for all customer classes in order to replace aged meters with newer
meters that register water more efficiently, ensuring that all water consumed by customers is billed for and
accounted for by the City to the extent feasible. Water meters are replaced based on age of meter and
also as defective or under-registering meter types are discovered. These replacements ensure that
accurate consumption data is delivered to both the customer and the utility.
7.5 CONSERVATION PRICING
According to the DWR 2015 UWMP Guidebook, retail water agencies need to describe the pricing
structure that is used by the water agency. Conservation pricing is designed to discourage wasteful water
habits and encourage conservation. CUWCC BMP 1.4 (Appendix VI) identifies a water rate structure that
is no more than 30 percent flat charge as encouraging and supporting conservation habits. As shown in
Appendix VI, the City’s water rate structure meets the requirements of the UWMP and CUWCC as a rate
that encourages conservation.
7.6 PUBLIC EDUCATION AND OUTREACH
The City has used public education and outreach as a mechanism for decreasing water use in the City
and for promoting water conservation since the 1970s. The City’s public outreach and education
programs currently include the following:
1. Quarterly Resource Newsletter
2. Social media use (Facebook, Twitter, Instagram)
3. Billing inserts
4. Streaming videos
5. Direct mail
6. High use mailers
7. Drought/conservation portal on City website
8. Funding for SLO Waterwise Landscaping website
9. Various newspaper articles
10. Monthly KCBX public radio drought updates
11. Booth at biannual SLO Home Show
12. Booth at yearly SLO Preparedness Expo
13. Booth at Thursday downtown Farmers Market (26 times a year)
14. Host of Community Water Forum
15. School education programs (K-12)
16. Annual meetings with local home owners associations
The City’s public education and outreach programs are continually adapting to ensure that the messaging
stays effective and relevant.
7.7 PROGRAMS TO ASSESS AND MANAGE DISTRIBUTION SYSTEM REAL LOSS
The City has been conducting annual AWWA water loss audits since 2009. Water loss statistics identified
from the AWWA water audits can be viewed in detail in Chapter 3 and Appendix IV.
2015 Urban Water Management Plan
7-4
In order to reduce water loss, the City conducts service line replacement projects based on service line
age and condition, along with extensive programs to replace defective polybutylene service lines that
have been identified to have a high likelihood of failure. Water meter replacement programs exist to
replace meters based on age, consequence of failure, and likelihood of failure. Along with these
maintenance programs, the City also implements a valve exercising program that ensures water mains
can be isolated during repairs to minimize the amount of water lost during water main breaks and repairs.
During 2014 and 2015 the City finished a water master plan which identifies and prioritizes future
maintenance and capital improvement projects which will reduce future water loss due to infrastructure
failure.
7.8 WATER CONSERVATION PROGRAM COORDINATION AND STAFFING SUPPORT
The Utilities Services section of the Utilities Department manages and implements water conservation
programs for the City. This section consists of a manager who coordinates the conservation programs,
three full time Utilities Services Technicians, and temporary staffing as needed. Many support services
such as the school education program and elements of the public outreach program are provided by
contract to ensure the City meets its conservation goals and promotes responsible water use.
7.9 OTHER DEMAND MANAGEMENT MEASURES
For over five years the City has implemented cost-effective programs that will increase water efficiency
citywide. The City has voluntarily implemented the following DMMs and plans to continue implementing all
DMMs and BMPs into the future. The following is a description of these additional programs.
Water Audits
The Utilities Department’s Utilities Services section offers free indoor and outdoor water audits to
customers who have high water use or would like to reduce their water consumption. These audits
provide information about irrigation reduction methods, proper toilet maintenance, low flow fixtures
installation, and general information on methods for reducing water use. This service is often offered
proactively to customers who have unexplained high use, water waste violations, or other instances
where audits could provide potential water savings. Customers can request a free water audit on the
City’s website.
Rebate Programs
In response to the Governor’s Emergency Drought Declaration, the City Council authorized $100,000 in
support of effective rebate programs in June 2015. $100 dollar rebates were provided for qualified toilet
and washing machine replacements. Going forward, staff will be examining the expansion of these rebate
programs to include other types water demand reductions.
Retrofit Upon Sale Program
The City’s Retrofit Upon Sale Program requires the replacement of high flow toilets when a home has a
change of ownership or major remodel. This program has existed since the early 1990’s and along with
several other toilet replacement programs, has reduced the City’s long term water demand by an
estimated 1,500 acre-feet per year. All properties that have been certified to have low flow toilets are
shown via a user-friendly online mapping tool at slowater.org. This tool also provides the City with a
database that can be used to help project the effectiveness of future toilet rebate, offset, and replacement
programs.
2015 Urban Water Management Plan
8-1
Whale Rock Reservoir.
Chapter 8: Water Shortage Contingency Plan
Developing and maintaining a multi-source water supply portfolio to increase resiliency against water
shortages has been a City priority for many years. A water shortage occurs when water supplies are
insufficient to support demand. A water shortage could occur due to drought, earthquake, infrastructure
failure, or other emergency. Droughts occur with unpredictable frequency, intensity, and duration. The
Department of W ater Resources defines drought as “A deficiency of precipitation over an extended period
of time resulting in a water shortage for some activity, group, or environmental sector.”
This Water Shortage Contingency Plan (WSCP) provides the foundation for a staged response to
worsening water shortage conditions. A draft Water Conservation Ordinance, to update Chapter 13.07 of
the City’s Municipal Code, is proposed to establish the regulations and procedures for implementing this
Plan. The draft Water Conservation Ordinance is provided in Appendix VI.
8.1 WATER SHORTAGE DETERMINATION
The degree of the water supply shortage determines the necessary level of response from the City and
customers. When determining a water shortage stage the City evaluates the following:
• Water demand across customer categories
• Water availability at each supply source
• Available water supply options including supplemental water supplies
The City utilizes a water projection model, testing both hypothetical and actual water demand scenarios,
to analyze current water storage at each reservoir and to predict how long the water supplies are
available. The model accounts for the total storage in the three reservoirs, in conjunction with other
available resources, needed to meet the City’s
water demand. The model uses historical hydrologic
information based on the average for the worst
drought period (2012 to 2014). Other data included
in the model are:
• Water Entitlement (contractual or
percentage)
• Current reservoir level
• Gallons per capita per day water demand
• Rainfall
• Temperature
• Evaporation
• Existing population
• Future population growth
Utilizing a water projection model as part of its
water supply management enables the City to
foresee whether a water supply shortage is
anticipated in any given year, and the severity of a
shortage based on the availability of the City’s
different sources of supply and water demand
trends. The City uses the model to study the
potential impacts of climate change using increased
temperature and evaporation rates, along with
decreased precipitation.
2015 Urban Water Management Plan
8-2
8.2 WATER SHORTAGE RESPONSE
A water shortage response relies on the City’s ability to temporarily augment supply and/or reduce water
demand. The City’s water shortage response would combine a variety of elements from outreach to
enforcement, each increasing in intensity as the shortage persists. The City’s demand reduction targets
focus on water use limits and prohibitions that will reduce non-essential use, such as imposition of
restrictions on outdoor irrigation. Implementation of these restrictions is necessary to conserve the City’s
water supply for the greatest public benefit regarding domestic use, sanitation and fire protection. This
section reviews the general strategies the City will employ to mitigate the impacts of water shortage on
the community.
Voluntary Reduction Measures
All customers may be asked to voluntarily reduce their water usage during a water shortage. The City
may provide water conservation tips and suggestions through various public outreach methods,
encourage and distribute conservation devices such as low flow shower heads and faucet aerators,
discourage excessive outdoor watering, and encourage landscaping with drought tolerant plants.
Voluntary reductions measures are described in more detail in Section 8.3
Mandatory Reduction Measures
The City may place mandatory reduction measures on certain uses, such as restricting outdoor watering
to prescribed times and number of days per week beginning in the Watch Stage, with days and times for
landscape watering further limited in later stages. Mandatory reduction measures may limit specific
methods of irrigation (i.e., sprinkler ban).
The seasonal increase in water demand underscores the importance of implementing outdoor landscape‐
focused reduction programs. An average of approximately 50 percent of residential water use in San Luis
Obispo is for landscape irrigation. Therefore, restrictions on outdoor water use are generally highly
effective in reducing water demand. Outdoor uses are typically considered to be discretionary or
nonessential for health and safety purposes, are highly visible and relatively easy to monitor, and often
are a substantial component of water demand, particularly during the summer months when drought
conditions are often most severe.
Prohibitions
Prohibitions will vary by drought stage, with the fundamental purpose of prohibiting non‐essential uses not
required for basic health and safety. During a declared water shortage, specific prohibitions would be
described in a Water Shortage Ordinance adopted by the City Council. In the Critical Stage, all non‐
essential outdoor water use, except recycled water or grey water, may be prohibited.
The City will adopt regulations at the appropriate water shortage stage that require customers to take
certain measures to promote water conservation, such as posting signage at various establishments,
undergoing a water audit to maximize or demonstrate water conservation, and prescribing to customer‐
specific water budgets.
Supplemental Water Supply Options
During a water shortage emergency, the City may also utilize supplemental water supply options, or
acquiring a new supply as warranted by the current situation. Currently, this might include requesting all
5,482 afy of the City’s Nacimiento Reservoir allocation. In the future, this may include utilizing more
groundwater and/or utilizing highly treated wastewater in a potable reuse system. These water supply
options may be less desirable during normal operations due to increased operation costs.
8.3 WATER SHORTAGE STAGES
The goals of the City’s Water Shortage Contingency Plan are to extend the City’s available water
resources long enough to gain another winter rainfall period which could serve to add to reservoir
storage. Extending available water resources through water demand reduction provides time for the City
to bring on supplemental water supplies to meet demand. It is the City’s goal to implement water demand
reduction programs that will achieve measurable water savings without affecting customers’ lifestyles. In
the higher water shortage stages lifestyle and habit changes will be necessary.
2015 Urban Water Management Plan
8-3
This section identifies the measures that may be taken at each stage to achieve desired water use
reduction levels. The purpose of establishing water shortage stages is to clearly define the severity of the
shortage and establish appropriate targets for demand reductions. Defining these stages allows the City
to respond to worsening conditions, with each stage “triggering” different actions. The multi‐stage
approach provides different levels of response for a water shortage event ranging from a ten percent
supply deficiency up to a 50 percent or greater deficiency.
Table 32 provides a quick reference guide to the City’s Water Shortage Contingency Plan, though City
Council may adopt variations of these stages, independent from the stage resulting from the use of the
Water Projection Model, to strategically address the current water shortage situation. Each stage
describes increasing levels of water demand reduction and water supply augmentation methods. As
stated previously, during an actual water shortage emergency, other measures may be imposed.
Water Shortage Response Stage: MONITOR
San Luis Obispo has made water conservation an integral part of the community’s culture and policy
context for managing its water resources. The community has demonstrated a high commitment to
reducing its water usage during water shortages. Although not a true declaration of a water shortage, the
Water Shortage Contingency Plan’s Monitor Stage remains in place at all times along with voluntary
conservation and implementation of the California Urban Water Conservation Council’s Best
Management Practices. A complete description of the City’s water conservation program is included in
Chapter 7.
This stage is focused on achieving voluntary compliance, as opposed to a mandatory demand reduction
programs. To ensure the City is using water responsibly and remains in compliance with the SB X7-7
requirement to not exceed 117 gpcd, the City continually assesses available water supply levels, monitors
customer water demand trends, conducts water loss audits, and evaluates potential supplemental
supplies. The following are examples of measures that may be taken to facilitate water conservation
consistent with CUWCC best management practices:
• Implement public outreach and communication programs (bill stuffers, social media, etc.)
• Participate in trade shows, home shows, and special community events
• Identify largest water users in each sector and offer complementary water audits
• Identify and notify customers of possible leaks and inefficient uses of water
• Encourage the use of drip irrigation and drought tolerant plants
• Implement school (K-12) education programs related to water conservation
• Enforce the toilet retrofit upon sale program
•
Actions at the Monitor Stage would also include active enforcement of the City’s water waste prohibitions,
such as those adopted by the Governor in 2016, from Chapter 13.07 of the City’s Municipal Code, which
defines water waste as follow (See also Table 32):
13.07.020 – Water runoff prohibited.
A. No person shall cause any water delivered by the city water system to flow away from property owned,
occupied or controlled by such person in any gutter, ditch or in any other manner over the surface of the
ground, so as to constitute water waste runoff.
B. “Water waste runoff” means water flowing away from property and which is caused by excessive
application(s) of water beyond reasonable or practical flow rates, water volumes or duration of application.
(Ord. 1089 § 1 (part), 1987)
2015 Urban Water Management Plan
8-4
TABLE 32: Water Shortage Response Stages
Quick Reference Guide
STAGE WATER SUPPLY
STATUS1 CITY ACTIONS
PER CAPITA
GOAL
(GPCD)
Monitor
5+ years of
available water
supply
City maintains conservation messaging at levels that
ensure compliance with SB X7-7 maximum of 117 gpcd. 1172
Watch
< 5 years of
available water
supply
City increases conservation messaging. City examines
available alternative water sources (groundwater,
Nacimiento full allocation, etc.) and takes action based
on current circumstances to meet demand. City may
implement mandatory conservation measures to meet
per capita reduction target.
107
Warning
< 4 years of
available water
supply
City implements mandatory conservation measures
including outdoor irrigation restrictions (examples: 3 or 2
days a week watering and only serving water upon
request at restaurants) and consider a Water Offset
Program for new connections.
95
Severe
< 3 years of
available water
supply
City implements Water Allotment Program. Water Offset
Program for new connections may be increased.
Additional outdoor irrigation restrictions may be added
(such as no spray irrigation).
90
Extreme
< 2 years of
available water
supply
City continues to implement a Water Allotment Program
with reduced levels. Water Offset Program for new
connections may be increased. Outdoor irrigation may be
prohibited for all uses. Cessation of all new connections
may be considered.
85
Critical
< 1 year of
available water
supply
City continues to implement a Water Allotment Program
at further reduced levels (minimum for public health and
safety). Outdoor irrigation prohibited for all uses. Water
Offset Program to cease and no new connections
permitted.
75
NOTES:
1. The City’s Water Supply Status is informed by the Water Projection Model and per Section 8.2 of Chapter 8.
2. The City’s per capita goal of 117 gpcd is the City’s SB X7-7 2020 Target, see Chapter 3.
3. Recycled water is not subject to demand reduction programs, water allocations or other drought response
programs. The City’s recycled water program is described in further detail in Chapter 5.
2015 Urban Water Management Plan
8-5
Water Shortage Response Stage: WATCH
When the City’s available water supply would provide less than five years of water, a recommendation
would be made to the City Council that a water shortage be declared. The City Council would be asked to
adopt a resolution declaring the City enter the Watch Stage and urge the public to reduce water use by
approximately 8.5 percent from 117 gpcd to 107 gpcd.
During the “Watch” Stage, the demand management measures utilized during the Monitor Stage above
will increase along with a continued focus on voluntary compliance. The City will also increase public
outreach, implement system and operational changes, increase enforcement actions, and undertake
other administrative actions. These program expansions and changes may include:
Water Demand Reduction Programs:
• Accelerate water audit programs for all customer classes
• Identify largest water users in each sector and contact for complementary water audits
• Increase water waste patrols
• Conduct water use surveys
• Implement rebate programs
• Consider the use of irrigation limitations
Public Outreach Programs:
• Issue a press release following Watch Stage declaration
• Include information in quarterly Resource Newsletter
• Update City website and create a page dedicated to information on details of WSCP Watch Stage
• Consider use of billing inserts to notify public of current situation and needs
• Coordinate with regional partners on messaging and outreach
• Develop outreach program for City staff to promote consistent messaging related to water supply
and water conservation
• Increase outreach at public events such as Farmers Market, SLO Home Show, and home owners
association board meetings
• Focus social media platforms on issues consistent with needed demand reductions
System and Operational Changes:
• Reduce water usage for main flushing and hydrant flushing
• Reduce distribution system pressure where feasible
• Increase leak detection, water meter testing, and water meter replacement
• Decrease allowable time for repairing leaks in distribution system
• Require use of non-potable water sources for all street sweeping and hydrocleaning
• Activate the Drought Taskforce
Enforcement Actions:
• Actively enforce water waste prohibitions
• Update online forms for reporting water waste and move forms to front page of website
• Continue to follow City’s policy for code violations and issue Notices of Violation and
Administrative Citations where deemed necessary
Other Administrative Actions:
• Begin drafting ordinance revisions and code changes that would go into effect in subsequent
water shortage stages
• Plan for the funding and implementation of specific conservation programs launched in
subsequent water shortage stages
2015 Urban Water Management Plan
8-6
• Review potential fiscal impacts of drought (i.e., increased water supply, operational, and capital
costs); and demand reductions (reduced revenue)
• Prepare for implementation of next water shortage stage
• Identify and plan for the need for additional staff. In planning for additional staff, consideration
should be given to funding, available office space, vehicles, training, and other needed supplies
and support
• Consider need for drought surcharge to stabilize revenue
• Consider deferring previously scheduled capital projects as necessary to invest in acquisition of
needed water supply sources and demand reductions
• Review available supplemental water supply options, such as increased use of groundwater,
utilization of potable reuse, and implementation of a recycled water filling station
Water Shortage Response Stage: WARNING
When the City’s available water supply would provide less than four years of water, a recommendation
would be made to the City Council to move to the next water shortage stage. The City Council could be
asked to adopt a resolution declaring the City enter the Warning Stage and urge the public to reduce
water use by an additional approximately 11 percent from 107 gpcd to 95 gpcd including mandatory
conservation measures.
The water conservation measures described in the Monitor and Watch Stages above may increase during
the Warning Stage, with an increased focus on limiting outdoor water uses. System and operational
changes would remain in place. These increases and additions to programs may include:
Water Demand Reduction Programs:
• Continue implementation of and possible increase of all demand reduction programs listed in
Watch Stage
• Limit outdoor watering to two or three days a week and only between the hours of 7:00 p.m. and
7:00 a.m.
• Defer landscape installations for new development or require development to install landscaping
that provides a significant reduction in water demand ( e.g. a minimum of 50%) as compared to a
conventional drought tolerant landscaping during normal water years
• Require hotels/motels/inns to offer the option to opt out of laundry services
• Require restaurants to only serve water upon request
• Restrict use of decorative water features and fountains
• No watering within 48 hours of measureable rainfall
• No washing down of sidewalks, driveways, parking lots or other hardscape areas unless
necessary to protect public health and safety
• No exterior washing of buildings, dwelling and other structures, except for pre-approved uses
• No vehicles washing except at commercial car washing facilities or by use of a bucket and/or
hose equipped with a shut off nozzle
Public Outreach Programs:
• Continue implementation of and possible increase of all public outreach programs listed in Watch
Stage
• Issue a press release following Warning Stage declaration
• Target outreach to customers with large landscapes regarding irrigation restrictions
• Use of billing inserts, postcards, and direct mail pieces to inform customers of new requirements
and prohibitions
• Coordinate with local business groups such as the Chamber of Commerce and landscaping
associations to help encourage conservation among commercial customers
2015 Urban Water Management Plan
8-7
• Coordinate with home owners associations, property rental agencies, and other local groups to
help encourage conservation among residential customers
Increased Enforcement Actions:
• First Violation: Customer notification and education
Customer will be notified by staff of the particular violation observed, and the demand reduction
programs currently in place. The customer will be provided with needed resources to help them
comply with requirements. Examples of notification include: door tags containing violation
information, mailed letter, and/or personal phone call by staff
• Second Violation: Issuance of Notice of Violation
Customer will be issued a written notice of violation (NOV), notifying the customer of specific
violation, date and time the violation was observed, and consequences of subsequent violations
• Subsequent Violations: Customer may be issued a penalty/fine for violation
Other Administrative Actions:
• Continue implementation of and possible increase of all
other administrative actions listed in Watch Stage
• Prepare utility billing system and bill format for water
allocations and reductions listed in subsequent stages.
• Establish appeals committee for customers who
exceed allotments in subsequent stages or receive
fines from violating water waste prohibitions
• Increase utility billing training and support to address
additional requirements of Warning Stage and future
stages
• Begin preparing for Severe Stage
Implementation of a Water Demand Offset Program:
During the Warning Stage, the City may consider implementing
a water demand offset program. Water demand offset
programs are designed to require new development that
causes increased water demand to offset such demand through
conservation or acquisition/development of new supplies. The
goal of an offset program is to ensure that a new development
does not increase current and future water demands.
At the Warning stage the City may choose to implement a neutral offset program, requiring that new
demands offset usage at a rate of 1:1. Future stages of the WSCP may suggest a more aggressive, “net
positive” water demand offset program. A “net positive” water demand offset program would require a
positive offset of a project’s water demand. An example of this would be a project required to offset its
water demand at a ratio higher than 1:1, such as 1.5:1 or 2:1.
There are several types of offset programs in use across California and the United States. Examples of
potential offset programs are listed below.
• Toilet replacements
• Smart irrigation controllers
• Onsite reuse systems
• Submetering
• In-lieu fee
• Irrigation system retrofits
• Waterless urinals
• Rainwater capture
2015 Urban Water Management Plan
8-8
Water Shortage Response Stage: SEVERE
When the City’s available water supply would provide less than three years of water, a recommendation
would be made to the City Council to move to the next water shortage stage. The City Council would be
asked to adopt a resolution declaring the City enter the Severe Stage and urge the public to reduce water
use by an additional approximately five percent from 95 gpcd to 90 gpcd.
At this water shortage response stage, the City would continue implementation of demand reduction,
public outreach, and enforcement programs described in prior stages. System and operational changes
would remain in place. At the Severe Stage, a water offset program may increase to a “net positive”
program, such as 1.5:1 or 2:1 and the City may implement a water allotment program. The following
allotment method may be used:
Customer Classification Severe Stage Allotment
Single Family Residential and
Multi-family Residential
A per capita allotment of 64 gppd,
verification of persons per household
may be requested
Commercial and Institutional
Baseline allocation or allocation
based on percent reduction from
normal usage
Landscape Meters Allocation based on percent
reduction from normal usage
Excessive water use penalties may be imposed as outlined in the City’s Municipal Code.
Water Shortage Response Stage: EXTREME
When the City’s available water supply would provide less than two years of water, a recommendation
would be made to the City Council to move to the next water shortage stage. The City Council would be
asked to adopt a resolution declaring the City enter the Extreme Stage and urge the public to reduce
water use by an additional approximately five percent from 90 gpcd to 85 gpcd.
At this water shortage response stage, the City would continue implementation of demand reduction,
public outreach, and enforcement programs described in prior stages. System and operational changes
would remain in place. At the Extreme Stage, a “net positive” water offset program may continue to be
offered and outdoor irrigation may be prohibited. The following allotment method may be used:
Customer Classification Extreme Stage Allotment
Single Family Residential and
Multi-family Residential
A per capita allotment of 56 gppd,
verification of persons per household
may be requested
Commercial and Institutional
Baseline allocation or allocation
based on percent reduction from
normal usage
Excessive water use penalties may continue to be imposed as outlined in the City’s Municipal Code.
At this stage, due to the limited water supplies that remain, the City could consider the cessation of new
connections to the water distribution system.
2015 Urban Water Management Plan
8-9
Water Shortage Response Stage: CRITICAL
When the City’s available water supply would provide less than one year of water, a recommendation
would be made to the City Council to move to the next water shortage stage. The City Council would be
asked to adopt a resolution declaring the City enter the Critical Stage and urge the public to reduce water
use by an additional approximately 12 percent from 85 gpcd to 75 gpcd.
At this water shortage response stage, the City would continue implementation of demand reduction,
public outreach, and enforcement programs described in prior stages. System and operational changes
would remain in place. At the Critical Stage, a water offset program may no longer be offered and outdoor
irrigation may continue to be prohibited. The following allotment method may be used:
Customer Classification Critical Stage Allotment
Single Family Residential and
Multi-family Residential
A per capita allotment of 48 gppd,
verification of persons per household
may be requested
Commercial and Institutional
Baseline allocation or allocation
based on percent reduction from
normal usage
Excessive water use penalties may continue to be imposed as outlined in the City’s Municipal Code.
At this stage, due to the limited water supplies that remain, the City would consider the cessation of new
connections to the water distribution system.
8.4 REVENUE AND EXPENDITURE IMPACTS
During a water shortage, revenues from water sales can be reduced but the City’s operations and
maintenance costs would not reduce accordingly. In fact, during the these periods, the City’s operations
budgets can increase due to the implementation of water demand reduction measures, public outreach,
enforcement, groundwater exploration, water quality concerns, and other actions taken by the City during
the crisis. The reduction in revenues resulting from decreased water use may result in the need to raise
water rates during that period.
Under the City’s water rate structure, bills are based mainly on customer usage choices and resulting
demand on the water systems. Water Fund revenue is collected from multiple sources, but approximately
90 percent of revenue is directly tied to water service charges including the base fee.
To minimize the need to raise rates during water shortages, the City has a policy that requires a minimum
reserve of twenty percent of the Water Fund’s operating budget. While this is a minimum amount, the
reserve amount is typically above this minimum policy level.
City staff provides ongoing tracking of revenues and evaluates the potential impacts associated with
changes in water demand assumptions used in the Annual Water Fund Analysis. The City Council
considers the water rates necessary to provide water service to the community on an annual basis and
approves water rate changes as needed.
As part of the 2015-17 Financial Plan, the City included a base fee and tiered drought surcharge as water
demand was projected to reduce by 12 percent as a result of State water use reduction mandates. The
surcharge was proposed to offset the loss in revenue associated with the State order as the City was still
responsible for the costs of the City’s multi-source water supply and debt payments. In addition to water
supply, Water Fund revenue supports ongoing maintenance and operating programs needed to ensure
2015 Urban Water Management Plan
8-10
that the water treatment and delivery systems meet all federal and state water treatment regulations and
are operated and maintained to provide safe and reliable service.
8.5 CATASTROPHIC WATER SUPPLY INTERRUPTION
The City has an Emergency Response Plan to cover a variety of potential disasters including:
earthquakes, floods, wildland fires, etc. The Plan identifies resources available to the City from other
agencies or private companies in the area. Additionally, the City of Morro Bay and the Whale Rock
Commission (of which the City of San Luis Obispo is a member) executed an agreement in June of 2000
which provides for Mutual Aid between the agencies during disruption of water deliveries or lack of
available water supplies. The agreement provides a general framework for exchanging water between
agencies in the event of emergencies or other water disruptions. The agreement is voluntary based on
each agency’s ability to assist at any point in the future.
In relation to providing water service, the City would utilize portable generators to minimize water
disruptions during an extended power outage. These generators are maintained and available to the City
at any time and are stored at the City Corporation Yard.
The City is a member of the Water Agency Response Network (WARN). WARN is a statewide
organization of water agencies and companies that have entered into a mutual aid agreement to assist
other water agencies during emergencies or other water related situations. The agreement provides the
frame work for providing assistance and provides a key contact to initiate a multiple agency response to a
water emergency situation.
8.6 MINIMUM SUPPLY NEXT THREE YEARS
Consistent with section 6.6, Water Supply Reliability Analysis, in Chapter 6, the City’s multiple dry year
scenario was determined to be 2012 to 2014 as the combined rainfall total for those three years was the
lowest on record. Available water supplies during this period assume the City’s safe annual yield from
Salinas and Whale Rock Reservoirs, contractual supply from Nacimiento Reservoir, and recycled water
supply are available totaling 12,622 acre feet of available supply, as shown in Table 33.
As directed by DWR, this section was prepared based on what is known by the City at the time the
UWMP was prepared. After the current drought has a “bookend” the safe annual yield of Salinas and
Whale Rock reservoirs will be recalculated. Related changes to safe annual yield will be incorporated into
planning scenarios.
TABLE 33: Minimum Supply Next Three Years
2016 2017 2018
Available Water
Supply 12,622 12,622 12,622
NOTES:
1. Department of Water Resources, Table 8-4.
2. Units are in acre-feet per year.
3. Volume available includes the City’s contractual supply to Nacimiento Reservoir,
Safe Annual Yield from Salinas and Whale Rock Reservoirs, and recycled water.
Source: City of San Luis Obispo Utilities Department, 2016.
2015 Urban Water Management Plan
8-11
8.7 REQUIRED UWMP STANDARDIZED TABLES:
Stages of Water Shortage Contingency Plan
Stage
Complete Both
Percent
Supply
Reduction1
Water Supply Condition
Monitor 0
City maintains conservation messaging at levels
that ensure compliance with maximum 117 gallons
per capita per day (gpcd).
Watch 10
City increases conservation messaging. City
examines available alternative water sources
(groundwater, Nacimiento full allocation, etc.) and
takes action based on current circumstances to
meet demand. City may implement mandatory
conservation measures to meet per capita
reduction target.
Warning 20
City implements mandatory conservation
measures including outdoor irrigation restrictions
(examples: 3 or 2 days a week watering and only
serving water upon request at restaurants) and
consider a Water Offset Program for new
connections.
Severe 30
City implements Water Allotment Program. Water
Offset Program for new connections may be
increased. Additional outdoor irrigation restrictions
may be added (such as no spray irrigation).
Extreme 40
City continues to implement a Water Allotment
Program with reduced levels. Water Offset
Program for new connections may be increased.
Outdoor irrigation may be prohibited for all uses.
Cessation of all new connections may be
considered.
Critical 50
City continues to implement a Water Allotment
Program at further reduced levels (minimum for
public health and safety). Outdoor irrigation
prohibited for all uses. Water Offset Program to
cease and no new connections permitted.
1 One stage in the Water Shortage Contingency Plan must address a water shortage of 50%.
NOTES: Table 8-1 R.
2015 Urban Water Management Plan
8-12
Restrictions and Prohibitions on End Uses
Stage Restrictions and Prohibitions on End Users
Penalty, Charge, or
Other
Enforcement?
Monitor Landscape - Restrict or prohibit runoff from landscape
irrigation Yes
Monitor Other - Customers must repair leaks, breaks, and malfunctions
in a timely manner Yes
Monitor Other - Prohibit use of potable water for construction and
dust control Yes
Watch Other - Require automatic shut of hoses Yes
Warning Landscape - Limit landscape irrigation to specific times Yes
Warning Landscape - Limit landscape irrigation to specific days Yes
Warning Water Features - Restrict water use for decorative water
features, such as fountains Yes
Warning CII - Lodging establishment must offer opt out of linen service Yes
Warning CII - Restaurants may only serve water upon request Yes
Warning Water Features - Restrict water use for decorative water
features, such as fountains Yes
Critical Landscape - Other landscape restriction or prohibition Yes
NOTES: Table 8-2 (R).
2015 Urban Water Management Plan
8-13
Stages of Water Shortage Contingency Plan - Consumption Reduction Methods
Stage Consumption Reduction Methods by Water Supplier
All Expand Public Information Campaign
Watch Offer Water Use Surveys
Watch Provide Rebates on Plumbing Fixtures and Devices
Watch Provide Rebates for Landscape Irrigation Efficiency
Watch Decrease Line Flushing
NOTES: Table 8-3 R.
Minimum Supply Next Three Years
2016 2017 2018
Available Water
Supply 12,622 12,622 12,622
NOTES: Table 8-4 R.