HomeMy WebLinkAbout11-19-2013 c9 water resources status report
FROM: Carrie Mattingly, Utilities Director
Prepared By: Wade Horton, Water Division Manager
SUBJECT: 2013 Water Resources Status Report
RECOMMENDATION
Receive and file the 2013 Water Resources Status Report.
DISCUSSION
Background
Annual reports relative to the City’s water resources have been provided to the City Council
since 1985. The 2013 Water Resources Status Report, summarizing calendar year 2012 data,
provides an overview and update of the City’s water resources. The attached report discusses
four major topics:
I. Existing Water Supply Status
II. Multi-Source Water Supply
III. Water Demand Management
IV. Projected Water Supply Situation
2013 Water Resources Status Report Summary
Due to investment in a multi-source water supply, the City has achieved a diversified water
portfolio sufficient to meet current and future water needs. Although San Luis Obispo County is
now facing a D3 Extreme drought as characterized by the National Oceanic and Atmospheric
Administration, the City’s five water sources (Salinas and Whale Rock Reservoirs, Nacimiento
Pipeline Project, groundwater, and recycled water) provided ample water to meet 2012 customer
demand. In the event of an extreme prolonged drought period, as of September 2013, the City
has approximately eight years of water supply until reservoirs levels are drawn down to
“minimum pool” in Salinas and Whale Rock reservoirs (minimum pool is the minimum amount
of water required to support aquatic habitat).
While the current water supply situation is favorable, the City will continue to incrementally
expand the use of recycled water and continue its water conservation efforts to comply with State
regulations and ensure long-term efficient use of water resources. The 2013 Water Resources
Status Report summarizes the City’s water supply status and its ongoing water conservation
program efforts.
Multi-Source Water Supply Status
For over 20 years, a major Council goal was the pursuit of additional long-term water supplies to
meet the current and future community water demand. With the recycled water program,
Meeting Date: 11-19-2013
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2013 Water Resources Status Report Page 2
ongoing water conservation efforts, and the Nacimiento Pipeline Project the City has attained
this goal, a significant accomplishment ensuring reliable water supplies for the community well
into the future. As of September 2013, the City’s two water supply reservoirs (Salinas and Whale
Rock) were at 45 percent and 61 percent of total storage capacity respectively. The Nacimiento
Pipeline Project began water deliveries to the City in January of 2011. The City has contractual
rights for 3,380 acre feet per year from the Nacimiento Reservoir.
Additional users continue to be added to the City’s recycled water system. Recycled water use
for calendar year 2012 totaled approximately 165 acre feet, up four percent from 158 acre feet in
2011. During 2012, two new sites were connected to the City’s recycled water distribution
system to provide landscape irrigation.
City Water Usage
The City’s total water use in calendar year 2012 was 5,541 acre-feet compared to 5,285 acre feet
in calendar year 2011. The City’s per capita water use increased compared to the 10-year low
experienced in 2011 (see Table 1).
The per capita use rate is not the amount that the average person uses but takes into account all
water uses including residential, commercial, industrial, and landscape. In 2012 the water use
rate increased from 104 to 109 gallons per capita per day (gpcd) compared to 2011.
Table 1: Population Estimates, Water Use & Rainfall
Year Population Total Water Use
(acre feet)
Per Capita
(gpcd)
Rainfall1
(inches)
2003 44,357 5,968 120 16.4
2004 44,298 6,239 126 21.0
2005 44,687 6,098 122 20.8
2006 44,559 5,999 120 17.2
2007 44,433 6,493 130 12.7
2008 44,579 6,359 127 18.1
2009 44,829 6,134 122 18.9
2010 44,948 5,489 109 36.0
2011 45,418 5,285 104 18.9
2012 45,308 5,541 109 21.5
Ten-year per capita average 119
NOTE: 1. Rainfall amounts for calendar year source: Cal Poly CIMIS Weather Station
Based on the policies adopted in the City’s Water and Wastewater Management Element
(WWME), Table 2 summarizes the available water supplies to serve the community’s water
demands.
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2013 Water Resources Status Report Page 3
Table 2: 2012 Water Resource Availability
Water Resource Acre Feet Description
Salinas & Whale Rock Reservoirs 6,940 Safe Annual Yield
Nacimiento Reservoir 3,380 Dependable Yield
Recycled Water 165 2012 Annual Usage
Siltation from 2010 to 2060 (500) WWME Policy A 4.2.2
9,985 2012 Annual Availability
Water Supply Accounting and Demand
WWME policy specifies that the City will account for water supplies necessary to meet three
specific community needs: 1) Primary Water Supply, 2) Reliability Reserve, and 3) Secondary
Water Supply, which are discussed in detail in the 2013 Water Resources Status Report
(Attachment 1) and summarized in Table 3 below.
Table 3: 2012 Water Supply Accounting
Total
Acre Feet
Primary Water
Supply
Reliability Reserve Secondary Water
Supply
9,985 7,152 1,207 1,626
Water Demand Management
The City’s water conservation program continues to implement the California Urban Water
Conservation Council’s Best Management Practices as defined in its Memorandum of
Understanding Regarding Urban Water Conservation in California. The water conservation
program will continue to play an important role in the future as the City faces new water supply
challenges attributable to climate change and regulatory requirements related to statewide water
use reduction goals.
Projected Water Supply Situation
The City utilizes a computer model to project how long the City's available water supplies will
last based on a number of assumptions. The model uses historical drought weather patterns,
projected water demands, and other factors to forecast the City's water supply position and to
make water policy recommendations. Assuming ongoing drought conditions, the model
estimates current water supplies will last eight years.
Summary
The City of San Luis Obispo has achieved its goal of obtaining additional water resources to
meet the City’s current and future water demands. The City has demonstrated leadership in the
implementation of water conservation strategies since the late 1980s and the community has
embraced the importance of using its water resources wisely. With the Council’s support for the
use of recycled water and the completion of the Nacimiento Project, the City is well positioned
to meet current and future community water needs. The Council has accomplished the “multi-
source” water supply policy as identified in the Water and Wastewater Management Element of
the General Plan and has also successfully established a reliability reserve which will serve the
City well in the event of a water supply contingency.
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2013 Water Resources Status Report Page 4
FISCAL IMPACT
No fiscal impact is associated with the recommended action.
ATTACHMENTS
1. 2013 Water Resources Status Report
..\Water Resources Status Report (Mattingly-Horton)
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City of San Luis Obispo
2013 Water Resources
Status Report
Prepared by:
Ron Munds, Utilities Conservation Manager
Jennifer Metz, Utilities Project Manager
Wade Horton, Deputy Director-Water
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City of San Luis Obispo
2013 Water Resources Status Report
TABLE OF CONTENTS
I. EXISTING WATER SUPPLY STATUS ................................... 1
Current Supply Status ...................................................................... 1
2012 Summary ................................................................................... 2
II. MULTI‐SOURCE WATER SUPPLY .................................... 4
Water Supply Sources ..................................................................... 4
Salinas & Whale Rock Reservoirs................................................ 4
Nacimiento Reservoir ...................................................................... 4
Recycled Water .................................................................................. 5
Groundwater ....................................................................................... 5
Water Resource Availability.......................................................... 5
Water Supply Accounting .............................................................. 5
III. WATER DEMAND MANAGEMENT ................................. 7
IV. PROJECTED WATER SUPPLY SITUATION ........................ 9
Reservoir Storage Curve ................................................................. 9
V.SUMMARY ................................................................... 10
LIST OF TABLES
Table 1: 2012 City Water Demand Sources .......................... 2
Table 2: Population Estimates, Water Use & Rainfall ........... 3
Table 3: 2012 Water Resource Availability ........................... 5
Table 4: 2012 Water Supply Accounting ............................... 7
Table 5: 2015 and 2020 Targets ............................................ 8
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City of San Luis Obispo
2013 Water Resources Status Report
The 2013 Water Resources Status Report updates the City Council and community members on water
supply accounting and demand projections as specified in the Water and Wastewater Management
Element of the General Plan, Policy A 5.3.1.
The 2013 Report covers four main areas:
I. Existing Water Supply Status
II. Multi‐Source Water Supply
III. Water Demand Management
IV. Projected Water Supply
I. EXISTING WATER SUPPLY STATUS
The City currently utilizes five water sources to
meet community water demand:
1. Salinas Reservoir (also referred to as Santa
Margarita Lake)
2. Whale Rock Reservoir
3. Nacimiento Reservoir
4. Recycled water from the City’s Water
Reclamation Facility
5. Groundwater
Current Supply Status
As of September 1, 2013, the City’s available water storage in Salinas Reservoir was 11,148 acre feet.
The City’s share of available Whale Rock storage was 11,935 acre feet. The combined total water
storage available to meet City water needs from these two sources was 23,083 acre feet, equating to
53 percent of maximum available storage.
San Luis Obispo County is currently experiencing a D3 Extreme Drought as characterized by the
National Oceanic and Atmospheric Administration. Fortunately, based on available storage from
Salinas & Whale Rock reservoirs, contractual water from Nacimiento Reservoir, estimated groundwater
production, estimated recycled water deliveries, and assuming the continuation of an extended
drought, the City has approximately eight years of water supply until reservoirs levels are drawn down
to minimum pool (see Definitions).
This estimate is based on data derived from the City’s Reservoir Storage Model and is reflected in
Figure 1 (figures are provided at the end of report). The model assumes conservation measures are
implemented when supplies are estimated to last three years or less, consistent with the City’s Water
Salinas
Whale Rock
Nacimiento
Groundwater
Recycled
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2013 Water Resources Status Report
Page 2
Shortage Contingency Plan. The various stages of conservation are indicated in Figure 1. The City’s
Water Shortage Contingency Plan details conservation measures related to drought and is an appendix
to the Urban Water Management Plan, adopted June 2011.
2012 Summary
Table 1 summarizes 2012 water demand per source. The total 2012 calendar year water demand
(based on water production figures) was 5,541 acre feet. Water use by category is shown in Chart 1.
Table 1: 2012 City Water Demand Sources
(in acre feet)
Salinas Whale Rock* Nacimiento Groundwater Recycled Total Water Demand
1,959 1,822 1,502 93 165 5,541
*Water delivered to Cal Poly State University is excluded from the City’s Water Demand.
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Page 3
Historical water use is summarized in Table 2, as well as corresponding population, per capita use rate,
and precipitation. The 2012 per capita water use was approximately 109 gallons per capita per day
(gpcd), representing a 5 gpcd increase from the previous year.
The ten‐year average water use is 119 gpcd. Based on policies contained in the General Plan’s Water
and Wastewater Management Element (WWME), the City uses the ten‐year average to project water
required to serve build‐out population.
Table 2: Population Estimates, Water Use & Rainfall
Year Population Total Water Use
(acre feet)
Per Capita
(gpcd)
Rainfall1
(inches)
2003 44,357 5,968 120 16.4
2004 44,298 6,239 126 21.0
2005 44,687 6,098 122 20.8
2006 44,559 5,999 120 17.2
2007 44,433 6,493 130 12.7
2008 44,579 6,359 127 18.1
2009 44,829 6,134 122 18.9
2010 44,948 5,489 109 36.0
2011 45,418 5,285 104 18.9
2012 45,308 5,541 109 21.5
Ten‐year per capita average 119
NOTE:
1. Rainfall amounts for calendar year source: Cal Poly CIMIS Weather Station
Single Family
Residential
40%
Multi Family
Residential
20%
Commercial
Institutional
30%
Landscape
Irrigation
10%
Chart 1: 2012 Water Use by Category
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2013 Water Resources Status Report
Page 4
II. MULTI‐SOURCE WATER SUPPLY
Per WWME Policy A 2.2.1, the City shall utilize
multiple water resources to meet its water supply
needs. 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. Maintaining different
type sources [surface water, recycled water (for
irrigation), ground water] provides greater
reliability and flexibility; as does maintaining
surface water sources in distinct watersheds. The
City has five water sources, achieving the goal of
diversifying its water supply portfolio to meet
current and future community needs.
Water Supply Sources
Salinas & Whale Rock Reservoirs
Salinas and Whale Rock Reservoirs have served as
the City’s primary water supplies for over 50 years.
The County of San Luis Obispo Flood Control and
Water Conservation District (County) provides the
oversight, operations, and maintenance of the
Salinas Dam and water delivery facilities for the
benefit of the City. The City pays the County for the
associated costs for these services. The City
provides the oversight, operations, and
maintenance of the Whale Rock Reservoir for the
benefit of the Whale Rock Commission. The Whale
Rock Commission is a joint powers agency made up
of Cal Poly State University, California Men’s
Colony, and the City. The City draws water from
these two reservoirs in a coordinated manner to
maximize the long‐term water supply available
from these two sources. In addition, the City has
adopted policies in the WWME to account for
reductions in storage capacity at each lake
resulting from siltation.
Nacimiento Reservoir
Water deliveries from the Nacimiento Reservoir began on January 5, 2011. The City has a contractual
right to 3,380 acre feet per year. The County operates and maintains the project that delivers water
from Nacimiento Reservoir to participating agencies (currently cities of Paso Robles and San Luis
Obispo, Atascadero Mutual Water Company, Templeton Community Services District, and County
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
Salinas Dam
Whale Rock
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2013 Water Resources Status Report
Page 5
Service Area 10A (Cayucos)). The Nacimiento Project Commission, which is made up of representatives
from each of the four agencies’ governing boards and County Representative (i.e. County Board of
Supervisors), provides oversight to project operations, maintenance, and the project budget.
Recycled Water
Recycled water use for calendar year 2012 year totaled approximately 165 acre feet, up four percent
from 158 acre feet in 2011. During 2012, two new sites (Olive Garden and Hampton Inn) were
connected to the City’s recycled water distribution system to provide landscape irrigation.
Groundwater
The City used one domestic well in 2012 (Pacific Beach #1 located on Los Osos Valley Road near Pacific
Beach school) to supplement its other potable water supply sources. In addition, the City maintains a
non‐potable well at the City’s Corporation Yard for construction activity use and two non‐potable wells
at the City’s Laguna Lake Golf Course for a portion of the golf course irrigation (additional golf course
irrigation demand is met with recycled water). Per WWME Policy A 3.2.3, the City will continue to use
groundwater for domestic purposes when available, but will not consider this source of supply as a
part of its water resources availability due to limitations for the use of groundwater resources.
Water Resource Availability
Table 3 summarizes the Water Resource Availability (based on WWME Section 3), to serve community
water demand. Calendar Year 2012 water availability totaled 9,985 Acre‐Feet.
Table 3: 2012 Water Resource Availability
Water Resource Acre Feet Description
Salinas & Whale Rock Reservoirs 6,940 Safe Annual Yield 1
Nacimiento Reservoir 3,380 Dependable Yield 2
Recycled Water 165 2012 Annual Usage 3
Siltation from 2010 to 2060 (500) WWME Policy A 4.2.2 4
9,985 2012 Annual Availability
NOTES:
1. Quantity of water which can be withdrawn every year while operating both reservoirs in coordinated operations under
critical drought conditions. Safe Annual Yield determined from computer model, which accounts for siltation loss through
2010 (per WWME Policy A 4.2.1)
2. Dependable Yield is the contractual amount of water the City has rights to from Nacimiento Reservoir.
3. The quantity of recycled water included is the actual prior year’s recycled water usage (2012) per WWME Policy A 7.2.2
4. Reservoir siltation is a natural occurrence that reduces storage capacity over long periods, resulting in the reduction of
safe annual yield.
Water Supply Accounting
Per WWME Section 5, the City will account for water supplies necessary to meet three specific
community needs:
1. Primary water supply,
2. Reliability reserve, and
3. Secondary water supply.
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The primary water supply is defined as the amount of water needed to serve the build‐out population
of the City as identified in the Land Use Element of the General Plan. The quantity of water needed for
the primary water supply is calculated using the ten‐year average of actual per capita water use, shown
in Table 2, and the City’s build‐out population 53,700 (Table 4, 2013 Water and Wastewater
Development Impact Fee Study (as provided by Community Development staff working on LUCE
update), down from 57,200, 1994 Land Use Element to the General Plan, revised 2010. Per WWME
Policy A 5.2.2:
Primary Water Supply:
= Ten Year Average per Capita Water Use x City Build‐out Population
= 118.9 gal/cap‐day x 53,700 cap x 365 day/year x Acre‐Ft/325,853 gal
= 7,152 Acre‐Ft/year
The reliability reserve provides a buffer for future unforeseen or unpredictable long‐term impacts to
the City’s available water supply. The quantity of water for the reliability reserve is established using
twenty percent of the ten‐year average of actual per capita water use and the existing City population
(45,308, 2012 population). The reliability reserve concept is included in the City’s Charter (Section 909)
which identifies that the water may not be used to serve future development, and is defined per
WWME Policy A 5.2.3:
Reliability Reserve:
= Ten Year Average per Capita Water Use x 2012 City Population x 20%
= 118.9 gal/cap‐day x 45,308 cap x 365 day/year x Acre‐Ft/325,853 gal x 20%
= 1,207 Acre‐Ft/year
The secondary water supply is the amount of water remaining from the City’s available water
resources above those needed to meet the primary water supply and reliability reserve. The secondary
supply is identified to meet peak water demand periods or short‐term loss of City water supply
sources, per WWME Policy A 5.2.4:
Secondary Water Supply:
= Current Annual Availability – Primary Water Supply – Reliability Reserve
= 9,985 Acre‐Ft/year A – 7,152 acre‐Ft/year – 1,207 Acre‐Ft/year
= 1,626 Acre‐Ft/year
A.2012 Annual Availability
Water supply accounting is summarized in Table 4.
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Table 4: 2012 Water Supply Accounting
(in acre feet)
Total Primary Water Supply Reliability Reserve Secondary Water Supply
9,985 7,152 1,207 1,626
III. WATER DEMAND MANAGEMENT
The City’s water conservation program is an integral part of its overall water management strategy.
The program has assisted in adding reliability to the water supply system over the years. In the late
1980’s, the City implemented effective water efficiency programs and policies that allowed for
continued community growth and economic development during water‐constrained periods. Although
the City’s investment in a multi‐source water supply portfolio satisfies anticipated build‐out water
demand, water is a valuable resource that should be used wisely.
The following sections describe regulatory requirements and services provided by the water
conservation program.
California Urban Water Conservation Council – Best Management Practices
Historically the City has utilized the California Urban Water Conservation Council’s (CUWCC) Best
Management Practices (BMPs) as defined in the Memorandum of Understanding Regarding Urban
Water Conservation in California (MOU) as a guide for the City’s water conservation program. The
BMPs are programs and services that MOU signatories agree to implement over time. Though BMP
implementation is voluntary, all state regulatory agencies now recognize them as the standard for
compliance with State law. The City has fully implemented the required measures and is thus in
compliance with all applicable State laws.
Water Use Efficiency Legislation
Legislation passed over the years requires water agencies to implement water conservation measures
in order to be eligible for state grants, loans, or assistance. Eligibility for grants and loans apply to both
water and wastewater projects that the City may undertake. A summary of the legislation follows:
AB 1420
Assembly Bill 1420 (Stats. 2007, ch. 628) amended the Urban Water Management Planning Act, Water
Code Section 10610 et seq., to require, effective January 1, 2009, that the terms of, and eligibility for,
any water management grant or loan made to an urban water supplier and awarded or administered
by the Department of Water Resources (DWR), State Water Resources Control Board, or California Bay‐
Delta Authority, be conditioned on the implementation of the water Demand Management Measures
(DMMs) described in Water Code Section 10631(f). DWR was given discretionary authority to
determine whether an urban water supplier is eligible for a grant or loan.
SBx7‐7
Senate Bill x7‐7 was enacted in November 2009, requiring all water suppliers to increase water use
efficiency. The legislation sets an overall goal of reducing per capita urban water use by 20 percent by
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December 31, 2020. The law directs incremental progress towards this goal by reducing per capita
water use by at least ten percent by December 31, 2015. The law states:
Each urban retail water supplier shall develop water use targets and an interim water use target
by July 1, 2011.
An urban retail water supplier shall include in its water management plan, due July 2011, the
baseline daily per capita water use, water use target, interim water use target, and compliance
per capita water use.
Effective 2016, urban retail water suppliers who do not
meet the water conservation requirements established by
this bill are not eligible for state grants or loans.
The City’s Urban Water Management Plan provides a complete
discussion of the legislative requirements. Table 5 summarizes the
per capita targets the City must meet in order to be in compliance
with the law.
Urban Water Management Planning Act
Initially passed in 1984 and amended several times over the years, the Urban Water Management
Planning Act requires water agencies to report on their progress in implementing Water Demand
Management Measures outlined in the law. The law was amended so that full implementation of the
BMPs would be accepted as being in compliance with the part of the law. The City’s 2010 Urban Water
Management Plan provides a complete discussion of the City’s water conservation program and
verification of compliance with the regulations of the act.
Other Regulatory Requirements
The Clean Water State Revolving Fund Requirements
In order to qualify for a loan for any water or wastewater project from the State Water Resources
Control Board, an agency must provide verification that it is in compliance with either the Demand
Management Measures in the Urban Water Conservation Planning Act or the CUWCC BMPs.
2012 Water Conservation Program Highlights
Residential and Commercial Technical Assistance
The most important program the Utilities Conservation Section
offers is its technical assistance and support to the community.
During 2012 the section responded to approximately 1,700
requests for assistance with high water bill, leak detection
assistance, and general consultations regarding customer billing
problems. The requests for consultations are typically received
from people experiencing high water bills, residents
participating in the low income assistance program, or customers requesting a utility bill adjustment
through the Utility Billing Adjustment Committee. Water audits often reveal problems which are then
Utilities Conservation Staff
responded to 1,700 requests for
assistance in 2012
Table 5: 2015 and 2020 Targets
Year Adjusted Per
Capita Target
2015 120 gpcd
2020 117 gpcd
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2013 Water Resources Status Report
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corrected by the property owner resulting in lower water use and reduced water bills. In addition,
approximately 465 utility billing adjustment requests were processed during 2011.
Public Information & Education
In an ongoing effort to educate the public, the City
provides informational brochures on a variety of
water conservation, water quality, energy
conservation, and recycling topics upon request.
Additionally, a quarterly newsletter is produced
which focuses on current information regarding
water, wastewater, stormwater, and solid waste
issues. The newsletter is mailed to approximately
21,000 households. Additional information was
distributed through paid media advertising, public
service announcements, and participation at
Farmer’s Market, home shows, etc.
The Utilities Department continues to offer a water education program within San Luis Coastal Unified
School District. The program targets third through fifth grade students and compliments the study of
water within the School District’s existing curriculum. Teachers have been enthusiastic about the
program, particularly with the field trip to the Water Reclamation Facility.
IV. PROJECTED WATER SUPPLY SITUATION
Reservoir Storage Curve
The Reservoir Storage Curve is integral to the City's annual water resource analysis. It is based on a
computer model used to estimate the City's future reservoir storage in Salinas and Whale Rock Reservoirs,
utilizing historical drought weather patterns, water use projections, reservoir data, and available water
supplies from Nacimiento Reservoir, recycled water, and limited groundwater. Figure 1 shows the
Reservoir Storage Curve. The model assumes implementation of Stage I conservation when supplies are
projected to last only three years. Stage II and III conservation measures are implemented when water
supplies are estimated to last only two years and one year, respectively (as shown on Figure 1/
conservation stages as defined in Section 8 of the 2010 Urban Water Management Plan). The model was
updated to reflect the City's current water storage and assumptions relative to water demands.
Assuming the onset of an extended drought, the model predicts current water supplies will last into the
year 2021 until Whale Rock and Salinas reservoirs are drawn down to minimum pool. (Figure 1).
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2013 Water Resources Status Report
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V. SUMMARY
As of September 1, 2013, the City’s surface water supplies from Salinas and Whale Rock Reservoirs are
at 53 percent of maximum storage. Assuming the onset of an extended drought, currently water
supplies are projected to last into the year 2021. With its multi‐source water policy, the City has
implemented a long‐term strategy which will ensure a reliable supply of water to meet the current and
future needs of the community.
ATTACHMENTS:
1. Definitions & Information
2. Figure 1
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2013 Water Resources Status Report
Attachment
ATTACHMENT: DEFINITIONS & INFORMATION
Safe Annual Yield:
The maximum quantity of water which can be delivered from the water source each year during a critical
dry period (i.e. historical drought period).
Minimum Pool:
Minimum amount of water in Whale Rock or Salinas Reservoirs below which water deliveries must be
stopped. This amount is established at 2,000 acre feet which is left in the reservoirs to support aquatic
habitat and other wildlife.
Acre Foot:
One acre foot = 325,851 gallons
Enough water to cover a football field with one foot of
water
Enough water to serve approximately four average
single‐family homes (in San Luis Obispo) per year
Gallons per Capita per Day (gpcd):
Calculation = Total Acre Feet x 325,851
City Population x 365
Water Demand (acre feet per year):
Calculation = gpcd x Current City Population x 365
325,851
Salinas Reservoir:
Maximum Storage Capacity = 23,842.9 acre feet
Minimum Pool = storage amount when water extractions must cease = 2,000 acre feet
Surface Area = 730 acres
Drainage Area = 112 square miles = 71,700 acres
Whale Rock Reservoir:
Maximum Storage Capacity = 40,662 acre feet
Minimum Pool = storage amount when water extractions must cease = 2,000 acre feet
Surface Area = 594 acres
Drainage Area = 20.3 square miles = 13,000 acres
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