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Appendix L2
Water Supply Assessment
OTAY WATER DISTRICT
WATER SUPPLY ASSESSMENT AND
VERIFICATION REPORT
for the
City of Chula Vista
Sunbow II, Phase 3 Project
D1065-090447
Prepared by:
Lisa Coburn-Boyd
Environmental Compliance Specialist
and
Bob Kennedy, P.E.
Engineering Manager
Otay Water District
In consultation with
Dexter Wilson Engineering, Inc.
And
San Diego County Water Authority
November 2020
ExhibitC
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
Otay Water District
Water Supply Assessment and Verification Report
November 2020
Sunbow II, Phase 3 Project
Table of Contents
Executive Summary .................................................................................................................. 1
Section 1 - Purpose .................................................................................................................... 5
Section 2 - Findings ................................................................................................................... 6
Section 3 - Project Description ................................................................................................ 8
Section 4 – Otay Water District ............................................................................................... 9
Section 5 – Historical and Projected Water Demands ........................................................ 12
5.1 Demand Management (Water Conservation) .....................................................
Section 6 - Existing and Projected Supplies ......................................................................... 19
6.1 Metropolitan Water District of Southern California 2015 Urban Water
Management Plan ......................................................................................... 20
6.1.2 MWD Capital Investment Plan .......................................................... 21
6.2 San Diego County Water Authority Regional Water Supplies ................ 22
6.2.1 Availability of Sufficient Supplies and Plans for Acquiring Additional
Supplies ............................................................................................. 23
6.2.1.2 All-American Canal and Coachella Canal Lining Projects .. 30
6.2.1.3 Carlsbad Seawater Desalination Project ............................... 34
6.2.2 Water Authority Capital Improvement Program and Financial
Information ........................................................................... 37
6.3 Otay Water District ...................................................................................... 38
6.3.1 Availability of Sufficient Supplies and Plans for Acquiring Additional
Supplies ............................................................................................. 38
6.3.1.1 Imported and Regional Supplies ........................................... 39
6.3.1.2 Recycled Water Supplies ...................................................... 41
Section 7 – Conclusion: Availability of Sufficient Supplies ................................................ 48
Source Documents ................................................................................................................... 53
Appendices
Appendix A: Sunbow II, Phase 3 Project Vicinity Map
Appendix B: Sunbow II, Phase 3 Project Development Plan
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
1
Otay Water District
Water Supply Assessment and Verification Report
November 2020
Sunbow II, Phase 3 Project
Executive Summary
The Otay Water District (Otay WD) prepared this Water Supply Assessment and Verification
Report (WSA&V Report) at the request of the City of Chula Vista (City) for the Sunbow II,
Phase 3 project.
Sunbow II, Phase 3 Project Overview and Water Use
The Sunbow II, Phase 3 project is located within the jurisdictions of the Otay WD, the San
Diego County Water Authority (Water Authority), and the Metropolitan Water District of
Southern California (MWD). In order to obtain permanent imported water supply service,
land areas are required to be within the jurisdictions of the Otay WD, Water Authority, and
MWD.
The proposed project entitlement includes a Chula Vista General Plan Amendment, a Sunbow
General Development Plan Amendment, a Sunbow Sectional Planning Area Amendment,
Rezone and tentative map. The proposed project also includes a Chula Vista MSCP
Boundary Adjustment to implement minor adjustments to the development limits and the
adjacent MSCP Preserve areas that would result in a 0.7-acre increase to MSCP Preserve
Area. The City is having an EIR prepared for development of the 135.7-acre site (Sunbow II,
Phase 3 project). The land use plan previously proposed industrial development, but now
proposes a residential land use with 718 multi-family units. The project is located along
Olympic Parkway in the City of Chula Vista.
The project proposes 718 multi-family residential units within a project area of 135.7 acres.
The proposed development footprint would be approximately 69.0 acres, which would consist
of 44.2 acres of residential, a 0.9-acre Community Purpose Facility (CPF) site, 5.9 acres of
public streets and 18 acres of manufactured slopes/basins/wetland resource and associated
buffer area. The proposed project also includes approximately 3.9 acres of proposed Poggi
Canyon Easement area and 62.8 acres of MSCP Preserve area.
The expected potable water demand for the Sunbow II, Phase 3 project is 122,060 gallons per
day (gpd) or about 136.7 acre feet per year (AFY). This is 84.7 AFY higher than the
projected demands in the District’s 2015 Water Facilities Master Plan which estimated 52
AFY for 54.7 acres of industrial use.
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The 84.7 AFY increase in demand is accounted for through the Accelerated Forecasted
Growth demand increment of the Water Authority’s 2015 UWMP. As documented in the
Water Authority’s 2015 UWMP, the Water Authority is planning to meet future and existing
demands which include the demand increment associated with the accelerated forecasted
growth. The Water Authority will assist its member agencies in tracking the environmental
documents provided by the agencies that include water supply assessments and verifications
reports that utilize the accelerated forecasted growth demand increment to demonstrate
supplies for the development. In addition, the next update of the demand forecast for the
Water Authority’s 2020 UWMP will be based on SANDAG’s most recently updated forecast,
which will include the Project. Therefore, based on the findings from the Otay WD’s 2015
UWMP and the Water Authority’s 2015 UWMP, this project will result in no unanticipated
demands.
Recycled water will be used for irrigation of manufactured slopes and common areas. The
projected recycled water demand for the Sunbow II, Phase 3 project is 24,510 gpd, or about
27.5 AFY.
Planned Imported Water Supplies from the Water Authority and MWD
The Water Authority and MWD have an established process that ensures supplies are being
planned to meet future growth. Any annexations and revisions to established land use plans
are captured in the San Diego Association of Governments (SANDAG) updated forecasts for
land use planning, demographics, and economic projections. SANDAG serves as the
regional, intergovernmental planning agency that develops and provides forecast information.
The Water Authority and MWD update their demand forecasts and supply needs based on the
most recent SANDAG forecast approximately every five years to coincide with preparation of
their UWMP ’s. Prior to the next forecast update, local jurisdictions with land use authority
may require water supply assessment and/or verification reports for proposed land
developments that are not within the Otay WD, Water Authority, or MWD jurisdictions (i.e.
pending or proposed annexations) or that have revised land use plans with either lower or
higher development intensities than reflected in the existing growth forecasts. Proposed land
areas with pending or proposed annexations, or revised land use plans, typically result in
creating higher demand and supply requirements than previously anticipated. The Otay WD,
Water Authority, and MWD next demand forecast and supply requirements and associated
planning documents would then capture any increase or decrease in demands and required
supplies as a result of annexations or revised land use planning decisions.
An important planning document utilized by MWD, the Water Authority and Otay WD is the
Integrated Resources Plan (IRP) which describes an agency’s long-term water plan. MWD’s
2015 IRP offers an adaptive management strategy to protect the region from future supply
shortages. This adaptive management strategy has five components: achieve additional
conservation savings, develop additional local water supplies, maintain Colorado River
Aqueduct supplies, stabilize State Water Project supplies, and maximize the effectiveness of
storage and transfer. MWD’s 2015 IRP has a plan for identifying and implementing
additional resources that expand the ability for MWD to meet future changes and challenges
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as necessary to ensure future reliability of supplies. The proper management of these
resources help to ensure that the southern California region, including San Diego County, will
have adequate water supplies to meet long-term future demands.
Another important planning document is the UWMP. The California Urban Water
Management Planning Act (Act), which is included in the California Water Code, requires all
urban water suppliers within the state to prepare an UWMP and update it every five years.
The purpose and importance of the UWMP has evolved since it was enacted in 1983. State
agencies and the public frequently use the document to determine if agencies are planning
adequately to reliably meet future demands. As such, UWMPs serve as an important element
in documenting supply availability for the purpose of compliance with state laws, Senate Bills
610 and 221, linking water supply sufficiency to large land-use development approval.
Agencies must also have a UWMP prepared, pursuant to the Act, in order to be eligible for
state funding and drought assistance.
MWD’s 2015 UWMP Findings state that MWD has supply capabilities that would be
sufficient to meet expected demands from 2020 through 2040. MWD has plans for supply
implementation and continued development of a diversified resource mix including programs
in the Colorado River Aqueduct, State Water Project, Central Valley Transfers, local resource
projects, and in-region storage that enables the region to meet its water supply needs.
The County Water Authority Act, Section 5 subdivision 11, states that the Water Authority
“as far as practicable, shall provide each of its member agencies with adequate supplies of
water to meet their expanding and increasing needs.”
As part of preparation of a written water supply assessment report, an agency’s water shortage
contingency analysis should be considered in determining sufficiency of supply. Section 11
of the Water Authority’s 2015 UWMP Update contain a detailed shortage contingency
analysis that addresses a regional catastrophic shortage situation and drought management.
The analysis demonstrates that the Water Authority and its member agencies, through the
Integrated Contingency Plan, Emergency Storage Project, and Water Shortage Contingency
Plan are taking actions to prepare for and appropriately handle an interruption of water
supplies. The Water Shortage Contingency Plan provides the Water Authority and its
member agencies with a series of potential actions to take when faced with a shortage of
imported water supplies from MWD due to prolonged drought or other supply shortfall
conditions. The actions will help the region avoid or minimize the impacts of shortages and
ensure an equitable allocation of supplies.
Water supply agencies throughout California continue to face climate, environmental, legal,
and other challenges that impact water source supply conditions, such as the court rulings
regarding the Sacramento-San Joaquin Delta issues and reoccurring droughts impacting the
western states. Even with these ever-present challenges, the Water Authority and MWD,
along with Otay WD fully intend to have sufficient, reliable supplies to serve demands.
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Otay Water District Water Supply Development Program
In evaluating the availability of sufficient water supply, the Sunbow II, Phase 3 project will be
required to participate in the water supply development program being implemented by the
Otay WD. This is intended to be achieved through financial participation in several local
and/or regional water supply development projects envisioned by the Otay WD. These water
supply projects are in addition to those identified as sustainable supplies in the current Water
Authority and MWD UWMP, IRP, Master Plans, and other planning documents, and are in
response to the regional water supply issues. These new water supply projects are not
currently developed and are in various stages of the planning process. Imported water
supplies along with the development of these additional Otay WD water supply development
projects supplies are intended to increase water supplies to serve the Sunbow II, Phase 3
project water supply needs and that of other similar development projects. The Otay WD
water supply development program includes but is not limited to projects such as the Middle
Sweetwater River Basin Groundwater Well project, the Rancho del Rey Groundwater Well
Project, the Otay Mesa Lot 7 Groundwater Well Project, and the Otay WD Rosarito Ocean
Desalination Facility Project. The Water Authority and MWD’s next forecasts and supply
planning documents would capture any increase in water supplies resulting from any new
water resources developed by the Otay WD.
Findings
The WSA&V Report identifies and describes the processes by which water demand
projections for the proposed Sunbow II, Phase 3 project will be fully included in the water
demand and supply forecasts of the Urban Water Management Plans and other water
resources planning documents of the Water Authority and MWD. Water supplies necessary
to serve the demands of the proposed project, along with existing and other projected future
users, as well as the actions necessary and status to develop these supplies, have been
identified in the Sunbow II, Phase 3 project WSA&V Report and will be included in the
future water supply planning documents of the Water Authority and MWD.
This WSA&V Report includes, among other information, an identification of existing water
supply entitlements, water rights, water service contracts, water supply projects, or
agreements relevant to the identified water supply needs for the proposed Sunbow II, Phase 3
project. The WSA&V Report demonstrates and documents that sufficient water supplies are
planned for and are intended to be available over a 20-year planning horizon, under normal
conditions and in single and multiple dry years to meet the projected demand of the Sunbow
II, Phase 3 project and the existing and other planned development projects to be served by
the Otay WD.
Accordingly, after approval of a WSA&V Report for the Sunbow II, Phase 3 project by the
Otay WD Board of Directors (Board), the WSA&V Report may be used to comply with the
requirements of the legislation enacted by Senate Bills 610 and 221 as follows:
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1. Senate Bill 610 Water Supply Assessment: The Otay WD Board approved WSA&V
Report may be incorporated into the California Environmental Quality Act (CEQA)
Environmental Impact Report (EIR) compliance process for the Sunbow II, Phase 3
project as a water supply assessment report consistent with the requirements of the
legislation enacted by SB 610. The City, as lead agency under CEQA for the Sunbow
II, Phase 3 project EIR and Alternatives, may cite the approved WSA&V Report as
evidence that a sufficient water supply is planned for and is intended to be made
available to serve the Sunbow II, Phase 3 project.
2. Senate Bill 221 Water Supply Verification: The Otay WD Board approved WSA&V
Report may be incorporated into the City’s Tentative Map approval process for the
Sunbow II, Phase 3 project as a water supply verification report, consistent with the
requirements of the legislation enacted by SB 221. The City, within their process of
approving the Sunbow II, Phase 3 project Revised Tentative Map, may cite the
approved WSA&V Report as verification of intended sufficient water supply to serve
the Sunbow II, Phase 3 project.
Section 1 - Purpose
The City of Chula Vista is having an environmental impact report (EIR) prepared for the
development of the 135.7-acre project (Sunbow II, Phase 3 project). The project is located
along Olympic Parkway in the City of Chula Vista.
The City requested that the Otay WD prepare a Water Supply Assessment and Verification
(WSA&V) Report for the Sunbow II, Phase 3 project. This WSA&V Report is being
prepared for the proposed project concurrent with the Specific Plan Amendment and revised
Tentative Map processing through the City of Chula Vista. The Sunbow II, Phase 3 project
description is provided in Section 3 of this WSA&V Report.
This WSA&V Report for the Sunbow II, Phase 3 project has been prepared by the Otay WD
in consultation with Dexter Wilson Engineering, Inc., the Water Authority, and the City
pursuant to Public Resources Code Section 21151.9 and California Water Code Sections
10631, 10656, 10910, 10911, 10912, and 10915 referred to as Senate Bill (SB) 610 and
Business and Professions Code Section 11010 and Government Code Sections 65867.5,
66455.3, and 66473.7 referred to as SB 221. SB 610 and SB 221 amended state law, effective
January 1, 2002, is intended to improve the link between the information on water supply
availability and certain land use decisions made by cities and counties. SB 610 requires that
the water purveyor of the public water system prepare a water supply assessment to be
included in the CEQA documentation and approval process of certain proposed projects. SB
221 requires affirmative written verification from the water purveyor of the public water
system that sufficient water supplies are to be available for certain residential subdivisions of
property prior to approval of a tentative map. The requirements of SB 610 and SB 221 are
being addressed by this WSA&V Report.
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The City also requested, since the requirements of SB 610 and SB 221 are substantially
similar, that Otay WD prepare both the water supply assessment and verification
concurrently.
This WSA&V Report evaluates water supplies that are planned to be available during normal,
single dry year, and multiple dry water years during a 20-year planning horizon to meet
existing demands, expected demands of the Sunbow II, Phase 3 project, and reasonably
foreseeable planned future water demands to be served by Otay WD. The Otay Water District
Board of Directors approved WSA&V Report is planned to be used by the City in its
evaluation of the Sunbow II, Phase 3 project under the CEQA approval process procedures.
Section 2 - Findings
The Otay WD prepared this WSA&V Report at the request of the City for Sunbow II, Phase 3
project.
The Sunbow II, Phase 3 project is located within the jurisdictions of the Otay WD, the Water
Authority, and MWD. To obtain permanent imported water supply service, land areas are
required to be within the jurisdictions of the Otay WD, Water Authority, and MWD to utilize
imported water supply.
The expected potable water demand for the Sunbow II, Phase 3 project is 122,060 gallons per
day (gpd) or about 136.7 acre feet per year (AFY). This is 84.7 AFY higher than the demand
estimate in the District’s 2015 WFMP Update which estimated 52 AFY. The projected
recycled water demand for the Sunbow II, Phase 3 project is 24,510 gpd, or about 27.5 AFY.
The 84.7 AFY increase in demand is accounted for through the Accelerated Forecasted
Growth demand increment of the Water Authority’s 2015 UWMP. As documented in the
Water Authority’s 2015 UWMP, the Water Authority is planning to meet future and existing
demands which include the demand increment associated with the accelerated forecasted
growth. The Water Authority will assist its member agencies in tracking the environmental
documents provided by the agencies that include water supply assessments and verifications
reports that utilize the accelerated forecasted growth demand increment to demonstrate
supplies for the development. In addition, the next update of the demand forecast for the
Water Authority’s 2020 UWMP will be based on SANDAG’s most recently updated forecast,
which will include the Project. Therefore, based on the findings from the Otay WD’s 2015
UWMP and the Water Authority’s 2015 UWMP, this project will result in no unanticipated
demands.
The Water Authority and MWD have an established process that ensures supplies are being
planned to meet future growth. Any annexations and revisions to established land use plans
are captured in the San Diego Association of Governments (SANDAG) updated forecasts for
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land use planning, demographics, and economic projections. SANDAG serves as the
regional, intergovernmental planning agency that develops and provides forecast information.
The Water Authority and MWD update their demand forecasts and supply needs based on the
most recent SANDAG forecast approximately every five years to coincide with preparation of
their urban water management plans. Prior to the next forecast update, local jurisdictions may
require water supply assessment and/or verification reports for proposed land developments
that are not within the Otay WD, Water Authority, or MWD jurisdictions (i.e. pending or
proposed annexations) or that have revised land use plans with lower or higher land use
intensities than reflected in the existing growth forecasts. Proposed land areas with pending
or proposed annexations, or revised land use plans, typically result in creating higher demand
and supply requirements than anticipated. The Otay WD, the Water Authority, and MWD
next demand forecast and supply requirements and associated planning documents would then
capture any increase or decrease in demands and required supplies as a result of annexations
or revised land use planning decisions.
This process is utilized by the Water Authority and MWD to document the water supplies
necessary to serve the demands of the Sunbow II, Phase 3 project, along with existing and
other projected future users, as well as the actions necessary to develop any required water
supplies. Through this process the necessary demand and supply information is thus assured
to be identified and incorporated within the water supply planning documents of the Water
Authority and MWD.
This WSA&V Report includes, among other information, an identification of existing water
supply entitlements, water rights, water service contracts, proposed water supply projects, and
agreements relevant to the identified water supply needs for the proposed Sunbow II, Phase 3
project. This WSA&V Report incorporates by reference the current Urban Water
Management Plans and other water resources planning documents of the Otay WD, the Water
Authority, and MWD. The Otay WD prepared this WSA&V Report to assess and document
that sufficient water supplies are planned for and are intended to be acquired to meet projected
water demands of the Sunbow II, Phase 3 project as well as existing and other reasonably
foreseeable planned development projects within the Otay WD for a 20-year planning
horizon, in normal supply years and in single dry and multiple dry years.
The Otay Water District 2015 UWMP includes a water conservation component to comply
with Senate Bill 7 of the Seventh Extraordinary Session (SBX 7-7), which became effective
February 3, 2010. This new law was the water conservation component to the Delta
legislation package, and seeks to achieve a 20 percent statewide reduction in urban per capita
water use in California by December 31, 2020. Specifically, SBX 7-7 from this Extraordinary
Session requires each urban retail water supplier to develop urban water use targets to help
meet the 20 percent reduction goal by 2020 (20x2020), and an interim water reduction target
by 2015.
Otay WD adopted Method 1 to set its 2015 interim and 2020 water use targets. Method 1
requires setting the 2020 water use target to 80 percent of baseline per capita water use target
as provided in the State’s 20x2020 Water Conservation Plan. The Otay WD 2015 target was
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172 gpcd which it met (2015 actual was 124 gpcd) and the 2020 gpcd target (80 percent of
baseline) is 153 gpcd. The Otay WD’s recent per capita water use has been declining and
current water use meets the 2020 target as calculated using Method 1. The decline in per
capita water use was due to drought water use restrictions, increased water costs, and
economic conditions. Otay WD’s effective water use awareness campaign and enhanced
conservation mentality of its customers has resulted in long-term carryover of these reduced
consumption rates.
Based on a normal water supply year, the five-year increments for a 20-year projection
indicate projected potable and recycled water supply is being planned for and is intended to be
acquired to meet the estimated water demand targets of the Otay WD (42,720 acre-feet (ac-ft)
in 2020 to 57,582 ac-ft in 2040) per the Otay Water District 2015 UWMP. Based on dry year
forecasts, the estimated water supply is also being planned for and is intended to be acquired
to meet the projected water demand, during single dry and multiple dry year scenarios. On
average, the dry-year demands are about 6.64 percent higher than the normal year demands.
The Otay WD recycled water supply is assumed to be drought-proof and not subject to
reduction during dry periods.
Together, these findings assess, demonstrate, and document that sufficient water supplies are
planned for and are intended to be acquired for the Sunbow II, Phase 3 project. In addition,
the actions necessary to develop these supplies are and will be further documented, to serve
the proposed project and the existing and other reasonably foreseeable planned development
projects within the Otay WD in both normal and single and multiple dry year forecasts for a
20-year planning horizon.
Section 3 - Project Description
The Sunbow II, Phase 3 project is located along Olympic Parkway in the City of Chula Vista.
Refer to Appendix A for a vicinity map of the proposed Sunbow II, Phase 3 project. The
project is proposed to be located on 135.7 acres. Although the proposed development is
located within the City and subject to the City’s land use jurisdiction, the Otay WD is the
potable and recycled water purveyor. The Sunbow II, Phase 3 project is within the
jurisdictions of the Otay WD, the Water Authority, and MWD.
The Sunbow II, Phase 3 project proposes 718 multi-family residential units within a project
area of 135.7 acres. The proposed development footprint would be approximately 69.0 acres,
which would consist of 44.2 acres of residential, a 0.9-acre Community Purpose Facility
(CPF) site, 5.9 acres of public streets and 18 acres of manufactured slopes/basins/wetland
resource and associated buffer area. The proposed project also includes approximately 3.9
acres of proposed Poggi Canyon Easement area and 62.8 acres of MSCP Preserve area.
The City has discretionary authority on land use decisions for the Sunbow II, Phase 3 project
and can establish actions and/or permit approval requirements. The projected potable water
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demands associated with the Sunbow II, Phase 3 project EIR has considered the anticipated
City discretionary actions and/or permit approvals and are incorporated into and used in this
WSA&V Report. The water demands for the proposed Sunbow II, Phase 3 project are
included in the projected water demand estimates provided in Section 5 – Historical and
Projected Water Demands.
Section 4 – Otay Water District
The Otay WD is a municipal water district formed in 1956 pursuant to the Municipal Water
District Act of 1911 (Water Code §§ 71000 et seq.). The Otay WD joined the Water
Authority as a member agency in 1956 to acquire the right to purchase and distribute imported
water throughout its service area. The Water Authority is an agency responsible for the
wholesale supply of water to its 24 public agency members in San Diego County.
The Otay WD currently meets all its potable demands with imported treated water from the
Water Authority. The Water Authority is the agency responsible for the supply of imported
water into San Diego County through its membership in MWD. The Water Authority
currently obtains about 40% of its imported supply from MWD but is in the process of further
diversifying its available supplies.
The Otay WD provides water service to residential, commercial, industrial, and agricultural
customers, and for environmental and fire protection uses. In addition to providing water
throughout its service area, Otay WD also provides sewage collection and treatment services
to a portion of its service area known as the Jamacha Basin. The Otay WD also owns and
operates the Ralph W. Chapman Water Reclamation Facility (RWCWRF) which has an
effective treatment capacity of 1.2 million gallons per day (mgd) or about 1,300 acre feet per
year to produce recycled water. On May 18, 2007, an additional source of recycled water
supply of up to 6 mgd, or about 6,720 acre feet per year, became available to Otay WD from
the City of San Diego’s South Bay Water Reclamation Plant (SBWRP).
The Otay WD jurisdictional area is generally located within the south central portion of San
Diego County and includes approximately 125 square miles. The Otay WD serves portions of
the unincorporated communities of southern El Cajon, La Mesa, Rancho San Diego, Jamul,
Spring Valley, Bonita, and Otay Mesa, the eastern portion of the City of Chula Vista and a
portion of the City of San Diego on Otay Mesa. The Otay WD jurisdiction boundaries are
roughly bounded on the north by the Padre Dam Municipal Water District, on the northwest
by the Helix Water District, and on the west by the South Bay Irrigation District (Sweetwater
Authority) and the City of San Diego. The southern boundary of Otay WD is the international
border with Mexico.
The planning area addressed in the Otay WD WFMP Update and the Otay WD 2015 UWMP
includes both the land within the jurisdictional boundary of the Otay WD and those areas
outside of the present Otay WD boundaries considered to be in the Area of Influence of the
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Otay WD. Figure 3-1 contained within the Otay WD 2015 UWMP shows the jurisdictional
boundary of the Otay WD and the Area of Influence. The planning area is approximately 143
square miles, of which approximately 125 square miles are within the Otay WD current
boundaries and approximately 18 square miles are in the Area of Influence. The area east of
Otay WD is rural and currently not within any water purveyor jurisdiction and potentially
could be served by the Otay WD in the future if the need for imported water becomes
necessary, as is the case for the Area of Influence.
The City of Chula Vista, the City of San Diego, and the County of San Diego are the three
land use planning agencies within the Otay WD jurisdiction. Data on forecasts for land use
planning, demographics, economic projections, population, and the future rate of growth
within Otay WD were obtained from the San Diego Association of Governments (SANDAG).
SANDAG serves as the regional, intergovernmental planning agency that develops and
provides forecast information through the year 2050. Population growth within the Otay WD
service area is expected to increase from the 2015 figure of 217,339 to an estimated 285,340
by 2040. Land use information used to develop water demand projections are based upon
Specific or Sectional Planning Areas, the Otay Ranch General Development Plan/Sub-
regional Plan, East Otay Mesa Specific Plan Area, San Diego County Community Plans, and
City of San Diego, City of Chula Vista, and County of San Diego General Plans.
The Otay WD long-term historic growth rate has been approximately 4 percent. The growth
rate had slowed due to economic conditions and is expected to slow as the inventory of
developable land is diminished.
Climatic conditions within the Otay WD service area are characteristically Mediterranean
near the coast, with mild temperatures year-round. Inland areas are both hotter in summer and
cooler in winter, with summer temperatures often exceeding 90 degrees and winter
temperatures occasionally dipping to below freezing. Most of the region’s rainfall occurs
during the months of December through March. Average annual rainfall is approximately
10.08 inches per year.
Historic climate data were obtained from the Western Regional Climate Center for Station
042706 (El Cajon). This station was selected because its annual temperature variation is
representative of most of the Otay WD service area. While there is a station in the City of
Chula Vista, the temperature variation at the City of Chula Vista station is more typical of a
coastal environment than the conditions in most of the Otay WD service area.
Urban Water Management Plan
In accordance with the California Urban Water Management Planning Act and recent
legislation, the Otay WD Board of Directors adopted an UWMP in June 2016 and
subsequently submitted the plan to the California Department of Water Resources (DWR).
As required by law, the Otay Water District 2015 UWMP includes projected water supplies
required to meet future demands through 2040. In accordance with Water Code Section
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10910 (c)(2) and Government Code Section 66473.7 (c)(3), information from the Otay WD
2015 UWMP along with supplemental information from the Otay WD WFMP Update have
been utilized to prepare this WSA Report and are incorporated herein by reference.
The state Legislature passed Senate Bill 7 as part of the Seventh Extraordinary Session (SBX
7-7) on November 10, 2009, which became effective February 3, 2010. This new law was the
water conservation component to the Delta legislation package and seeks to achieve a 20
percent statewide reduction in urban per capita water use in California by December 31, 2020.
Specifically, SBX 7-7 from this Extraordinary Session requires each urban retail water
supplier to develop urban water use targets to help meet the 20 percent reduction goal by 2020
(20x2020), and an interim water reduction target by 2015.
The SBX 7-7 target setting process includes the following: (1) baseline daily per capita water
use; (2) urban water use target; (3) interim water use target; (4) compliance daily per capita
water use, including technical bases and supporting data for those determinations. In order
for an agency to meet its 2020 water use target, each agency can increase its use of recycled
water to offset potable water use and also step up its water conservation measures. The
required water use targets for 2020 and an interim target for 2015 are determined using one of
four target methods – each method has numerous methodologies.
In 2015, urban retail water suppliers were required to report interim compliance followed by
actual compliance in 2020. Interim compliance is halfway between the baseline water use and
2020 target. Baseline, target, and compliance-year water use estimates are required to be
reported in gallons per capita per day (gpcd).
Failure to meet adopted targets will result in the ineligibility of a water supplier to receive
grants or loans administered by the State unless one (1) of two (2) exceptions is met.
Exception one (1) states a water supplier may be eligible if they have submitted a schedule,
financing plan, and budget to DWR for approval to achieve the per capita water use
reductions. Exception two (2) states a water supplier may be eligible if an entire water service
area qualifies as a disadvantaged community.
Otay WD adopted Method 1 to set its 2015 interim and 2020 water use targets. Method 1
requires setting the 2020 water use target to 80 percent of baseline per capita water use target
as provided in the State’s 20x2020 Water Conservation Plan. The Otay WD was well below
its required 2015 target of 172 gpcd, with an actual 2015 gpcd of 124. The 2020 gpcd target
which is 80 percent of baseline is 153 gpcd.
The Otay WD’s recent per capita water use has been declining to the point where current
water use meets the 2020 target for Method 1. The decline in per capita water use was due to
drought water use restrictions, increased water costs, and economic conditions. Otay WD’s
effective water use awareness campaign and the enhanced conservation mentality of its
customers has resulted in long-term carryover of these reduced consumption rates.
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Section 5 – Historical and Projected Water Demands
The projected demands for Otay WD are based on Specific or Sectional Planning Areas, the
Otay Ranch General Development Plan/Sub-regional Plan, the East Otay Mesa Specific Plan
Area, San Diego County Community Plans, and City of San Diego, City of Chula Vista, and
County of San Diego General Plans. This land use information is also used by SANDAG as
the basis for its most recent forecast data. This land use information was utilized for the
preparation of the Otay Water District WFMP Update and Otay Water District 2015 UWMP
to develop the forecasted demands and supply requirements.
In 1994, the Water Authority selected the Institute for Water Resources-Municipal and
Industrial Needs (MAIN) computer model to forecast municipal and industrial water use for
the San Diego region. The MAIN model uses demographic and economic data to project
sector-level water demands (i.e. residential and non-residential demands). This econometric
model has over a quarter of a century of practical application and is used by many cities and
water agencies throughout the United States. The Water Authority’s version of the MAIN
model was modified to reflect the San Diego region’s unique parameters and is known as
CWA-MAIN.
The foundation of the water demand forecast is the underlying demographic and economic
projections. This was a primary reason why, in 1992, the Water Authority and SANDAG
entered into a Memorandum of Agreement (MOA) in which the Water Authority agreed to
use the SANDAG current regional growth forecast for water supply planning purposes. In
addition, the MOA recognizes that water supply reliability must be a component of San Diego
County’s regional growth management strategy required by Proposition C, as passed by the
San Diego County voters in 1988. The MOA ensures a strong linkage between local general
plan land use forecasts and water demand projections and resulting supply needs for the San
Diego region.
Consistent with the previous CWA-MAIN modeling efforts, on October 15, 2013, the
SANDAG Board of Directors accepted the Series 13: 2050 Regional Growth Forecast. The
2050 Regional Growth Forecast will be used by SANDAG as the foundation for the next
Regional Comprehensive Plan update. SANDAG forecasts were used by local governments
for planning, including the Water Authority 2015 UWMP update.
The municipal and industrial forecast also included an updated accounting of projected
conservation savings based on projected regional implementation of the California Urban
Water Conservation Council (CUWCC) Best Management Practices and SANDAG
demographic information for the period 2015 through 2050. These savings estimates were
then factored into the baseline municipal and industrial demand forecast.
Agricultural demand projections were developed through a cooperative effort between Water
Authority staff, Water Authority member agencies, SANDAG, County of San Diego
Agricultural Weights and Measures, and the California Avocado Commission. Forecast driver
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variables include irrigated acreage within the Water Authority’s service area, estimated crop
type distribution, and calculated historic water-use factors. SANDAG’s projection of
agricultural land conversions to other land use categories provides the long-term trend in
acreage used to forecast agricultural water use. The total agricultural forecast is then separated
into two categories: (1) projected demands in the Water Authority’s Transitional Special
Agricultural Water Rate (TSAWR) program and (2) demands under the Water Authority M&I
rate or agricultural demands met through local supplies.
The Water Authority and MWD update their water demand and supply projections within
their jurisdictions utilizing the SANDAG most recent growth forecast to project future water
demands. This provides for the important strong link between demand and supply projections
to the land use plans of the cities and the county. This provides for consistency between the
retail and wholesale agencies water demand projections, thereby ensuring that adequate
supplies are and will be planned for the Otay WD existing and future water users. Existing
land use plans, any revisions to land use plans, and annexations are captured in the SANDAG
updated forecasts. The Water Authority and MWD update their demand forecasts based on
the SANDAG most recent forecast approximately every five years to coincide with
preparation of their urban water management plans. Prior to the next forecast update, local
jurisdictions may require water supply assessment and/or verification reports consistent with
Senate Bills 610 and 221 for proposed land use developments that either have pending or
proposed annexations into the Otay WD, Water Authority, and MWD or that have revised
land use plans than originally anticipated. The Water Authority and MWD’s next forecasts
and supply planning documents would then capture any increase or decrease in demands
caused by annexations or revised land use plans.
In evaluating the availability of sufficient water supply, the Sunbow II, Phase 3 project
proponents are required to participate in the development of alternative water supply
project(s). This can be achieved through payment of the New Water Supply Fee adopted by
the Otay WD Board in May 2010. These water supply projects are in addition to those
identified as sustainable supplies in the current Water Authority and MWD UWMP, IRP,
Master Plans, and other planning documents. These new water supply projects are in
response to the regional water supply issues related to the Sacramento-San Joaquin Delta and
the current ongoing western states drought conditions. These additional water supply projects
are not currently developed and are in various stages of the planning process. A few
examples of these alternative water supply projects include the Middle Sweetwater River
Basin Groundwater Well project, the Rancho del Rey Groundwater Well Project, the Otay
Mesa Lot 7 Groundwater Well Project and the Otay WD Rosarito Ocean Desalination Facility
project. The Water Authority and MWD next forecast and supply planning documents would
capture any increase in water supplies resulting from verifiable new water resources
developed by the Otay WD.
In addition, MWD’s 2015 UWMP identified potential reserve supplies in the supply
capability analysis (Tables 2-4, 2-5, and 2-6), which could be available to meet any
unanticipated demands. The Water Authority and MWD’s next forecasts and supply planning
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documents would capture any increase in necessary supply resources resulting from any new
water supply resources.
Demand Methodology
The Otay WD water demand projection methodology in the WFMP Update utilizes a
component land use approach. This is done by applying representative values of water use to
the acreage of each land use type and then aggregating these individual land use demand
projections into an overall total demand for the Otay WD. This is called the water duty
method, and the water duty is the amount of water used in gallons per day per acre per year.
This approach is used for all the land use types except residential development where a
demand per dwelling unit was applied. In addition, commercial and industrial water use
categories are further subdivided by type including separate categories for golf courses,
schools, jails, prisons, hospitals, etc. where specific water demands are established.
To determine water duties for the various types of land use, the entire water meter database of
the Otay WD is utilized and sorted by the appropriate land use types. The metered
consumption records are then examined for each of the land uses, and water duties are determined for
the various types of residential, commercial, industrial, and institutional land uses. For example,
the water duty factors for commercial and industrial land uses are estimated using 1,785 and 893
gallons per day per acre (gpd/acre) respectively. Residential water demand is established based on
the same data but computed on a per-dwelling unit basis. The focus is to ensure that for each of the
residential land use categories (very low, low, medium, and high densities), the demand criteria
used is adequately represented based upon actual data. This method is used because
residential land uses constitute a substantial percentage of the total developable planning area of the
Otay WD.
The WFMP Update calculates potable water demand by taking the gross acreage of a site and
applying a potable water reduction factor (PWRF), which is intended to represent the
percentage of acreage to be served by potable water and that not served by recycled water for
irrigation. For industrial land use, as an example, the PWRF is 0.95 (i.e., 95% of the site is
assumed to be served by potable water, 5% of the site is assumed to be irrigated with recycled
water, if available). The potable net acreage is then multiplied by the unit demand factor
corresponding to its respective land use. This approach is used in the WFMP Update for all
the land use types except residential development where a demand per dwelling unit is
applied. In addition, commercial and industrial water use categories are further subdivided by
type including separate categories for golf courses, schools, jails, prisons, hospitals, etc.
where specific water demands are allocated.
Otay Water District Projected Demand
By applying the established water duties to the proposed land uses, the projected water
demand for the entire Otay WD planning area at ultimate development is determined.
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Projected water demands for the intervening years were determined using growth rate
projections consistent with data obtained from SANDAG and the experience of the Otay WD.
The historical and projected potable water demands for Otay WD are shown in Table 1.
Table 1
Historical and Projected Potable Water Fiscal Year Demands (acre-feet)
Water Use Sectors 2010 2015 2020 2025 2030 2035 2040
Single Family 17,165 16,228 17,072 19,806 20,752 20,649 23,224
Multi -Family 3,605 3,460 5,557 6,732 7,342 7,585 8,837
Commercial, Industrial
& Institutional 4,110 4,953 6,577 7,949 8,653 8,923 10,378
Landscape 3,732 4,079 4,400 4,600 4,700 4,900 5,200
AFG* - University I. D. 11.7 11.7 11.7 11.7 11.7
AFG – PA 12 46 46 46 46 46
AFG – Otay 250 836 836 836 836 836
AFG – Sunbow II Phase 84.7 84.7 84.7 84.7
Near-term Annexations 2,973 2,973 2,973 2,973 2,973
Other 2,563 1,578 470 470 470 470 470
Totals 31,175 30,298 37,943 43,508 45,869 46,479 52,060
Source: Otay Water District 2015 UWMP.
*Accelerated Forecasted Growth Increment
Sunbow II, Phase 3 Project Proposed Projected Water Demand
Using the land use demand projection methodology noted above, the projected potable and
recycled water demands for the proposed Sunbow II, Phase 3 project are shown in Table 2
and Table 3, respectively. The projected potable water demand is 122,060 gpd, or about
136.7 ac-ft/yr. The projected recycled water demands for the Sunbow II, Phase 3 project is
24,510 gpd, or about 27.5 AFY.
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Table 2
Sunbow II, Phase 3 Project Projected Potable Water Annual Average Demands
Neighborhood Land Use
Designation
Gross
Acres
Quantity,
Units
Water Duty
Factor
Total Average
Water
Demand, GPD
R-1 MF Residential 8.5 131 170 gpd/unit 22,270
R-2 MF Residential 4.6 73 170 gpd/unit 12,410
R-3 MF Residential 8.1 108 170 gpd/unit 18,360
R-4 MF Residential 8.2 118 170 gpd/unit 20,060
R-5 MF Residential 7.1 104 170 gpd/unit 17,680
R-6 MF Residential 7.6 184 170 gpd/unit 31,280
TOTAL 718 122,060
Table 3
Sunbow II, Phase 3 Project
Projected Recycled Water Demands
Land Use Designation Quantity Irrigation
Factor
Total Average
Demand, GPD
Irrigated Slopes 12 ac 1,900 gpd/ac 22,800
Private Open Space/CPF 0.9 ac 1,900 gpd/ac 1,710
TOTAL 24,510
5.1 Demand Management (Water-Use Efficiency)
Demand management, or water-use efficiency is a critical part of the Otay Water
District’s 2015 Urban Water Management Plan (UWMP) and its long-term strategy for
meeting the water supply needs of its customers. Water conservation is frequently the
lowest cost resource available to any water agency. The Otay WD’s water c onservation
program objectives are to:
•Reduce the demand for more expensive, imported water.
•Ensure a reliable water supply.
The Otay WD was one of the original signatories to the Memorandum of
Understanding (MOU) regarding Urban Water Conservation in California, which
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created the California Urban Water Conservation Council (CUWCC) in 1991 in an
effort to reduce California's long-term water demands. The Otay WD has been a
long-standing supporter of the CUWCC through its implementation of Best
Management Practices (BMPs), which required the District to submit biannual reports
that detailed the implementation of its conservation programs. As a result of the 2014-
2017 drought and the state’s changing regulatory, political, social, economic, and
environmental climate, CUWCC members and its Board, in 2017, restructured the
organization and renamed it the California Water Efficiency Partnership (CWEP).
The new framework allows the organization to better fulfill its members’ needs,
quickly adapt to the changing climate, provide resources about water-use efficiency
issues in California, and foster collaboration among a wide variety of stakeholders.
The Otay WD is currently a member of CWEP as part of its effort to continue
upholding its long-term commitment in reducing the state’s water demands,
diversifying local water supply, and encouraging its customer to make conservation
a way of life. In addition to meeting customer demands during a drought, the District
consistently advocates for state policies and legislation that include supply
development and water-use efficiency. The District continues to work closely with
the Water Authority, the Association of California Water Agencies, and other water
agencies in the region to ensure that the targets and measures in the State Water
Resources Control Board’s (SWRCB) long-term framework support a balanced
approach and reflect local water supply investments and conditions.
Water conservation programs are developed and implemented on the premise that water
conservation increases the local water supply by reducing the demand on available
imported supply, which is vital to the optimal utilization of a region's water supply
resources. The Otay WD participates in many water conservation programs designed
and typically operated on a shared cost-participation program basis among the Water
Authority, MWD, and their member agencies. The demands shown in Tables 1 and 2
take into account implementation of water conservation measures within Otay WD.
As part of the preceding CUWCC’s BMPs requirements, the Otay WD implemented
water conservation programs and provided services to its customers to promote water-use
efficiencies and water savings. It continues to do so today. As a member of the Water
Authority, Otay WD also benefits from regional programs performed on behalf of its
member agencies. In partnership with the Water Authority, the County of San Diego,
City of San Diego, City of Chula Vista, and developers, the Otay WD water-use
efficiency efforts are expected to grow and expand. The resulting savings directly relate
to additional available water in the San Diego County region for beneficial use within
the Water Authority service area, including the Otay WD.
Additional conservation or water-use efficiency measures or programs practiced by the
Otay WD include the following:
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Supervisory Control and Data Acquisition System
The Otay WD implemented and has operated for many years a Supervisory Control and
Data Acquisition (SCADA) system to control, monitor, and collect data regarding the
operation of the water system. The major facilities that have SCADA capabilities are the
water-flow control supply sources, transmission network, pumping stations, and water
storage reservoirs. The SCADA system allows for many and varied useful functions.
Some of the functions they provide for operating personnel are the ability to monitor the
water supply source flow rates, reservoir levels, tum on or off pumping units, etc. The
SCADA system aids in the prevention of water reservoir overflow events and increases
energy efficiency.
Water Conservation Ordinance
California Water Code Sections 375 et seq. permit public entities, which supply retail
water to adopt and enforce a water conservation program to reduce the quantity of
water used by the customers, resulting in the conservation of water supplies for that
public entity. In 1988, the Otay WD Board of Directors established a comprehensive
water conservation program pursuant to California Water Code Sections 375 et seq.,
based upon the need to conserve water supplies and to avoid or minimize the effects of
any future shortage. A water shortage could exist based upon the occurrence of one or
more of the following conditions:
1.A general water supply shortage due to increased demand or limited supplies.
2.Distribution or storage facilities of the Water Authority or other agencies
become inadequate.
3.A major failure of the supply, storage, and distribution facilities of MWD,
Water Authority, and/or Otay WD.
The Otay WD water conservation ordinance specifies that the conditions prevailing in the
San Diego County area require that the available water resources be put to maximum
beneficial use to the extent to which they are capable, and that the waste or unreasonable
use, or unreasonable method of use, of water be prevented. In addition, the ordinance
encourages the conservation of such water with a view to the maximum reasonable and
beneficial use thereof in the interests of the people of the Otay WD and for the public
welfare.
Otay WD continues to promote water-use efficiency and conservation at community
and business events, including those involving developers in its service area. In
addition, Otay WD, working with the Water Authority and MWD manages a number of
programs.
Otay WD is currently engaged in a number of conservation and water-use efficiency
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activities. Listed below are programs that either are current or have been concluded:
•Residential Water Surveys
•Large Landscape Surveys
•Cash for Water Smart Plants Landscape Retrofit Program
•Rotating Nozzles Rebates
•Residential Weather-Based Irrigation Controller (WBIC) Incentive Program
•Residential High Efficiency Clothes Washers
•Residential ULFT/HET Rebate Program
•Outreach Efforts to Otay WD Customers - the Otay WD promotes its
conservation programs through outreach at community and business events, bill
inserts, articles in the Otay WD's quarterly customer Pipeline newsletter, direct
mailings to Otay WD customers, the Otay WD's webpage and social media
platforms, and through the Water Authority's marketing efforts.
•School Education Programs - the Otay WD funds school tours of the Water
Conservation Garden and school assemblies, co-funds Splash Labs, and maintains
school-age appropriate water-themed books, DVDs, and videos.
•Water efficiency in new construction through Cal Green and the Model
Water Efficient Landscape Ordinance
•Focus on Commercial/Institutional/Industrial through Promoting MWD's Save a
Buck (Commercial) Program in conjunction with the Otay WD's own Commercial
Process Improvement Program
•Landscape Contest for homeowners in the Otay WD’s service area
The county’s residents and businesses also exceeded the SWRCB’s emergency water-use
reduction mandates during 2015 and 2016, and they continue to use less water than they
did in 2013 even though drought conditions have ended. Since the SWRCB’s conservation
mandate began in June 2015, Otay customers have saved an average of 14 percent more
water compared to 2013 water-use totals.
Section 6 - Existing and Projected Supplies
The Otay WD currently does not have an independent raw or potable water supply source.
The Otay WD is a member public agency of the Water Authority and the Water Authority is a
member public agency of MWD. The statutory relationships between the Water Authority
and its member agencies, and MWD and its member agencies, respectively, establish the
scope of the Otay WD entitlement to water from these two agencies.
The Water Authority currently supplied the Otay WD with 100 percent of its potable water
through two delivery pipelines, referred to as Pipeline No. 4 and the Helix Flume Pipeline.
The Water Authority in turn, currently purchases the majority of its water from MWD. Due
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to the Otay WD reliance on these two agencies, this WSA&V Report includes referenced
documents that contain information on the existing and projected supplies, supply programs,
and related projects of the Water Authority and MWD. The Otay WD, Water Authority, and
MWD are actively pursuing programs and projects to further diversify their water supply
resources.
The description of local recycled water supplies available to the Otay WD is also discussed
below.
6.1 Metropolitan Water District of Southern California 2015 Urban
Water Management Plan
MWD has prepared its 2015 UWMP which was adopted on May 9, 2016. The 2015 UWMP
provides MWD’s member agencies, retail water utilities, cities, and counties within its service
area with, among other things, a detailed evaluation of the supplies necessary to meet future
demands, and an evaluation of reasonable and practical efficient water uses, recycling, and
conservation activities. During the preparation of the 2015 UWMP, MWD utilized the
previous SANDAG regional growth forecast in calculating regional water demands for the
Water Authority service area.
6.1.1 Availability of Sufficient Supplies and Plans for Acquiring
Additional Supplies
MWD is a wholesale supplier of water to its member public agencies and obtains its supplies
from two primary sources: the Colorado River, via the Colorado River Aqueduct (CRA),
which it owns and operates, and Northern California, via the State Water Project (SWP). The
2015 UWMP documents the availability of these existing supplies and additional supplies
necessary to meet future demands.
MWD’s IRP identifies a mix of resources (imported and local) that, when implemented, will
provide 100 percent reliability for full-service demands through the attainment of regional
targets set for conservation, local supplies, State Water Project supplies, Colorado River
supplies, groundwater banking, and water transfers. The 2015 update to the IRP (2015 IRP
Update) describes an adaptive management strategy to protect the region from future supply
shortages. This adaptive management strategy has five components: achieve additional
conservation savings, develop additional local water supplies, maintain Colorado River
Aqueduct supplies, stabilize State Water Project supplies, and maximize the effectiveness of
storage and transfer. MWD’s 2015 IRP Update has a plan for identifying and implementing
additional resources that expand the ability for MWD to meet future changes and challenges
as necessary to ensure future reliability of supplies. The proper management of these
resources help to ensure that the southern California region, including San Diego County, will
have adequate water supplies to meet long-term future demands.
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In May 2016, MWD adopted its 2015 UWMP in accordance with state law. The resource
targets included in the preceding 2015 IRP Update serve as the foundation for the planning
assumptions used in the 2015 UWMP. MWD’s 2015 UWMP contains a water supply
reliability assessment that includes a detailed evaluation of the supplies necessary to meet
demands over a 20-year period in average, single dry year, and multiple dry year periods. As
part of this process, MWD also uses the current SANDAG regional growth forecast in
calculating regional water demands for the Water Authority’s service area.
As stated in MWD’s 2015 UWMP, the plan may be used as a source document for meeting
the requirements of SB 610 and SB 221 until the next scheduled update is completed in 5
years (2020). The 2015 UWMP includes a “Justifications for Supply Projections” in
Appendix A.3, that provides detailed documentation of the planning, legal, financial, and
regulatory basis for including each source of supply in the plan. A copy of MWD’s 2015
UWMP can be found on the internet at the following site address:
http://www.mwdh2o.com/PDF_About_Your_Water/2015_UWMP.pdf
The UWMP updates for both MWD and the Water Authority included the increase in demand
projections included in SANDAG’s Series 13 Update and from the projections from Otay
Water District WFMP Update.
Water supply agencies throughout California continue to face climate, environmental, legal,
and other challenges that impact water source supply conditions, such as the court rulings
regarding the Sacramento-San Joaquin Delta and the current western states drought
conditions. Challenges such as these essentially always will be present. The regional water
supply agencies, the Water Authority and MWD, along with Otay WD nevertheless fully
intend to have sufficient, reliable supplies to serve demands.
6.1.2 MWD Capital Investment Plan
MWD prepares a Capital Investment Plan as part of its annual budget approval process. The
cost, purpose, justification, status, progress, etc. of MWD’s infrastructure projects to deliver
existing and future supplies are documented in the Capital Investment Plan. The financing of
these projects is addressed as part of the annual budget approval process.
MWD’s Capital Investment Plan includes a series of projects identified from MWD studies of
projected water needs, which, when considered along with operational demands on aging
facilities and new water quality regulations, identify the capital projects needed to maintain
infrastructure reliability and water quality standards, improve efficiency, and provide future
cost savings. All projects within the Capital Investment Plan are evaluated against an
objective set of criteria to ensure they are aligned with the MWD’s goals of supply reliability
and quality.
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6.2 San Diego County Water Authority Regional Water Supplies
The Water Authority has adopted plans and is taking specific actions to develop adequate
water supplies to help meet existing and future water demands within the San Diego region.
This section contains details on the supplies being developed by the Water Authority. A
summary of recent actions pertaining to development of these supplies includes:
In accordance with the Urban Water Management Planning Act, the Water Authority
adopted their 2015 UWMP in June 2016. The updated Water Authority 2015 UWMP
identifies a diverse mix of local and imported water supplies to meet future demands. A
copy of the updated Water Authority 2015 UWMP can be found on the internet at:
http://www.sdcwa.org/sites/default/files/UWMP2015.pdf
As part of the October 2003 Colorado River Quantification Settlement Agreement
(QSA), the Water Authority was assigned MWD’s rights to 77,700 acre feet per year of
conserved water from the All-American Canal (AAC) and Coachella Canal (CC) lining
projects. Deliveries of this conserved water from the CC reached the region in 2007 and
deliveries from the AAC reached the region in 2010. Expected supplies from the canal
lining projects are considered verifiable Water Authority supplies.
Deliveries of conserved agricultural water from the Imperial Irrigation District (IID) to
San Diego County have increased annually since 2003, with 70,000 acre-feet per year of
deliveries in Fiscal Year (FY) 2010. The quantities will increase annually to 200,000
acre-feet per year by 2021, and then remain fixed for the duration of the transfer
agreement.
Development of seawater desalination in San Diego County assists the region in
diversifying its water resources; reduces dependence on imported supplies; and provides
a new drought‐proof, locally treated water supply. The Carlsbad Desalination Project is
a fully operational seawater desalination plant and conveyance pipeline developed by
Poseidon, a private investor–owned company that develops water and wastewater
infrastructure. The Carlsbad Desalination Project, located near the Carlsbad Energy
Center, began commercial operation on December 23, 2015, and can provide a highly
reliable local supply of up to 56,000 AF/YR for the region. Of the total Carlsbad
Desalination Plant production, Vallecitos Water District has a direct connection and a
contract to receive 4,083 AFY. Carlsbad MWD has agreed to a take or pay of 2,500
AFY.
Through implementation of the Water Authority and member agency planned supply projects,
along with reliable imported water supplies from MWD, the region anticipates having
adequate supplies to meet existing and future water demands.
To ensure sufficient supplies to meet projected growth in the San Diego region, the Water
Authority uses the SANDAG most recent regional growth forecast in calculating regional
water demands. The SANDAG regional growth forecast is based on the plans and policies of
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the land-use jurisdictions with San Diego County. The existing and future demands of the
member agencies are included in the Water Authority’s projections.
6.2.1 Availability of Sufficient Supplies and Plans for Acquiring
Additional Supplies
The Water Authority currently obtains imported supplies from MWD, conserved water from
the AAC and CC lining projects, an increasing amount of conserved agricultural water from
IID, and desalinated seawater from the Carlsbad desalination plant. Of the twenty-seven
member agencies that purchase water supplies from MWD, the Water Authority is MWD ’s
largest customer.
Section 135 of MWD’s Act defines the preferential right to water for each of its member
agencies. Currently, the Water Authority pays about 22 percent of MWD's total revenue, but
has preferential rights to only 18.27 percent of MWD's water supply. Under preferential
rights, MWD could allocate water without regard to historic water purchases or dependence
on MWD. The Water Authority and its member agencies are taking measures to reduce
dependence on MWD through development of additional supplies and a water supply
portfolio that would not be jeopardized by a preferential rights allocation. MWD has stated,
consistent with Section 4202 of its Administrative Code that it is prepared to provide the
Water Authority’s service area with adequate supplies of water to meet expanding and
increasing needs in the years ahead. When and as additional water resources are required to
meet increasing needs, MWD stated it will be prepared to deliver such supplies. In Section
ES-5 of their 2015 UWMP, MWD states that MWD has supply capacities that would be
sufficient to meet expected demands from 2020 through 2040. MWD has plans for supply
implementation and continued development of a diversified resource mix including programs
in the Colorado River Aqueduct, State Water Project, Central Valley Transfers, local resource
projects, and in-region storage that enables the region to meet its water supply needs.
The Water Authority has made large investments in MWD’s facilities and will continue to
include imported supplies from MWD in the future resource mix. As discussed in the Water
Authority’s 2015 UWMP, the Water Authority and its member agencies are planning to
diversify the San Diego regions supply portfolio and reduce purchases from MWD.
As part of the Water Authority’s diversification efforts, the Water Authority is now taking
delivery of conserved agricultural water from IID, water saved from the AAC and CC lining
projects and desalinated seawater from the Carlsbad desalination plant. Table 4 summarizes
the Water Authority’s supply sources with detailed information included in the sections to
follow. Deliveries from MWD are also included in Table 4, which is further discussed in
Section 6.1 above. The Water Authority’s member agencies provided the verifiable local
supply targets for groundwater, recycled water, potable reuse and surface water, which are
discussed in more detail in Section 5 of the Water Authority’s 2015 UWMP.
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Table 4
Projected Verifiable Water Supplies – Water Authority Service Area
Normal Year (acre feet)1
Water Supply Sources 2020 2025 2030 2035 2040
Water Authority Supplies
MWD Supplies 136,002 181,840 207,413 224,863 248,565
Water Authority/IID Transfer 190,000 200,000 200,000 200,000 200,000
AAC and CC Lining Projects 80,200 80,200 80,200 80,200 80,200
Regional Seawater Desalination 50,000 50,000 50,000 50,000 50,000
Member Agency Supplies
Surface Water 51,580 51,480 51,380 51,280 51,180
Water Recycling 40,459 43,674 45,758 46,118 46,858
Seawater Desalination 6,000 6,000 6,000 6,000 6,000
Brackish GW Recovery 12,100 12,500 12,500 12,500 12,500
Groundwater 17,940 19,130 20,170 20,170 20,170
Potable Reuse 3,300 3,300 3,300 3,300 3,300
Total Projected Supplies 587,581 648,124 676,721 694,431 718,773
Source: Water Authority 2015 Urban Water Management Plan – Table 9-1.
1Normal water year demands based on 1960-2013 hydrology.
Section 5.6.1 of the Water Authority’s 2015 UWMP also includes a discussion on the local
supply target for seawater desalination. Seawater desalination supplies represent a significant
local resource in the Water Authority’s service area.
The Carlsbad Desalination Project (Project) is a fully-permitted seawater desalination plant
and conveyance pipeline designed to provide a highly reliable local supply of up to 56,000
acre-feet (AF) per year for the region. In 2020, the Project would account for approximately
8% of the total projected regional supply and 30% of all locally generated water in San Diego
County. The project became operational in late 2015 and it more than doubles the amount of
local supplies developed in the region since 1991. The desalination plant itself was fully
financed, built, by Poseidon Resources (Channelside) LC. The equity owner of the plant,
Orion Water Partners LLC, entered into an agreement to sell its ownership to Aberdeen
Standard Investments. Poseidon Water LLC is the Project Manager to perform the
management and administrative functions at the plant for the new owner. The Water
Authority purchases water from the plant under a water purchase agreement. The new
pipeline connecting the desalination plant with the Water Authority’s Second Aqueduct is
owned and operated by the Water Authority, but Poseidon had the responsibility for design
and construction through a separate Design-Build Agreement. The Water Authority was
responsible for aqueduct improvements, including the relining and rehabilitation of Pipeline 3
to accept desalinated water under higher operating pressures, modifications to the San Marcos
Vent that allows the flow of water between Pipelines 3 and 4, and improvements at the Twin
Oaks Valley Water Treatment Plant necessary to integrate desalinated water into the Water
Authority’s system for optimal distribution to member agencies.
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The Water Authority’s existing and planned supplies from the IID transfer, canal lining, and
desalination projects are considered “drought-proof” supplies and should be available at the
yields shown in Table 4 in normal water year supply and demand assessment. Single dry year
and multiple dry year scenarios are discussed in more detail in Section 9 of the Water
Authority’s 2015 UWMP.
As part of preparation of a written water supply assessment and/or verification report, an
agency’s shortage contingency analysis should be considered in determining sufficiency of
supply. Section 11 of the Water Authority’s 2015 UWMP contains a detailed shortage
contingency analysis that addresses a regional catastrophic shortage situation and drought
management. The analysis demonstrates that the Water Authority and its member agencies,
through the Integrated Contingency Plan, Emergency Storage Project, and Water Shortage
Contingency Plan are taking actions to prepare for and appropriately handle an interruption of
water supplies. The Water Authority’s Board of Directors approved the Drought Management
Plan (DMP) in 2006. The DMP outlined a series of orderly, progressive steps for the Water
Authority and its member agencies to take during shortages to minimize impacts to the
region’s economy and quality of life. It also included an allocation methodology to equitably
allocate water supplies to the member agencies. The DMP was first activated in 2007 in
response to MWD drawing water from storage to meet demands, and deactivated in 2011
when supply conditions improved.
In 2008, the Water Authority’s Board approved another drought management document, the
Model Drought Response Conservation Program Ordinance. The model ordinance focuses on
core water use restrictions and is intended to assist the member agencies when updating or
drafting local drought response ordinances. The intent of the model ordinance is to provide
regional consistency in drought response levels and messaging to the public and media. Also
in 2008, the Water Authority’s Board adopted Resolution 2008-11, that established
procedures to administer the supply allocation methodology contained in the DMP.
In 2012, the DMP’s supply allocation methodology was updated, using lessons from the
previous shortage periods, and the DMP was renamed the Water Shortage and Drought
Response Plan (WSDRP). In 2014, the WSDRP was activated due to critically dry weather in
California and the impact on water supply conditions. It deactivated in 2016 when supply
conditions improved.
In each instance when the DMP and WSDRP were activated, a smooth transition into and out
of water allocations for the member agencies was possible due to the advanced planning of
the Water Authority and its member agencies. Those planning efforts also resulted in an
approach that allowed for regional consistency in public drought messaging.
On August 24, 2017, the Water Authority’s Board approved proposed revisions of the
WSDRP and renamed it the Water Shortage Contingency Plan (WSCP) to align the WSCP
with the framework outlined in the April 2017 Final Report, Making Water Conservation a
California Way of Life, Implementing Executive Order B-37-16 in the areas of water use
efficiency and shortage response planning. The WSCP continues a proactive and
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comprehensive approach to shortage response planning for the region. The plan will be
reviewed and potentially updated at least every five years in coordination with the preparation
of the Water Authority’s Urban Water Management Plan for 2020, which will include any
final requirements approved through legislation implementing the state’s framework report.
The approval of the WSCP does not require the member agencies to update their planning
document or conservation ordinance at this time.
6.2.1.1 Water Authority-Imperial Irrigation District Water Conservation
and Transfer Agreement
The QSA was signed in October 2003, and resolves long-standing disputes regarding priority
and use of Colorado River water and creates a baseline for implementing water transfers. With
approval of the QSA, the Water Authority and IID were able to implement their Water
Conservation and Transfer Agreement. This agreement not only provides reliability for the San
Diego region, but also assists California in reducing its use of Colorado River water to its legal
allocation.
On April 29, 1998, the Water Authority signed a historic agreement with IID for the long-term
transfer of conserved Colorado River water to San Diego County. The Water Authority-IID
Water Conservation and Transfer Agreement (Transfer Agreement) is the largest agriculture-to-
urban water transfer in United States history. Colorado River water will be conserved by
Imperial Valley farmers who voluntarily participate in the program and then transferred to the
Water Authority for use in San Diego County.
Implementation Status
On October 10, 2003, the Water Authority and IID executed an amendment to the original 1998
Transfer Agreement. This amendment modified certain aspects of the Transfer Agreement to be
consistent with the terms and conditions of the QSA and related agreements. It also modified
other aspects of the agreement to lessen the environmental impacts of the transfer of conserved
water. The amendment was expressly contingent on the approval and implementation of the
QSA, which was also executed on October 10, 2003. Section 6.2.1, “Colorado River,” contains
details on the QSA.
On November 5, 2003, IID filed a complaint in Imperial County Superior Court seeking
validation of 13 contracts associated with the Transfer Agreement and the QSA. Imperial
County and various private parties filed additional suits in Superior Court, alleging violations of
the California Environmental Quality Act (CEQA), the California Water Code, and other laws
related to the approval of the QSA, the water transfer, and related agreements. The lawsuits were
coordinated for trial. The IID, Coachella Valley Water District, MWD, the Water Authority, and
state are defending these suits and coordinating to seek validation of the contracts. In January
2010, a California Superior Court judge ruled that the QSA and 11 related agreements were
invalid, because one of the agreements created an open-ended financial obligation for the state,
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in violation of California’s constitution. The QSA parties appealed this decision and on July
2013, a Sacramento Superior Court judge entered a final judgment validating the QSA and
rejecting all of the remaining legal challenges. The judge affirmed all of the contested actions,
including the adequacy of the environmental documents prepared by the IID. In May 2015, the
state Court of Appeal issued a ruling that dismissed all remaining appeals.
Expected Supply
Deliveries into San Diego County from the transfer began in 2003 with an initial transfer of
10,000 acre-feet per year. The Water Authority received increasing amounts of transfer water
each year, according to a water delivery schedule contained in the transfer agreement The
quantities will increase annually to 200,000 acre feet per year by 2021 then remain fixed for the
duration of the transfer agreement. The initial term of the Transfer Agreement is 45 years, with a
provision that either agency may extend the agreement for an additional 30-year term.
During dry years, when water availability is low, the conserved water will be transferred
under IID’s Colorado River rights, which are among the most senior in the Lower Colorado
River Basin. Without the protection of these rights, the Water Authority could suffer delivery
cutbacks. In recognition for the value of such reliability, the 1998 contract required the Water
Authority to pay a premium on transfer water under defined regional shortage circumstances.
The shortage premium period duration is the period of consecutive days during which any of the
following exist: 1) a Water Authority shortage; 2) a shortage condition for the Lower Colorado
River as declared by the Secretary; and 3) a Critical Year. Under terms of the October 2003
amendment, the shortage premium will not be included in the cost formula until Agreement Year
16.
Transportation
The Water Authority entered into a water exchange agreement with MWD on October 10, 2003,
to transport the Water Authority–IID transfer water from the Colorado River to San Diego
County. Under the exchange agreement, MWD takes delivery of the transfer water through its
Colorado River Aqueduct. In exchange, MWD delivers to the Water Authority a like quantity
and quality of water. The Water Authority pays MWD’s applicable wheeling rate for each acre-
feet of exchange water delivered. Under the terms of the water exchange agreement, MWD will
make delivery of the transfer water for 35 years, unless the Water Authority and MWD elect to
extend the agreement another 10 years for a total of 45 years.
Cost/Financing
The costs associated with the transfer are financed through the Water Authority’s rates and
charges. In the agreement between the Water Authority and IID, the price for the transfer water
started at $258 per acre-feet and increased by a set amount for the first seven years. In December
2009, the Water Authority and IID executed a fifth amendment to the water transfer agreement
that sets the price per acre-feet for transfer water for calendar years 2010 through 2015,
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beginning at $405 per acre-feet in 2010 and increasing to $624 per acre-feet in 2015. For
calendar years 2016 through 2034, the unit price will be adjusted using an agreed-upon index.
The amendment also required the Water Authority to pay IID $6 million at the end of calendar
year 2009 and another $50 million on or before October 1, 2010, provided that a transfer
stoppage is not in effect as a result of a court order in the QSA coordinated cases. Beginning in
2035, either the Water Authority or IID can, if certain criteria are met, elect a market rate price
through a formula described in the water transfer agreement.
The October 2003 exchange agreement between MWD and the Water Authority set the initial
cost to transport the conserved water at $253 per acre-feet. Thereafter, the price is set to be equal
to the charge or charges set by MWD’s Board of Directors pursuant to applicable laws and
regulation, and generally applicable to the conveyance of water by MWD on behalf of its
member agencies.
The Water Authority is providing $10 million to help offset potential socioeconomic impacts
associated with temporary land fallowing. IID will credit the Water Authority for these funds
during years 16 through 45. In 2007, the Water Authority prepaid IID an additional $10 million
for future deliveries of water. IID will credit the Water Authority for this up-front payment
during years 16 through 30.
As part of implementation of the QSA and water transfer, the Water Authority also entered into
an environmental cost sharing agreement. Under this agreement the Water Authority is
contributing a total of $64 million to fund environmental mitigation projects and the Salton Sea
Restoration Fund.
Written Contracts or Other Proof
The supply and costs associated with the transfer are based primarily on the following
documents:
Agreement for Transfer of Conserved Water by and between IID and the Water Authority (April
29, 1998). This Agreement provides for a market-based transaction in which the Water
Authority would pay IID a unit price for agricultural water conserved by IID and transferred to
the Water Authority.
Revised Fourth Amendment to Agreement between IID and the Water Authority for Transfer of
Conserved Water (October 10, 2003). Consistent with the executed Quantification Settlement
Agreement (QSA) and related agreements, the amendments restructure the agreement and
modify it to minimize the environmental impacts of the transfer of conserved water to the Water
Authority.
Amended and Restated Agreement between MWD and Water Authority for the Exchange of
Water (October 10, 2003). This agreement was executed pursuant to the QSA and provides for
delivery of the transfer water to the Water Authority.
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Environmental Cost Sharing, Funding, and Habitat Conservation Plan Development Agreement
among IID, Coachella Valley Water District (CVWD), and Water Authority (October 10, 2003).
This Agreement provides for the specified allocation of QSA-related environmental review,
mitigation, and litigation costs for the term of the QSA, and for development of a Habitat
Conservation Plan.
Quantification Settlement Agreement Joint Powers Authority Creation and Funding Agreement
(October 10, 2003). The purpose of this agreement is to create and fund the QSA Joint Powers
Authority and to establish the limits of the funding obligation of CVWD, IID, and Water
Authority for environmental mitigation and Salton Sea restoration pursuant to SB 654
(Machado).
Fifth Amendment to Agreement Between Imperial Irrigation District and San Diego County
Water Authority for Transfer of Conserved Water (December 21, 2009). This agreement
implements a settlement between the Water Authority and IID regarding the base contract price
of transferred water.
Federal, State, and Local Permits/Approvals
Federal Endangered Species Act Permit. The U.S. Fish and Wildlife Service (USFWS) issued a
Biological Opinion on January 12, 2001, that provides incidental take authorization and certain
measures required to offset species impacts on the Colorado River regarding such actions.
State Water Resources Control Board (SWRCB) Petition. SWRCB adopted Water Rights Order
2002-0016 concerning IID and Water Authority’s amended joint petition for approval of a long-
term transfer of conserved water from IID to the Water Authority and to change the point of
diversion, place of use, and purpose of use under Permit 7643.
Environmental Impact Report (EIR) for Conservation and Transfer Agreement. As lead agency,
IID certified the Final EIR for the Conservation and Transfer Agreement on June 28, 2002.
U. S. Fish and Wildlife Service Draft Biological Opinion and Incidental Take Statement on the
Bureau of Reclamation's Voluntary Fish and Wildlife Conservation Measures and Associated
Conservation Agreements with the California Water Agencies (12/18/02). The U. S. Fish and
Wildlife Service issued the biological opinion/incidental take statement for water transfer
activities involving the Bureau of Reclamation and associated with IID/other California water
agencies' actions on listed species in the Imperial Valley and Salton Sea (per the June 28, 2002
EIR).
Addendum to EIR for Conservation and Transfer Agreement. IID as lead agency and Water
Authority as responsible agency approved addendum to EIR in October 2003.
Environmental Impact Statement (EIS) for Conservation and Transfer Agreement. Bureau of
Reclamation issued a Record of Decision on the EIS in October 2003.
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CA Department of Fish and Game California Endangered Species Act Incidental Take Permit
#2081-2003-024-006). The California Department of Fish and Game issued this permit
(10/22/04) for potential take effects on state-listed/fully protected species associated with
IID/other California water agencies' actions on listed species in the Imperial Valley and Salton
Sea (per the June 28, 2002 EIR).
California Endangered Species Act (CESA) Permit. A CESA permit was issued by California
Department of Fish and Game (CDFG) on April 4, 2005, providing incidental take authorization
for potential species impacts on the Colorado River.
6.2.1.2 All-American Canal and Coachella Canal Lining Projects
As part of the QSA and related contracts, the Water Authority was assigned MWD’s rights to
77,700 acre-feet per year of conserved water from projects that will line the All-American
Canal (AAC) and Coachella Canal (CC). The projects will reduce the loss of water that
currently occurs through seepage, and the conserved water will be delivered to the Water
Authority. This conserved water will provide the San Diego region with an additional 8.5
million acre-feet over the 110-year life of the agreement.
Implementation Status
The CC lining project began in November 2004 and was completed in 2006. Deliveries of
conserved water to the Water Authority began in 2007. The project constructed a 37-mile
parallel canal adjacent to the CC. The AAC lining project was begun in 2005 and was
completed in 2010. The lining project constructed a concrete-lined canal parallel to 24 miles
of the existing AAC from Pilot Knob to Drop 3.
In July 2005, a lawsuit (CDEM v United States, Case No. CV-S-05-0870-KJD-PAL) was filed
in the U. S. District Court for the District of Nevada on behalf of U.S. and Mexican groups
challenging the lining of the AAC. The lawsuit, which names the Secretary of the Interior as
a defendant, claims that seepage water from the canal belongs to water users in Mexico.
California water agencies note that the seepage water is actually part of California's Colorado
River allocation and not part of Mexico's allocation. The plaintiffs also allege a failure by the
United States to comply with environmental laws. Federal officials have stated that they
intend to vigorously defend the case.
Expected Supply
The AAC lining project makes 67,700 acre-feet of Colorado River water per year available
for allocation to the Water Authority and San Luis Rey Indian water rights settlement parties.
The CC lining project makes 26,000 acre-feet of Colorado River water each year available for
allocation. The 2003 Allocation Agreement provides for 16,000 acre-feet per year of
conserved canal lining water to be allocated to the San Luis Rey Indian Water Rights
Settlement Parties. The remaining amount, 77,700 acre-feet per year, is to be available to the
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Water Authority, with up to an additional 4,850 acre-feet per year available to the Water
Authority depending on environmental requirements from the CC lining project. For planning
purposes, the Water Authority assumes that 2,500 acre-feet of the 4,850 acre-feet will be
available each year for delivery, for a total of 80,200 acre-feet per year of that supply.
According to the Allocation Agreement, IID has call rights to a portion (5,000 acre-feet per
year) of the conserved water upon termination of the QSA for the remainder of the 110 years
of the Allocation Agreement and upon satisfying certain conditions. The term of the QSA is
for up to 75 years.
Transportation
The October 2003 Exchange Agreement between the Water Authority and MWD provides for
the delivery of the conserved water from the canal lining projects. The Water Authority pays
MWD’s applicable wheeling rate for each acre-foot of exchange water delivered. In the
Agreement, MWD will deliver the canal lining water for the term of the Allocation
Agreement (110 years).
Cost/Financing
Under California Water Code Section 12560 et seq., the Water Authority received $200
million in state funds for construction of the canal lining projects. In addition, $20 million
was made available from Proposition 50 and $36 million from Proposition 84. The Water
Authority was responsible for additional expenses above the funds provided by the state.
The rate to be paid to transport the canal lining water will be equal to the charge or charges set
by MWD’s Board of Directors pursuant to applicable law and regulation and generally
applicable to the conveyance of water by MWD on behalf of its member agencies.
In accordance with the Allocation Agreement, the Water Authority is responsible for a portion
of the net additional Operation, Maintenance, and Repair (OM&R) costs for the lined canals.
Any costs associated with the lining projects as proposed are to be financed through the Water
Authority’s rates and charges.
Written Contracts or Other Proof
The expected supply and costs associated with the lining projects are based primarily on the
following documents:
U.S. Public Law 100-675 (1988). Authorized the Department of the Interior to reduce seepage
from the existing earthen AAC and CC. The law provides that conserved water will be made
available to specified California contracting water agencies according to established priorities.
California Department of Water Resources - MWD Funding Agreement (2001). Reimburse
MWD for project work necessary to construct the lining of the CC in an amount not to exceed
$74 million. Modified by First Amendment (2004) to replace MWD with the Authority.
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Modified by Second Amendment (2004) to increase funding amount to $83.65 million, with
addition of funds from Proposition 50.
California Department of Water Resources - IID Funding Agreement (2001). Reimburse IID for
project work necessary to construct a lined AAC in an amount not to exceed $126 million.
MWD - CVWD Assignment and Delegation of Design Obligations Agreement (2002). Assigns
design of the CC lining project to CVWD.
MWD - CVWD Financial Arrangements Agreement for Design Obligations (2002). Obligates
MWD to advance funds to CVWD to cover costs for CC lining project design and CVWD to
invoice MWD to permit the Department of Water Resources to be billed for work completed.
Allocation Agreement among the United States of America, The MWD Water District of
Southern California, Coachella Valley Water District, Imperial Irrigation District, San Diego
County Water Authority, the La Jolla, Pala, Pauma, Rincon, and San Pasqual Bands of Mission
Indians, the San Luis Rey River Indian Water Authority, the City of Escondido, and Vista
Irrigation District (October 10, 2003). This agreement includes assignment of MWD’s rights
and interest in delivery of 77,700 acre-feet of Colorado River water previously intended to be
delivered to MWD to the Water Authority. Allocates water from the AAC and CC lining
projects for at least 110 years to the Water Authority, the San Luis Rey Indian Water Rights
Settlement Parties, and IID, if it exercises its call rights.
Amended and Restated Agreement between MWD and Water Authority for the Exchange of
Water (October 10, 2003). This agreement was executed pursuant to the QSA and provides for
delivery of the conserved canal lining water to the Water Authority.
Agreement between MWD and Water Authority regarding Assignment of Agreements related to
the AAC and CC Lining Projects. This agreement was executed in April 2004 and assigns
MWD's rights to the Water Authority for agreements that had been executed to facilitate funding
and construction of the AAC and CC lining projects:
Assignment and Delegation of Construction Obligations for the Coachella Canal Lining Project
under the Department of Water Resources Funding Agreement No. 4600001474 from the San
Diego County Water Authority to the Coachella Valley Water District, dated September 8, 2004.
Agreement Regarding the Financial Arrangements between the San Diego County Water
Authority and Coachella Valley Water District for the Construction Obligations for the
Coachella Canal Lining Project, dated September 8, 2004.
Agreement No. 04-XX-30-W0429 Among the United States Bureau of Reclamation, the
Coachella Valley Water District, and the San Diego County Water Authority for the
Construction of the Coachella Canal Lining Project Pursuant to Title II of Public Law 100-675,
dated October 19, 2004.
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California Water Code Section 12560 et seq. This Water Code Section provides for $200
million to be appropriated to the Department of Water Resources to help fund the canal lining
projects in furtherance of implementing California’s Colorado River Water Use Plan.
California Water Code Section 79567. This Water Code Section identifies $20 million as
available for appropriation by the California Legislature from the Water Security, Clean
Drinking Water, Coastal, and Beach Protection Fund of 2002 (Proposition 50) to DWR for
grants for canal lining and related projects necessary to reduce Colorado River water use.
According to the Allocation Agreement, it is the intention of the agencies that those funds will be
available for use by the Water Authority, IID, or CVWD for the AAC and CC lining projects.
California Public Resources Code Section 75050(b) (1). This section identifies up to $36 million
as available for water conservation projects that implement the Allocation Agreement as defined
in the Quantification Settlement Agreement.
Federal, State, and Local Permits/Approvals
AAC Lining Project Final EIS/EIR (March 1994). A final EIR/EIS analyzing the potential
impacts of lining the AAC was completed by the Bureau of Reclamation (Reclamation) in March
1994. A Record of Decision was signed by Reclamation in July 1994, implementing the
preferred alternative for lining the AAC. A re-examination and analysis of these environmental
compliance documents by Reclamation in November 1999 determined that these documents
continued to meet the requirements of the NEPA and the CEQA and would be valid in the future.
CC Lining Project Final EIS/EIR (April 2001). The final EIR/EIS for the CC lining project was
completed in 2001. Reclamation signed the Record of Decision in April 2002. An amended
Record of Decision has also been signed to take into account revisions to the project description.
Mitigation, Monitoring, and Reporting Program for Coachella Canal Lining Project, SCH
#1990020408; prepared by Coachella Valley Water District, May 16, 2001.
Environmental Commitment Plan for the Coachella Canal Lining Project, approved by the US
Bureau of Reclamation (Boulder City, NV) on March 4, 2003.
Environmental Commitment Plan and Addendum to the All-American Canal Lining Project
EIS/EIR California State Clearinghouse Number SCH 90010472 (June 2004, prepared by
IID).
Addendum to Final EIS/EIR and Amendment to Environmental Commitment Plan for the
All-American Canal Lining Project (approved June 27, 2006, by IID Board of Directors).
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6.2.1.3 Carlsbad Seawater Desalination Project
Development of seawater desalination in San Diego County has assisted the region in
diversifying its water resources, reduce dependence on imported supplies, and provide a new
drought-proof, locally treated water supply. The Carlsbad Desalination Project is a fully-
permitted seawater desalination plant and conveyance pipeline developed by Poseidon, a
private investor–owned company that develops water and wastewater infrastructure. The
project, located near the Carlsbad Energy Center, has been in development since 1998 and
was incorporated into the Water Authority’s 2003 Water Facilities Master Plan and the 2015
UWMP. The Carlsbad Desalination Project has obtained all required permits and
environmental clearances and starting in late 2015 provides a highly reliable local supply of
48,000 to 56,000 acre-feet per year for the region.
Implementation Status
The Project obtained all required permits and environmental clearances, including the
following:
National Pollutant Discharge Elimination System (NPDES) Discharge Permit
(Regional Water Quality Control Board)
Conditional Drinking Water Permit (California Department of Health Services)
State Lands Commission Lease (State Lands Commission)
Coastal Development Permit (California Coastal Commission)
IDE Technologies, a worldwide leader in the design, construction, and operation of
desalination plants, was the desalination process contractor for the Project.
On July 22, 2010, the Board approved a Term Sheet between the Water Authority and
Poseidon Resources that outlined the key terms and conditions that would be detailed and
incorporated in a comprehensive Water Purchase Agreement (WPA). Beginning in October
2011 and under the direction of the Board’s Carlsbad Desalination Project Advisory Group,
staff began developing and negotiating with Poseidon a WPA consistent with the July 22,
2010 Board approved Term Sheet. The July 2010 Term Sheet also identified specific
conditions precedent to Board consideration of the WPA.
On November 29, 2012, the Water Authority Board adopted a resolution approving the
Design-Build Agreement between the Water Authority and Poseidon. The Design-Build
Agreement established the commercial and technical terms for implementation of the
desalination product pipeline improvements. These improvements consisted of an
approximate 10-mile long, 54-inch diameter conveyance pipeline connecting the Desalination
Plant to the Water Authority’s Second Aqueduct. The pipeline was generally be constructed
within improved streets in commercial and industrial areas in the cities of Carlsbad, Vista, and
San Marcos. The Water Authority owns the Project Water Pipeline Improvements and has
assumed operational control of all pipeline improvements. This system was placed into
service in late 2015.
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Expected Supply
The Project provides a highly reliable local supply of 48,000 to 56,000 acre-feet per year of
supply for the region, available in both normal and dry hydrologic conditions. In 2020, the
Project would account for approximately 8% of the total projected regional supply and 30%
of all locally generated water in San Diego County. The project more than doubles the
amount of local supplies developed in the region since 1991.
Transportation
On November 29, 2012, the Water Authority Board adopted a resolution approving the
Design-Build Agreement between the Water Authority and Poseidon. The Design-Build
Agreement establishes the commercial and technical terms for implementation of the
desalination product pipeline improvements. These improvements consisted of an
approximate 10-mile long, 54-inch diameter conveyance pipeline connecting the Desalination
Plant to the Water Authority’s Second Aqueduct. The pipeline was generally constructed
within improved streets in commercial and industrial areas in the cities of Carlsbad, Vista, and
San Marcos. The Water Authority owns the Project Water Pipeline Improvements and has
assumed operational control of all pipeline improvements.
The Water Authority was responsible for aqueduct improvements, including the relining and
rehabilitation of Pipeline 3 to accept desalinated water under higher operating pressures,
modifications to the San Marcos Vent that allows the flow of water between Pipelines 3 and
4, and improvements at the Twin Oaks Valley Water Treatment Plant necessary to integrate
desalinated water into the Water Authority’s system for optimal distribution to member
agencies.
Cost/Financing
The plant and the offsite pipeline is being financed through tax exempt government bonds
issued for the Water Authority by the California Pollution Control Financing Authority
(CPCFA). On November 29, 2012, the Water Authority Board adopted a resolution
approving agreements to accomplish tax exempt project financing through the CPCFA.
Based on current electricity cost estimates, the Water Purchase Agreement sets the price of
the water from the Carlsbad Desalination Project at $2,131 to $2,367 per acre foot in 2016.
The Water Authority’s water purchase costs would be financed through Water Authority rates
and charges. Poseidon is financing the capital cost of the Project with a combination of
private equity and tax-exempt Private Activity Bonds.
Written Contracts or Other Proof
The supply and costs associated with the Carlsbad Desalination Project are based primarily on
the following documents:
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
36
Development Agreement between City of Carlsbad and Poseidon (October 2009). A
Development Agreement between Carlsbad and Poseidon was executed on October 5, 2009
Agreement of Term Sheet between the Water Authority and Poseidon Resources (July 2010).
The Water Authority approved the Term Sheet at its July 2010 Board Meeting. The Term
Sheet outlines the terms and conditions of a future Water Purchase Agreement with Poseidon
and allocates the resources to prepare the draft Water Purchase Agreement.
Federal, State, and Local Permits/Approvals
Carlsbad Desalination Project Final EIR
The City of Carlsbad, acting as lead agency for Carlsbad Seawater Desalination Plant and
appurtenant facilities proposed by Poseidon (the “Project”) prepared an Environmental Impact
Report for the Project in compliance with the California Environmental Quality Act
(“CEQA”), which the City of Carlsbad certified on June 13, 2006.
http://www.sdcwa.org/rwfmp-peir
Regional Water Facilities Master Plan EIR
On March 27, 2014, the Water Authority Board of Directors adopted Resolution No. 2014
certifying the Final Supplemental Program Environmental Impact Report (State
Clearinghouse No. 2003021052) for the Water Authority’s 2013 Regional Water Facilities
Optimization and Master Plan Update and Climate Action Plan (the “Master Plan EIR”),
which evaluated, among other things, potential growth inducing impacts associated with new
water supplies to the region including, but not limited to, up to 200 million gallons per day
(“MGD”) of new supplies from seawater desalination. This certification included a 50 MGD
plant located in the City of Carlsbad.
The environmental documents and permits are found at the following links:
https://www.sdcwa.org/master-plan-documents
Sub regional Natural Community Conservation Plan/Habitat Conservation Plan (NCCP/HCP)
On December 8, 2010, the Board adopted Resolution No. 2010-18 certifying a Final
environmental Impact Report/Environmental Impact Statement for the San Diego County
Water Authority Subregional Natural Community Conservation Plan/Habitat Conservation
Plan (State Clearinghouse No. 2003121012) (the “Habitat Conservation Plan EIR/EIS”),
which Plan was implemented on December 28, 201.
The environmental documents and permits are found at the following links:
http://www.sdcwa.org/nccp-hcp
Twin Oaks Valley Water Treatment Plant EIR
On September 8, 2005, the Board adopted Resolution No. 2005-31 certifying a Final
Environmental Impact Report for the Twin Oaks Valley Water Treatment Plant Project (State
Clearinghouse No. 20040071034) (the “Twin Oaks EIR”), which project was constructed as a
100 MGD submerged membrane water treatment facility, including treated water holding
tanks and distribution pipelines and other facilities, consistent with the conditions and
mitigation measures included in the Twin Oaks EIR.
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
37
http://www.sdcwa.org/twin-oaks-valley-treatment-plant-final-eir
Drinking Water Permit (October 2006). The California Department of Health Services
approved the Conditional Drinking Water Permit on October 19, 2006.
6.2.2 Water Authority Capital Improvement Program and Financial
Information
The Water Authority’s Capital Improvement Program (CIP) can trace its beginnings to a
report approved by the Board in 1989 entitled, The Water Distribution Plan, and a Capital
Improvement Program through the Year 2010. The Water Distribution Plan included ten
projects designed to increase the capacity of the aqueduct system, increase the yield from
existing water treatment plants, obtain additional supplies from MWD, and increase the
reliability and flexibility of the aqueduct system. Since that time the Water Authority has
made numerous additions to the list of projects included in its CIP as the region’s
infrastructure needs and water supply outlook have changed.
The current list of projects included in the CIP is based on the results of planning studies,
including the 2015 UWMP and the 2013 Regional Water Facilities Optimization Master Plan
Update. These CIP projects, which are most recently described in the Wate r Authority’s
Adopted Multi-Year Budget Fiscal Years 2020 and 2021, include projects valued at $162
million. These CIP projects are designed to meet projected water supply and delivery needs
of the member agencies. The projects include a mix of new facilities that will add capacity to
existing conveyance, storage, and treatment facilities, as well as repair and replace aging
infrastructure:
Asset Management – The primary components of the asset management projects
include relining and replacing existing pipelines and updating and replacing metering
facilities.
New Facilities – These projects will expand the capacity of the aqueduct system and
evaluate new supply opportunities.
Emergency Storage Project – Projects remaining to be completed under the ongoing
ESP include the San Vicente Dam Raise, the Lake Hodges projects, and a new pump
station to extend ESP supplies to the northern reaches of the Water Authority service
area.
Other Projects – This category includes out-of-region groundwater storage, increased
local water treatment plant capacity, and projects that mitigate environmental impacts
of the CIP.
The Water Authority Board of Directors is provided a semi-annual and annual report on the
status of development of the CIP projects. As described in the Water Authority’s biennial
budget, a combination of long and short term debt and cash (pay-as-you-go) will provide
funding for capital improvements. Additional information is included in the Water
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
38
Authority’s biennial budget, which also contains selected financial information and
summarizes the Water Authority’s investment policy.
6.3 Otay Water District
The Otay Water District WFMP Update and the 2015 UWMP contain comparisons of
projected supply and demands through the year 2040. Projected potable water resources to
meet planned demands as documented were planned to be supplied entirely with imported
water received from the Water Authority. Recycled water resources to meet projected
demands are planned to be supplied from local wastewater treatment plants. The Otay WD
currently has no local supply of raw water, potable water, or groundwater resources.
The development and/or acquisition of potential groundwater, recycled water market
expansion, and seawater desalination supplies by the Otay WD have evolved and are planned
to occur in response to the regional water supply issues. These water supply projects are in
addition to those identified as sustainable supplies in the current Water Authority and MWD
UWMP, IRP, Master Plans, and other planning documents. These new additional water
supply projects are not currently developed and are in various stages of the planning process.
These local and regional water supply projects will allow for less reliance upon imported
water and are considered a new water supply resource for the Otay WD.
The supply forecasts contained within this WSA Report do consider development and/or
acquisition of potential groundwater, recycled water market expansion, and seawater
desalination supplies by the Otay WD.
6.3.1 Availability of Sufficient Supplies and Plans for Acquiring Additional
Supplies
The availability of sufficient potable water supplies and plans for acquiring additional potable
water supplies to serve existing and future demands of the Otay WD is founded upon the
preceding discussions regarding MWD’s and the Water Authority’s water supply resources
and water supplies to be acquired by the Otay WD. Historic imported water deliveries from
the Water Authority to Otay WD and recycled water deliveries from the Otay WD Ralph W.
Chapman Water Reclamation Facility (RWCWRF) are shown in Table 5. Since the year 2000
through mid-May 2007, recycled water demand has exceeded the recycled water supply
capability typically in the summer months. The RWCWRF is limited to a maximum
production of about 1,300 acre-feet per year. The recycled water supply shortfall had been
met by supplementing with potable water into the recycled water storage system as needed by
adding potable water supplied by the Water Authority. On May 18, 2007 an additional source
of recycled water supply from the City of San Diego’s South Bay Water Reclamation Plant
(SBWRP) became available. The supply of recycled water from the SBWRP is a result of
completing construction and the operation of the transmission, storage, and pump station
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
39
systems necessary to link the SBWRP recycled water supply source to the existing Otay WD
recycled water system.
Table 5
Otay Water District
Historic Imported and Local Water Supplies
Calendar
Year
Imported Water
(acre-feet)
Recycled Water
(acre-feet)
Total
(acre-feet)
1980 12,558 0 12,558
1985 14,529 0 14,529
1990 23,200 0 23,200
1995 20,922 614 21,536
2000 29,901 948 30,849
2005 37,678 1,227 38,905
2010 29,270 4,090 33,270
2015 26,494 3,777 30,271
2016 27,289 3,888 31,177
2017 28,045 4,007 32,052
2018 29,286 3,967 33,253
2019 26,803 3,340 30,143
Source: Otay Water District operational records.
6.3.1.1 Imported and Regional Supplies
The availability of sufficient imported and regional potable water supplies to serve existing
and planned uses within Otay WD is demonstrated in the above discussion on MWD and the
Water Authority’s water supply reliability. The County Water Authority Act, Section 5
subdivision 11, states that the Water Authority “as far as practicable, shall provide each of its
member agencies with adequate supplies of water to meet their expanding and increasing
needs.” The Water Authority provides between 75 to 95 percent of the total supplies used by
its 24 member agencies, depending on local weather and supply conditions.
Potable Water System Facilities
The Otay WD continues to pursue diversification of its water supply resources to increase
reliability and flexibility. The Otay WD also continues to plan, design, and construct potable
water system facilities to obtain these supplies and to distribute potable water to meet
customer demands. The Otay WD has successfully negotiated two water supply
diversification agreements that enhance reliability and flexibility, which are briefly described
as follows.
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
40
The Otay WD entered into an agreement with the City of San Diego, known as the Otay
Water Treatment Plant (WTP) Agreement. The Otay WTP Agreement provides for raw
water purchase from the Water Authority and treatment by the City of San Diego at their
Otay WTP for delivery to Otay WD. The supply system link to implement the Otay
WTP Agreement to access the regions raw water supply system and the local water
treatment plant became fully operational in August 2005. This supply link consists of the
typical storage, transmission, pumping, flow measurement, and appurtenances to receive
and transport the treated water to the Otay WD system. The City of San Diego
obligation to supply 10 mgd of treated water under the Otay WTP Agreement is
contingent upon there being available 10 mgd of surplus treatment capacity in the Otay
WTP until such time as Otay WD pays the City of San Diego to expand the Otay WTP to
meet the Otay WD future needs. In the event that the City of San Diego’s surplus is
projected to be less than 10 mgd the City of San Diego will consider and not
unreasonably refuse the expansion of the Otay WTP to meet the Otay WD future needs.
The Otay WTP existing rated capacity is 40 mgd with an actual effective capacity of
approximately 34 mgd. The City of San Diego’s typical demand for treated water from
the Otay WTP is approximately 20 mgd. It is at the City of San Diego’s discretion to
utilize either imported raw water delivered by the Water Authority Pipeline No. 3 or local
water stored in Lower Otay Reservoir for treatment to supply the Otay WD demand.
The Otay WD entered into an agreement with the Water Authority, known as the East
County Regional Treated Water Improvement Program (ECRTWIP Agreement). The
ECRTWIP Agreement provides for transmission of raw water to the Helix WD R. M.
Levy WTP for treatment and delivery to Otay WD. The supply system link to implement
the ECRTWIP Agreement is complete allowing access to the regions raw water supply
system and the local water treatment plant. This supply link consists of the typical
transmission, pumping, storage, flow control, and appurtenances to receive and transport
the potable water from the R. M. Levy WTP to Otay WD.
Cost and Financing
The capital improvement costs associated with water supply and delivery are financed
through the Otay WD water meter capacity fee and user rate structures. The Otay WD
potable water sales revenue are used to pay for the wholesale cost of the treated water supply
and the operating and maintenance expenses of the potable water system facilities.
Written Agreements, Contracts, or Other Proof
The supply and cost associated with deliveries of treated water from the Otay WTP and the R.M.
Levy WTP is based on the following documents.
Agreement for the Purchase of Treated Water from the Otay Water Treatment Plant between the
City of San Diego and the Otay Water District. The Otay WD entered into an agreement dated
January 11, 1999 with the City of San Diego that provides for 10 mgd of surplus treated water to
the Otay WD from the existing Otay WTP capacity. The agreement allows for the purchase of
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
41
treated water on an as available basis from the Otay WTP. The Otay WD pays the Water
Authority at the prevailing raw water rate for raw water and pays the City of San Diego at a rate
equal to the actual cost of treatment to potable water standards.
Agreement between the San Diego County Water Authority and Otay Water District Regarding
Implementation of the East County Regional Treated Water Improvement Program. The
ECRTWIP Agreement requires the purchase of potable water from the Helix WD R.M. Levy
WTP at the prevailing Water Authority treated water rate. The ECRTWIP Agreement is dated
April 27, 2006.
Agreement between the San Diego County Water Authority and Otay Water District for Design,
Construction, Operation, and Maintenance of the Otay 14 Flow Control Facility Modification.
The Otay WD entered into the Otay 14 Flow Control Facility Modification Agreement dated
January 24, 2007 with the Water Authority to increase the physical capacity of the Otay 14 Flow
Control Facility. The Water Authority and Otay WD shared the capital cost to expand its
capacity from 8 mgd to 16 mgd.
Federal, State, and Local Permits/Approvals
The Otay WD acquired all the permits for the construction of the pipeline and pump station
associated with the Otay WTP supply source and for the 640-1 and 640-2 water storage
reservoirs project associated with the ECRTWIP Agreement through the typical planning,
environmental approval, design, and construction processes.
The transmission main project constructed about 26,000 feet of a 36-inch diameter steel
pipeline from the Otay 14 Flow Control Facility to the 640-1 and 640-2 Reservoirs project.
The Otay 14 Flow Control Facility modification increased the capacity of the existing systems
from 8 mgd to 16 mgd. CEQA documentation is complete for both projects. Construction of
both of these projects was completed October 2010.
The City of San Diego and the Helix Water District are required to meet all applicable federal,
state, and local health and water quality requirements for the potable water produced at the
Otay WTP and the R.M. Levy WTP respectively.
6.3.1.2 Recycled Water Supplies
Wastewater collection, treatment, and disposal services provided by the Otay WD is limited to
a relatively small area within what is known as the Jamacha Basin, located within the Middle
Sweetwater River Basin watershed upstream of the Sweetwater Reservoir and downstream of
Loveland Reservoir. Water recycling is defined as the treatment and disinfection of
municipal wastewater to provide a water supply suitable for non-potable reuse. The Otay WD
owns and operates the Ralph W. Chapman Water Reclamation Facility, which produces
recycled water treated to a tertiary level for landscape irrigation purposes. The recycled water
market area of the Otay WD is located primarily within the eastern area of the City of Chula
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
42
Vista. The Otay WD distributes recycled water to a substantial market area that includes but
is not limited to the Elite Athlete Training Center, the Eastlake Golf Course, Otay Ranch, and
other development projects.
The Otay WD projects that annual average demands for recycled water will increase to 6,500
acre-feet per year by 2050. About 1,300 acre-feet per year of supply is generated by the
RWCWRF, with the remainder planned to be supplied to Otay WD by the City of San
Diego’s SBWRP.
Recycled Water System Facilities
The Otay WD has constructed recycled water storage, pumping, transmission, and distribution
facilities and will continue to construct these facilities to meet projected recycled water
market demands. The Supply Link project consisting of a transmission main, storage
reservoir, and a pump station to receive and transport the recycled water from the City of San
Diego’s SBWRP was completed in 2007 and recycled water deliveries began on May 18,
2007.
Cost and Financing
The capital improvement costs associated with the recycled water supply and distribution
systems are financed through the Otay WD water meter capacity fee and user rate structures.
The Otay WD recycled water sales revenue, along with MWD and the Water Authority’s
recycled water sales incentive programs are used to help offset the costs for the wholesale
purchase and production of the recycled water supply, the operating and maintenance
expenses, and the capital costs of the recycled water system facilities.
Written Agreements, Contracts, or Other Proof
The supply and cost associated with deliveries of recycled water from the SBWRP is based on
the following document.
Agreement between the Otay Water District and the City of San Diego for Purchase of
Reclaimed Water from the South Bay Water Reclamation Plant. The agreement provides for the
purchase of at least 6,721 acre-feet per year of recycled water from the SBWRP at an initial price
of $350 per acre-foot. The Otay Water District Board of Directors approved the final agreement
on June 4, 2003 and the San Diego City Council approved the final agreement on October 20,
2003. Effective January 1, 2016, the City of San Diego raised the cost of recycled water 116% to
$754 per acre-foot.
Federal, State, and Local Permits/Approvals
The Otay WD has in place an agreement with MWD for their recycled water sales incentive
program for supplies from the RWCWRF and the SBWRP. Also, the Otay WD has in place
an agreement with the Water Authority for their recycled water sales incentive program for
supplies from the RWCWRF and the SBWRP. The Water Authority sales incentive
Otay Water District
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Sunbow II, Phase 3 Project
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agreement was approved by Water Authority on July 26, 2007 and by Otay WD on August 1,
2007. All permits for the construction of the recycled water facilities to receive, store, and
pump the SBWRP supply have been acquired through the typical planning, environmental
approval, design, and construction processes.
The California Regional Water Quality Control Board San Diego Region (RWQCB) “Master
Reclamation Permit for Otay Water District Ralph W. Chapman Reclamation Facility” was
adopted on May 9, 2007 (Order No. R9-2007-0038). This order establishes master
reclamation requirements for the production, distribution, and use of recycled water in the
Otay WD service area. The order includes the use of tertiary treated water produced and
received from the City of San Diego‘s SBWRP. Recycled water received from and produced
by the SBWRP is regulated by Regional Board Order No. 2000-203 and addenda. The City
of San Diego is required to meet all applicable federal, state, and local health and water
quality requirements for the recycled water produced at the SBWRP and delivered to Otay
WD in conformance with Order No. 2000-203.
6.3.1.3 Potential Groundwater Supplies
The Otay Water District WFMP Update, 2015 UWMP, and the 2015 Integrated Water
Resources Plan Update all contain a description of the development of potential groundwater
supplies. Over the past several years, Otay WD has studied numerous potential groundwater
supply options that have shown, through groundwater monitoring well activities, poor quality
water and/or insufficient yield from the basins at a cost-effective level. The Otay WD has
developed capital improvement program projects to continue the quest to develop potential
groundwater resources. Local Otay WD groundwater supply development is currently
considered as a viable water supply resource to meet projected demands.
The development and/or acquisition of potential groundwater supply projects by the Otay WD
have been on hold in response to the regional water supply issues related to water source
supply conditions. Local ground water supply projects will allow for less reliance upon
imported water, achieve a level of independence of the regional wholesale water agencies, and
diversify the Otay WD water supply portfolio consistent with the Otay Water District 2015
IRP Update.
In recognition of the need to develop sufficient alternative water supplies, the Otay WD has
taken the appropriate next steps towards development of production groundwater well
projects.
The Otay WD is actively pursuing the Middle Sweetwater River Basin Groundwater Well
project.
Middle Sweetwater River Basin Groundwater Well
The Middle Sweetwater River Basin Groundwater Well is an additional water supply project
that was thoroughly studied and documented in the 1990s. The Middle Sweetwater River
Otay Water District
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44
Basin is located within the Sweetwater River watershed and that reach of the river extends
from Sweetwater Reservoir to the upstream Loveland Reservoir. The next step in
development of the Middle Sweetwater River Basin Groundwater Well is the implementation
of a pilot well project. The ultimate objective of the Otay WD is to develop a groundwater
well production system within the Middle Sweetwater River Basin capable of producing a
sustainable yield of potable water as a local supply.
The purpose of the Middle Sweetwater River Basin Groundwater Well Pilot project is to
identify the feasibility of developing a groundwater resource production system and then
determine and assess any limitations or constraints that may arise. The Middle Sweetwater
River Basin Groundwater Well Pilot Project will accomplish six primary goals:
Update project setting
Update applicable project alternatives analysis
Prepare groundwater well pilot project implementation plan
Construct and test pilot monitoring and extraction wells
Provide recommendations regarding costs and feasibility to develop a groundwater
well production system within the Middle Sweetwater River Basin capable of
producing a sustainable yield of potable water
Prepare groundwater well production project implementation plan and scope of work
The groundwater conjunctive use concept is described as the extraction of the quantity of
water from the groundwater basin that was placed there by customers of the Otay Water
District, Helix Water District, and Padre Dam Municipal Water District by means of their use
of imported treated water that contributed to the overall volume of groundwater within the
basin. An estimated quantity was developed to be approximately 12.5 percent of the total
consumption of the Otay WD customers within that basin, as measured by water meters. In
the 1994-1995 period, the quantity of water that was returned to the groundwater basin by
Otay WD customers was estimated to be 810 acre-feet per year. Currently, that 12.5 percent
quantity could be on the order of 1,000 acre-feet per year. A future scope of work will need
to address this concept while considering further development of the groundwater basin as an
additional supply resource. If it is deemed that a Middle Sweetwater River Basin
Groundwater Well Production Project is viable then the consultant will develop and provide a
groundwater well production project implementation plan, cost estimate, and related scope of
work.
Further development of the groundwater basin to enhance the total groundwater production
could be accomplished by the Otay WD by means of additional extraction of water from the
basin that is placed there by means of either injection and/or spreading basins using imported
untreated water as the resource supply. The existing La Mesa Sweetwater Extension Pipeline,
owned by the Water Authority, once converted to an untreated water delivery system, could
be the conveyance system to transport untreated water for groundwater recharge in support of
this conjunctive use concept. These two distinct water resource supply conjunctive use
concepts will be addressed so they may coexist and to allow for their development as separate
phases.
Otay Water District
Water Supply Assessment and Verification Report
Sunbow II, Phase 3 Project
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The scope of work to complete Middle Sweetwater River Basin Groundwater Well Pilot
Project consists of many major tasks and is to address the groundwater supply concepts
outlined above. It is anticipated that the cost for the entire scope of work, will be on the order
of $2,000,000, which includes a contingency and may take up to one and a half years to
complete.
The primary desired outcome of the Middle Sweetwater River Basin Groundwater Well Pilot
Project is for the engineering consultant to determine and make recommendations if it is
financially prudent and physically feasible to develop a Phase I groundwater well production
system within the Middle Sweetwater River Basin capable of producing a sustainable yield of
up to 1,500 ac-ft/yr of potable water for the Otay WD. If it is deemed that a Middle
Sweetwater River Basin Groundwater Well Production Project is viable then the consultant
will develop and provide a groundwater well production project implementation plan and
related scope of work.
Rancho del Rey Well Groundwater Well Project
In 1991, the McMillin Development Company drilled the Rancho del Rey Groundwater Well
to augment grading water supplies for their Rancho del Rey development projects. Although
the well was considered a “good producer,” little was known regarding its water quality and
sustainable yield because the water was used solely for earthwork (i.e. dust control and soil
compaction). The well was drilled to 865 feet, with a finished depth of 830 feet and produced
approximately 400 AFY of low quality water for four years until its use was discontinued in
April 1995 when the well was no longer needed. McMillin notified the Otay WD of its intent
to sell off the groundwater well asset.
In 1997, the Otay WD purchased an existing 7-inch well and the surrounding property on
Rancho del Rey Parkway from the McMillin Company with the intent to develop it as a
source of potable water. Treatment was required to remove salts and boron, among other
constituents, using reverse osmosis membranes and ion exchange.
In 2000, having received proposals for the design and construction of a reverse osmosis
treatment facility that far exceeded the allocated budget, the Board of Directors instructed
staff to suspend the project until such time as it became economically viable.
In January 2010, citing the rising cost of imported water and the Otay WD's interest in
securing its own water source for long-term supply reliability, the Board authorized Phase 1
for drilling and development of the Rancho del Rey Well.
On March 3, 2010, the Board adopted the Mitigated Negative Declaration for this project and
a Notice of Determination was filed with the County of San Diego on March 5, 2010. In
September 2010, a new 12-inch production well was drilled to a depth of 900 feet through the
groundwater formation and into fractured bedrock. Testing showed the long-term yield of the
new well to be 450 gpm, higher than previous studies had estimated. Separation Processes,
Otay Water District
Water Supply Assessment and Verification Report
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Inc. (SPI), a highly qualified membrane treatment firm, was hired to conduct a detailed
economic feasibility study to confirm that the annualized unit cost of the new water source
was economically competitive with other sources. The economic study estimated the unit
cost of water to be $1, 500 to $2,000 per AF for an alternative that utilizes a seawater
membrane for treating both salts and boron. When compared with the current imported
treated water rate from the Water Authority, and with the knowledge that this rate will
continually increase as MWD and the Water Authority raise their rates, the Rancho del Rey
Well project appears to be economically viable.
The Otay WD is continuing to pursue the Rancho del Rey groundwater well opportunity with
due consideration of the recommendations of the existing reports and plans to develop a
groundwater well production facility to extract approximately 500 AFY. For water planning
purposes, production of groundwater from the Rancho del Rey well is considered “additional
planned” for local supplies.
Otay Mesa Lot 7 Groundwater Well
In early 2001 the Otay WD was approached by a landowner representative about possible
interest in purchasing an existing well or alternatively, acquiring groundwater supplied from
the well located on Otay Mesa. The landowner, National Enterprises, Inc., reportedly stated
that the well could produce 3,200 acre-feet per year with little or no treatment required prior
to introducing the water into the Otay WD potable water system or alternatively, the recycled
water system. In March 2001 authorization to proceed with testing of the Otay Mesa Lot 7
Groundwater Well was obtained and the Otay WD proceeded with the investigation of this
potential groundwater supply opportunity.
The May 2001 Geoscience Support Services, Inc. completed for the Otay WD the preparation
of a report entitled, “Otay Mesa Lot 7 Well Investigation,” to assess the Otay Mesa Lot 7
Well. The scope of work included a geohydrologic evaluation of the well, analyses of the
water quality samples, management and review of the well video log, and documentation of
well pump testing. The primary findings, as documented in the report, formed the basis of the
following recommendations:
For the existing well to be used as a potable water supply resource, a sanitary seal
must be installed in accordance with the CDPH guidelines.
Drawdown in the well must be limited to avoid the possibility of collapsing the casing.
Recover from drawdown from pumping is slow and extraction would need to be
terminated for up to 2 days to allow for groundwater level recovery.
The well water would need to be treated and/or blended with potable water prior to
introduction into the potable water distribution system.
The existing Otay Mesa Lot 7 Well, based upon the above findings, was determined not to be
a reliable municipal supply of potable water and that better water quality and quantity perhaps
could be discovered deeper or at an alternative location within the San Diego Formation.
Otay Water District
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The Otay WD may still continue to pursue the Otay Mesa groundwater well opportunity with
due consideration of the recommendations of the existing report. Based on the
recommendations of the investigation report, a groundwater well production facility at Otay
Mesa Lot 7 could realistically extract approximately 300 acre-feet per year.
6.3.1.4 Otay Water District Rosarito Ocean Desalination Project
The Otay WD is considering the feasibility of purchasing desalinated water from a seawater
reverse osmosis plant that may be located in Rosarito, Mexico. The treatment facility would
be designed, constructed, and operated in Mexico by a third party. The Otay WD’s draft
Desalination Feasibility Study, prepared in 2008, discusses the likely issues to be considered
in terms of water treatment and monitoring, potential conveyance options within the United
States from the international border to potential delivery points, and environmental,
institutional, and permitting considerations for the Otay WD to import the Desalination
project product water as a new local water supply resource.
While the treatment facility for a Desalination project would not be designed or operated by
the Otay WD, it will be important that the Otay WD maintain involvement with the planning,
design, and construction of any future facility to ensure that the implemented processes
provide a product water of acceptable quality for distribution and use within the Otay WD’s
system as well as in other regional agencies’ systems that may use the product water, i.e. City
of San Diego, the Water Authority, etc. A seawater reverse osmosis treatment plant removes
constituents of concern from the seawater, producing a water quality that far exceeds
established United States and California drinking water regulations for most parameters,
however, a two-pass treatment system may be required to meet acceptable concentrations of
boron and chlorides, similar to the levels seen within the existing Otay WD supply
sources. The Desalination Feasibility Study addresses product water quality that is considered
acceptable for public health and distribution.
The Otay WD, or any other potential participating agencies, would be required to get approval
from the DDW in order to use the desalinated seawater as a water source. Several alternative
approaches are identified for getting this approval. These alternatives vary in their cost and
their likelihood of meeting DDW approval.
The Rosarito Desalination Facility Conveyance and Disinfection System Project report
addresses two supply targets for the desalinated water (i.e. local and regional). The local
alternative assumes that only Otay WD would participate and receive desalinated water, while
the regional alternative assumes that other regional and/or local agencies would also
participate in the Rosarito project.
6.3.2 Otay Water District Capital Improvement Program
The Otay WD plans, designs, constructs, and operates water system facilities to acquire
sufficient supplies and to meet projected ultimate demands placed upon the potable and recycled
water systems. In addition, the Otay WD forecasts needs and plans for water supply
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requirements to meet projected demands at ultimate build out. The necessary water facilities and
water supply projects are implemented and constructed when development activities proceed and
require service to achieve timely and adequate cost-effective water service.
New water facilities that are required to accommodate the forecasted growth within the entire
Otay WD service area are defined and described within the Otay Water District WFMP Update.
These facilities are incorporated into the annual Otay WD Six Year Capital Improvement
Program (CIP) for implementation when required to support development activities. As major
development plans are formulated and proceed through the land use jurisdictional agency
approval processes, Otay WD prepares water system requirements specifically for the proposed
development project consistent with the Otay WD WFMP Update. These requirements
document, define, and describe all the potable water and recycled water system facilities to be
constructed to provide an acceptable and adequate level of service to the proposed land uses, as
well as the financial responsibility of the facilities required for service. The Otay WD funds the
facilities identified as CIP projects. Established water meter capacity fees and user rates are
collected to fund the CIP project facilities. The developer funds all other required water system
facilities to provide water service to their project.
Section 7 – Conclusion: Availability of Sufficient Supplies
The Sunbow II, Phase 3 project is currently located within the jurisdictions of the Otay WD,
Water Authority, and MWD. To obtain permanent imported water supply service, land areas
are required to be within the jurisdictions of the Otay WD, Water Authority, and MWD to
utilize imported water supply.
The Water Authority and MWD have an established process that ensures supplies are being
planned to meet future growth. Any annexations and revisions to established land use plans
are captured in the SANDAG updated forecasts for land use planning, demographics, and
economic projections. SANDAG serves as the regional, intergovernmental planning agency
that develops and provides forecast information. The Water Authority and MWD update their
demand forecasts and supply needs based on the most recent SANDAG forecast
approximately every five years to coincide with preparation of their urban water management
plans. Prior to the next forecast update, local jurisdictions with land use authority may require
water supply assessment and/or verification reports for proposed land developments that are
not within the Otay WD, Water Authority, or MWD jurisdictions (i.e. pending or proposed
annexations) or that have revised land use plans with either lower or higher development
intensities than reflected in the existing growth forecasts. Proposed land areas with pending
or proposed annexations, or revised land use plans, typically result in creating higher demand
and supply requirements than previously anticipated. The Otay WD, Water Authority, and
MWD next demand forecast and supply requirements and associated planning documents
would then capture any increase or decrease in demands and required supplies as a result of
annexations or revised land use planning decisions.
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MWD’s IRP identifies a mix of resources (imported and local) that, when implemented, will
provide 100 percent reliability for full-service demands through the attainment of regional
targets set for conservation, local supplies, State Water Project supplies, Colorado River
supplies, groundwater banking, and water transfers. The 2015 IRP Update describes an
adaptive management strategy to protect the region from future supply shortages. This
adaptive management strategy has five components: achieve additional conservation savings,
develop additional local water supplies, maintain Colorado River Aqueduct supplies, stabilize
State Water Project supplies, and maximize the effectiveness of storage and transfer. MWD’s
2015 IRP has a plan for identifying and implementing additional resources that expand the
ability for MWD to meet future changes and challenges as necessary to ensure future
reliability of supplies. The proper management of these resources help to ensure that the
southern California region, including San Diego County, will have adequate water supplies to
meet long-term future demands.
MWD adopted its 2015 UWMP, in accordance with state law, on May 9, 2016. The resource
targets included in the preceding 2015 IRP Update serve as the foundation for the planning
assumptions used in the 2015 UWMP. MWD’s 2015 UWMP contains a water supply
reliability assessment that includes a detailed evaluation of the supplies necessary to meet
demands over a 20-year period in average, single dry year, and multiple dry year periods. As
part of this process, MWD also uses the current SANDAG regional growth forecast in
calculating regional water demands for the Water Authority’s service area.
As stated in MWD’s 2015 UWMP, the plan may be used as a source document for meeting
the requirements of SB 610 and SB 221 until the next scheduled update is completed in 5
years (2020). The 2015 UWMP includes a “Justifications for Supply Projections” in
Appendix A.3, that provides detailed documentation of the planning, legal, financial, and
regulatory basis for including each source of supply in the plan.
In the Findings Section of the Executive Summary (Page ES-5) of their 2015 UWMP, MWD
states that MWD has supply capacities that would be sufficient to meet expected demands
from 2020 through 2040 under the single dry-year and multiple dry-year conditions. MWD
has plans for supply implementation and continued development of a diversified resource mix
including programs in the Colorado River Aqueduct, State Water Project, Central Valley
Transfers, local resource projects, and in-region storage that enables the region to meet its
water supply needs. MWD’s 2015 UWMP identifies potential reserve supplies in the supply
capability analysis (Tables 2-4, 2-5 and 2-6), which could be available to meet the
unanticipated demands.
The County Water Authority Act, Section 5 subdivision 11, states that the Water Authority
“as far as practicable, shall provide each of its member agencies with adequate supplies of
water to m eet their expanding and increasing needs.”
As part of preparation of a written water supply assessment report, an agency’s shortage
contingency analysis should be considered in determining sufficiency of supply. Section 11
of the Water Authority’s 20 15 Updated UWMP contains a detailed shortage contingency
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analysis that addresses a regional catastrophic shortage situation and drought management.
The analysis demonstrates that the Water Authority and its member agencies, through the
Integrated Contingency Plan, Emergency Storage Project, Carlsbad Desalination Project, and
Water Shortage Contingency Plan are taking actions to prepare for and appropriately handle
an interruption of water supplies. The 2017 Water Shortage Contingency Plan provides the
Water Authority and its member agencies with a series of potential actions to take when faced
with a shortage of imported water supplies from MWD due to prolonged drought or other
supply shortfall conditions. The actions will help the region avoid or minimize the impacts of
shortages and ensure an equitable allocation of supplies.
The WSA&V Report identifies and describes the processes by which water demand
projections for the proposed Sunbow II, Phase 3 project will be fully included in the water
demand and supply forecasts of the Urban Water Management Plans and other water
resources planning documents of the Water Authority and MWD. Water supplies necessary
to serve the demands of the proposed Sunbow II, Phase 3 project, along with existing and
other projected future users, as well as the actions necessary and status to develop these
supplies, have been identified in the Sunbow II, Phase 3 project WSA&V Report and will be
included in the future water supply planning documents of the Water Authority and MWD.
This WSA&V Report includes, among other information, an identification of existing water
supply entitlements, water rights, water service contracts, water supply projects, or
agreements relevant to the identified water supply needs for the proposed Sunbow II, Phase 3
project. This WSA Report assesses, demonstrates, and documents that sufficient water
supplies are planned for and are intended to be available over a 20-year planning horizon,
under normal conditions and in single and multiple dry years to meet the projected demand of
the proposed Sunbow II, Phase 3 project and the existing and other planned development
projects to be served by the Otay WD.
Table 6 presents the forecasted balance of water demands and required supplies for the Otay
WD service area under average or normal year conditions. The total actual demand for FY
2015 was 30,271 acre-feet. The demand for FY 2015 is 2,999 acre-feet lower than the
demand in FY 2010 of 33,270 acre-feet. The drop in demand is a result of the unit price of
water, the conservation efforts of users as a result of the prolonged drought, and the economy.
Table 6 presents the forecasted balance of water demands and supplies for the Otay WD
service area under single dry year conditions. Table 7 presents the forecasted balance of
water demands and supplies for the Otay WD service area under multiple dry year conditions
for the three-year period ending in 2019. The multiple dry year conditions for periods ending
in 2025, 2030, and 2035 are provided in the Otay Water District 2015 UWMP. The projected
potable demand and supply requirements shown the Tables 6 and 7 are from the Otay WD
2015 UWMP. Hot, dry weather may generate urban water demands that are about 6.4 percent
greater than normal. This percentage was utilized to generate the dry year demands shown in
Table 7. The recycled water supplies are assumed to experience no reduction in a dry year.
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Table 6
Projected Balance of Water Demands and Supplies Normal Year Conditions (acre feet)
Description FY 2025 FY 2030 FY 2035 FY 2040
Demands
Otay WD Demands 54,771 57,965 59,279 65,913
Active Conservation Savings (1,844) (1,585) (1,538) (1,587)
Accelerated Forecast Growth (AFG) –
Planning Area 12 46 46 46 46
AFG – Otay Sunroad EOM SPA 836 836 836 836
AFG - University Innovation District 11.7 11.7 11.7 11.7
AFG – Sunbow 2, Phase III 84.7 84.7 84.7 84.7
Passive Conservation Savings (4,497) (5,489) (6,040) (6,744)
Total Demand 49,408.4 51,869.4 52,679.4 58,560.4
Supplies
Water Authority Supply 43,508.4 45,869.4 46,479.4 52,060.4
Recycled Water Supply 5,900 6,000 6,200 6,500
Total Supply 49,408.4 51,869.4 52,679.4 58,560.4
Supply Surplus/(Deficit) 0 0 0 0
Table 7 presents the forecasted balance of water demands and supplies for the Otay WD
service area under single dry year and multiple dry year conditions from the Otay Water
District 2015 UWMP.
Table 7
Projected Balance of Water Demands and Supplies
Single Dry and Multiple Dry Year Conditions (acre feet)
Normal
Year
Single Dry
Year
Multiple Dry Years
FY 2011 First Dry
Year
First Dry
Year
Second
Dry Year
Third Dry
Year
Demands
Otay WD Demands 37,176 38,749 38,844 40,378 42,430
Total Demand 37,176 38,749 38,844 40,378 42,430
Supplies
Water Authority Supply 33,268 33,877 33,972 35,240 37,026
Recycled Water Supply 3,908 4,872 4,872 5,138 5,404
Total Supply 37,176 34,639 38,844 40,378 42,430
Supply Surplus/(Deficit) 0 0 0 0 0
District Demand totals with SBX7 -7 conservation target achievement plus single dry year increase as shown. The Water Authority
could implement its DMP. In this instance, the Water Authority may have to allocate supply shortages based on it equitable allocation
methodology in its DMP.
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Dry year demands assumed to generate a 7% increase in demand over normal conditions for a
single dry year. For multiple dry years an 8% increase in demand over normal conditions is
projected in the first year, 14% in the second year and 21% increase is projected in the third
year in addition to new demand growth.
In evaluating the availability of sufficient water supply, the Sunbow II, Phase 3 project
development proponents will be required to participate in the development of alternative
water supply project(s). This can be achieved through payment of the New Water Supply Fee
adopted by the Otay WD Board in May 2010. These water supply projects are in addition to
those identified as sustainable supplies in the current Water Authority and MWD UWMP,
IRP, Master Plans, and other planning documents. These new water supply projects are in
response to the regional water supply issues related to climatological, environmental, legal,
and other challenges that impact water source supply conditions, such as the court rulings
regarding the Sacramento-San Joaquin Delta and the current ongoing western states drought
conditions. These new additional water supply projects are not currently developed and are in
various stages of the planning process. The Otay WD water supply development program
includes but is not limited to projects such as the Middle Sweetwater River Basin
Groundwater Well project and the Rancho del Rey Groundwater Well project. The Water
Authority and MWD’s next forecasts and supply planning documents would capture any
increase in water supplies resulting from any new water resources developed by the Otay WD.
The Otay WD acknowledges the ever-present challenge of balancing water supply with
demand and the inherent need to possess a flexible and adaptable water supply
implementation strategy that can be relied upon during normal and dry weather conditions.
The responsible regional water supply agencies have and will continue to adapt their resource
plans and strategies to meet climate, environmental, and legal challenges so that they may
continue to provide water supplies to their service areas. The regional water suppliers along
with Otay WD fully intend to maintain sufficient reliable supplies through the 20-year
planning horizon under normal, single, and multiple dry year conditions to meet projected
demand of the Sunbow II, Phase 3 project, along with existing and other planned development
projects within the Otay WD service area.
This WSA&V Report assesses, demonstrates, and documents that sufficient water supplies are
planned for and are intended to be acquired, as well as the actions necessary and status to
develop these supplies, to meet projected water demands of the Sunbow II, Phase 3 project as
well as existing and other reasonably foreseeable planned development projects within the
Otay WD for a 20-year planning horizon, in normal and in single and multiple dry years.
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Source Documents
Sunbow II, Phase 3 SB 610 and SB 221 Compliance request letter received November 4,
2020.
CH2M and Otay Water District, “Otay Water District 2015 Urban Water Management Plan
Update”, May 2016.
Otay Water District, “2015 Water Facilities Master Plan Update,” dated March 2016.
Carollo and Otay Water District, 2015 Integrated Water Resources Plan Update, June 2015.
San Diego County Water Authority, “Final 2015 Urban Water Management Plan, June, 2016.
MWD Water District of Southern California, “2015 Urban Water Management Plan,” June
2016.
PBS&J, “Draft Otay Water District North District Recycled Water System Development
Project, Phase I Concept Study,” December 2008.
NBS Lowry, “Middle Sweetwater River System Study Water Resources Audit,” June 1991.
Michael R. Welch, “Middle Sweetwater River System Study Alternatives Evaluation,” May
1993.
Michael R. Welch, “Middle Sweetwater River Basin Conjunctive Use Alternatives,”
September 1994.
Geoscience Support Services, Inc., “Otay Mesa Lot 7 Well Investigation,” May 2001.
Boyle Engineering Corporation, “Groundwater Treatment Feasibility Study Ranch del Rey
Well Site,” September 1996.
Agreement for the Purchase of Treated Water from the Otay Water Treatment Plant between
the City of San Diego and the Otay Water District.
Agreement between the San Diego County Water Authority and Otay Water District regarding
Implementation of the East County Regional Treated Water Improvement Program.
Agreement between the San Diego County Water Authority and Otay Water District for
Design, Construction, Operation, and Maintenance of the Otay 14 Flow Control Facility
Modification.
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Agreement between the Otay Water District and the City of San Diego for Purchase of
Reclaimed Water from the South Bay Water Reclamation Plant.
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Appendix A
Sunbow II, Phase 3 Project Vicinity Map
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Appendix B
Sunbow II, Phase 3 Project Development Plan