Services of the San Francisco Public Utilities Commission
OUR MISSION: To provide our customers with high-quality, efficient and reliable water, power and sewer services in a manner that values environmental and community interests and sustains the resources entrusted to our care.
525 Golden Gate Avenue, 13th Floor
San Francisco, CA 94102
T 415.554.3155
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TTY 415.554.3488
January 29, 2024
Ms. Sue Parker Ms. Erika Contreras
Chief Clerk of the Assembly Secretary of Senate
California Legislature California Legislature
State Capitol, Room 3196 State Capitol, Room 3044
Sacramento, CA 95814 Sacramento, CA 95814
Darrin Polhemus
Division of Drinking Water, Director
State Water Resources Control Board
1001 I St., 24th Floor
Sacramento, CA 95814
Dr. Tomás J. Aragón, M.D., Dr. P.H.
Director and State Public Health Officer
California Department of Public Health
P.O. Box 997377, MS 0500
Sacramento, CA 95899-7377
Dear Madams and Sirs:
In accordance with Assembly Bill 1823, a bill codified in Chapter 841 of the California Water Code, Section 73504(a), the San Francisco Public Utilities Commission (SFPUC) is herewith reporting on the progress it has made during 2023 in securing additional water supplies to supplement its Hetch Hetchy Regional Water System supply during dry years.
This past year, the SFPUC has continued the implementation of its water supply projects in the Water System Improvement Program (WSIP). The projects remain close to completion. The dry-year water supply projects included in WSIP were designed to allow the SFPUC to meet at least 80 percent of its customer demand during droughts assuming current system supplies and operation and rationing up to no more than 20 percent in any one year of a drought. However, the SFPUC’s ability to meet its customer demand during dry years may be affected by the State Water Resources Control Board’s amendment to the Water Quality Control Plan for the San Francisco Bay / Sacramento-San Joaquin Delta Estuary (Bay-Delta Plan Amendment), which was adopted in December 2018. The Bay-Delta Plan Amendment calls for the release of 40% of the unimpaired flow in the Tuolumne River from Don Pedro Reservoir. The SFPUC staff analysis of the Bay-Delta Plan Amendment shows that its implementation could cause a significant reduction in available water supply and an associated need to increase rationing to up to 50% during droughts in SFPUC’s service area. SFPUC staff continue to engage in negotiations with other parties and the State to reach a voluntary settlement
agreement. Meanwhile, planning for new, alternative water supplies is ongoing and is described below.
The SFPUC has continued planning that was initiated in 2020 for additional water supply under the Alternative Water Supply (AWS) Program to meet future dry-year water needs in the SFPUC service area. The planning efforts involve evaluating new storage and supply opportunities throughout the SFPUC’s service area to meet anticipated future needs. The projects outlined below are regional projects that could contribute to increasing SFPUC’s water supplies for dry years. Several of the projects described remain in the planning and feasibility study stage, requiring additional analysis and resources.
• Regional Groundwater Storage and Recovery (RGSR) Project – The RGSR Project is a strategic partnership between the SFPUC and three partner agencies: the City of Daly City, the City of San Bruno and the California Water Service Company (serving South San Francisco and Colma). The project sustainably manages groundwater and surface water resources in a way that provides supplies during times of drought. During years of normal or heavy rainfall, the project would provide additional surface water to the partner agencies in San Mateo County, allowing them to reduce the amount of groundwater that they pump from the South Westside Groundwater Basin. Over time, the reduced pumping would allow the aquifer to naturally recharge and result in increased groundwater storage of up to 20 billion gallons of new water supply available during dry years. Phase 1 of this project consisted of construction of thirteen well sites and was completed in 2022. Phase 2 has been separated into two contracts. Phase 2A consists of inspection and service of each well and existing well pumps, addition of variable frequency drives to improve efficiency, and installation of cathodic protection to address potential corrosion. Substantial completion for the Phase 2A contract is anticipated in December 2024. Phase 2B consists of work at SSF Main Well and pipeline installation to connect the well to Cal Water's treatment facility. The design phase was completed in 2023 and the contract went out to bid, with a qualified bid received this month. Notice to proceed is expected in summer of 2024, with an anticipated construction duration of 30 months.
• Daly City Recycled Water Expansion Project - This is a recycled water project that will produce approximately 1 mgd of recycled water on an average annual basis. The primary purpose of the project is to provide recycled water to local cemeteries and other smaller irrigation customers, offsetting existing groundwater pumping from the South Westside Groundwater Basin (Basin); this will free up groundwater, enhancing the reliability of the Basin. The project is a regional partnership between the SFPUC and Daly City, and the irrigation customers are located largely
within California Water Service Company's (Cal Water) service area.
SFPUC customers will benefit from the increased reliability of the South Westside Groundwater Basin for additional drinking water supply during droughts. In this way, this project supports the RGSR Project described above, which is under construction. In 2023, negotiations on the terms of the project began with partner agencies. Cost estimates were also developed. Agreements among the partner agencies for the design phase of the project are currently being developed.
• Alameda County Water District-Union Sanitary District Purified Water Project - This project can provide a new purified water supply utilizing Union Sanitary District’s treated wastewater and further treating it through a multi-barrier advanced treatment process to meet or exceed drinking water standards. Purified water produced by Union Sanitary District will be transmitted to the Quarry Lakes Groundwater Recharge Area to supplement recharge into the Niles Cone Groundwater Basin or for other uses in Alameda County Water District's (ACWD's) service area. With the additional water supply to ACWD, an in-lieu exchange with the SFPUC would result in more water left in the SFPUC's Regional Water System.
Additional water supply could also be directly transmitted to the SFPUC through a new intertie between ACWD and SFPUC. In 2023, the project team completed the feasibility study that includes the technical analyses of two alternatives that consist of purified water concepts involving groundwater recharge through the Quarry Lakes as a first phase and providing water supply to ACWD or the SFPUC directly as a second phase.
There are two variations of this phased concept based on whether or not planned capital improvements at the wastewater treatment facility are assumed.
• PureWater Peninsula Project - This purified water project could provide 6- 12 mgd of water supply through reservoir water augmentation at Crystal Springs Reservoir in San Mateo County, within the SFPUC's Regional Water System. Treated wastewater from Silicon Valley Clean Water and/or the City of San Mateo would go through a water purification process that uses multi-barrier treatment technology to meet state and federal drinking water quality standards. The purified water would then be transmitted 10-20 miles (depending on the alignment) to Crystal Springs Reservoir, blended with regional surface water supplies and treated again at Harry Tracy Treatment Plant. In addition to the SFPUC and the wastewater agencies, Cal Water, the Mid-Peninsula Water District, Redwood City and the Bay Area Water Supply & Conservation Agency (BAWSCA) are also participating directly in the project. In 2023, the SFPUC, partner agencies, and the consultant team completed Phase 3 of the feasibility study and have nearly completed the Basis of Design Report. In parallel, the SFPUC
is exploring a parallel project alternative that would bring 12 mgd of purified water directly, through treated water augmentation, to the RWS. This study will be completed in 2024, prior to the preparation of an Alternative Analysis Report for the project as its planning progresses.
• South Bay Purified Water Project - The SFPUC, the City of San Jose, and the City of Santa Clara launched a project partnership to explore and potentially implement a joint purified water project that would serve the local demands of San Jose and Santa Clara during all types of water years, while also supplementing the water supply provided through the SFPUC’s RWS in dry years. An initial concept that is being explored is a 10-mgd advanced water treatment facility (i.e., purified water facility) that would use source water from the San Jose-Santa Clara Regional Wastewater Facility and operate at 6.5-mgd capacity during wet and normal years. During dry years, the facility would ramp up to the full 10-mgd capacity. The additional
3.5 mgd of purified water produced during dry years would be fed into the RWS to increase dry-year reliability. The Feasibility Study for this project was successfully completed in 2023. The project partners are now determining additional technical studies needed for continued project planning.
• Los Vaqueros Reservoir Expansion Project - The Los Vaqueros Reservoir Expansion Project is a storage project that will expand the existing reservoir located in northeastern Contra Costa County from 160,000 acre-feet to 275,000 acre-feet. The main objectives of the expansion include increasing water supply reliability for municipal, industrial, and agricultural customers as well as ecosystem benefits to south-of-Delta wildlife refuges and Delta fisheries. While the existing reservoir is owned and operated by Contra Costa Water District (CCWD), the expansion will have regional benefits and will be managed by a Joint Powers Authority (JPA), which was established in October 2021 that will be set up prior to construction. Storage in the expanded reservoir can provide a dry-year water supply benefit to the SFPUC's Regional Water System. In 2023, the SFPUC’s focus has been on identifying sources of supply to store in an expanded Los Vaqueros Reservoir (see LVE Supply Alternatives below). Meanwhile, the SFPUC continued to work closely with the project partners to contribute to the development of this project from executive participation at the JPA Board of Directors and in various committees to staff engagement and participation in technical, financial, operational, and legal aspects of the project. Design of the enlarged dam has been completed, and the project team continues to work toward securing necessary permits and agreements ahead of project implementation.
• LVE Supply Alternatives (formerly Bay Area Brackish Water Desalination) - The LVE Supply Alternatives is a project to identify and secure one or more supply sources to store water in the SFPUC’s share of expanded storage in the Los Vaqueros Reservoir. Desalination, groundwater demineralization, transfers, and purified water are among the supplies under consideration. In 2023, several opportunities were identified and are currently being evaluated.
• Calaveras Reservoir Expansion Project - This storage project envisions the expansion of Calaveras Reservoir to store excess Regional Water System supplies or other source water in wet and normal years. No expansion of water rights from the local watershed is anticipated. With the Calaveras Dam Replacement project in place, Calaveras Dam holds a capacity of 96,850 acre-feet, or 31 billion gallons of water. Through an expansion, up to an additional 289,000 acre-feet, or 94 billion gallons of storage could be realized. The expansion of Calaveras Reservoir would provide storage for additional water that can be available in all water year types. The proposed project would include raising the dam, increasing the capacity of the outlet structures and the spillway, and the addition of any transmission and pumping needed to bring water to Calaveras Reservoir. In 2023, SFPUC staff completed a preliminary evaluation of conveyance alternatives and associated costs. Due to the challenges of expanding conveyance in the region, planning for this project is being deferred while other alternative supply and storage projects continue to be evaluated.
In addition to the above projects that are in the planning and feasibility study stage, the SFPUC is engaged in conversations on various other projects, including new interconnections, water transfers and exchanges through the Bay Area Regional Reliability (BARR) Partnership. In 2023, BARR partners completed the Shared Water Access Program Strategy Report, with the assistance of a U.S. Bureau of Reclamation grant. This effort is intended to help streamline regional efforts to deliver water during droughts by identifying barriers and opportunities through pilot studies.
The SFPUC and its Wholesale Customers also continue to advance conservation within our service areas. In addition to demand reduction measures, the SFPUC is simultaneously pursuing studies to evaluate the potential for additional recycled water and purified water in San Francisco and investing in innovation that can result in further demand reduction or supply increases, such as atmospheric water generation technology. Through June 2023, these efforts have been captured under the Alternative Water Supply Planning initiative and quarterly updates provided to the SFPUC Commission, and will continue on an annual basis. In addition, in 2023, the SFPUC also prepared the Draft Alternative Water Supply Plan, a report that takes a
comprehensive view of the need for alternative water supply and storage and identifies actions for the SFPUC, including the planning of projects described in this letter. This draft report can be found online: Alternative Water Supply Plan (sfpuc.org). A final report, incorporating public comments received, will be available soon at the same location.
Implementation of the WSIP dry-year projects and the pursuit of alternative water supplies to meet future needs are necessary to ensure sufficient water during droughts for our Retail and Wholesale Customers. These efforts will continue to carry the upmost importance to the SFPUC into the future.
Cordially,
Steven R. Ritchie
Assistant General Manager, Water
CC:
SFPUC: Dennis J. Herrera, General Manager; Ron Flynn, Deputy General Manager, SFPUC Commissioners
BAWSCA: Nicole Sandkulla, CEO; Tom Francis, Water Resources Manager