Reducing Reliance on The Bay-Delta
The Sacramento-San Joaquin Bay-Delta is a network of islands and waterways at the confluence of the Sacramento and San Joaquin rivers east of San Francisco Bay. The Bay-Delta is also the hub of the State Water Project, a water storage and delivery system stretching over 700 miles from Lake Oroville in Butte County to its termination at Lake Perris in Riverside County. The State Water Project is owned by the State of California and operated by the California Department of Water Resources. Water from the Bay-Delta comes to the San Diego region via the State Water Project through the Metropolitan Water District of Southern California.
The Water Authority has a long history of supporting efforts to address the Bay-Delta’s complex environmental and water supply challenges. While water from the Bay-Delta is a critical resource for more than 25 million Californians, San Diego County is doing their part by reducing reliance on it.
Dig deeper, learn more
Bay Delta Fact Sheet
California Department of Water Resources Site
Water Resilience Portfolio
The Water Authority’s only source of Bay-Delta water is through its water purchases from MWD, which have decreased over the past three decades through the Water Authority and its member agencies’ long-term efforts to diversify the region’s water supply portfolio. Today, the San Diego region receives very little water from the Bay-Delta and will continue to reduce its reliance on it. Reducing pressure on the Bay-Delta aligns with state law designed to balance the environmental and water supply functions of the estuary.
Delta Reform Act
The Water Authority supported the 2009 Delta Reform Act, which established the state’s co-equal goals of water supply reliability and ecosystem restoration in the Bay-Delta. The Delta Reform Act made reducing dependence on the Bay-Delta while improving regional self-sufficiency an imperative, but the Water Authority began implementing these actions many years before they were required by state law. The San Diego region has since significantly increased its water use efficiency ethic.
Executive Order N-10-19
In April 2019, Governor Gavin Newsom issued Executive Order N-10-19, directing his administration to “identify and assess a suite of complementary actions to ensure safe and resilient water supplies, flood protection and healthy waterways for the state’s communities, economy and environment.” Newsom then directed state agencies to scrap the previous administration’s plans for a twin-tunnel project in the Bay-Delta in favor of a one-tunnel system.
Board Support
In July 2019, the Water Authority’s Board of Directors unanimously supported Governor Gavin Newsom’s efforts to develop a water resilience portfolio approach that meets the needs of California’s communities, economy and environment through the 21st century. In addition to focusing on multi-benefit approaches that meet many needs at once, the portfolio advances a single-tunnel project to transfer water across the Bay-Delta. The Water Authority Board supports the single-tunnel proposal contingent on a project financing plan that treats San Diego County ratepayers fairly through the proper allocation of project costs as supply charges.
A Vision Since 2013
Recognizing its importance, the Water Authority has a long history engaging in assessments of a variety of potential solutions to complex ecological and water supply issues in the Bay-Delta. Newsom’s portfolio approach is similar to a proposal the Water Authority, along with several water districts statewide, the Natural Resources Defense Council and other conservation groups proposed as a Portfolio Alternative for the Bay-Delta in 2013. That proposal included a single tunnel, new water storage south of the Delta and significant investments in local and regional water supplies.
Related Documents
Water Authority Letters & Responses
Water Authority Comments on the Negotiations for a SWP Contract Amendment for Delta Conveyance – August 7, 2019
Water Authority Board Chair to Gov. Newsom: Executive Order N-10-19/California Water Solutions – May 6, 2019
Water Authority Comments on Draft EIR for the SWP Supply Contract Amendments for Water Management and California WaterFix – December 7, 2018
Water Authority Deferral of Joint Legislative Budget Committee Hearing on SWP Contract Letter – July 31, 2018
Water Authority Amendment of SWP Contract for California WaterFix Letter – June 11, 2018
Water Authority Responds to State’s Bay-Delta Claims – Nov. 2016
Water Authority Amendment of SWP Contract for California WaterFix Letter – June 11, 2018 Water Authority to Secretary Laird, Nov. 15, 2016
Water Authority BDCP/WaterFix Comment Letter – Oct. 30, 2015
Water Authority BDCP Draft EIR/EIS Comment Letter – July 28, 2014
Water Authority BDCP Cost Allocation Letter – June 27, 2014
Water Authority BDCP Comment Letter – May 30, 2014
Water Authority BDCP Funding and Financing Letter – Feb. 5, 2014
Water Authority BDCP Analysis Letter – Oct. 7, 2013
Water Authority BDCP Presentation and Questions Letter – Sept. 4, 2013
Water Authority BDCP Draft Chapter 8 Letter – July 30, 2013
NRDC Portfolio Alternative – Jan. 16, 2013
Urban Agency Letter, Jan. 16, 2013
Bay-Delta & Project Policy Principles
Board Memos & Presentations
2023 Board Meetings
Memo: Bay-Delta Update – October 2023
Presentation: Bay-Delta Update – October 2023
2022 Board Meetings
Memo: Bay-Delta Update – November 2022
Presentation: Bay-Delta Update – November 2022
Memo: Bay-Delta Watershed Voluntary Agreements – July 2022
Presentation: Bay-Delta Watershed Voluntary Agreements – July 2022
Memo: MWD’s State Water Project Exclusive Areas – April 2022
Presentation: MWD’s State Water Project Exclusive Areas – April 2022
2021 Board Meetings
Memo: Bay-Delta Update – October 2021
Presentation: Bay-Delta Update – October 2021
Memo: Bay-Delta Update – January 2021
Presentation: Bay-Delta Update – January 2021
2020 Board Meetings
Memo: Bay-Delta Update – April 2020
Water Authority comment letter on draft Water Resilience Portfolio – February 6, 2020
2019 Board Meetings