Los Vaqueros Reservoir Expansion OVerview

Expansion of Los Vaqueros Reservoir improves Bay Area water supply reliability and water quality while protecting Delta fisheries and providing additional Delta ecosystem benefits.

The proposed project will include a regional intertie (the Transfer-Bethany Pipeline), improved pump stations and pipelines and could increase the reservoir's capacity up to 275,000 acre-feet.

The proposed project builds upon the successful first phase of expansion from 100,000 to 160,000 acre-feet funded by the Contra Costa Water District and completed in 2012.

Los Vaqueros is one of the projects being evaluated in the context of a broader Bay Area effort to work collaboratively as a region to improve water supply reliability.

See what others are saying about the Los Vaqueros Expansion



"...Raising Los Vaqueros’ earthen dam by 55 feet has has drawn widespread support from both environmentalists and water agencies, including the Santa Clara Valley Water District and East Bay Municipal Utility District. It would provide storage for 275,000 acre feet of water, enough to meet the needs of an additional 575,000 people."
Mercury News & East Bay Times Editorial Boards
January 23, 2018


"Expanding Los Vaqueros Reservoir is an innovative project that embodies what the voters approved when they passed Proposition 1, including significant, well-defined public benefits for the environment."

George Miller, Member of Congress, Retired
August 9, 2017


"Working to expand water supplies for California’s next drought, a coalition of 12 Bay Area water agencies took a significant step Monday toward an $800 million expansion of one of the largest reservoirs in the Bay Area — Los Vaqueros Reservoir in the rolling hills near the Alameda-Contra Costa county line."
San Jose Mercury News
July 3, 2017


"Additional flexibility for the water-supply system, water to benefit urban customers in the Bay Area, water for wetlands as well as for farmers and other water users south of the delta: Those are the reasons a dozen partners have joined in support of a proposed expansion of Los Vaqueros Reservoir."


Ag Alert
June 28, 2017


"Millions of Bay Area residents could get extra drought insurance against water shortages and quality problems from a proposed $800 million expansion of the Los Vaqueros Reservoir that may have up to 10 water suppliers as partners."

East Bay Times
November 5, 2016


"...This plan is amazingly simple. The height of the earthen dam would be raised by 51 feet to 269 feet. That would enable Los Vaqueros Reservoir to expand its capacity from 160,000 acre-feet of water to hold 275,000 acre-feet enough to serve 1.4 million residents on an annual basis." 
San Jose Mercury News Editorial
April 28, 2016


Latest News

Statement on Initial Public Benefit Scores Provided by the California Water Commission

Jerry Brown

The District understands that California Water Commission (CWC) staff have some questions regarding the public benefit ratio for expanding Los Vaqueros Reservoir, primarily on a technical basis, which have led to CWC staff reducing the project’s public benefit ratio. This is the first step in a multi-step application process and we will work diligently to answer their questions. The District will be appealing the CWC staff adjustments and we remain confident that we can address the questions and demonstrate that expanding Los Vaqueros Reservoir will provide significant public benefits consistent with what voters approved in passing Proposition 1, so that the CWC will approve a final public benefit ratio that allows the project to qualify for state funding. All involved have the best interest of the state’s residents in mind and share the common goal of creating new storage that provides for the future needs of California.

Jerry Brown
General Manager
Contra Costa Water District