JOINT RELEASE: Reclamation and San Luis and Delta-Mendota Water Authority sign agreement that adds over 100,000 acre-feet of storage to San Luis Reservoir

The Bureau of Reclamation and the San Luis & Delta-Mendota Water Authority signed a cost share agreement for the B.F. Sisk Dam Raise and Reservoir Expansion Project, advancing water supply reliability in California’s Central Valley.

The joint project creates an additional 130,000 acre-feet of storage space in San Luis Reservoir, the nation’s largest off-stream reservoir, producing additional water supply for two million people, over one million acres of farmland and 135,000 acres of Pacific Flyway wetlands and critical wildlife habitat. This water would meet existing contractual obligations and not serve any new demands.

A $125 million investment in the project under the Bipartisan Infrastructure Law was announced earlier in January. Previous funding announcements include a $75 million investment announced in May 2024, a $10 million investment in July 2023, and a $25 million investment announced in October 2022. An additional $60 million was authorized for project construction from the Water Infrastructure Improvements for the Nation Act, for a total of $295 million in federal contributions to date in construction costs.

Previously, the Bipartisan Infrastructure Law provided over $100 million to the B.F. Sisk Dam for a separate but connected project that will increase the dam crest by 10 feet to improve seismic fortification.

“This exciting milestone represents forward momentum not only as it relates to increasing water storage capacity in the region, but also the collaborative relationship we have with our partners,” said Bureau of Reclamation Regional Director Karl Stock. “This increase in water storage capacity south-of-Delta in San Luis Reservoir will bolster our ability to enhance water reliability for California communities, agriculture, and wildlife.”

“San Luis Reservoir has served as the hub of California’s water system south of the Sacramento San Joaquin Bay-Delta since its completion in 1967, and we are proud to take the next step to improve it for current and future generations” said San Luis & Delta-Mendota Water Authority Board Chair Cannon Michael. “The future of California—in particular, the San Joaquin Valley—is dependent on our ability to improve the reliability of water supplies for our farms, communities, and wildlife refuges. This project advances our goal to improve our communities’ access to clean drinking water for residents, improve water reliability to continue to feed America, and to support the health of the habitat upon which our native species and migratory waterfowl on the Pacific Flyway depend. We value the funding contributions and working relationship with our federal partners in the Bureau of Reclamation and look forward to advancing this important water storage project.”

B.F. Sisk Dam is a 382-foot high earthfill embankment located on the west side of California’s Central Valley, about 12 miles west of Los Banos. The dam is over three miles long and impounds San Luis Reservoir, which has a current total capacity of around two million acre-feet of water. Visit https://www.usbr.gov/mp/sccao/sisk/index.html to learn more about B.F. Sisk Dam and San Luis Reservoir.