News Release Archive

Reclamation and San Luis & Delta-Mendota Water Authority finalize plan to increase water storage in San Luis Reservoir

Project would produce additional water supply for 2 million people, over 1 million acres of farmland and 200,000 acres of Pacific Flyway wetlands

Media Contact: Mary Lee Knecht, 916-978-5100,
Scott Petersen, 209-597-0232,

For Release: December 18, 2020

San Luis Reservoir
San Luis Reservoir
SACRAMENTO, Calif. – Today, the Bureau of Reclamation and San Luis & Delta-Mendota Water Authority finalized the B.F. Sisk Dam Raise and Reservoir Expansion Project’s Supplemental Environmental Impact Statement/Environmental Impact Report. This joint proposed project would create an additional 130,000 acre-feet of storage space in San Luis Reservoir, producing additional water supply for 2 million people, over 1 million acres of farmland and 200,000 acres of Pacific Flyway wetlands. 

“Adding storage capacity to existing reservoirs is one of the most practical strategies for California’s water shortage,” said Commissioner Brenda Burman. “At San Luis Reservoir, we have an opportunity to meet two objectives at the same time: implement dam safety modifications and increase water storage. This is one of the most efficient water infrastructure projects we can make happen south-of-the Delta.”

B.F. Sisk Dam is a 382-foot high earthfill embankment located on the west side of the Central Valley, about 12 miles west of Los Banos. The dam is over 3 miles long and impounds San Luis Reservoir, which has a current total capacity of around 2 million acre-feet of water.

Reclamation and the San Luis & Delta-Mendota Water Authority partnered to investigate adding an additional 10 feet to the crest of B.F. Sisk Dam while implementing Safety of Dams modifications. The expanded space would store water that could be delivered to south-of-Delta water contractors and wildlife refuges. This water would meet existing contractual obligations and not serve any new demands.

“Growing demands for California’s shared water resources over the last century, combined with insufficient water storage capacity, limits our ability to meet customer needs,” said Regional Director Ernest Conant. “We are pleased to partner with the San Luis & Delta-Mendota Water Authority in this wise investment to increase the state’s water supply reliability.”

“San Luis Reservoir plays an important role as a lynchpin of California’s water system. The reservoir’s water storage capacity is increasingly important to respond to a changing climate. Increasing water storage is a critical component of building water resilience,” said Executive Director of the San Luis & Delta-Mendota Water Authority Federico Barajas. “We are glad to partner with Reclamation to investigate expanding San Luis Reservoir—increasing water storage capacity and improving multi-year water management for the urban and rural communities, ecosystems, and agricultural production that are reliant on water stored in San Luis Reservoir.”

View the combined final SEIS/EIR online at For document questions, contact Casey Arthur, Bureau of Reclamation, Willows Construction Office, 1140 W. Wood Street, Willows, CA 95988, at 530-892-6202 (TTY 1-800-877-8339), or

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