The US Bureau of Reclamation has awarded a $255 million construction contract to NW Construction for Phase 2 of the B.F. Sisk Safety of Dams Modification Project. The contract marks a key step in efforts to improve public safety and water supply reliability in California, US.
“Reclamation is committed to ensuring the safety and integrity of our water infrastructure,” said Acting Regional Director Adam Nickels. “This project represents a major investment in the future of California’s water supply and the communities and ecosystems that depend on it.”
B.F. Sisk Dam, located on the west side of the San Joaquin Valley, was built in 1967 and is part of both the Central Valley Project and State Water Project. It impounds San Luis Reservoir, the largest offstream reservoir in the country, and provides water to agricultural lands, communities, and wildlife refuges.
The 382-foot dam is in a seismic zone near the Ortigalita Fault. Reclamation’s Dam Safety Program identified risks and is taking corrective action under the 1978 Safety of Dams Act.
Phase 2 involves constructing a large stability berm along the central section of the 3.5-mile-long dam using about 15 million cubic yards of earthen material. The final phase will raise the dam’s crest by 10 feet. These measures are designed to reduce the risk of dam failure during an earthquake by preventing slumping and overtopping.
Phase 1, which included foundation preparation and initial berm construction, began in 2021 and was completed in 2024.
