Increasing storage while maintaining dam safety
CDM Smith evaluated designs to raise the dam crest and increase storage capacity while maintaining the necessary freeboard to prevent overtopping during seismic deformation events.
Practices
Markets
Dam raise planning advances added storage and infrastructure upgrades
Concerns about seismic risk at B.F. Sisk Dam prompted federal and state agencies to pursue safety modifications to protect downstream communities. As part of that effort, the U.S. Bureau of Reclamation and the San Luis and Delta-Mendota Water Authority evaluated raising the dam embankment to also increase storage at San Luis Reservoir. With CDM Smith's support, the partners assessed the technical, environmental, and economic feasibility of the proposed expansion.
Delivering accelerated feasibility and review
We completed feasibility, environmental review, and cost-sharing analyses on an accelerated one-year schedule to meet WIIN Act funding deadlines.
Improving water supply reliability
CDM Smith evaluated potential improvements to water supply reliability for communities, agriculture and habitat by expanding reservoir storage capacity by more than 130,000 acre-feet.
Coordinating complex infrastructure interfaces
In parallel with Reclamation’s design for B.F. Sisk Dam, CDM Smith completed feasibility-level design and analysis for raising State Route 152, working closely with Caltrans to maintain roadway safety at higher reservoir water levels.
Through a partnership with SLDMWA and Reclamation, CDM Smith completed the studies and reports needed to support project implementation. Creating 130,000 acre-feet of new storage at the nation’s largest off-stream reservoir will improve access to water supplies for millions of people, agricultural lands, and critical Pacific Flyway habitat. Federal investments announced between 2022 and 2023 have advanced the project toward implementation, marking the first approval of a major California water storage project since 2011.