A billion-dollar seimic upgrade project at B.F. Sisk Dam and San Luis Reservoir in California is to move forward, the US Bureau of Reclamation (USBR) and the California Department of Water Resources (DWR) have announced.

A dam safety project at the dam will see stability berms and other physical features added to the existing 3.5 mile-long earthen embankment in a bid to reduce the risks associated with a large seismic event. The work was given the green light following an updated analysis of the risk and potential consequences of a large earthquake in the area.

“This seismic upgrade project is part of our commitment to reduce the risk to downstream communities while protecting our valuable water supply,” said Ernest Conant, regional director for Reclamation’s California-Great Basin. “The strong partnership we share with the state allows us to leverage the expertise, resources and funding to ensure a safe and successful project.”

DWR operates the USBR-owned B.F. Sisk Dam and San Luis Reservoir and is the cost-share partner.

“We will continue to move forward with the important work to modernize infrastructure to protect California’s water supply and enhance public safety,” said acting State Water Project Deputy Director Ted Craddock. “This project represents a significant investment to address seismic risk to our water infrastructure.”

Additional risk reduction measures have been put in place at the dam as USBR works to put a more permanent dam safety project in place. These measures include heightened earthquake monitoring, real-time seismic monitoring, dam safety tabletop exercises with local responders, increased seismic inspection criteria and an updated dam emergency management plan.

Located in Merced County, the off-stream San Luis Reservoir provides more than 2 million acre-feet of combined supplemental storage capacity for the Central Valley Project and State Water Project. The reservoir provides many benefits to the nation, including water for irrigation, municipal and industrial use, recreation and hydroelectric power.
Construction on the multi-year project is slated to begin in summer of 2021.