Although the Bureau of Reclamation and the California Department of Water Resources (DWR) are still several months away from holding public meetings to further inform the public of the dam safety project at B.F. Sisk Dam and San Luis Reservoir, located between Los Banos and Gilroy. DWR operates the Reclamation-owned B.F. Sisk Dam and San Luis Reservoir and is the cost-share partner.
An updated analysis of the risk and potential consequences of a large earthquake in the area has prompted Reclamation and the state of California to partner on the dam safety project to reduce the risks associated with a large seismic event. The plans call for adding stability berms and other physical features to the existing 3.5-mile-long earthen embankment.
The two agencies plan to hold public meetings in the spring to apprise the public of the plans for the seismic upgrades. Prior to the public meetings exploratory blasting to identify suitable material for construction of stability berms and other dam safety features will occur in the coming months. The public will be informed of the blasting prior to the work commencing, which will take place within Reclamation’s boundaries. Although the public may hear the blasting when it occurs it is not anticipated to impact the public or the environment. The public will be notified of any impact to recreation.
“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.”
“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.”
The off-stream San Luis Reservoir, located in Merced County, provides more than two-million acre-feet of combined supplemental storage capacity for the Central Valley Project and the State Water Project. The reservoir provides many benefits to the state and beyond including water for irrigation, municipal and industrial use, recreation and hydroelectric power.
A variety of risk reduction measures have been implemented as Reclamation 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.
The Record of Decision was prepared in accordance with the National Environmental Policy Act after completing thorough environmental review and public outreach and is available at: https://www.usbr.gov/mp/nepa/nepa_project_details.php?Project_ID=34281. Construction for the multi-year B.F. Sisk Dam and San Luis Reservoir project is expected to begin in summer of 2021.