Briones Reservoir Inlet/Outlet Tower Retrofit

Project Overview

EBMUD completed the construction of retrofits to the Briones Reservoir inlet/outlet tower in August 2024. The tower is located in Briones Reservoir, an approximately 60,000 acre-foot raw water storage facility in unincorporated Contra Costa County to the north and east of the City of Orinda. Constructed in 1964, the tower is a concrete structure that is about 230 feet high, with an inside diameter that ranges from 20 feet at the base to 10 feet at the top.

The tower is located approximately 3.5 miles from the Hayward-Rogers Creek Fault, which is capable of generating a magnitude 7.25 earthquake. Seismic analyses showed that the tower would suffer significant damage when subject to a major seismic event, which could affect the ability of the Orinda Water Treatment Plant to obtain water from Briones Reservoir. In addition, the lower tower outlets could become blocked, preventing the reservoir from being drained. The retrofit included reinforcing the tower to improve seismic safety, installing a debris catcher to prevent outlets from becoming blocked, and installing remote valve controls for increased operational reliability.

Contact

Community Affairs
Email: construction-east@ebmud.com
Phone: 510-287-2053
For after-hours, call EBMUD at 866-403-2683

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