USACE to pause Isabella Dam water releases for routine inspection

U.S. Army Corps of Engineers Sacramento District
Published June 26, 2023
Aerial Photo of Isabella Dam, September 2022

An aerial view of the Isabella Dam Safety Modification Project in Lake Isabella, California, Sept. 14, 2022. From top to bottom, this view shows the auxiliary dam, labyrinth weir and emergency spillway, service spillway, and main dam, looking southeast. Crews with the U.S. Army Corps of Engineers Sacramento District are approaching completion of construction work on the project, which is designed to reduce flood risk for downstream communities including Bakersfield.

The U.S. Army Corps of Engineers Sacramento District will pause water releases from Isabella Dam’s outlet works on June 27 to conduct a routine inspection of the conduit at the base of the dam following this year’s heightened reservoir inflows and subsequent releases.

From approximately 1-7 a.m. Tuesday, dam operators will gradually reduce water releases from Lake Isabella until the flow completely stops, which will allow the conduit inspection to begin. Upon completion of the routine inspection, which is estimated to take eight hours or less, releases of 500 cubic feet of water per second will resume and gradually increase until the outflow reaches the current target of approximately 5,300 cfs.

The entire process is expected to take approximately 24 hours and will add about 8,000 acre-feet of water to the reservoir’s storage.

Isabella Partners, which operates the hydropower plant at the base of the dam, notified USACE that they will also conduct an inspection of their plant while the water releases are paused. Questions regarding that inspection should be directed to Isabella Partners.

Activities in or around downstream waterways are strongly discouraged because currents are expected to fluctuate significantly, increasing danger for anyone in the water or along banks.

USACE continues to coordinate controlled water releases with local and state agencies to manage flood control space in our reservoirs and to help reduce the impacts of potential flooding. Our number one priority continues to be the life, health, and safety of the public.

For emergency information and planning resources, please visit:
Kern County Emergency Plans:
Kern County Emergency Alert Program:
California Governor’s Office of Emergency Services:

Ken Wright
916-502-2673 (cell)

Release no. 23-024