Walnut Canyon Reservoir

Walnut Canyon Reservoir is a 920-million-gallon reservoir that supplies water to Anaheim homes and businesses.

View of Walnut Canyon Reservoir and bluff with houses at top of bluff
Wide view of Walnut Canyon Reservoir with houses in the distance

Constructed in 1968, Walnut Canyon Reservoir and the adjacent dam have served the community for over to 50 years. 

Overhead shot of Walnut Canyon Reservoir
The reservoir receives deliveries of imported, untreated Colorado River Water from the Metropolitan Water District (MWD) of Southern California. Water from the reservoir is then treated at the August F. Lenain Treatment Plant prior to delivery to Anaheim Public Utilities' customers. The reservoir is capable of storing 920 million gallons of imported water, enough to supply the area for 30-45 days in the event of an interruption to imported supplies from MWD. It also offers operational flexibility to avoid imported water peaking charges during summer periods of extended hot weather and provides a valuable resource in helping to contain brush fires.

Quick Facts

A working water storage reservoir, it serves as a primary source of water to the Anaheim hill-and-canyon areas; which allows the City to manage short-term, emergency, and seasonal water supply needs.

This reservoir also provides the water for helicopter-based firefighting purposes.

The Walnut Canyon Reservoir is also historically significant. While the construction crew was restoring the concrete “A” monument, contractors found a handwritten letter inside, which was signed by the original City crew. This letter serves as a testament to the pride that City staff have long had in their work.