Diamond Valley Lake facilities tour
Posted by George J Janczyn on June 8, 2010
Diamond Valley Lake may sound like a faraway place to many San Diegans, but it isn’t that far and it’s an integral part of the regional infrastructure that provides San Diego with its water. The giant reservoir is located just south of Hemet, about an hour’s drive from San Diego. It was constructed to provide southwestern California with an emergency water source in case of a disruption in the Colorado River or State Water Project supply lines on the other side of the San Andreas Fault. As San Diegans are increasingly aware, around 90% of the city’s water is imported from those sources. I visited the area a few weeks ago during a water facilities tour; here are a few pictures (click pics for enlargment).
First is a photo of the Don Owen Dam, which is the west dam for the Diamond Valley Reservoir. The earth and rock fill dam is 1.9 miles long and 280 feet high. I took this picture from the Wadsworth Pumping Plant located at the foot of the dam:
The next shot is looking north from the top of the west dam. The white “bathtub ring” shows where the water level used to be when the reservoir was nearly full in 2006-07. The reservoir has a capacity of 810,000 acre feet, but as of April 2010 the reservoir contained less than 400,000 af:
Here’s a view of the western end of the lake, looking south:
The Wadsworth Pumping Plant has pumps and electric generators and works in two directions: it pumps water into the reservoir for storage, and when water is needed it is released through the plant’s generators to produce electricity.
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Burt Freeman said
Thanks, George, for the interesting commentary and splendid photos from the inspection tour hosted by the Water Authority. I too took the tour and would like to thank the Authority for their effort.
The Diamond Valley facility is truely impressive (and expensive), representing a link in the emergency water storage of San Diego. We shouldn’t feel entirely safe, however. Water supply interruption by earthquake or other natural or terrorist act could damage aqueducts and pipelines between Diamond Valley and San Diego water users. As postulated by the Authority’s Emergency Storage Project, an earthquake could take place on the Elsinore fault, for example, resuiting in several months interruption of imported water. Thus, the additional storage and interconnection facilities within our county being completed by the Authority.
While emergency storage is prudent and necessary, it does not eliminate our vulnerable dependence on imported water; we need the diversification of new, safe, local water supply. Seawater desalinated is our best bet.
George said
Burt, thanks for mentioning the tour hosts which I should have acknowledged in the post: I too am grateful to the Metropolitan Water District of Southern California which hosted and San Diego County Water Authority which co-sponsored this interesting and informative tour.