March 12, 1928 - Mulholland's Fault

A California engineer colleague tells me that this disaster led to the state engineer registration law. Also, the dam was in the San Fernando Valley east of LA. The Owens Valley is east of the Sierra Nevada. That's also a infamous source of LA water. CA architect

Sorry, the dam was not in the Owens Valley nor in the San Fernando Valley. It was in the Santa Clarita Valley, actually built across a narrow part of the San Francisquito Canyon, close to Castaic, Saugus and Newhall, California -- and now Valencia. I lived in Newhall from 1973 to 1980. The father of a college friend from Barstow, CA had lived in Newhall at the time of the dam collapse and was an eye witness to the devastation on the morning after. I interviewed the father (Robbie Dill) about the collapse, and drove up the canyon many times, passing large chunks of concrete debris still resting there (at that time). The water emptied into the Santa Clara River and flowed to the ocean passing the small towns of Piru, Fillmore and Santa Paula, which is alongside highway 126. The river empties into the ocean near Vantura. The elder Dill said that many people were worried about the dam, that weeks before water was spotted leaking out along the sides, increasing in volume by the day. Further up the canyon is a hydroelectric power plant also built about the same time, which generates power as in comes down the four large California Aquaduct pipes from much higher Mojave Desert and Owens Valley. It generates about 50 MW and initially supplied Los Angeles with about 30% of its electric power. I toured the power plant once around 1974, but don't know if it is still in operation, since 50 MW is trivial for the needs of present-day Southern California.