Testing the San Gabriel Dam

Mark Pestrella, deputy director of the Los Angeles County Department of Public Works, standing on a catwalk just a few yards from water bursting out of a 123-inch-diameter valve at the San Gabriel Dam, only half-joking says of elected officials who attend the spectacular biannual valve tests: “Once they’ve seen this up close, they never vote ‘no’ on our projects.” See full story  (Irfan Khan / Los Angeles Times)

Engineers from the Los Angeles County Department of Public Works, which operates the L.A. County Flood Control District, watch as a torrent of water explodes out of a valve at the San Gabriel Dam along California 39. See full story  (Irfan Khan / Los Angeles Times)

San Gabriel Dam operator Herbert Romero turns a cast-iron wheel to open one of the earth-and-rock dam’s two 123-inch-diameter valves. Soon the ground rumbled and water blasted forth with a roar in a horizontal stream more than 200 feet long, as if from a mammoth rocket engine. See full story  (Irfan Khan / Los Angeles Times)

Torrents of water laden with sediment released during the valve test gushed out to a concrete spillway below and then churned a mile down the San Gabriel Canyon to the Morris Dam, a facility that President Hoover dedicated in honor of Los Angeles consulting engineer Sam Morris in 1934. See full story  (Irfan Khan / Los Angeles Times)