It was around midnight, 75 years ago tonight, that Southern California suffered one of the worst disasters in the state's history -- second only to the earthquake and fire that devastated San Francisco in 1906.
The St. Francis Dam in San Francisquito Canyon, about 50 miles north of Los Angeles, was intended to serve as a backup supply of water in case the flow of water from the Owens Valley was interrupted. Farmers and ranchers in the Owens Valley were battling the city over an aqueduct that drained their underground springs, and the city needed an alternative.
Construction of a new dam and reservoir began in 1924 under the supervision of famed engineer and Department of Water and Power chief William Mulholland. The reservoir held nearly 13 billion gallons of water -- enough to supply Los Angeles for an entire year.
But on March 12, 1928, half of the dam suddenly collapsed, sending a huge wall of water, mud and debris hurtling down the valley towards the Pacific Ocean, 54 miles away. At least 470 died -- no one is sure of the exact number -- and the disaster ended Mulholland's career.
NPR's Michele Norris talks with John Wilkman and his wife Nancy, who are working on the documentary film The Saint Francis Dam Disaster.
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