"LOS ANGELES — The St. Francis Dam was a proud symbol of California’s engineering might and elaborate water system — until just before midnight on March 12, 1928, when it collapsed, killing more than 400 people in a devastating wall of water. Ever since, the state has had a reputation of diligent inspections as it has built the largest network of major public dams in the nation.
But the threat of catastrophic flooding from the damaged Oroville Dam in Northern California this week — forcing the evacuation of nearly 200,000 people because of what environmental groups had asserted in 2005 was a design flaw — presented a warning sign for California, where a network of dams and waterways is suffering from age and stress. It also demonstrated that older dams may not be designed to deal with the severe weather patterns California has experienced because of global warming. The Oroville Dam was completed in 1968, toward the end of the golden era of dam building.
The culprit at Oroville was a faulty emergency spillway, used for the first time since the dam was opened after days of drenching storms, driven by what are known as atmospheric rivers, that filled the reservoir to capacity. But engineers and environmentalists said similar problems could occur at many of the roughly 1,500 dams that dot this state."