Dam Failure Case Study: Folsom Dam (California, 1995)

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Located approximately 20 miles northeast of Sacramento, California, Folsom Dam was designed and constructed by the U.S. Army Corps of Engineers to generate hydropower along the American River. The 340-foot high concrete gravity Folsom Dam along with two earthen wing dikes on each of its sides create Folsom Lake. The spillway system at Folsom Dam allows the draining of Folsom Lake to maintain flow in the American River during routine maintenance and shutdowns at the power plant and in case of emergency. The spillway consists of eight 42-foot-wide bays equipped with five 50-foot-high radial service gates as well as three 53-foot-high radial emergency gates that release water from the reservoir. At the time of construction, which occurred between 1948 and 1956, Folsom Dam and Folsom Lake were part of a larger hydropower, irrigation, and water supply initiative called the Folsom Project. The Folsom Project also included the construction of a second dam approximately 7 miles downstream known as Nimbus Dam.