The Division of Safety of Dams came into existence as a direct result of one of California's worst catastrophes - the failure of the 2-year-old St. Francis Dam in Southern California one chilly night in March of 1928.

A wall of water, mud, trees, and boulders crashed down the San Francisquito Canyon into the Santa Clara River Valley on its 5 ½-hour rampage to the Pacific near Oxnard. The 70-foot wall of debris laid bare a 2-mile-wide swath 70 miles long, killed more than 450 people, left hundreds of others homeless, destroyed 900 houses, many bridges and roads, and 24,000 acres of farmland was swept away. In California's history, this event ranks second only to the San Francisco 1906 earthquake.

A state commission reported that the dam failed because it was ill-built in a geologically unstable site.

The failure of the St. Francis Dam prompted the State Legislature, on August 14, 1929, to create what is today the Division of Safety of Dams (DSOD), under the California Department of Water Resources.

Division engineers and engineering geologists review and approve plans and specifications for the design of dams and oversee their construction to insure compliance with the approved plans and specifications. Reviews include site geology, seismic setting, site investigations, construction material evaluation, dam stability, hydrology, hydraulics, and structural review of appurtenant structures. In addition, Division engineers inspect over 1200 dams on a yearly schedule to insure they are performing and being maintained in a safe manner.