Minutes before midnight on the evening of March 12, 1928, the St. Francis Dam collapsed. The dam's 200-foot concrete wall crumpled, sending billions of gallons of raging flood waters down San Francisquito Canyon, sweeping 54 miles down the Santa Clara River to the sea, and claiming over 450 lives in the disaster. Captured here in over 200 images is a photographic record of the devastation caused by the flood, and the heroic efforts of residents and rescue workers.

Built by the City of Los Angeles' Bureau of Water Works and Supply, the failure of the St. Francis Dam on its first filling was the greatest American civil engineering failure of the 20th century. Beginning at dawn on the morning after the disaster, stunned local residents picked up their cameras to record the path of destruction, and professional photographers moved in to take images of the washed-out bridges, destroyed homes and buildings, Red Cross workers giving aid, and the massive clean-up that followed. The event was one of the worst disasters in California's history, second only to the San Francisco Earthquake and Fire.