Red Cross workers operate a hospital in Santa Paula following the St. Francis Dam disaster of March 12-13, 1928. Note the photographs tacked up above the cots. No doubt they're photos of missing persons, and the relief workers are keeping an eye out for them as people are brought in for medical care — just like the photos of missing persons that were displayed in New York City after the terrorist attacks of Sept. 11, 2001.

Construction on the 600-foot-long, 185-foot-high St. Francis Dam started in August 1924. With a 12.5-billion-gallon capacity, the reservoir began to fill with water on March 1, 1926. It was completed two months later.

At 11:57:30 p.m. on March 12, 1928, the dam failed, sending a 180-foot-high wall of water crashing down San Francisquito Canyon. An estimated 411 people lay dead by the time the floodwaters reached the Pacific Ocean south of Ventura 5½ hours later.

It was the second-worst disaster in California history, after the great San Francisco earthquake and fire of 1906, in terms of lives lost — and America's worst civil engineering failure of the 20th Century.