St. Francis Dam: Collapse and flood wave (en.wikipedia.org)

I can recommend John Wilkman's Floodpath: The Deadliest Man-Made Disaster of 20th-Century America and the Making of Modern Los Angeles, cited as "further reading" at the end of this article. I'd never heard of the St. Francis Dam disaster before reading it, and it's a good popular history-style look at the event.