Today marks the anniversary of the deadliest man-made disaster in California history. It’s a largely forgotten event which killed hundreds of people in Ventura County. On March 12th, 1928, the St. Francis Dam collapsed, sending a wall of water more than 50 miles from the Santa Clarita area through the Santa Clara River Valley. More than 400 people died. The water surged through parts of Piru, Fillmore, Santa Paula and Ventura in the middle of the night. It was later determined that the newly complete dam collapsed because of a combination of issues with the terrain, and design.