Abstract.

This field trip guidebook has been assembled to assist readers in understanding the events surrounding the catastrophic failure of the St. Francis Dam in March 1928 and the enormous impact this tragedy had on America, giving birth to the practice of engineering geology in California, professional registration for engineers, creation of a state agency for assessment of dam and reservoir safety, and a host of other outcomes too numerous to mention here. The flood that resulted from the dam’s untimely failure killed more than 432 people, making it the worst man-caused disaster in America during the 20th Century. The forensic work on the St. Francis Dam failure illustrates the complex and interdisciplinary nature of working with earth, water, and structural systems, and conveys the frailties engineers and geologists possess, based on the limitations of their training and professional experience. All of us should read and digest the contents of this guidebook with great interest because none of us are above making many of the same mistakes, should we find ourselves in similar predicaments someday.