Being as I live in the area where the St Francis Dam disaster occurred, I decided to read it. For anyone who wonders how this disaster could have happened, this book tells the full story about Mulholland's life, his successes, and this major failure. It tells about the politics around water at the time of the dam. Of course, LA needed water. They didn't want anything to stand in the way, so based on Mulholland's earlier successes, they set it up so that Mulholland did the design AND he was the only one who could double-checked and certify his own design. Nobody else was allowed to review it or question it (ie, delay the project). Being self-taught, it turns out that Mulholland wasn't up on the most recent dam engineering. There wasn't any drainage for leakage under the dam. It was built on a seam between two different kinds of rock, one of which was mica. When the powers that be wanted the reservoir to hold more water, Mullholland simply added height to the dam without widening the base. This book is a somewhat technical read, but it's a well-written biography of Mullholand by his granddaughter, showing both the good and bad side. It's a part of our history.