The Water and Life Museums are born of the construction of Diamond Valley Lake (DVL), the largest man-made water storage lake in North America. Set in the semi-arid Southern California desert near Hemet, DVL is an integral part of the state's water infrastructure. The lake provides a 6-month emergency supply of water for all of Southern California. Diamond Valley existed between 2 mountain ranges. Diamond Valley Lake was created by damming the Valley's open ends with two 300' high dams. The East Dam is 2.5 miles long. The Dam, is made from rock mined from these mountains. The Museums sit near the base of the East Dam of DVL. The construction of these dams is the largest earthwork project in American history.