The lifeblood of greater Los Angeles runs through the Coachella Valley, coursing through a series of tunnels bored into the rugged foothills of the San Jacinto Mountains.

The 242-mile Colorado River Aqueduct — constructed from 1933 to 1941 by the Metropolitan Water District of Southern California — stretches from Parker Dam at the Arizona border to Lake Mathews in western Riverside County. Since June 1941, it’s provided water to millions of residents of Los Angeles and the surrounding counties.