Running water is often taken for granted. Thirsty? Grab a glass and turn on the tap. But the delivery of safe drinking water across mountains and desert to millions of Southern California residents isn’t as easy at it seems. The Las Virgenes Municipal Water District serves 75,000 customers in Agoura Hills, Calabasas, Hidden Hills and Westlake Village, as well as unincorporated areas of western Los Angeles County. But LVMWD is just the middle man. The district buys 100 percent of its drinking water from the Metropolitan Water District, which supplies water districts from Oxnard to the Mexican border. MWD supplies water to 25 million Californians.