Lake Mead, which supplies electrical power and drinking water to millions of people in the American southwest, is drying up. It could soon become a "dead pool" and stop flowing to Hoover Dam.
From ABC News:
The minimum surface elevation needed to generate power at the Hoover Dam is 1,050 feet, according to the U.S. Bureau of Reclamation. Anything below that is considered "inactive pool," and a "dead pool" exists at 895 feet in elevation. The water levels at Lake Mead measured at 1043.82 feet Thursday morning, records from the Bureau of Reclamation show, making it less than 150 feet away from becoming a dead pool.
