CLARK COUNTY, Nevada: The reservoir created by the mighty Hoover Dam has fallen to its lowest level ever, as the U.S. West struggles during an extreme drought.

Lake Mead, created by Hoover Dam in the 1930s from the damming of the Colorado River at the Nevada-Arizona border, provides water to 25 million people in the cities of Los Angeles, San Diego, Phoenix, Tucson and Las Vegas.

However, due to the drought the lake surface now sits at 1,071.56 feet above sea level, a decline of 140 feet since 2000.

The drought has also struck California, the Pacific Northwest, the Great Basin spanning Nevada, Oregon and Utah, plus the southwestern states of Arizona and New Mexico and even extending into the Northern Plains.

The drought is so severe that farmers are allowing crops to perish, Nevada is banning the watering of about one-third of the lawns in the Las Vegas area, and the governor of Utah has called on the public to pray for rain.

Droughts are a recurring natural hazard in the American west. The current drought has lasted 22 years, the driest period in 115 years of record-keeping by the U.S. Bureau of Reclamation, which manages water resources in the Western states.

“In some states, especially parts of California and the southwest, these are really quite extreme drought conditions,” said Ben Cook, a climate scientist at NASA’s Goddard Institute for Space Studies.