As the extreme drought gripping the American West enters its third year, water levels in Lake Mead, the largest man-made reservoir in the U.S., which supplies water to tens of millions of people, are at their lowest since the construction of the Hoover Dam in the 1930s.
During the past month, the water level in Lake Mead has continued to plummet, leaving it at roughly 30% of capacity and exposing the top of an old intake valve. At maximum capacity, the lake sits at 1,299 feet above sea level. On Wednesday it was measured 244 feet below that, at 1,055 feet above sea level.
On the same day, as a result of the lake’s falling water level, the Southern Nevada Water Authority activated a new low-lake-level pumping station completed in April so the state will continue to be able to supply residents with water.
"It's the worst it's ever been," Colby Pellegrino, deputy general manager of resources of the Southern Nevada Water Authority, told the Las Vegas Review-Journal this week regarding the ongoing drought.
This week, the Metropolitan Water District of Southern California issued restrictions on roughly 6 million customers that are set to begin on June 1 due to water shortages in Lake Mead and the Colorado River. The restrictions prohibit residents from watering lawns and plants more than one day per week.
As Yahoo News reported, the federal government declared its first-ever water shortage for the Colorado River in mid-August of last year, triggering cuts to the amount of water Arizona was able to draw from it. Since then, the situation has only gotten worse, with water levels dwindling at Lake Powell, another major reservoir on the Colorado River.
Last week, seven Western states that rely on the Colorado River for water agreed with a recommendation by the Department of the Interior requesting that they implement conservation measures like the ones put in place in Southern California. While states like Washington saw sufficient rainfall this winter to alleviate drought conditions, portions of states like Arizona, California, Nevada, New Mexico and Colorado continue to experience extreme drought.
"Not only is this drought continuing to chug along, it's proceeding at as full-steam pace as it ever has been," Parker Williams, a climate scientist at UCLA, told National Geographic.
Williams is an author of a new study published in Nature Climate Change that shows that warmer temperatures linked to excess greenhouse gas emissions have made the Western drought 40% more severe, and that the current drought will likely drag on through 2030.
With the drought expected to continue worsening as temperatures rise, water levels in Lake Mead are expected fall even further. The danger, according to the Southern Nevada Water Authority, is that if the lake's elevation falls below 895 feet, the "Hoover Dam can no longer release water downstream to California, Arizona, and Mexico."