Lake Mead’s Water Supply Has Dropped to the Lowest Level Since the Hoover Dam Was Built

A severe drought gripping parts of the western United States has caused Lake Mead’s water supply to dip to historically low levels this week, threatening a vital source of drinking water in a region that has been plagued by near continual drought conditions for decades.

Lake Mead — the massive reservoir formed by the Hoover Dam on the Colorado River — provides drinking water to Arizona, Nevada, and part of Mexico, and is also responsible for generating electricity for parts of Arizona, California and Nevada.

By Thursday, Bureau of Reclamation spokeswoman Patricia Aaron told CNN, Lake Mead’s water levels are poised to sink to below 1,080 feet above sea level — their lowest levels since the Dam was constructed in the 1930s.

“Lake Mead will most likely hit elevation 1,071.61 (feet) on Thursday, June 10,” Aaron said. “That will match the previous lowest elevation on record since the 1930s.”

The drop in water levels will also spell trouble for the dam’s potential electrical output: According to the Western Area Power Administration, the Hoover Dam typically generates about 2,074 megawatts of electricity, enough for nearly 8 million people to use. As of Tuesday, the dam’s capacity was at just 1,567 —about a 25% decrease.

And although Lake Mead’s levels are already at the lowest point they’ve been in measurable history, experts are anticipating that this is only the tip of the proverbial iceberg. According to Aaron, the lake’s elevation levels are expected to continue declining “until November 2021,” which will likely have devastating repercussions for the region’s water levels in the years ahead.

With that projected shortage in mind, officials are already planning to take the unprecedented step of declaring a Level 1 Shortage Condition for 2022 for Lake Mead in August — the month when operating conditions are typically set for the following year. The declaration will mean that the surrounding states will be forced to resort to water-saving measures that Tom Buschatzke, Arizona’s Department of Water Resources Director, told CNN were likely to be “painful.”

“While we may have less water coming to Arizona from the Colorado River in 2022, Arizona’s water managers and suppliers have been taking measures to prepare and will continue to work to ensure the river remains stable for generations to come,” Buschatzke added.

Climate change plays an undeniable role in the historic drought conditions, particularly when taken into account that many of the most recent years have been among the hottest on record. In March, the National Oceanic and Atmospheric Administration (NOAA) predicted that more than half the country would be susceptible to drought conditions in the coming months — a projection that has, sadly, borne fruit. A record heatwave is already baking California and large swaths of the western U.S., and a megadrought dogging the Southwest has prompted lawmakers to legislate against the implementation of “non-functional turf,” or any ornamental grass that will necessitate the use of dwindling water resources.