Lake Mead, the largest reservoir in the United States, has fallen to its lowest level ever recorded, intensifying fears that the Southwest could soon face deeper water shortages and possible disruptions to hydroelectric power.
Created by the Hoover Dam on the Colorado River along the Nevada-Arizona border, Lake Mead was historically considered full at 1,220 feet above sea level. By Tuesday, its water level had slipped to just under 1,040 feet.
That steep decline, coupled with a similar drop at Glen Canyon Dam and its Colorado River-fed reservoir roughly 300 miles away, is raising the prospect that hydroelectric generation could soon be halted at both major facilities.
The US Bureau of Reclamation, which oversees federal dams and reservoirs, has warned that both dams are now only feet from levels that could force operators to stop their turbines. Those turbines help provide electricity to nearly two million people across Arizona, California, Colorado, New Mexico, Nevada, Nebraska, Wyoming and Utah.
The stakes extend far beyond power generation. As the Colorado River continues to shrink, as many as 30 to 40 million people could feel the impact because seven states depend on the river for drinking water, household use and agriculture.
Major cities including Las Vegas, Phoenix and Los Angeles, along with numerous smaller communities across the Southwest, draw a significant portion of their water from these reservoirs.
The worsening water crisis is being driven by extreme drought across the region, especially near the Colorado River’s headwaters in the Rocky Mountains. There, meager snowpack has left far less frozen water available to melt and flow downstream into the river system.
Conditions have grown so severe that the receding shorelines of Lake Mead and Lake Powell, the reservoir behind Glen Canyon Dam, are visible from passenger aircraft flying thousands of feet above the Southwest.
Pictured: Hoover Dam, which holds back the largest reservoir in the US, Lake Mead
The former water line in Lake Mead can be visibly seen from passenger planes flying over Arizona and Nevada
At Lake Mead, the power outage problem has already reached alarming levels. Lake Mead’s current water levels sit just five feet from hitting the point where older turbines at the hydroelectric facility will be forced to shut down to avoid damage.
Only newer ‘wide-head’ turbines can keep running at the lower water levels, however, this will lead to a sharp drop in power output.
The power coming out of Lake Mead at Hoover Dam serves over one million people across Arizona, California and Nevada. It generates about four billion kilowatt-hours of hydroelectric power each year.
Once the drought conditions drop those levels below 950 feet, the entire facility will have to shut down.
Lake Powell is just 30 feet away from dropping to the point where its hydroelectric turbines will need to shut down, adding another 300,000 people across the Great Plains and Southwest to the power crisis.
If the water in Lake Powell or Lake Mead drops too low for the dams to generate power, utilities that normally buy the cheap hydropower will have to scramble for replacement power from other sources.
Typically, this means more expensive natural gas or other options which can raise electricity bills for customers in the region and put further strain on the power grid – increasing the risk of a blackout in extreme conditions.
The water itself can still be released downstream through smaller pipes, but with less control and capacity, making it harder to manage supplies for cities to use in homes and farms to use for crops.
Lake Mead and Hoover Dam near capacity in 1983 (Left) compared to conditions in 2026 (Right)
US Bureau of Reclamation projections, released on July 15, show the iconic Lake Mead’s levels could likely drop by 33 feet over the next two years
JB Hamby, chairman of the Colorado River Board of California told the Associated Press: ‘It’s extremely significant and extremely concerning. You have three-quarters of the population of the Colorado River Basin, some 30 million people, who are directly impacted by risks to Lake Mead.’
A July report by the Bureau of Reclamation projected that the Lake Mead reservoir could drop by another 33 feet in the next two years. The reservoir is currently operating at less than 27 percent capacity.
One local, named John Belton, wrote online: ‘There’s only two things that can save Mead and Powell right now: 150 percent Colorado Rockies snow pack for five consecutive years, or God himself.’
Unfortunately, conditions are only predicted to worsen, especially this week, as a massive heat dome moves over the western half of the US.
AccuWeather has forecasted that high heat and humidity will combine to make states from Arkansas to California have a ‘feels like’ temperature near or surpassing 100 degrees Fahrenheit.
Higher temperatures increase evaporation and reduce runoff, meaning even less snowpack from the Rockies will make it to the Colorado River and replenish the region’s water supply.
Last month, the Bureau of Reclamation released a ten-year plan for how to operate Lake Powell and Lake Mead after the current rules expire at the end of 2026.
With the two lakes falling to record lows, the plan allows for mandatory water cuts, referred to as ‘shortages,’ across Arizona, California and Nevada.
The cuts were estimated to be up to 40 percent of what those states currently get from the reservoirs.
Hamby said: ‘The proposal responds to a fundamental reality: the Colorado River no longer reliably produces enough water to support all the uses and expectations built around it.’
