A water source for 40 million people is disappearing — and these NASA photos show it

Lake Mead is vanishing, and NASA has a front row seat.

It’s the largest reservoir in the U.S. and a crucial source of water and hydroelectric power. More than 40 million people depend on Lake Mead for water.

New satellite images from NASA show just how much Lake Mead has changed over the years, and experts say it’s troubling.

Lake Mead is shrinking — and it’s not stopping

Lake Mead has been shrinking for decades.

As of July 18, the water was at its lowest point since 1937. It’s sitting at 27% of its capacity.

Experts say the NASA images show how much the reservoir has changed. The new images show Lake Mead creating a “bathtub ring,” a phenomenon where there’s a light-colored outline where water used to be.

When the lake was at capacity, water would fill those areas. As the water started to disappear, however, the areas mineralized and dried up, leaving behind the “bathtub ring.”

What’s causing Lake Mead to disappear?

The simple answer is climate change, but there’s more to it.

A long-term drought that some have coined a “megadrought” has struck the western U.S. It’s the worst drought in 12 centuries, according to NASA.

Water levels in much of nine states throughout the West have faced “some level of drought,” according to NASA. About 35% of those states are experiencing “extreme” or “exceptional” drought.

Even so, only about 10% of the reservoir’s water comes from local precipitation and groundwater. Most of the water typically comes from snow melt in the Rocky Mountains.

That snow would melt, flow down to the Colorado River and through Lake Powell, Glen Canyon and the Grand Canyon. That’s not happening because snow has been much lower than average in several places, NASA said.

“In Colorado, location of the headwaters of the Colorado River, 83 percent of the state is now in drought, and the snowpack from last winter was below average in many places,” NASA said.

Who gets water from Lake Mead?

More than 40 million people use Lake Mead as a water source.

People in some of the country’s largest cities — including San Diego, Las Vegas, Phoenix and Los Angeles — get water and electric power from the Colorado River basin, which includes Lake Mead.

The water is also allocated to farmland. More than 5 million acres in the Southwest use water from the area.

Last year, the Bureau of Reclamation announced water allocations would be cut. Several states received less water than usual because of the drought.

”Given ongoing historic drought and low runoff conditions in the Colorado River Basin, downstream releases from Glen Canyon Dam and Hoover Dam will be reduced in 2022 due to declining reservoir levels,” the Bureau of Reclamation said in a news release. “In the Lower Basin the reductions represent the first ‘shortage’ declaration — demonstrating the severity of the drought and low reservoir conditions.”

Additionally, Lake Mead boaters have noticed changes. Five ramps at the reservoir have shut down because of low water levels. Only one boat launch remains.

“Declining water levels due to climate change and 20 years of ongoing drought have reshaped the park’s shorelines,” the National Park Service said on its website. “As Lake Mead continues to recede, extending launch ramps becomes more difficult and more expensive.”

Signs of a shrinking Lake Mead

While NASA’s new photos show how much Lake Mead has been shrinking, people have been noticing the low water levels on the ground as well.

In May, boaters discovered a body in a barrel at Lake Mead after hearing a woman scream from the side of the beach, McClatchy News reported. The body was found in an area that would’ve been about 100 feet underwater and hundreds of yards from shore decades ago.

Days later, a second set of human remains were discovered at Lake Mead.

More human remains found at Lake Mead days after body found in barrel, rangers say

Police told news outlets the remains could be the first of many to be uncovered by drought.

“I think anybody can understand there are probably more bodies that have been dumped in Lake Mead,” Las Vegas police Lt. Ray Spencer told KLAS. “It’s just a matter of, are we able to recover those?”

Tourists at Lake Mead also keep getting stuck in waist-deep mud as the drought uncovers fresh shoreline. Trucks and SUVs also got stopped in their paths.

“Newly exposed shoreline is dense and difficult to navigate,” Lake Mead rangers said May 23 on Twitter. “As a result, vehicles, vessels and people can get stuck.”

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