Rachel Ramirez, Pedram Javaheri and Drew Kann
The United States' largest reservoir is draining rapidly. Plagued by extreme, climate change-fueled drought and increasing demand for water, Lake Mead on Wednesday registered its lowest level on record since the reservoir was filled in the 1930s.
Lake Mead, a Colorado River reservoir just east of Las Vegas on the Nevada-Arizona border, is poised to become the focal point of one of the country's most significant climate crises: water shortages in the West. Millions of people will be affected in the coming years and decades by the Colorado River shortage alone, researchers say, with some being forced to make painful water cuts.
It's not a threat on the horizon; new projections show the first-ever water shortage along the Colorado River is all but certain to be declared later this year.
"Even without climate change, we would have a problem because we're taking more water out than the river could provide," John Fleck, director of the Water Resources Program at the University of New Mexico, told CNN. "But climate change has made the problem much worse by substantially reducing the flow in the river."
Lake Mead is around 143 feet below 'full,' a deficit roughly the height of the Statue of Liberty
The water in Lake Mead on Wednesday reached a new low — 1070.6 feet above sea level — since it was filled in the 1930's, according to data provided by the US Bureau of Reclamation. More precisely, every day for the past eight days has been a record as rapid evaporation and human use siphon water from the reservoir.
The lake has fallen around 143 feet below its 2000 level, when it was last considered full. What's left is a "bathtub ring" of white minerals as tall as Lady Liberty along the lake's steep shoreline.
25,000,000 people rely on Lake Mead water
That's more than the population of Florida.
Among the hardest hit in the first round of water cuts will be agricultural communities, particularly those in central Arizona. With less water, farmers say they will be forced to fallow land.
Native American communities are also impacted, Fleck said: "A number of tribal communities across the Colorado River Basin have been promised some water that they don't have yet."
The last time Lake Mead was considered full was 2000
Twenty one years ago Lake Mead peaked at an elevation of 1,214 feet. The highest recorded level was in 1983 when it was 1,225 feet above sea level.
Experts say it may never be full again. Lake Mead is now at 36 percent capacity — a number that will continue to fall as the reservoir's rapid decline continues to outpace projections from just a few months earlier. Water levels are projected to drop another 20 feet by 2022.
"This [rapid decline] scares me," said Fleck. "It's dropping so fast that it may be overreaching our ability to cope with the problems. I did not anticipate the bottom to drop this quickly, and we're only talking about Lake Mead."
Lake Mead has lost 5.5 trillion gallons of water since then
That is more than 1,000 Olympic-sized swimming pools lost every day for nearly 22 years.
When Fleck visited Lake Mead 10 years ago it was 13 feet higher than the current level. Even then, he recalled being terrified by the rapid water loss.
He visited every year since then and has seen the physical changes around Lake Mead firsthand. The "bathtub ring" is a visible reminder of where the water levels once peaked.
Hoover Dam power generation is down 25 percent due to low water levels
The Hoover Dam, which forms the Lake Mead reservoir, produces about 2,000 megawatts of hydropower — enough electricity for nearly 8 million Americans.
If the lake loses another 175 feet, water will no longer flow through the Hoover Dam
Experts say the "dead pool" level is at 895 feet, at which point water no longer passes through the Hoover Dam, thus cutting it off for everyone downstream.
"What we need to do is recognize the science behind this reality and that this does not get better," Fleck said. "We're all going to have to deal with less and collaborate on a new set of numbers that reflects the reality of the science today."
90 percent of Las Vegas's water comes from Lake Mead
Las Vegas has been preparing for the worst-case scenario for years. The city draws water from two underwater intake structures near the western shore of the lake. But they are becoming unusable as the water level drops beneath them.
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