Federal officials are taking unprecedented steps to protect the already record-low levels of water flowing through the Colorado River, as a megadrought fueled by climate change continues to threaten the water supply of more than 40 million people and about 5 million acres of farmland. The water level at one reservoir has dropped so low that, if it falls any further, it will no longer be able to produce electricity for some 6 million people across seven states.
That’s why, on Tuesday, the Interior Department announced it was delaying its plan to release 480,000 acre-feet of water from Lake Powell, the second-largest reservoir in the country. Powell’s water level currently sits at just 3,522 feet of elevation, and the Glen Canyon Dam requires water to be at 3,490 feet to spin its turbines and produce power. Officials said they will also release an additional 500,000 acre-feet of water into Lake Powell this year from the Flaming Gorge Reservoir, which sits upstream on the Wyoming-Utah border.
“We have never taken this step before in the Colorado Basin,” Tanya Trujillo, assistant Interior Department secretary, said at a Tuesday press conference. “But the conditions we see today, and what we see on the horizon, demand that we take prompt action.”
Officials believe those actions will keep water levels high enough to generate electricity for at least another year, saying that while not a permanent fix, the decisions are necessary to mitigate the immediate threats. Altogether, those moves should provide about a million acre-feet of additional water in Lake Powell. That is about 15 percent of the lake’s current volume and is equivalent to the annual amount used by more than 2 million households.
Other key reservoirs are struggling to maintain their water levels as well. Last August, the Bureau of Reclamation declared a water shortage for the first time in Lake Mead, the largest reservoir in the country, which is formed by the Hoover Dam in the Lower Colorado River Basin. Since Lake Mead receives its water supply from Lake Powell, Tuesday’s decisions could result in Mead’s water levels dropping even further.
The Colorado River originates from melting snowpack on the southern Rocky Mountains, which then flows 1,450 miles southwest to Mexico and the Gulf of California. But thinner snowpacks, declining precipitation and increasing temperatures from climate change have led to a prolonged drought in the West that has lasted more than two decades, posing a risk for water security throughout the Southwest.
The river’s flow has declined at least 20 percent since 2000 and is expected to decline more than 9 percent for every degree Celsius of warming, according to the U.S. Geological Survey.
The ongoing drought conditions in the West are causing especially severe problems for Southwestern states. Paired with harsh winds, the dry spell has exacerbated an early-onset wildfire season that’s terrorizing New Mexico and forcing thousands of people to flee their homes. And in a highly ambitious move, Arizona officials are proposing to help Mexico take the salt out of seawater in an attempt to safeguard the state’s share of the Colorado River, ICN’s Aydali Campa reported in March.
Arizona Gov. Doug Ducey proposed an investment of $1.16 billion over the next three years to advance that plan, which aims to build two desalination plants in Puerto Penasco, a Mexican city more than 60 miles south of the U.S.-Mexico border. Seawater would be pumped from the Gulf of California, also known as the Sea of Cortez, between the peninsula of Baja California and the Mexican mainland to the plants in the state of Sonora.
After the salt is removed, the water would be delivered to the Morelos Dam on the U.S.-Mexico border, where Colorado River water is distributed south of the border. With the freshwater satisfying U.S. commitments from the Colorado River to Mexico, more of the river’s flow could be held back for use in Arizona.
The plan is a risky one, with some experts saying it will cost far more money and require more energy than officials may think. One report estimated that the two plants could cost more than $3 billion to build and have annual operating costs as high as $119 million.
Sharon Megdal, director of the University of Arizona Water Resources Research Center, said that states will most likely require a broad suite of different solutions, as imperfect as they are, to address the worsening water shortages. “There aren’t necessarily quick fixes,” she said. “There aren’t necessarily cheap fixes.”
That’s it this week for Today’s Climate. Thanks for reading, and I’ll be back in your inbox on Tuesday.
1.8 degrees Celsius
That’s the amount of warming the International Energy Agency said the world would reach by 2100 if every country meets their climate pledges on time. It’s also the target climate envoy John Kerry pointed to in a recent speech, suggesting the U.S. could be softening its climate goals.