Colorado River drought: A US climate disaster to be handled legally


The Colorado River drought is the first climate disaster the U.S. legally has to deal with

The Colorado River is dying. The water source for 40 million people across seven states and part of Mexico is rapidly drying out, leaving the two biggest reservoirs in the U.S. thirstier and thirstier, and offering up what may be the first climate change impact that the country literally cannot ignore.

“We really don’t have a choice to fail on this,” said Christopher Kuzdas, a senior water program manager with the Environmental Defense Fund. “We’ve got to come together and find a way to manage and govern the system differently under climate change or there’s going to be catastrophic consequences for the Southwest, and I’m not overstating that.”

It’s also one of the rare climate disasters that government officials will be legally required to address if current trends continue. The Supreme Court just limited the Environmental Protection Agency’s ability to regulate emissions from power plants, and President Joe Biden’s legislative climate agenda remains stalled out in an obdurate Congress. But the 1922 agreement that governs use of the Colorado along with more recent legal plans made to address diminishing resources mandate water usage cuts as river flow and lake levels fall.

In 2000, Lakes Mead and Powell, the two huge reservoirs along the Colorado, were about 95 percent full. By the end of this year, Lake Mead is projected to be 27 percent full, with a water level 45 feet lower than it was only two years ago; for Lake Powell, the number is 22 percent, and its surface is 70 feet below the same time in 2020. The so-called Millennium Drought, now in its 23rd year, has reduced precipitation and snow runoff into the river and lakes so dramatically that a true water catastrophe now looms for an enormous chunk of the country.


The scale of the disaster is visible along the shores of Lake Mead, where a white “bathtub ring” reveals where water used to be. Minerals deposited when water levels were higher have turned these areas white, in contrast to the otherwise brown rock face. As water levels have dropped, the lake is revealing some morbid secrets — cars that plunged off cliffs and even bodies stuffed into barrels, raising decades-old questions surrounding mob bosses and murders.

Enormous cuts on the horizon

The ongoing drought has already led to some drastic water conservation measures, but it isn’t enough: In June, the Bureau of Reclamation’s commissioner instructed the seven states that rely on the Colorado’s water to make a plan to reduce use by between 2 and 4 million acre-feet over the next year — enough to cover all of Connecticut in a foot of water, with almost enough to add Rhode Island as well. And they have until only mid-August to get a deal done before the federal government will step in and dictate the cuts itself.

“Two to four is a big number,” said Jack Schmidt, a professor at Utah State University and director of the Center for Colorado River Studies. “And to come up with a plan in 60 days when you have diverse interests, ranging from Wyoming to California, is a huge challenge, given that the system is so near teetering on the edge at the bottom of the barrel.”

And even stricter cuts may be coming. If water levels at Lake Mead stay below 1,050 feet of elevation, where they are now, that would legally trigger a new level of restrictions in Arizona, Nevada, Mexico and likely California, beginning Jan. 1, 2023.

Over the longer term, the scale of the challenge is still menacing. In a new paper in the journal Science, Schmidt and his colleagues modeled out various scenarios for reducing use. They found that the sorts of concessions required in order to stabilize the river and the reservoirs “may seem unthinkable” — but nevertheless, those changes are necessary and must happen soon.


A dated legal framework

Kuzdas stressed that while climate change has brought the issue to a head, the catastrophe facing the Colorado is self-inflicted and dates to well before the modern era of climate science. The use of its water is based on a series of agreements, laws and treaties, collectively known as the Law of the River, largely negotiated more than a century ago. The Colorado River Compact, agreed upon in 1922, is the central document, a sort of original sin for water misuse.

“These laws and policies were set up in a completely different time,” Kuzdas said. “And they don’t reflect our values.”

The negotiations did not include the 30 tribal nations that live in the river’s basin, and they took place during a particularly wet period not yet parched by the changing climate. In fact, the river flooded more than once in the early part of the 20th century, causing widespread damage and sending a message that the water was apparently plentiful, but tree-ring studies have subsequently demonstrated that the early 1900s were as wet a period as the river has seen dating back to at least the 1500s.

The compact divided the water between an upper and a lower basin, with both allowed 7.5 million acre-feet per year of water; a subsequent treaty with Mexico granted the country 1.5 million acre-feet as well. Divergent development paths of the two basins have rendered that equal appropriation laughably dated, with the lower basin and Mexico traditionally using their full allocations while the upper basin did not come close. Recent agreements have already required reductions to the allocations, but with the drought persisting, it is not nearly enough to keep the water flowing.

“It’s a crisis that has been a long time in the making,” said John Fleck, a professor of practice in water policy and governance at the University of New Mexico and writer in residence at the university’s Utton Center. “We over-allocated the river a century ago, then had a whole bunch of communities make good-faith decisions to build cities and farms in the desert based on the promise of water that wouldn’t have been there in the long run, even without climate change. And climate change has just made that problem worse.”

Stabilizing pathways

The Bureau of Reclamation’s required cuts of up to 4 million acre-feet is a stopgap measure, intended to only address water shortages in 2023. Beyond that, new guidelines must also be developed to govern water use after 2026. Schmidt and his colleagues did offer up some potential solutions that would theoretically stabilize the river in the face of continuing drought conditions. One such scenario would involve capping upper basin use at 4.5 million acre-feet per year, while the lower basin and Mexico cut their usage by 3 million acre-feet; that would put both basins at around 67 percent of their original allocation.

But Schmidt told Grid that even that sort of scenario has risks, since their analysis basically assumed the present conditions remain — but they are likely to get worse. “The atmosphere is going to keep getting warmer, which means the flow is going to keep getting less, which means the amount of cuts have to keep going down even more,” he said.

Experts agree that basically all sectors will have to make some concessions, but with 70 to 80 percent of all the water used going to agriculture, it is clear where the bulk of the reduction in use will have to come from. And while there is a very obvious requirement — both legally and practically — to come to an agreement to stabilize the river and its reservoirs, no one seems quite prepared to offer up the needed cuts just yet. In a sense, it mirrors international climate change negotiations.

“Nobody wants to be the ones raising their hand and saying, ‘I’ll agree to cut back,’ and everybody else will say, ‘Thanks a lot,’” said Fleck, who has written two books about the Colorado and water issues in the West. What sets off the issue from that of emissions cuts is that at some point, the water simply runs out.

“And then there’s no choice,” Schmidt said. Failure, in this case, is essentially not an option.


When asked to describe what might happen if the new negotiations did fail, Kuzdas laughed. “You’re asking me to describe dystopia,” he said, before offering one way to visualize the outcome. “If we don’t get this right, we’re talking about no water flowing through the Grand Canyon.”

The requirements set forth by the Law of the River mean that a deal for 2023, and for beyond, is still a likely outcome, though the task is immense.

“I am pessimistic because climate change is coming at us so quickly that it is outpacing the tools of collaboration and negotiation and cooperation that we have so carefully developed,” Fleck said. “The risk is this devolves into chaos.”

Thanks to Lillian Barkley for copy editing this article.

  • Dave Levitan
    Dave Levitan

    Climate Reporter

    Dave Levitan is a climate reporter for Grid where he focuses on interconnected stories about climate and science, and politics shaping action around both.