life after warming

‘We Woke Up and We Lost Half Our Water’

How climate change sparked a multistate battle over the Colorado River.

Photo: David McNew/Getty Images
Photo: David McNew/Getty Images

The Colorado River’s 1,450-mile run begins amid the snowy pinnacles of the Rocky Mountains and ends in the subtropical waters of the Gulf of California. Over the millions of years the river has been running this course, it has gradually carved through the Southwest’s crimson limestone and shale to create a succession of unimaginably vast canyons: Ruby, Cataract, Marble, and Grand. The writer Marc Reisner described the Colorado as the “American Nile.” The Hualapai call it Hakataya, “the backbone.”

Starting in the early 20th century, much of the Colorado’s natural majesty was corralled into a system of reservoirs, canals, and dams that now provides drinking water for 40 million people, irrigation for 5 million acres of farmland, and sufficient power to light up a city the size of Houston. Not so long ago, there was more than enough rainfall to keep this vast waterworks humming. The 1990s were unusually wet, allowing the Colorado to fill its two sprawling reservoirs, Lake Mead and Lake Powell, to 95 percent of capacity. By 2000, more than 17 trillion gallons of water were sloshing around in the reservoirs — more than enough to supply every household in the United States for a year.

Then the drought arrived. And never left. After the driest two-decade stretch in 12 centuries, both Mead and Powell fell below one-third of their capacity last year, throwing the Southwest into crisis. On January 1, mandatory cuts went into effect for the first time, forcing farmers in Arizona and the utility that provides water to metropolitan Las Vegas’s 2.3 million customers to limit their uptake from Lake Mead. Even with those cuts, Bill Hasencamp, a water manager from Southern California, says, “The reservoir is still going down, and it will stay low for the next several years. I don’t think we’ll ever not have a shortage going forward.”

If Hasencamp is right — and most scientists agree that America’s deserts will only get drier as the climate crisis worsens — that means he and other officials in the region have their work cut out for them to ensure that the Southwest stays hydrated. The Colorado River is currently governed by a set of operating guidelines that went into effect in 2007, the latest in a long line of agreements that began with the original Colorado River Compact in 1922. But that framework is set to expire in 2026, giving officials in the seven states through which the Colorado and its tributaries flow — along with their peers in Mexico and the 29 tribes whose ancestors have depended on the river for millennia — an alarmingly narrow window to come to a consensus on how to share a river that’s already flowing with one-fifth less water than it did in the 20th century.

The Southwest’s water managers have been working feverishly this spring just to prop up the system until formal negotiations can begin next winter. In March, the water level of Lake Powell declined below a threshold at which the Glen Canyon Dam’s ability to generate power becomes threatened, and the Bureau of Reclamation, the federal agency that oversees the West’s water infrastructure, is working with the states above Lake Powell to divert more water to keep its dam operational. Meanwhile, the states around Lake Mead have been hashing out the details of a plan to voluntarily curtail their use to prevent even more dramatic cuts to Arizona and Nevada from going into effect next year.

Poor hydrology isn’t the only thing on the water managers’ minds: They’re also contending with the yawning cultural and political chasm between the region’s urban and rural interests as well as questions about who should suffer the most aggressive cuts and how to better engage Indigenous communities that have historically been cut out of the dealmaking. All of that makes the Southwest’s deliberations over the Colorado River a window into how climate change is putting pressure on divisions embedded throughout American society.

Pat Tyrrell, Wyoming’s former state engineer, says if the states fail to reach an accord, “we’re looking at 20, 30 years in the court system.” That would be a nightmare scenario given how disastrous the past two decades have been for the river. Falling back on the existing framework of western law could result in hundreds of thousands of people being stranded without water or electricity — or, as John Entsminger of the Southern Nevada Water Authority puts it, “multiple Katrina-level events across southwestern cities.” The negotiations, then, represent the first major test of the American political system’s ability to collaboratively adapt to climate change. “I think the states feel a strong interest in working this thing through among ourselves so that we don’t end up there,” says Tyrrell. “We can’t end up there.”

Although the Colorado River is a single water system, the 1922 Colorado River Compact artificially divided the watershed in two. California, Nevada, and Arizona were designated the Lower Basin, while Wyoming, Colorado, New Mexico, and Utah were labeled the Upper Basin. Each group was awarded half of the river’s water, and a series of ensuing agreements divided that pot between the states in each basin according to their population and seniority. Mexico’s right to the Colorado took until 1944 to be enshrined, while each of the region’s 29 tribes had to fight for its entitlements in court. Every water allocation in the multitude of treaties and settlements that branch out from the original compact is quantified using the agricultural unit of an acre-foot, the amount of water it takes to flood an acre of land to a depth of one foot (a helpful rule of thumb is that one acre-foot is enough water to supply three households in the Southwest for one year).

The fundamental flaw of this compact is that it was signed at a time of unprecedented rain and snowfall in the basin, which led its original framers to assume that 15 million acre-feet of water flowed through the Colorado every year. In the 21st century, the annual average flow has been closer to 12 million acre-feet, even as much more continues to be diverted from Lake Mead and Lake Powell every year — that discrepancy helps to explain how the reservoirs have emptied so quickly. The other culprit is climate change.

In March, Bradley Udall, a water and climate researcher at Colorado State University, gave a presentation at the University of Utah’s Wallace Stegner Center that laid out several models for how much drier the basin could become by 2050, including an especially frightening forecast that the river may end up carrying 40 percent less water than it averaged during the 20th century. “There’s just a lot of worrisome signs here that these flows are going to go lower,” Udall says. Tanya Trujillo, who, as the assistant secretary for water and science at the Department of the Interior, is effectively the federal government’s top water official, agrees with that assessment. “The bottom line is we’re seeing declining storage in both Lake Mead and Lake Powell,” she says. “But we’re also seeing increasing risk of the system continuing to decline.”

The people tasked with managing that decline are the select groups of civil engineers and lawyers who populate the various state agencies and utilities that take Colorado River water and deliver it to municipal and agricultural users. Each state has what amounts to a delegation of water experts who are led by a “governor’s representative,” with the exception of California, which defers to the three massive irrigation districts in Imperial and Riverside counties as well as the Metropolitan Water District of Southern California, popularly known as Met, which provides for 19 million residents of Greater Los Angeles and San Diego.

Hasencamp has been with Met since 2001 and now serves as the utility’s point person on the Colorado. He’s a Californian with deep roots — he lives in the Glendale house his grandfather built in the 1930s. At the time, the L.A. suburb had nearly as many residents as the entire state of Nevada. The outsize influence of Los Angeles in the basin has made it a sort of water bogeyman over the years, an impression Hasencamp has had to tamp down. “You’re coming from Los Angeles, nobody trusts you,” he says, his ruddy face breaking into a sporting grin. “‘The big city slicker, coming here to steal our water to fill your swimming pools.’ You have to get over that hurdle. It takes a long time.”

Although he arrived at Met during a time of plenty, within a year the agency was scrambling to respond to the worst water year ever recorded in the Southwest. In 2002, the Colorado shrank to just 3.8 million acre-feet — one-quarter of the flow assumed in the compact. “In 2003, we woke up and we lost half our water,” Hasencamp says. “We had to scramble.” After a flurry of emergency measures, including paying farmers to fallow their fields so their water could be diverted, the state managed to reduce its use by 800,000 acre-feet in a single year and has managed to not surpass its 4.4 million acre-feet allotment ever since.

Now, the entire region is facing the sort of crisis California did in 2002 but with much less margin for error. While the explosive population growth of Arizona and Nevada originally put pressure on California to draw down its use in the 1990s, now the Upper Basin states of Utah and Colorado — each of which added over a half-million residents in the past decade — are adding strain to the system. Currently, the Upper Basin uses only about 4.5 million acre-feet of water every year, leaving roughly 2 million acre-feet that the four states are theoretically entitled to as they keep adding population.

As the chair of the recently formed Colorado River Authority of Utah, Gene Shawcroft serves as the state’s lead negotiator. He grew up on a ranch along the Alamosa River in southern Colorado and was riveted by the West’s vast plumbing network from an early age. “Christmas was okay, but the best day of the year was when they turned the irrigation water on,” he says. Although he otherwise carries all the hallmarks of the taciturn Westerner, talking about water can still make Shawcroft light up like a kid at the holidays. “We have to learn to live with very, very dry cycles, and I still believe we’re going to get some wet years,” he says. “That’s part of the fun. I’m thrilled to death we have infrastructure in place that allows us to use the water when it’s available.”

Utah has the right to use about 1.7 million acre-feet of water from the Colorado, but it cannot collect from Lake Powell (its major aqueduct, the Central Utah Project, connects only Salt Lake City with the river’s tributaries). Given Utah’s rapid growth, the state’s politics are increasingly revolving around the pursuit of more water. Late last year, Governor Spencer Cox gave an interview to the Deseret News in which he called the disinclination of many in the West to dam more rivers “an abomination,” and his office has pushed hard for a pipeline between Lake Powell and the city of St. George in the southwest corner of the state, about two hours from Las Vegas.

But pipelines and dams are useful only as long as there’s water to be stored and transported. That’s why Cox released a video last summer in which he told his constituents that the state needed “some divine intervention” to solve its problems. “By praying collaboratively and collectively, asking God or whatever higher power you believe in for more rain, we may be able to escape the deadliest aspects of the continuing drought.” The early returns from the pray-for-rain strategy have not been good, as this winter’s snowpack indicates that 2022 will be just as dry as 2021.

Shawcroft is more clear-eyed about Utah’s situation. (Cox’s office declined my interview request.) “The upper-division states for the last 20 years have been living with less water than what their allocations were simply because that’s what Mother Nature provided,” he says. “We’re not in a situation where we have this large reservoir sitting above us and we say, ‘Okay, this year we’re going to cut back. We’re going to take 70 percent, or 50 percent of 20 percent, or 99 percent.’” As he well knows from having grown up along the Alamosa, “we only get what comes through the streams.”

Despite those limitations, the Upper Basin has managed to divert more than 500,000 acre-feet to Lake Powell since last year, mostly by sending water downstream from a handful of smaller reservoirs on the Colorado’s tributaries. Although those transfers may keep Glen Canyon Dam running this year, they have severely limited the basin’s ability to respond if the level of Lake Powell keeps falling. Down in the Lower Basin, efforts have been focused on the so-called 500+ Plan, an agreement between California, Arizona, and Nevada to proactively cut their uptake from Lake Mead by 500,000 acre-feet this year and next in hopes of slowing its decline. While the states have managed to come up with about 400,000 acre-feet so far, many in the region are skeptical that the Lower Basin can do it again in 2023. Still, Entsminger, Nevada’s lead negotiator, sees the plan as a remarkable success story, particularly given how quickly it was implemented. “It’s like exercise,” he says. “You know what’s better than nothing? Anything.”

At the Stegner conference where Udall made his dire prediction, Entsminger shared that his agency is now planning for the annual flow of the Colorado to fall to just 11 million acre-feet. Given how squirrelly water officials can become when it’s time to talk about actual water, many in the room were taken aback that Entsminger would be willing to dial in on a projection so specific — and so low. Later on, Arizona’s lead negotiator, Tom Buschatzke, joked, “I won’t say I agree to 11. I might get arrested when I get off the plane in Phoenix.”

When I caught up with Entsminger a few days after the conference, he was matter-of-fact about the declaration. “The average of the last 20 years is 12.3 million acre-feet, right? If you’re saying from today to mid-century the average flow of the river only goes down another 10 percent, you’re lucky.” In some ways, Entsminger is an ideal messenger for this kind of reality check. Contrary to its reputation for wasting water on golf courses and the Bellagio’s fountains, Las Vegas has the most efficient water-recycling system in the United States. Entsminger’s utility has cut its intake from Lake Mead by 26 percent in the past two decades, a period that saw metropolitan Las Vegas add more residents than the population of Washington, D.C.

Although California and Arizona are in less enviable positions, officials in both states seem realistic about the need to reduce their water consumption. “If the last 30 years repeats itself, the Lower Basin will have to cut its use by about 1 million acre-feet,” says Hasencamp. “If the future’s dryer than it’s been the last 30 years, it could be 1.5, 2 million acre-feet.” Balancing the region’s accounts in the coming decades will mean adopting even more aggressive conservation and recycling measures as well as striking more fallowing deals with irrigation districts.

The Southwest’s tribes will play a pivotal role in these negotiations, as many are entitled to more water than they are able to use (that is, as long as they have been able to secure a water-rights settlement, which many are still in the process of pursuing). In 2019, the Gila River Indian Community, south of Phoenix, agreed to a deal with Arizona that saw some of its water directed to the state’s underground reserves and some left in Lake Mead, generating tens of millions of dollars in revenue for the tribe. This spring, Senator Mark Kelly introduced a bill in Congress that would allow the Colorado River Indian Tribes — a confederation of Hopi, Navajo, Mohave, and Chemehuevi peoples — to negotiate a lease with Arizona similar to what it has already signed with Met and the Palo Verde Irrigation District in California (the group’s reservation is split between the two states). I spoke with the tribe’s chair, Amelia Flores, shortly after she testified in support of the legislation on Capitol Hill. “Everybody has to be part of the solution,” she says. “It’s not just about one tribe or one water user; it has to be everyone to save the life of the river.”

Upstream, the commitment to everyone in the basin sharing the pain of the Colorado’s decline is less clear. “Right now, the Lower Basin uses over 10 million acre-feet a year, while the Upper Basin uses under 5 million acre-feet,” says Rebecca Mitchell, director of the Colorado Water Conservation Board. “Do we take additional hits because the Lower Basin has become reliant? They’re not just using more than their apportionment. They have become reliant on it.”

Clearly, a major gap remains between the two basins about how future cuts will have to be shared. “Frankly, I don’t blame the Upper Basin,” says California’s Hasencamp. “From their perspective, the compact was intended to split the river in two with more or less equal amounts, and the promise was we’ll sign the compact so we can grow into our amount into the future. The Lower Basin was able to grow. We’ve been enjoying our full amount for many decades. It’s understandable the Upper Basin feels that it’s unfair. But life ain’t fair.”

Perhaps all the states will end up agreeing to cut their apportionments by the same percentage. Maybe the Upper Basin will get its way and the cuts will be tilted more steeply toward California and Arizona, giving the smaller states some breathing room to keep growing into their allocations — thus delaying an aggressive embrace of conservation measures that will almost surely become necessary as the river continues to decline. “Obviously, every state wants to protect its own interest,” says Utah’s Shawcroft. “But everyone knows we’ve got to solve this. No one wants to do anything but roll up their sleeves and figure out how to make it work.”

While in ordinary times, the governors’ delegates may meet once or twice a year, throughout the spring they were talking on a weekly basis. Many of the negotiators I spoke with via Zoom appeared sleep-deprived, staring vacantly at the camera and pausing regularly to rub their eyes or massage their temples. John Fleck has authored several books on the Colorado and serves as a writer-in-residence at the University of New Mexico; he says the tension between the two basins was palpable at the Stegner conference, with many Lower Basin negotiators expressing their frustration with those from the Upper Basin seeming to cast the current crisis as one that California, Arizona, and Nevada have created and are responsible for solving. From the other side, Mitchell told me she found it “almost offensive” when Lower Basin managers look to the excess allocations upriver as the only solution to the shortage. “It was a tense few days,” Fleck says. “We’ve reached a point where the buffers are gone and we can no longer avoid these hard conversations.”

In April, Secretary Trujillo ratcheted up the pressure when she sent a letter to the region’s principal negotiators that established the federal government’s priority as keeping Lake Powell above 3,490 feet of elevation, the threshold after which the Glen Canyon Dam ceases to produce power and drinking water could become impossible to deliver to the nearby town of Page, Arizona, and the LeChee Chapter of the Navajo Nation. To that end, Trujillo wrote that the Department of the Interior “requests your consideration of potentially reducing Glen Canyon Dam releases to 7.0 [million acre-feet] this year.” Making that happen would require the Lower Basin to double the cuts it has been haggling over through the 500+ Plan. If those states are unable to figure out a workable solution, the Department of the Interior has authority under the current operating guidelines to crank down the spigot of the Colorado and deliver only 7 million acre-feet anyway.

The Feds taking unilateral action to keep Glen Canyon Dam online would be completely unprecedented. But the fact that such a move no longer seems unimaginable is a mark of how precarious the situation has become. “When the pie’s shrinking, who’s going to take shortage and how much?” asks Hasencamp. “Every shortage you don’t take, someone else does. We’re all in this together, we all need to be part of the solution, and we all have to sacrifice. But we all have to be protected. We can’t have a city or agricultural area dry up and wither while others thrive. It’s one basin. Like it or not, you’re all part of L.A.”

The Multistate Battle Over the Colorado River