A Water War Is Brewing Over the Dwindling Colorado River

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This story first appeared at ProPublica. ProPublica is a Pulitzer Prize-winning investigative newsroom. Sign up for The Big Story newsletter to receive stories like this one in your inbox.

On a crisp day this fall I drove southeast from Grand Junction, Colorado, into the Uncompahgre Valley, a rich basin of row crops and hayfields. A snow line hung like a bowl cut around the upper cliffs of the Grand Mesa, while in the valley some farmers were taking their last deliveries of water, sowing winter wheat and onions. I turned south at the farm town of Delta onto Route 348, a shoulder-less two-lane road lined with irrigation ditches and dent corn still hanging crisp on their browned stalks. The road crossed the Uncompahgre River, and it was thin, nearly dry.

The Uncompahgre Valley, stretching 34 miles from Delta through the town of Montrose, is, and always has been, an arid place. Most of the water comes from the Gunnison River, a major tributary of the Colorado, which courses out of the peaks of the Elk Range through the cavernous and sun-starved depths of the Black Canyon, one rocky and inaccessible valley to the east. In 1903, the federal government backed a plan hatched by Uncompahgre farmers to breach the ridge with an enormous tunnel and then in the 1960s to build one of Colorado’s largest reservoirs above the Black Canyon called Blue Mesa. Now that tunnel feeds a neural system of water: 782 miles worth of successively smaller canals and then dirt ditches, laterals and drains that turn 83,000 Western Colorado acres into farmland. Today, the farm association in this valley is one of the largest single users of Colorado River water outside of California.

I came to this place because the Colorado River system is in a state of collapse. It is a collapse hastened by climate change but also a crisis of management. In 1922, the seven states in the river basin signed a compact splitting the Colorado equally between its upper and lower halves; later, they promised additional water to Mexico, too. Near the middle, they put Lake Powell, a reserve for the northern states, and Lake Mead, a storage node for the south. Over time, as an overheating environment has collided with overuse, the lower half — primarily Arizona and California — has taken its water as if everything were normal, straining both the logic and the legal interpretations of the compact. They have also drawn extra releases from Lake Powell, effectively borrowing straight out of whatever meager reserves the Upper Basin has managed to save there.

This much has become a matter of great, vitriolic dispute. What is undeniable is that the river flows as a much-diminished version of its historical might. When the original compact gave each half the rights to 7.5 million acre-feet of water, the river is estimated to have flowed with as much as 18 million acre-feet each year. Over the 20th century, it averaged closer to 15. Over the past two decades, the flow has dropped to a little more than 12. In recent years, it has trickled at times with as little as 8.5. All the while the Lower Basin deliveries have remained roughly the same. And those reservoirs? They are fast becoming obsolete. Now the states must finally face the consequential question of which regions will make their sacrifice first. There are few places that reveal how difficult it will be to arrive at an answer than the Western Slope of Colorado.

In Montrose, I found the manager of the Uncompahgre Valley Water Users Association, Steve Pope, in his office atop the squeaky stairs of the same Foursquare that the group had built at the turn of the last century. Pope, bald, with a trimmed white beard, sat amid stacks of plat maps and paper diagrams of the canals, surrounded by LCD screens with spreadsheets marking volumes of water and their destinations. On the wall, a historic map showed the farms, wedged between the Uncompahgre River and where it joins the Gunnison in Delta, before descending to their confluence with the Colorado in Grand Junction. “I’m sorry for the mess,” he said, plowing loose papers aside.

What Pope wanted to impress upon me most despite the enormousness of the infrastructure all around the valley was that in the Upper Basin of the Colorado River system, there are no mammoth dams that can simply be opened to meter out a steady release of water. Here, only natural precipitation and temperature dictate how much is available. Conservation isn’t a management decision, he said. It was forced upon them by the hydrological conditions of the moment. The average amount of water flowing in the system has dropped by nearly 20%. The snowpack melts and evaporates faster than it used to, and the rainfall is unpredictable. In fact, the Colorado River District, an influential water conservancy for the western part of the state, had described its negotiating position with the Lower Basin states by claiming Colorado has already conserved about 28% of its water by making do with the recent conditions brought by drought.

You get what you get, Pope tells me, and for 15 of the past 20 years, unlike the farmers in California and Arizona, the people in this valley have gotten less than what they are due. “We don’t have that luxury of just making a phone call and having water show up,” he said, not veiling his contempt for the Lower Basin states’ reliance on lakes Mead and Powell. “We’ve not been insulated from this climate change by having a big reservoir above our heads.”

He didn’t have to point further back than the previous winter. In 2021, the rain and snow fell heavily across the Rocky Mountains and the plateau of the Grand Mesa, almost as if it were normal times. Precipitation was 80% of average — not bad in the midst of an epochal drought. But little made it into the Colorado River. Instead, soils parched by the lack of rain and rising temperatures soaked up every ounce of moisture. By the time water reached the rivers around Montrose and then the gauges above Lake Powell, the flow was less than 30% of normal. The Upper Basin states used just 3.5 million acre-feet last year, less than half their legal right under the 1922 compact. The Lower Basin states took nearly their full amount, 7 million acre-feet.

PAGE, AZ – OCTOBER 16: Boats are parked at the bottom of Horseshoe Bend along the Colorado River on October 16, 2022 in Page, Arizona. The water in Lake Powell and the Colorado River has been receding due to recent droughts leaving parts of the lake and river parched. The federal government are moving forward with plans to reduce water allocations from the Colorado River Basin to Arizona and is asking millions of residents to reduce their water consumption as the drought get worse. (Photo by Joshua Lott/The Washington Post via Getty Images)

All of this matters now not just because the river, an unwieldy network of human-controlled plumbing, is approaching a threshold where it could become inoperable, but because much of the recent legal basis for the system is about to dissolve. In 2026, the Interim Guidelines the states rely on, a Drought Contingency Plan and agreements with Mexico will all expire. At the very least, this will require new agreements. It also demands a new way of thinking that matches the reality of the heating climate and the scale of human need. But before that can happen, the states will need to restore something that has become even more scarce than the water: trust.

The northern states see California and Arizona reveling in profligate use, made possible by the anachronistic rules of the compact that effectively promise them water when others have none. It’s enabled by the mechanistic controls at the Hoover Dam, which releases the same steady flow no matter how little snow falls across the Rocky Mountains. California flood-irrigates alfalfa crops destined for cattle markets in the Middle East, while Arizona takes water it does not need and pumps it underground to build up its own reserves. In 2018, an Arizona water agency admitted it was gaming the timing of its orders to avoid rations from the river (though it characterized the moves as smart use of the rules). In 2021, in a sign of the growing wariness, at least one Colorado water official alleged California was repeating the scheme. California water officials say this is a misunderstanding. Yet to this day, because California holds the most senior legal rights on the river, the state has avoided having a single gallon of reductions imposed on it.

By this spring, Lake Powell shrank to 24% of its capacity, its lowest levels since the reservoir filled in the 1960s. Cathedral-like sandstone canyons were resurrected, and sunlight reached the silt-clogged floors for the first time in generations. The Glen Canyon Dam itself towered more than 150 feet above the waterline. The water was just a few dozen feet above the last intake pipe that feeds the hydropower generators. If it dropped much lower, the system would no longer be able to produce the power it distributes across six states. After that, it would approach the point where no water at all could flow into the Grand Canyon and further downstream. All the savings that the Upper Basin states had banked there were as good as gone.

In Western Colorado, meanwhile, people have been suffering. South of the Uncompahgre Valley, the Ute Mountain Ute tribe subsists off agriculture, but over the past 12 months it has seen its water deliveries cut by 90%; the tribe laid off half of its farmworkers. McPhee Reservoir, near the town of Cortez, has teetered on failure, and other communities in Southwestern Colorado that also depend on it have been rationed to 10% of their normal water.

Across the Upper Basin, the small reservoirs that provide the region’s only buffer against bad years are also emptying out. Flaming Gorge, on the Wyoming-Utah border, is the largest, and it is 68% full. The second largest, Navajo Reservoir in New Mexico, is at 50% of its capacity. Blue Mesa Reservoir, on the Gunnison, is just 34% full. Each represents savings accounts that have been slowly pilfered to supplement Lake Powell as it declines, preserving the federal government’s ability to generate power there and obscuring the scope of the losses. Last summer, facing the latest emergency at the Glen Canyon Dam, the Department of Interior ordered huge releases from Flaming Gorge, Blue Mesa and other Upper Basin reservoirs. At Blue Mesa, the water levels dropped 8 feet in a matter of days, and boaters there were given a little more than a week to get their equipment off the water. Soon after, the reservoir’s marinas, which are vital to that part of Colorado’s summer economy, closed. They did not reopen in 2022.

As the Blue Mesa Reservoir was being emptied last fall, Steve Pope kept the Gunnison Tunnel open at its full capacity, diverting as much water as he possibly could. He says this was legal, well within his water rights and normal practice, and the state’s chief engineer agrees. Pope’s water is accounted for out of another reservoir higher in the system. But in the twin takings, it’s hard not to see the bare-knuckled competition between urgent needs. Over the past few years, as water has become scarcer and conservation more important, Uncompahgre Valley water diversions from the Gunnison River have remained steady and at times even increased. The growing season has gotten longer and the alternative sources, including the Uncompahgre River, less reliable. And Pope leans more than ever on the Gunnison to maintain his 3,500 shareholders’ supply. “Oh, we are taking it,” he told me, “and there’s still just not enough.”

On June 14, Camille Touton, the commissioner of the U.S. Bureau of Reclamation, the Department of Interior division that runs Western water infrastructure, testified before the Senate Committee on Energy and Natural Resources and delivered a stunning ultimatum: Western states had 60 days to figure out how to conserve as much as 4 million acre-feet of “additional” water from the Colorado River or the federal government would, acting unilaterally, do it for them. The West’s system of water rights, which guarantees the greatest amount of water to the settlers who arrived in the West and claimed it first, has been a sacrosanct pillar of law and states’ rights both — and so her statement came as a shock.

Would the department impose restrictions “without regard to river priority?” Mark Kelly,, the Democratic senator from Arizona, asked her.

“Yes,” Touton responded.

For Colorado, this was tantamount to a declaration of war. “The feds have no ability to restrict our state decree and privately owned ditches,” the general manager of the Colorado River District, Andy Mueller, told me. “They can’t go after that.” Mueller watches over much of the state.Pope faces different stakes. His system depends on the tunnel, a federal project, and his water rights are technically leased from the Bureau of Reclamation, too. Touton’s threat raised the possibility that she could shut the Uncompahgre Valley’s water off. Even if it was legal, the demands seemed fundamentally unfair to Pope. “The first steps need to come in the Lower Basin,” he insisted.

Each state retreated to its corners, where they remain. The 60-day deadline came and went, with no commitments toward any specific reductions in water use and no consequences. The Bureau of Reclamation has since set a new deadline: Jan. 31. Touton, who has publicly said little since her testimony to Congress, declined to be interviewed for this story. In October, California finally offered a plan to surrender roughly 9% of the water it used, albeit with expensive conditions. Some Colorado officials dismissed the gesture as a non-starter. Ever since, Colorado has become more defiant, enacting policies that seem aimed at defending the water the state already has — perhaps even its right to use more.

For one, Colorado has long had to contend with the inefficiencies that come with a “use it or lose it” culture. State water law threatens to confiscate water rights that don’t get utilized, so landowners have long maximized the water they put on their fields just to prove up their long-term standing in the system. This same reflexive instinct is now evident among policymakers and water managers across the state, as they seek to establish the baseline for where negotiated cuts might begin. Would cuts be imposed by the federal government based on Pope’s full allocation of water or on the lesser amount with which he’s been forced to make do? Would the proportion be adjusted down in a year with no snow? “We don’t have a starting point,” he told me. And so the higher the use now, the more affordable the conservation later.

Colorado and other Upper Basin states have also long hid behind the complexity of accurately accounting for their water among infinite tributaries and interconnected soils. The state’s ranchers like to say their water is recycled five times over, because water poured over fields in one place invariably seeps underground down to the next. In the Uncompahgre Valley, it can take months for the land at its tail to dry out after ditches that flood the head of the valley are turned off. The measure of what’s been consumed and what has transpired from plants or been absorbed by soils is frustratingly elusive. That, too, leaves the final number open to argument and interpretation.

All the while, the Upper Basin states are all attempting to store more water within their boundaries. Colorado has at least 10 new dams and reservoirs either being built or planned. Across the Upper Basin, an additional 15 projects are being considered, including Utah’s audacious $2.4 billion plan to run a new pipeline from Lake Powell, which would allow it to transport something closer to its full legal right to Colorado River water to its growing southern cities. Some of these projects are aimed at securing existing water and making its timing more predictable. But they are also part of the Upper Colorado River Commission’s vision to expand the Upper Basin states’ Colorado River usage to 5.4 million acre-feet a year by 2060.

It is fair to say few people in the state are trying hard to send more of their water downstream. In our conversation, Mueller would not offer any specific conservation savings Colorado might make. The state’s chief engineer and director of its Division of Water Resources, Kevin Rein, who oversees water rights, made a similar sentiment clear to the Colorado River District board last July. “There’s nothing telling me that I should encourage people to conserve,” Rein said. “It’s a public resource. It’s a property right. It’s part of our economy.”

In November, Democratic Gov. Jared Polis proposed the creation of a new state task force that would help him capture every drop of water it can before it crosses the state line. It would direct money and staff to make Colorado’s water governance more sophisticated, defensive and influential.

I called Polis’ chief water confidante, Rebecca Mitchell, who is also the director of the Colorado Water Conservation Board and the state’s representative on the Upper Colorado River Commission. If the mood was set by the idea that California was taking too much from the river, Mitchell thought that it had shifted now to a more personal grievance — they are taking from us.

Last month, Mitchell flew to California for a tour of its large irrigation districts. She stood beside a wide canal brimming with more water than ever flows through the Uncompahgre River, and the executive of the farming company beside her explained that he uses whatever he wants because he holds the highest priority rights to the water. She thought about the Ute Mountain Ute communities and the ranchers of Cortez: “It was like: ‘Wouldn’t we love to be able to count on something? Wouldn’t we love to be feel so entitled that no matter what, we get what we get?’” she told me.

What if Touton followed through, curtailing Colorado’s water? I asked. Mitchell’s voice steadied, and then she essentially leveled a threat. “We would be very responsive. I’m not saying that in a positive way,” she said. “I think everybody that’s about to go through pain wants others to feel pain also.”

Here’s the terrible truth: There is no such thing as a return to normal on the Colorado River, or to anything that resembles the volumes of water its users are accustomed to taking from it. With each degree Celsius of warming to come, modelers estimate that the river’s flow will decrease further, by an additional 9%. At current rates of global warming, the basin is likely to sustain at least an additional 18% drop in its water supplies over the next several decades, if not far more. Pain, as Mitchell puts it, is inevitable.

The thing about 4 million acre-feet of cuts is that it’s merely the amount already gone, an adjustment that should have been made 20 years ago. Colorado’s argument makes sense on paper and perhaps through the lens of fairness. But the motivation behind the decades of delay was to protect against the very argument that is unfolding now — that the reductions should be split equally, and that they may one day be imposed against the Upper Basin’s will. It was to preserve the northern states’ inalienable birthright to growth, the promise made to them 100 years ago. At some point, though, circumstances change, and a century-old promise, unfulfilled, might no longer be worth much at all. Meanwhile, the politics of holding out are colliding with climate change in a terrifying crash, because while the parties fight, the supply continues to dwindle.

Recently, Brad Udall, a leading and longtime analyst of the Colorado River and now a senior water and climate scientist at Colorado State University, teamed with colleagues to game out what they thought it would take to bring the river and the twin reservoirs of Mead and Powell into balance. Their findings, published in July in the journal Science, show that stability could be within reach but will require sacrifice.

If the Upper Basin states limited their claim to 4 million acre-feet, or 53% of their due under the original compact, and the Lower Basin states and Mexico increased their maximum emergency cuts by an additional 45%, the two big reservoirs will stay at roughly their current levels for the next several decades. If the basins could commit to massive reductions below even 2021 levels for the Upper Basin and to more than doubling the most ambitious conservation goals for the south, the reservoirs could once again begin to grow, providing the emergency buffer and the promise of economic stability for 40 million Americans that was originally intended. Still, by 2060, they would only be approximately 45% full.

COLORADO RIVER DELTA, BAJA CALIFORNIA – OCTOBER 24: Drought, overconsumption, and climate change, are main factors dissipating the amount of Colorado River water that will reach the Sea of Cortez on its journey through the Colorado River Delta on October 24, 2022 in Baja California, Mexico. The flight for aerial photography was provided by LightHawk. (Photo by RJ Sangosti/MediaNews Group/The Denver Post via Getty Images)

Any of the scenarios involve cuts that would slice to the bone. Plus, there’s still the enormous challenge of how to incorporate Native tribes, which also hold huge water rights but continue to be largely left out of negotiations. What to do next? Israel provides one compelling example. After decades of fighting over the meager trickles of the Jordan River and the oversubscription of a pipeline from the Sea of Galilee, Israel went back to the drawing board on its irrigated crops. It made drip irrigation standard, built desalination plants to supply water for its industry and cities, and reused that water again and again; today, 86% of the country’s municipal wastewater is recycled, and Israel and its farmers have an adequate supply. That would cost a lot across the scale and reach of a region like the Western United States. But to save the infrastructure and culture that produces 80% of this country’s winter vegetables and is a hub of the nation’s food system for 333 million people? It might be worth it.

A different course was charted by Australia, which recoiled against a devastating millennium drought that ended 13 years ago. It jettisoned its coveted system of water rights, breaking free of history and prior appropriation similar to the system of first-come-first-served the American West relies on. That left it with a large pool of free water and political room to invent a new method of allocating it that better matched the needs in a modern, more populous and more urban Australia and better matched the reality of the environment.

In America, too, prior appropriation, as legally and culturally revered as it is, may have become more cumbersome and obstructive than it needs to be. Western water rights, according to Newsha Ajami, a leading expert at Lawrence Berkeley National Laboratory and the former director of the urban water policy program at Stanford University, were set up by people measuring with sticks and buckets, long before anyone had ever even considered climate change. Today, they largely serve powerful legacy interests and, because they must be used to be maintained, tend to dissuade conservation. “It’s kind of very archaic,” she said. “The water rights system would be the first thing I would just dismantle or revisit in a very different way.”

This is probably not going to happen, Ajami said. “It could be seen as political suicide.” But that doesn’t make it the wrong solution. In fact, what’s best for the Colorado, for the Western United States, for the whole country might be a combination of what Israel and Australia mapped out. Deploy the full extent of the technology that is available to eliminate waste and maximize efficiency. Prioritize which crops and uses are “beneficial” in a way that attaches the true value of the resource to the societal benefit produced from using it. Grow California and Arizona’s crops in the wintertime but not in the summer heat. And rewrite the system of water allocation as equitably as possible so that it ensures the modern population of the West has the resources it needs while the nation’s growers produce what they can.

What would that look like in Colorado? It might turn the system upside down. Lawsuits could fly. The biggest, wealthiest ranches with the oldest water rights stand to lose a lot. The Lower and Upper Basin states, though, could all divide the water in the river proportionately, each taking a percentage of what flowed. The users would, if not benefit, at least equally and predictably share the misery. Pope’s irrigation district and the smallholder farmers who depend on it would likely get something closer to what they need and, combined with new irrigation equipment subsidized by the government, could produce what they want. It wouldn’t be pretty. But something there would survive.

The alternative is worse. The water goes away or gets bought up or both. The land of Western Colorado dries up, and the economies around it shrivel. Montrose, with little left to offer, boards up its windows, consolidates its schools as people move away, and the few who remain have less. Until one day, there is nothing left at all.

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