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Residential swimming pools use groundwater in the Sonoran Desert in Buckeye, Arizona.Kyle Paoletta/October 30, 2023Running DryThe Water Wars Deciding the Future of the WestFrom conservation to importing water from the Pacific, Democrats say they have all the answers to historic drought. The one thing no one wants to talk about: stopping the sprawl.Photographs by Rebecca Noble for The New Republic

Residential swimming pools use groundwater in the Sonoran Desert in Buckeye, Arizona.

On the eastern flank of metropolitan Las Vegas, out past a water park advertising “the world’s largest man-made wave” and a nascent development called Cadence, a red-dirt parking lot teases public access to the system that enabled the past three decades of growth in southern Nevada. Called the Las Vegas Wash, it amounts to a channel that funnels the area’s recycled water back to its aquatic lifeline: Lake Mead.

Bushwhacking through the cottonwoods that line the wash and past a massive desert tobacco plant’s spray of flutelike flowers reveals the riverbank. Whatever sense of the pastoral I was enjoying in the bright December sun was immediately disrupted by the water itself, which gave off a distinctive odor—not definitively chemical, but certainly treated. Overhead, three pelicans with black-tipped wings swooped into view, wheeling into an updraft while, in the elbow of one of the concrete weirs that control the wash’s 12-mile run through the Las Vegas Valley, a few cans of Monster energy drink bobbled in the foam.

Every day, 200 million gallons of water are returned to Lake Mead—the nation’s largest reservoir—through the wash, enough to virtually replace all of the water that’s used indoors by the 2.3 million residents of Clark County. The ultimate source is the Colorado River and the contentious ledger that governs the waterway’s use throughout its 1,450-mile run between the Rocky Mountains and the Sea of Cortez, which separates Baja California from the rest of Mexico. While Las Vegas is now widely recognized as a national leader in water efficiency, the situation was completely different in the late 1980s, when the city was gulping down its meager allocation of the Colorado so quickly that some believed the burgeoning metropolis would go completely dry by 1995. Early in her two-decade tenure as Las Vegas’ top water official, Patricia Mulroy, who has lingered in the regional imagination as a sort of water wizard, was forced to call a moratorium on new development. Back then, Las Vegas was less than a third the size it is today.

A few weeks after my visit to the Las Vegas Wash, Katie Hobbs, the newly elected governor of Arizona, released a report showing that the rapidly expanding far West Valley of Phoenix was pumping groundwater at an unsustainable rate. “We have to act now, or this will only be the first new area that faces this kind of shortage,” the Democrat said in her debut address upon taking office. She followed up that promise in June by issuing her own moratorium on any new development in metropolitan Phoenix that is entirely reliant on groundwater. Regulators had found that many of the outlying communities in Maricopa County were out of compliance with a state law requiring all new residential construction to have a guaranteed supply for 100 years.

Hobbs prevailed over the far-right former news anchor Kari Lake by just 17,000 votes last year, in a contest that seemed to demonstrate the electoral limits of the Republican Party’s total embrace of MAGA-style extremism. The only gubernatorial race with a narrower raw vote margin in 2022 was in Nevada, where the more establishment-oriented—if not exactly moderate—Republican Joe Lombardo squeaked ahead of the incumbent, Steve Sisolak, by a mere 15,000 votes. Those races were indicative of the Southwest’s drift from the sort of place that birthed Republican icons like Barry Goldwater, Paul Laxalt, and John McCain into one of the most competitive regions in the country. While Hillary Clinton’s narrow 2016 loss there hinted at what was coming, Arizona, especially, seemed to flip from ruby red to periwinkle blue almost overnight, with Republicans managing to lose both U.S. Senate seats, the governorship, and the state’s Electoral College votes in just four years.

Democrats across the country hope the Southwest’s largest state will be the next Colorado: a longtime libertarian stronghold reborn as progressive haven thanks to rapidly growing Democratic cities and moderate suburbs. Meanwhile, Arizona’s conservatives have seized on water restrictions as fuel for the fire of cultural grievance they have traditionally used to seek power. When I spoke to him this summer, far-right Representative Paul Gosar called Hobbs’s development moratorium “an impulsive scare tactic.” “It’s not your way or the highway,” said Gosar, who is a close ally of Lake, traveling with her to a Conservative Political Action Conference (CPAC) event in Hungary earlier this year. “It scared people, it really did,” he said, adding, “We have plenty of fresh water. It’s just the distribution that’s the problem.”

Distribution is certainly part of the problem. Over the course of the twentieth century, tens of billions of federal dollars were used to move water across the vast Colorado River Basin, which encompasses Southern California, Arizona, Nevada, Utah, New Mexico, Wyoming, and Colorado itself. The transformation of the basin began in the 1930s with the construction of the Hoover Dam, which created Lake Mead, and ended in 1993 with the completion of the Central Arizona Project, the 336-mile aqueduct system that conveys water from the Colorado to Phoenix and Tucson. All that infrastructure has made it possible for the river system to theoretically supply water to more than 40 million people and five million acres of farmland. But the basin’s stability depends less on dams and reservoirs than on rainfall and snowpack, and it has been shaken by a so-called megadrought that set in just over two decades ago. Climate scientists now believe the dry conditions are reflective of a trend toward more permanent aridification. Their research also shows that water scarcity is only made worse by the region’s triple-digit summers—especially brutal this year—given the link between high temperatures and groundwater depletion. (Gosar has falsely claimed that “the science is not settled” on climate change and suggested plants will take care of all the excess CO2 in the atmosphere through the magic of photosynthesis.)

Over the past 20 years, public officials in the Southwest responded to aridification by shifting their emphasis from corralling and diverting water to making better use of what’s already available, allowing the region’s cities to explode in size merely by reducing their per capita water use. But with aquifers already overtaxed across the Southwest, the region is also coping with the first-ever limitations on how much water can be diverted from the Colorado, which went into effect after Lake Mead dropped below 35 percent full in 2021. Arizona has borne the brunt of the cuts: This year, its allocation of Colorado River water was cut by 592,000 acre-feet, with each acre-foot representing enough water to supply around three households annually. Though above-average snowfall in the winter of 2022–23 helped to temporarily stabilize the reservoir, its water level has only recovered to around the same elevation as when mandatory cuts first went into effect. Next year, Arizona will still have to make do with only 82 percent of its typical allocation.

In response to the sense of crisis that has descended over the Southwest, momentum is building for a return to the era of massive federal investment in waterworks. Already, the region’s congressional delegation succeeded in securing $4 billion in the Inflation Reduction Act for drought mitigation, as well as over $10 billion in the Bipartisan Infrastructure Law for the Bureau of Reclamation, the agency that manages the West’s dams and aqueducts. The next logical step would be augmenting the region’s water supply, namely by importing water from elsewhere. Of all the region’s legislators, Senator Mark Kelly of Arizona seems most ready to go back to the future by betting big on new infrastructure. “We need to start looking long-term: What do we want the Southwest to look like 15, 20, 30 years from now?” he asked me this summer. “The Bureau of Reclamation has done a bunch of studies about moving water from another watershed [as well as] desalination. These things are possible to do, but we’ve got to plan ahead and start having those conversations.”

Kelly’s public embrace of augmentation comes after Hobbs’s predecessor, Doug Ducey, sought $1 billion for a proposed desalination plant in the Sea of Cortez, which would ferry water to Phoenix via a 200-mile pipeline. When the Republican-led legislature approved that plan, a poll found that 74 percent of likely voters in Arizona were in support of purging the salt from ocean water to propel them into the future. When respondents were informed the full build-out could cost upward of $10 billion, support only barely softened, to 63 percent. Whatever the cost, this sort of augmentation project is viewed by many as practical, even inevitable. John Graham, one of Arizona’s most prominent real estate developers, typically donates to Republicans but endorsed Hobbs in 2022 because he feared the “toxic” environment that Kari Lake might have created. When I asked him about investing in augmentation infrastructure, he replied simply, “We have to.”

Not everyone in the Southwest is quite so certain. Beyond the environmental toll desalination plants take on the bodies of water where they’re located and the immense amount of energy pumping water over long distances requires, critics charge that augmentation’s only real purpose would be to facilitate the local tradition of shortsighted sprawl. “The Southwest, for a long time, has been based on economic growth, which is getting as many people here as possible, as many microchip factories, as many golf courses,” Brian Petersen, an environmental scholar at Northern Arizona University, told me.

Petersen pointed out that, some years after first mapping the Colorado River in 1869, the nineteenth-century explorer John Wesley Powell gave a speech in which he told an audience of aspiring farmers and land speculators, “There is not enough water to supply the land.” After well over a century of ignoring that warning, the Southwest seems poised to keep forging ahead, clawing at whatever new water resources it can in desperate hopes of further staving off the inevitable moment when its people are forced to accept the inherent limitations of the desert. Even as Democrats lead the national charge toward tackling climate change, they are continuing to preach at the altar of growth. That may solidify their electoral gains in the Southwest, but it also risks a different sort of environmental chaos.

For many residents of Cochise County, in the far southeastern corner of Arizona, the first sign of trouble was the dust. Starting around 2019, the wind that gusts through the Sulphur Springs Valley would pick up loose grit from the thousands of acres of arid land that were being cleared to grow alfalfa. So much dirt became airborne that even the Chiricahua Mountains, towering 6,000 feet above the sunbaked valley, would sometimes disappear. “The dust was so dark, thick, and high that you could not see the mountains,” remembered Beau Hodai, a journalist who lives in the valley. “I looked up a number of times and thought the town was on fire because there were just huge plumes of black smoke rising.”

The company clearing all that land was Riverview Dairy, which first arrived in Cochise County in 2014, two years after local officials made it easier to obtain agricultural permits there. It was an appealing spot for the Minnesota-based producer: The aquifer could be pumped easily because of its low salt content, and the mild winters meant it was possible to grow alfalfa year-round. But as Riverview sank 60 wells to water the 20,000 acres it had amassed, the water table dropped, endangering small farmers who couldn’t afford to extend their wells deeper into the ground. An activist group called Arizona Water Defenders formed in response, gradually coalescing around a plan to pass a ballot referendum that would establish a regulatory apparatus known as an Active Management Area, or AMA, over groundwater in the Sulphur Springs Valley. Under that designation, all current use would continue under the supervision of the Arizona Department of Water Resources, but the sinking of new wells would be significantly curtailed.

Over the course of the campaign for the new regulation, water management—the once staid domain of utilities and engineers—transformed into yet another front in Arizona’s culture war. Two months before the referendum, the Water Defenders invited Kristine Uhlman, a retired hydrologist from the University of Arizona, to give a presentation at the YMCA in the border town of Douglas. Uhlman focused on the simple idea that, in the Sonoran Desert, groundwater is not a renewable resource. “All of these aquifers are savings accounts, meaning water went in, and it’s been sitting there for thousands of years,” she recalled explaining. “In one location south of Phoenix, we have water that’s 23,000 years old. In Cochise County, it’s 10,000 years old. You are relying on a savings account. So how do you manage the water you use, knowing that once you use it up, it’s gone?”

“We assiduously avoided any whiff of partisanship,” added MaryAnn Capehart, one of the event’s organizers. “Really carefully, at all times. We did not want to be identified with a party. We even avoided using the word ‘environmental’; apparently that triggers people.” Those efforts to steer clear of partisanship were vital in a county where Donald Trump crushed Joe Biden by 20 points. Still, Capehart was struck by the libertarian fatalism with which some members of the Douglas audience greeted Uhlman’s presentation. “I’ve got a well; when it dries up, it dries up. I’ll just move to town,” Capehart remembered one attendee saying; another: “My water’s going to go down, who cares? We just don’t want government in here.”

Ann Waters, a leather worker who lives in McNeal, rejects the very idea that the region’s groundwater is endangered. “They’re lying about the aquifer drying up,” she told me. “My neighbors down the road, their water level has risen…. All these people who said their wells went dry, they just had to replace an ancient pump.” To her mind, the campaign for new regulation amounted to “a communist takeover. It’s against the Fifth Amendment to seize private property, and that’s what the AMA does.”

Elsewhere in rural Arizona, the priority system that governs the use of Colorado River water has meant that the cuts to how much water the state can divert through the Central Arizona Project—which went into effect last year—have fallen almost entirely on farmers in Pinal County, which sits between Phoenix and Tucson. As a result, those farmers have been pumping groundwater to make up the difference, even as the state is projecting an eight million-acre-foot shortfall in the amount of groundwater available to residential users in Pinal over the next century. Patrick Bray, an executive at the Arizona Farm and Ranch Group, sees the situations in Cochise and Pinal as evidence of the profound strain the current regulatory regime—modest though it may be—is taking on rural areas. “The course of action is, OK, how can we regulate a user, how can we shut somebody down, how can we cap their wells, meter them—what regulatory rules can we throw at this thing to quote unquote save water,” he said. “We need to be focused on a grander future. How are we going to continue to be sustainable? How are we going to get those new sources of water?”