Apr 17, 2024

The Colorado River waters our crops. What if it dries up?

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Part of the issue The 100-year-old mistake that’s reshaping the American West from The Highlight, Vox’s home for ambitious stories that explain our world.

An hour east of San Diego, there’s a lonely stretch of dry, barren land. There’s not much here but sand, dirt, and some wiry shrubs.

But keep driving east and the landscape suddenly shifts.

Near El Centro, a small city just north of the Mexican border, browns and washed-out reds erupt into emerald greens. A patchwork of verdant farmland stretches to the horizon.

Here, in the Imperial Valley of California, humans have transformed the desert into an agricultural oasis. What was once parched ground is now rows of lettuce, carrots, and cabbage, or fields of alfalfa.

Rain almost never falls here. What makes this region so lush is the Colorado River, a water source that lies another 60 miles east along the Arizona border.

While it may seem odd to grow all of this food in the desert, American consumers benefit from it. The region — which includes the Imperial Valley, Coachella Valley, and Yuma, Arizona, encompassing hundreds of thousands of acres of farmland — grows as much as 90 percent of all leafy vegetables consumed in the US between November and March. Chances are, the main ingredients of any salad or vegetable soup you’ve had during winter came from here. And they were likely grown with water from the Colorado River.

But a big problem looms: The river is vanishing.

More than two decades of a severe drought, coupled with a long history of mismanagement, has cut the river’s flow by roughly 20 percent since the 1900s. The Colorado’s largest reservoir, Lake Mead, is less than a third full. While the heavy rains and snow this past winter could help buffer the ongoing crisis, they won’t change the reality that the river is simply running out of water.

This could create trouble for farmers in the desert Southwest. They’ll likely have less water in the years to come, especially as climate change dries out the West. That could, in turn, shrink the supply of winter veggies nationwide, making them more expensive for consumers. The ongoing drought could also harm the region’s economy and its many farming families, some of whom have been growing food here for more than a century.

I had these consequences in mind when I traveled to California and Arizona last month. My goal was to understand just how severe the river crisis really is and how to cope with it.

After talking with nearly 20 farmers, economists, and water experts, what I found was something of a mess. The policies that govern the river are incredibly complicated and inflexible, and they have failed to adapt to the grim realities of climate change. The only real option, as far as I can tell, is for the river’s many beneficiaries — including farmers in the Imperial Valley and Yuma — to use less, and using less is painful.

The water that feeds our winter produce starts out as rain, snow, and glacial melt in the Rocky Mountains of Colorado. Flowing from a lake atop the continental divide, the river rushes south for more than 1,000 miles, passing through the Grand Canyon and past Las Vegas before running into the Imperial Dam.

The Imperial Dam, which is just north of Yuma, diverts part of the river into a large channel called the All American Canal. That’s what turns the desert near El Centro green: The canal carries water roughly 80 miles west to farms in the Imperial Valley, at one point cutting straight through a field of dunes. The water here seems eerily out of place.

More than 100 years ago, the US government encouraged Americans to populate rural areas like this, build infrastructure, and farm more land, according to Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University. That’s when engineers started building canals to take water from the Colorado River. At the time, the US policy was “to try to get every acre of land under the plow,” Porter said.

These canals turned the desert into a produce powerhouse. When farmland in Iowa or Nebraska is frozen and blanketed in a thick layer of snow, it’s 70 degrees and sunny in the Imperial Valley and Yuma. As soon as there was enough water in the mix, the conditions were ideal for growing crops year-round.

Today, the Imperial Valley, Coachella Valley, and Yuma together use close to 4 million acre-feet of water per year. That’s an enormous amount, equal to roughly a third of the entire flow of the river. (An acre-foot fills one acre of land with one foot of water and is roughly what two average houses use each year.)

That water appears everywhere when you wander around the region. It fills small concrete channels that border farms and sprays from sprinklers that line fields of romaine. In Yuma, I saw a date farm flooded with so much water that it created a shallow pool. Here, the threat of drought feels distant, yet all that water comes from the same, dwindling resource.

The crisis along the Colorado River is a mess of our own making, and it’s rooted in a decision made more than 100 years ago.

In 1922, a landmark agreement called the Colorado River Compact divided the river among two groups of states: the upper basin and the lower basin. The upper basin includes Utah, Wyoming, Colorado, and New Mexico, and the lower basin comprises California, Nevada, and Arizona.

In determining the share each basin would get, water officials ignored inconvenient science and massively overestimated the river’s average flow. Western water users each got a piece of the river, but — together with water later allocated to Mexico through a treaty — those pieces turned out to be more than what it can offer in a typical year. (The 1922 decision also failed to spell out what shares would be given to the 30 or so tribal nations in the basin.)

Meanwhile, water officials didn’t factor in the possibility of a changing climate. Decades of recent warming have been drying out the West, causing less water to flow into the river. Scientists estimate that every degree Fahrenheit of warming reduces the river’s flow by about 4 percent. That’s concerning because they expect temperatures in the basin to rise as much as 5 degrees F by the middle of this century, relative to the 1900s.

Together, these two problems have drained the river. Last summer, Lake Mead and Lake Powell — which provide not only water to millions of people, but also an enormous amount of electricity — fell to historic lows and drew dangerously close to “dead pool.” That’s when water is so low in the reservoirs that it can’t pass downstream through the dams, and beyond the level when it can no longer spin turbines to generate hydropower.

“We’re at a danger point,” John Fleck, an author and Colorado River expert, told me last fall. The reservoirs can store roughly four times the river’s annual flow, providing water and power during a drought. But Western states have burned through nearly all of that storage in just 20 years, Fleck said.

The recent flooding in California and snowfall in the Rockies could raise the reservoirs, though probably not by much. The ground is still so dry in much of the West that it absorbs a lot of the runoff before it even reaches the river. “We’re far from filling the reservoirs in the Colorado River system,” Paul Miller, a hydrologist at the Colorado Basin River Forecast Center, said in a press conference last month.

What this means for farmers and the food they grow is complicated.

The Law of the River, which dates back to the 1922 allotment, details which regions have to give up water in times of scarcity and which ones can keep their taps turned on. Typically, the people who have the most senior, protected rights to the river are those who have been using water for the longest, and use it toward something that the government deems “beneficial.”

Those people include farmers in the Imperial Valley, Coachella Valley, and Yuma, who grow our winter veggies; they have incredibly senior rights. Growers have been farming land here for decades using water from the Colorado River — in some cases, since before the Bureau of Reclamation was established in 1902.

“We are blessed with a huge allocation because pioneers saw the potential here,” said Craig Elmore, a third-generation vegetable farmer in the Imperial Valley. His grandfather came here in 1908 to help build some of the region’s original canals. “We were using water before any dam or federal intervention.”

(Indigenous people and their ancestors have lived in the region for thousands of years. They, too, are legally entitled to a large portion of the river’s water but — for a number of reasons — have a hard time realizing those rights.)

Those senior water rights have, so far, protected farmers in California and Yuma. While the drought-fueled drop in Lake Mead has already triggered mandatory cuts under the Law of the River, they’ve only hit cities and farms in Nevada, other parts of Arizona, and Mexico; regions with more junior rights. Earlier this year, farmers in Pinal County, Arizona, for example, lost access to their river water, while those in California and Yuma were spared. That’s why these growers are water-rich when other regions are cutting back.

Yet even senior rights can’t protect farmers from cutbacks if the river is running out of water.

Over the summer, the Bureau of Reclamation, the government agency that manages water in the US, announced that the lower basin states will have to cut an additional 2 million to 4 million acre-feet — at least in the short term — to prevent the system from crashing. That’s as much as one-third of the river’s annual flow, enough to flood the entire city of Phoenix with more than 6 feet of water.

Many farmers in the Imperial Valley, Coachella Valley, and Yuma will have to contribute to reach a cutback on that scale. The simple fact is that agriculture in this region uses so much of the river’s water — more than Los Angeles, Phoenix, and Las Vegas combined — that it’s hard to imagine a large reduction without them.

“We’ve always relied on our water rights,” said Tina Shields, the water department manager at the Imperial Irrigation District (IID), a public agency that provides water and power in the Imperial Valley. “But if there’s no water in the system, that’s a different story.”

The best-case scenario, Shields said, is that growers will be paid through government funds to reduce their water consumption, and it would be entirely voluntary. Some of those funds could come from the Inflation Reduction Act or the Bipartisan Infrastructure Law, which together set aside more than $15 billion for the Western drought. This concept isn’t new: IID already runs a program that pays farmers if they can demonstrate that they’re saving water. The city of San Diego funds the program, essentially paying IID for the water that those farmers conserve.

Conserving water obviously sounds like a great idea. The problem is that farmers in these regions are already highly efficient. Water-saving technologies are also pricey, and farmers I spoke to are concerned that any future payments won’t be enough to cover them.

“I’m not sure how much less water I can use,” Jack Vessey, a fourth-generation farmer in the Imperial Valley, said one cloudy morning as we drove by his fields of cabbage. Sprinklers coated the turquoise plants with beads of water.

Vessey uses sprinklers to water his cabbage and other leafy greens, he said, instead of just flooding water down rows in the field (which is a cheaper, more traditional technique known as flood irrigation). Each year, sprinklers save him as much as 1.5 acre-feet of water per acre, he said.

Many farmers here also use drip irrigation, another water-saving technique, and commonly level their fields with lasers. By making the soil perfectly flat, precise leveling ensures that more water sinks into the ground instead of running off the farm.

Because farmers are already so economical with their water, any new restrictions — which could cut their water usage by 10 percent or more, experts told me — would likely force them to grow less. They may have to harvest crops fewer times each year, for example, or leave some of their fields bare for a season or more.

“That’s fallowing, which we don’t like down here,” Shields told me when I met her at IID’s headquarters, several modest buildings in the town of Imperial, just north of El Centro. “We call it the ‘F-word’ because it has so many impacts on our community.”

Some growers told me that they might plant fewer acres of alfalfa and other kinds of hay, since these “secondary” crops tend to be less lucrative than veggies. “Secondary crops will probably go by the wayside,” said Elmore, who’s also a director at the Imperial Valley Vegetable Growers Association, an industry group. “A lot of ground that’s being farmed right now will probably become unproductive.”

Other farmers said they might grow fewer water-intensive vegetables, such as onions, or cut back on produce altogether. Celeste Alonzo, a third-generation grower in the Coachella Valley, said her family will probably downsize to adapt to less water and stop growing bell peppers, for example.

Estimating exactly how farmland here will change isn’t easy; acreage depends not just on water, but on the value of different crops. Overall, however, farmland is almost certainly going to shrink in the coming years, said Kurt Schwabe, an economist who studies water and agriculture at the University of California Riverside. It’s just a question of by how much.

“Business as usual won’t be business as usual in the future,” he told me.

Should farmers grow less food, consumers could feel the pain. Although there are plenty of regions that grow forage crops that fuel the meat and dairy industry — helping buffer any regional shortfall in supply — the Imperial Valley, Coachella Valley, and Yuma grow nearly all of the country’s vegetables for more than five months out of the year.

“The biggest risk that we’re going to have is the possible reduction in the supply of veggies,” said Mike Pasquinelli, a third-generation grower in Yuma who buys and markets produce.

That could increase retail prices, he said, and some experts agree.

Vessey, the fourth-generation farmer and another director of the Imperial Valley Vegetable Growers Association, put it bluntly: “Where are you going to have a Caesar salad in February? If the Colorado River isn’t growing produce, good luck. The American consumer is going to pay more for food.”

But there are also other troubling consequences should farmers cut back.

One sunny morning in March, I stood in a field of romaine in Yuma. There were rows and rows of lettuce, each with bright green leaves organized like loose petals of a flower. A dozen or so men, wearing baseball caps and rubber boots, harvested the field in front of me and spoke among themselves in Spanish.

Workers like these — many of whom come over from Mexico for the day’s work — could lose a source of income if farmland here shrinks. Growers told me repeatedly that agriculture is the engine that runs the economy in Yuma and the Imperial Valley. “If we don’t farm, our community suffers,” said Pasquinelli, who sells the lettuce these men were harvesting.

A shortage of water on farmland could also threaten wildlife. The Salton Sea, California’s largest lake by surface area, is home to a wide range of birds, and it’s fed by wastewater that pours off farmland in the Imperial and Coachella Valleys. Without farming, the sea would eventually evaporate.

It has been evaporating already. The shallow lake is receding as farmers become more water-efficient, exposing vast areas of beach — which emit toxic dust linked to asthma — and making the water salty. Extreme salinity appears to have killed much of the lake’s fish and invertebrate populations, causing declines in fish-eating birds.

“You just don’t see what you used to,“ said Robert McKernan, a retired ornithologist who’s been studying the Salton Sea since the 1970s. Populations of American white pelicans and Caspian terns, for example, seem to have shrunk in recent years.

If farmers become more efficient with water, it could accelerate the sea’s decline, another example of how even solutions to the river crisis come with consequences.

There is some relief in sight: The state and federal governments have promised hundreds of millions of dollars to control the toxic dust and create wetlands for wildlife. Yet those efforts are unlikely to be sufficient to fix the problem, experts told me.

It’s ironic that water being diverted to grow food is helping to sustain this area’s wildlife, considering that farming is one of the largest drivers of biodiversity loss worldwide. Here, McKernan said, many birds “need agriculture.”

This summer, Reclamation will announce how it intends to slash the amount of river water supplied to cities and farms in the Southwest. There are two main options on the table: honor the existing rights-based system, forcing urban regions of Arizona and Nevada to suffer deep reductions; or spread the pain evenly among the river’s users, regardless of their seniority. The second option could expose Imperial Valley and Yuma farmers to severe cuts.

In a March statement to Vox, the Interior Department (which oversees Reclamation) said it’s pursuing a “consensus-based approach” to find ways to save water in the basin, while “preparing to use its authorities” to protect the river. Tyler Cherry, a spokesperson for the department, declined to specify how it would use those authorities. But if the seven states that depend on the river can’t reach an agreement on their own, it’s clear that the department could try to impose mandatory cuts that sidestep the existing Law of the River.

“The prolonged drought afflicting the American West is one of the most significant challenges facing our country today,” Tommy Beaudreau, deputy secretary of the interior, said earlier this month at a press conference in a room overlooking Lake Mead and the Hoover Dam. “We cannot kick the can on finding solutions.”

Ultimately, Reclamation is very likely to honor the existing priority system, according to Michael Cohen, a senior researcher at the Pacific Institute, a nonprofit water policy organization. Still, it may be hard for states to reach a major reduction without forcing the hands of farmers. “A 2 to 4 million acre-feet reduction is a big lift,” Shields, of the Imperial Irrigation District, said. “Let’s be honest: You can’t do that voluntarily. You need a regulator to come in and tell you how it’s going and give you someone to blame.”

The farmers I spoke to strongly oppose spreading cuts evenly among the river’s users. Beyond having senior rights, they’ve already cut consumption in order to provide water to urban areas, they said.

“Why should my business sacrifice to the point of probably going out of business so another industry in a junior area can continue to flourish?” said Elmore, whose family has been involved in water fights for decades. “We cannot sacrifice. I have dozens of families that are dependent on my farm staying in business.”

But for many growers, the writing is on the wall: More restrictions are inevitable. Western cities have more people and larger economies, and they, too, have already cut their water usage significantly. Ultimately, if it’s between drinking water for Phoenix and Vegas and irrigation for fields of alfalfa, it’s pretty clear that these urban areas will take priority.

“I love farming, and I see how important it is,” Porter of Arizona State University said. “But the pressures for moving that water supply for urban use — or leaving that water in the system for other uses — are just going to be overwhelming.”

On my last day in the region, I sat on the bank of the Colorado River near the border of California, Arizona, and Mexico. Here, downstream from most of the dams and the canals, the river was narrow. It was more like a stream. A group of waterbirds paddled near the shore, each occasionally disappearing under the current. It was strange to imagine that this is the water that everyone is fighting over.

I’ve spent the last few weeks searching for a good solution to the crisis, an end to this story. No source I found could offer one. Any effort to restore the river will mean some people (or animals) get less water, barring several more winters like this one. And there’s no way around that, no secret technology to grow food without water. “It’s just such a complicated, ugly problem,” Schwabe said.

It’s an unsatisfying conclusion. Then again, maybe that’s what climate change creates: ugly problems where everybody loses. The best thing we can do, perhaps, is to sober up to this reality — that climate change will reshape economies and human lives — and use that knowledge to prepare.

Scientists have known for decades that the Colorado River is over-allocated and that warming is drying out the basin. Yet water regulators have failed to act in a meaningful way to rebuild Lake Powell and Lake Mead, Schwabe said. They should have started overhauling the Law of the River years ago, he said, instead of always being in “crisis mode.”

“The longer you wait to act, the more drastic your action has to be,” Schwabe said. “If we had started making these cutbacks in the ’80s and ’90s, in incremental steps, we probably wouldn’t be talking about this today. The situation is dire because we failed to act previously.”

Correction, April 18, 2:45 pm ET: An earlier version of this story misstated how the 1922 agreement to apportion the Colorado River was decided. Western states, and not a federal agency, negotiated the division of water.

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