What Happens to the Grand Canyon if the Colorado River Dries Up?

This article originally appeared on Outside

I'm one of those people who will tell you that a river trip in the Grand Canyon changed her life. Last May, after joining a friend's 50th birthday celebration on a guided rafting trip on the upper portion of the canyon, I paddled, mesmerized by the spectacular shades of red and orange rock walls towering above me, their layers telling stories of geology, history, and the innermost workings of the Sonoran Desert. I'm sure our guides told us about all of it, but it wasn't the details that moved me. It was the river itself, the transformative power of being ferried by the wondrous lifeforce from our put-in to our take-out. I can't say exactly how, but when I emerged from the canyon after six days of floating and sleeping alongside those flowing waters, I was different. I was better.

Now, I wonder how many more people after me will get to experience the same magic. Climate change, a rising population, and unsustainable consumption of water in the southwest are threatening the very existence of the Colorado River that's been running through the center of the Grand Canyon for six million years. It's a complex issue that seven states and Mexico--all of which utilize water from the river--have been fighting about for years. And it's a dilemma the Biden-Harris administration recently dedicated $15.4 billion dollars towards trying to solve, including a deal, announced on May 22, to give $1.2 billion dollars to the states of Arizona, California, Nevada, and several Native American tribes in exchange for cutting their water consumption between now and the end of 2026.

The situation runs much deeper than keeping the water flowing so people like you and me can hoot, holler, and regenerate on rafting trips. But if floating the Colorado River through the belly of the Grand Canyon is on your bucket list, it's time to put your plan into action. Wait too long, and there may not be a river to run. Or, at least, regulations on boating trip sizes may make securing a permit or a spot on a guided trip harder than they are now. It could even make running the river more dangerous.

If rafting isn't possible in the future, there's no guarantee that another form of recreation--one that allows us to marvel at the canyon’s magnitude from the base of the canyon--will take its place. So before you start imagining being able to walk, hike, run, or even ride a bike down the center of the Grand Canyon, think about this: with the Colorado River drying up, the entire ecosystem will change. The animals who drink from the river, and eat the plants that grow from the river, will leave. Plant life will transform--more cactus than trees--and inhospitable heat will make recreation of any sort unbearable. And though adventurous pursuits may seem like a shallow concern next to water rights, agriculture, and livelihoods, most conservationists started as recreationalists. Right now, 27,000 people travel downriver through the Grand Canyon each year, and hopefully each one leaves caring more about preservation--good news for Earth, who needs all the help she can get.

The Colorado River Is Drying Up: How This Impacts the Grand Canyon's Future

The Colorado River runs roughly 1,450 miles in its entirety, originating in Colorado's Rocky Mountain National Park and gaining momentum from snowmelt and tributaries as it winds south towards Mexico. It used to reach the coast, but has trickled to a dry, dusty wash miles inland since 1980.

According to Brian Buma, a climate scientist who works for the Environmental Defense Fund (EDF) in Boulder, Colorado, every one degree Celsius of air temperature rise due to climate change-induced warming leads to a 6.5 percent reduction (plus or minus roughly 3.5 percent) in the Colorado River's base flow.

"As the temperature goes up, we simply evaporate more water at every step of the process," says Buma. Despite the great snowfall the region received this past winter, Buma says that by 2070, there will be a 20-30 percent decrease in snowpack around the Upper Colorado River basin, also due to climate change. "Drought conditions and a warmer earth mean water that might join a tributary that flows into the Colorado River evaporates (either directly or via plants) back into the atmosphere instead."

Explosive population growth in the southwest also plays a role. The Colorado River Compact--which allocates water rights between the Upper (Colorado, New Mexico, Utah, Wyoming) and Lower Basins (Arizona, Nevada, California) was created and signed in 1922 when there were roughly 500,000 people across those seven states. "The assumption was that the population of the Southwest would never be more than four times the amount of that population," says Sinjin Eberle, Southwest Region Communications Director with American Rivers, a nonprofit organization that works to ensure the health and vitality of waterways in the U.S. "Today there’s over 40 million people in the basin, with a 100-year-old framework dividing the river."

Those states--and some of the Indigenous tribes in and near the river basin--use water from the Grand Canyon to sustain agriculture, for drinking water, and to exist, really. The water rights issue has been hotly contested for decades, and the situation is becoming more dire.

"You have an over allocated river to begin with,” says Eberle. “You have a sharply growing population and you have 20 percent less water. The bank account is over tapped."

The recent agreement among the Lower Colorado River basin states should help, as they've all vowed to make cuts in how much water they use. But since the agreement ends in 2026, long-term solutions are still required in order to keep the river flowing.

277 Miles of Sand

Aside from sustaining life in the southwest, the river is sacred to at least 11 Indigenous cultures who have lived in and around the canyon. (The Havasupai, Halaupai, Navajo, and Pauite remain in the greater area.) The Colorado River carries with it the history and spirit of Native American life. The river also carries sand, which protects archaeological sites from erosion. “Without [it], they would be exposed, and they would erode and deteriorate. And people would go see them and mess with them," says Eberle.

Sand is important for recreation, as well, because it forms and reinforce beaches along the shores of the river. Without the beaches, there'd be no place for boaters to camp each night.

The U.S. Bureau of Reclamation controls the flow of water out of Lake Powell through Glen Canyon Dam in Northern Arizona into the Grand Canyon. (And, surprise, Lake Powell's water levels have become frighteningly low.) "The dam blocks 99% of the sediment going downstream," says Buma, "which currently contributes to erosion and a lot of these archaeological sites are getting hammered."

Eberle says the majority of sand that enters the Colorado River in the canyon comes from the tiny Paria River, but most of that sand just "sits in front of the Paria." The Bureau of Reclamation occasionally orders a high-intensity, short-duration flood--a large release of water through Glen Canyon dam meant to move the sand downriver through the Grand Canyon, which helps rebuild beaches and sandbars. The Bureau orchestrated a 72-hour event like this in April 2023, the first of its kind since November 2018. Ideally, these high-intensity, short-duration floods would happen more often, but in recent years there just hasn't been enough water to make it feasible.

A healthy, flowing river also scours the vegetation along the shores of the beaches--a good thing for rafters. "If they're not scoured out, there's just vegetation that encroaches on the beaches," says Eberle. So even if the Colorado continues to flow through the canyon, a reduction in water overall could mean more vegetation and less room for boaters to camp.

How Recreation Could Change at the Grand Canyon

The National Park Service limited the size of rafting trips back in 2006 due to shrinking beaches along the shores of the river. Since then, a handful of forced flows out of Glen Canyon Dam have kept restrictions at bay; beaches have come and gone.

Luckily for those wanting to run the river as it diminishes in size, there's no "magic level" that will preclude rafting, according to Janet Balsom, Chief of Communications, Partnerships & External Affairs Office of Grand Canyon National Park. The National Park Services says that the river flows between 8,000-25,000 cubic feet per second (CFS), and Balsom has run the river when it was at a mere 2,500 CFS. "Boaters will find a way, even if it's in a Sportyak" (a small dinghy), she says.

If the river dries up entirely, rafting will obviously become impossible, as will the need for sandy camping beaches.

Aside from providing a watery playground for boaters, the river also currently serves as a cooling station for hikers, backpackers, and those seeking FKTs running Rim to Rim (or Rim to Rim to Rim). Trail users in the canyon rely on drinking water from seeps and springs in the area, which, according to Balsom, haven't shown diminished levels similar to the Colorado River. "Although," she adds, "that's one of the areas where we wish we had more information."

But without a river, foot travelers wouldn't be able to dunk and refresh once they reach the bottom, and the entire canyon would run hotter. The absence of moving water would increase temperatures at an unknown percentage, while a decreased number of trees and shrubs (shade) would turn up the heat as well. The hottest place in the canyon, Phantom Ranch, has already recorded temps of 120 degrees Fahrenheit on several summer days.

And bikes, which aren't allowed beneath the rim now, still wouldn't be allowed beneath the rim if the river dried up, says Balsom. "It really is about safety and non-compatible uses," says Balsom. "Can you imagine bikes interacting with mules and hikers? And the medicals that would ensue?"

But beyond how we enjoy the Grand Canyon potentially changing, a trickle of a river creates a massive crisis for ranchers, farmers, cities, and millions of people who utilize water, energy, and food grown from a flowing Colorado River. And it would jeopardize the preservation of cultural landmarks and spiritual heritage of the 11 associated Indigenous tribes who consider themselves directly tied to Grand Canyon.

For now, stakeholders from every angle are working to find a solution for the canyon and the Colorado River that runs through it. "Our ultimate responsibility is the preservation of the resources as unimpaired as they can be," says Balsom on behalf of the National Park Service. "And visitor uses are really secondary, because if you don’t maintain the integrity of the resource, you’re not going to have the visitor experience you want."

"Water is everything," adds Buma. "And we can't make water. We can make all sorts of things, but we can't make water. We just can't."

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