Can the Colorado River keep on running? – National Geographic
The Colorado River is being sucked dry by cities and farms and is also suffering the effects of climate change. What will it take to save the “lifeline of the West”?
Maybe you’re brushing your teeth; perhaps you’re rinsing your dishes; you could be watering your plants. When you turn on your faucet in parts of Wyoming, Colorado, Utah, New Mexico, Nevada, Arizona, or California, there’s a good chance you’re drawing water from the Colorado River. But the days of this mighty waterway may be numbered, along with the free-flowing access to freshwater from the faucet for one in ten Americans that it affords. The average annual flow of the Colorado River has decreased 19 percent compared to its 20th century average. Models predict that by 2100, the river flow could fall as much as 55 percent. The Colorado River, and the people it sustains, are in serious trouble.
Winter snow falls on the high peaks of the Rocky Mountains, settling in deep drifts until the spring thaws melt the snowpack to steadily release millions of gallons of freshwater that cascades downstream and into the Colorado River, which flows 1,450 miles through seven states, carving the iconic canyons of the American West, until finally reaching the Gulf of California. At least, that’s how it had been for millennia― but not anymore. The Colorado River no longer reaches the Gulf, and instead peters out of existence miles short of the sea. Two factors have conspired to turn this once mighty river into a trickle: climate change and overuse by the very states that rely on its waters.
A section of the Colorado River. Over 40 million people in the U.S. and Mexico rely on this great American river for water, but by 2022 there’s a 68 percent chance Lake Mead, one of the river’s largest reservoirs, will experience a serious shortfall.
The Colorado flows through sweeping pasturelands and deep mountain gorges before entering semi-arid and arid landscapes from which it receives little water. Since it was first charted by John Wesley Powell 150 years ago, the river has seen colossal changes along its rocky banks, including construction of three major dams, a population explosion, agricultural development, and the emergence of energy production. But this “lifeline of the West” is now straining under the burden of climate change: for nearly two decades the Colorado Basin has been in drought with decreasing precipitation and rising temperatures. A declining snowpack now thaws earlier and faster, and these changes have further strained the river’s water supply. Experts are no longer talking about a temporary (if prolonged) state of drought in the Colorado River Basin: they refer now to a permanent state of aridification.
This landscape near Denver, Colorado, highlights a state of extremes: the declining snowpack of the Colorado Basin and decreasing levels of precipitation are contributing to aridification―an exceedingly water-scarce environment.
But climate change is not the whole the story, we are also overusing what water there is. It’s easy to understand how early planners never imagined that the water could run out. In 1922, when the Colorado River Compact was negotiated, and the river’s water was divided up for use among the seven states that comprise the river’s upper and lower basins, the total annual flows of the Colorado River that were used to calculate states’ portions were unusually high. Maybe too high, because today the Lower Basin states have long exceeded their allocations, and must tap into reservoir reserves to top up. In addition, the population of the basin is nine times higher than it was in 1922, and the cities that depend upon the river for water, including Los Angeles, Las Vegas, Denver, and Phoenix, have grown even more. Two thousand people called Las Vegas home in 1922; today, the city is home to nearly two million residents. Demand for the Colorado River’s water has outstripped supply for the past two decades.
This deficit threatens the freshwater supply of some 40 million people and the food security of the whole nation: water from the Colorado River is used to grow 90 percent of the nation’s winter vegetables. The Colorado River Basin drives a $1.4 trillion economy—if the 242,000-square-foot basin were its own country, it would be the world’s seventh largest by economic output. But providing freshwater to growing cities and farms carved out of an unforgiving landscape (around 70 percent of the river’s water is used for irrigation) is not sustainable. And the signs are visible: in 2018 the levels of the Blue Mesa reservoir dropped below one-third its capacity, revealing the foundations of a town not seen since it had been flooded to create the reservoir in 1966.
In an effort to avert catastrophe, in May 2019 representatives from seven states and the federal government signed the Colorado River Drought Contingency Plan (DCP) with the collaborative goal of reducing risks to water supplies. In the short term, Upper Basin states have committed to sending water downstream to top up the important Lake Powell Reservoir if it drops to critical levels, and Lower Basin states are introducing new water conservation measures to reduce their withdrawals and, hopefully, prevent unprecedented shortages and the need for dramatic cuts.
Dillon Reservoir in Summit County, Colorado. In order to avoid dramatic water use restrictions in the future, water authorities in the Colorado Basin are introducing new conservation measures to ease stress on reservoirs.
The average American family uses over 300 gallons of water every day, and significant water savings can be made. Around 10 percent of homes have easy-to-fix leaks that waste 90 gallons a day or more, and we would use around 20 percent less water if we installed water-efficient fixtures and appliances, from faucets and showerheads to using washing machines and dishwashers. Pre-rinsing dishes before loading them into the dishwasher wastes at least 20 gallons of water per load, so we can actually save more by doing less.
In 2019 something extraordinary happened: after two decades of drought, strong storms, persistent precipitation, and cold temperatures resulted in overflowing rivers that began recharging Colorado’s reservoirs. The state was 100 percent drought free for the first time in 19 years. But it didn’t last―by August 2019 drought had returned. It’s estimated that another 13 extraordinary water years would be necessary to erase the impacts of long-term drought in the West. We can’t rely on Mother Nature to solve this problem; we have to solve it ourselves. With abundant rainfall and a new water management plan, 2019 was a good year for the Colorado River. And if Americans pitch in to conserve more water across farming and industry sectors and at home, these efforts could herald a turning point for the Colorado and other rivers―and the people who rely on them.
