Rainy weather has hit the West this winter. “Atmospheric River” battered california with weeks of heavy rains, and the Rocky Mountains are covered in snow. That’s good news for the Colorado River, where all that moisture hints at a possible spring rise in massive drought-hit reservoirs. Climatologists, however, say the 40 million people who use river water should take the good news with a grain of salt.
The flakes that accumulate high in the Rocky Mountains are critical to the Colorado River, the waterway of human life from Wyoming to Mexico in an area commonly referred to as the Colorado River Basin. Before water flows through rivers, pipelines and canals to towns and farms throughout the region, it begins as high mountain snow. More than two-thirds of the river in Colorado starts with snow. Overall this year is well above average, but climatologists say there’s plenty of winter left.
“Everyone is so eager to get this done as early as possible,” said Brad Udall, a water and climate researcher at Colorado State University. “You’re bound to get caught with your pants down if you think you know what’s going to happen.”
The Colorado River is in crisis, shrinking as a result of climate change. The 23-year “mega-drought” created the region’s driest conditions since about 200 AD. multi-billion dollar agricultural sector and major cities such as Denver, Phoenix, Salt Lake City, Las Vegas, and Los Angeles, which depend on river water.
Increasing attention is now being paid to the snow-capped mountains that keep the river flowing and help fill the country’s two largest reservoirs, Lake Mead and Powell. These reservoirs have fallen to historic lows – endangering hydropower for millions of people and threatens to expensive modifications to the towering dams that hold back the water.
Meanwhile, the total amount of snow in the mountains is starting promisingly. In the Snowmass area, snow cover is 130% above average for this time of year. The Roaring Fork Watershed, which includes Aspen and Snowmass, makes up only 0.5% of the land mass in the Colorado River basin but provides about 10% of its water.
Other nearby mountain ranges have total snowfall between 140% and 160% above average. Even if those numbers hold up until spring, the severity of the Colorado River drought means it will take many more years of heavy snowfall to cause serious damage.
“It’s nice to see a lot of snow,” Udall said. “It will take us five or six years with 150% snow cover to fill these reservoirs. And that’s highly unlikely.”
A succession of rainy years is unlikely due to rising temperatures caused by climate change, Udall said. Since 1970, temperatures in the Colorado River basin have risen by three degrees Fahrenheit. These higher temperatures have already caused a 15 percent reduction in river flow in the region.
The warming has led to many disturbing changes in the environment by region. In recent years, scientists have been sounding the alarm about the drying up of soils. The earth dried up and absorbs melting snow before the water can reach the places where people divert and collect it.
Winters with 90% average snow cover have already led to springs with 50% runoff, Udall says, because the thirsty soil acts like a sponge.
Even the concept of “average” has changed due to warming temperatures. Spring 2021 National Oceanic and Atmospheric Administration the way the averages are calculated has changed for all his data.
Every 10 years, NOAA moves the three-decade window it uses for averages. But the rapidly accelerating effects of climate change mean the current window from 1991 to 2020 extends beyond previous 30-year periods as it includes the hottest period in American history.
Because of this, the snow cover data tells a somewhat misleading story. For example, if the snow cover is 130%, this number will be significantly lower if you compare current totals with more than 30 years of normals.
“Man, we need to keep preparing for the worst,” Udall said. This is what we have seen for the last 23 years. That’s what these warmings keep telling us.”
Planning has become much more difficult as changing baselines make the future of water availability less predictable.
Cynthia Campbell, who has advised the city of Phoenix on water law for more than a decade, knows this firsthand. This city, the fifth largest in the country, gets more than one-third of its water from the Colorado River.
“Our worst-case scenario, from our point of view, is that we should get into the habit of looking up into the mountains every year to see what the rainfall is like,” Campbell said.
Campbell said that in an ideal world, the reservoirs serve as a buffer against fluctuating dry and wet years. But when these reserves are reduced to never-before-seen lowscities in the southwest can only plan one year at a time.
“It’s just not enough time to make the changes you should be making,” Campbell said with a nervous laugh. “But this is where we are. So in a way, this could be our worst nightmare.”
The people of Campbell and Phoenix are not alone in their hand-wringing.
As supply shrinks, the seven states that use water from the Colorado River are facing a standoff over how to cut demand.
The distribution of water across the basin is governed by a 1922 legal agreement that has not been substantially rewritten to meet the needs of the changing region. Some experts suggest this agreement – the Colorado River Agreement – must be replaced to meet the modern needs of the region with vast fields of agricultural crops and rapidly growing urban population.
As the drought worsened, states agreed to a patchwork of band-aids to prop up reservoirs and avert disaster, but could not agree on larger, more permanent cuts.
AT meetings about the future of the riverdelegates from seven states, including Colorado, Utah, Arizona and California, are quick to talk about the need to work together to solve their collective problem, but reluctant to commit donate some of your shares.
The current rules for managing the river expire in 2026, and until that time, the states are mainly focused on drafting a new agreement. Policy analysts and water managers have hinted that the bulk of the cuts will have to come from the agricultural sector, which uses more than 70% of the Colorado River’s water.
In the meantime, cities have been ingenious in stretching finite amounts of water over growing populations. Those efforts have not been altered by heavy snowfall in the mountains this winter or weeks of rain that flooded California, causing major flooding and damage.
“One storm won’t make a difference whether we have a rainy year or not,” said Adel Hagehalil, general manager of the Southern California Metropolitan Water District. “We need to continue to focus on building the infrastructure needed to provide local water supplies.”
The area supplies drinking water to 19 million people from north Los Angeles to the Mexican border. The agency has undertaken a number of ambitious projects to reuse water that is already in the system.
One proposed facility in Carson, California will be purify waste water make it drinkable. The treatment facility is projected to cost $3.4 billion to build. Once completed, it will cost $129 million a year to operate. This new facility is designed to divert up to 150 million gallons back to the municipal water supply in and around Los Angeles.
Water agencies in Nevada and Arizona plan to get involved by helping pay for the project in exchange for some of the water in Southern California. The hefty price tag is just one example of many spending on new infrastructure cities can suffer due to climate change.
“We have to be ready,” Hagehalil said, “and it will be on us if we take the right actions today to invest and build the necessary infrastructure.”
Elsewhere in the Colorado River basin, governments are teasing the idea of investing in other ways to increase existing water supplies. Last year, then-Arizona Gov. Doug Ducey proposed to Mexico a deal where the state would fund sea water desalination plant on the Gulf of California. This would allow Mexico to use newly desalinated water in exchange for a portion of Mexico’s share of the Colorado River.
Ingenious solutions such as wastewater reuse and desalination have sparked a stir among residents of the region’s scorched cities, but water policy analysts say none of them can serve as a silver bullet for those dependent on the drying up Colorado River. Instead, they say, a significant reduction in demand is the only way to address the impacts of climate change on water supplies.
This story is part of an ongoing coverage of the Colorado River produced by KUNC in Colorado and supported by the Walton Family Foundation. KUNC is solely responsible for its editorial coverage.
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