Top Colorado water officials this week highlighted the uneven use between the Upper and Lower Colorado River Basins and some suggested the vast majority of reductions needed to rebalance a system in which use far outpaces supply would have to come from the Lower Basin.
New data released Tuesday by the Upper Colorado River Commission, an interstate agency that manages water in the Upper Basin, shows that in 2021, drought and other climate factors reduced the amount of water available in Colorado, New Mexico, Utah and Wyoming by about 1 million acre-feet compared with the previous year. During that same time, according to the UCRC data, water use increased in the Lower Basin.
“Those provisional numbers show the Upper Basin used 25% less water in 2021 than it did in 2020,” Colorado River Commissioner Becky Mitchell said at an UCRC meeting Tuesday at the state capitol in Wyoming. “That is a huge number, especially when we’re talking about a smaller piece of the Colorado River pie.”
Also on Tuesday, Bureau of Reclamation Commissioner Camille Touton warned Congress that Colorado River water users must cut their water usage by as much as one-fourth by the end of next year to address “critically low water levels” and prevent depleting the reservoirs past the point at which they can continue to function and produce hydropower.
Speaking to the Senate Committee on Energy and Natural Resources, Touton said that the bureau will work with the seven Colorado River basin states and the tribes to come up with a plan during the next 60 days to reduce use across the basin by between 2 million and 4 million acre-feet. Touton cautioned that, if necessary, the bureau has the authority to “act unilaterally” to protect the system, which supplies water and generates electricity for millions of users across the West
According to the new UCRC numbers, total Upper Basin water use, including water lost to evaporation, added up to about 3.5 million acre-feet in 2021, a provisional number. That number was about 4.5 million acre-feet the previous year. The UCRC numbers show 2021 water use plus evaporation losses in the Lower Basin — California, Arizona and Nevada — at nearly 10 million acre-feet, which includes about a 1.5 million acre-foot portion for Mexico.
Water users in Colorado have already been getting by with less, said Andy Mueller, general manager of the Colorado River District. “No one got paid not to use water; no one enrolled in a federal program not to use water; this was water that was either legally or physically not available primarily at our rancher’s and farmer’s headgates in 2021,” he said. “They are doing what the commissioner has asked; they have reduced their use.”
Colorado and the other Upper Basin states do not have the benefit of massive reservoirs above them to hold water and instead rely on the runoff that’s available each year. Climate factors such as drought and dry soil have made that runoff less reliable. Scientists predict the amount of water that will flow into Lake Powell this spring and summer to be 59% of average.
“Colorado water users are on the front lines of climate change,” Mitchell said in a statement.
In the Lower Basin, water users can pull water from the country’s two largest reservoirs, Lake Powell and Lake Mead. However, those reservoirs have been significantly depleted during the current megadrought, which scientists believe is the driest 22-year stretch during the past 1,200 years. The lakes are now both less than 30% full.
“When you have low runoff in the Upper Basin that means that the water users who normally have water late in the year don’t,” said Chuck Cullom, executive director of the Upper Colorado River Commission. He noted that the poor runoff in 2021 reduced supply available primarily to farmers and irrigators. “Folks with a junior priority who would normally have water available in August had to shut off in July.”
For example, Cullom pointed out that last year the Ute Mountain Ute Tribe Farm & Ranch Enterprise in southwest Colorado received only 10% of its normal water supply.
Mitchell noted that Colorado and the Upper Basin states have contributed 661,000 acre-feet the past two years to help protect Lake Powell from falling below 3,490 feet above sea level, the minimum elevation required for Glen Canyon Dam to generate power. This year, 500,000 acre-feet will be released from Flaming Gorge on the Utah-Wyoming border. In 2021, the Department of the Interior pursued emergency action that included releasing 36,000 acre-feet from Blue Mesa near Gunnison and 125,000 acre-feet from Flaming Gorge.
Mueller said that in the case of federal reclamation projects that supply water to Colorado water users such as the Dolores Project in southwest Colorado and others there are emergency provisions in the contracts that could allow the federal government to reduce an allocation to those projects.
“Is the commissioner talking about reducing use in the Upper Basin?” Mueller said. “She might be. Given the imbalance of where the water is being taken out and used right now that would be very hard to stomach.”
Anne Castle, a senior fellow at the Getches-Wilkinson Center at the University of Colorado Law School, said that the numbers commissioner Touton spoke about to Congress are significant.
“People have been thinking along the lines of solving a 2 million acre-foot deficit problem but the range from 2 million to 4 million is a big range. Four million is almost infinitely harder than 2 million,” Castle said. “Those numbers are so big I don’t see that that gap can be bridged by one basin alone; it can’t be bridged by one sector alone, like the agriculture sector.”
In Colorado, agriculture uses about 85% of the water statewide.
Steve Pope, general manager of the Uncompahgre Valley Water Users Association, one of the state’s largest diverters of irrigation water, said the commissioner’s testimony concerns him. The association manages the water that comes out of the Gunnison Tunnel, a federal project.
“How do you get more blood from a turnip,” Pope said. “There is no Upper Basin storage. How are we going to come up with it?”
Denver Water CEO Jim Lochhead said significant reductions in demands on the river should have started several years ago. Denver Water gets about half of its supply from the Colorado River system.
“Everyone is going to have to contribute to solving the problem,” Lochhead said in a statement, “but the vast majority of reductions are going to have to occur where the vast majority of water use has occurred — in the Lower Basin.”
Ken Curtis, general manager of the Dolores Water Conservancy District, which manages the Dolores Project, said this year they’re already operating on about a 30% supply.
“In some ways we’re already doing forced conserved consumptive use,” Curtis said. “They just have different opportunities given the plumbing down in the Lower Basin versus it coming right down off the mountains and off it goes.”
Mueller said the Upper Basin can also manage demands better. He said marginal land that didn’t get irrigated in the past few years would probably need to stay out of production for the foreseeable future. But, he said, the majority of the 2 million to 4 million acre-feet Commissioner Touton cited needs to come from the Lower Basin.
“It’s time they reduce the flow out of the Hoover Dam, which means the Lower Basin has to cut their use. Period,” Mueller said. “Oddly enough, the Bureau of Reclamation runs the facility that has allowed it to be that way.”