Lake Powell is projected to stay above hydropower threshold through March 2027
After the seven Western states that rely on the Colorado River failed to agree on a plan, the Bureau of Reclamation began weighing a basinwide response. The river supplies water to 40 million people and more than 5 million acres of farmland, but drought and overuse have reduced storage in the system’s two largest reservoirs. Last month, the combined volume of Lake Powell and Lake Mead reached its lowest level since 1957.
One federal response focused on Lake Powell. In April, the bureau moved water into the reservoir from an upstream reservoir and reduced planned releases by 20%. Current federal projections show Powell remaining just above “minimum power pool” through next March, when officials expect the reservoir to be at its lowest.
Lake Powell straddles Arizona and Utah. Its dam helps provide electricity for hundreds of thousands of homes across seven Western states, and officials had expected water levels to fall below those required to generate hydropower. “Dead pool” is the level below which water cannot flow through the dam’s outlets.
The near-term action came amid exceptionally dry conditions. Record-low snowpack in many parts of the Rockies last winter left runoff into Powell far below historic averages. The dry conditions have compounded the effects of a “megadrought” that has gripped the region since 2000. Reduced river flows have led to more frequent deficits over the last 25 years.
To compensate for the deficits, officials have taken water from Powell. Years of drawing down Powell and the larger Lake Mead have taken a toll: last month, the reservoirs’ combined volume reached its lowest level since 1957, when Glen Canyon Dam was still under construction.
Jack Schmidt, director of the Center for Colorado River Studies at Utah State University, likened the recent federal measures to rearranging deck chairs on a sinking ship. “The ship continues to sink,” he said. The measures shifted water within the system rather than addressing its broader deficit.
The lack of agreement divides Colorado, Utah, Wyoming and New Mexico in the upper basin from Arizona, California and Nevada in the lower basin. Each side has insisted that the other cut consumption. Over the last 25 years, the lower basin has consumed about twice as much water on average as the upper basin. Lower-basin use has fallen in recent years, but the reduction has not been enough to steady the system.
Under the federal plan, lower-basin states could have to cut consumption by as much as 40% from allotted levels. The proposal also calls for potential reductions in releases from Powell and voluntary conservation measures by upper-basin states. Lower-basin states are awaiting details on how much they would have to reduce.
Arizona would be hardest hit because of its lower rights to the river. State officials warned, “Such reductions would devastate Arizona’s water users and its economy.” The lower-basin states have objected to the proposal.
Agriculture accounts for more than two-thirds of Colorado River consumption and potentially offers significant savings. Michael Cohen, a senior fellow at the Pacific Institute, identified “more efficient irrigation, less water-intensive crops and short-term fallowing of fields” as options. It remains unclear how effective the short- and long-term measures will be.