The U.S. Department of the Interior has released a plan to govern the Colorado River, forcing the lower-basin states of Arizona, California and Nevada into mandatory water reductions. Under the federal framework, the three states will see their collective supply cut by 1.25 million acre-feet in each of the next two years, according to denverpost.com. The rules replace previous operating plans that expire this year, concluding a planning process that began in 2022.
Federal Plan Imposes Mandatory Cuts on Arizona, California, and Nevada
The announcement follows years of tense negotiations and missed deadlines among basin states unable to reach a long-term consensus. Instead of a permanent solution, the U.S. Bureau of Reclamation released a broad 10-year framework that sets parameters for operating guidelines to be renegotiated every two years. Over the course of the decade-long framework, the three states could collectively lose up to 3 million acre-feet of water per year — roughly 40% of their annual supply — depending on future conditions.
Reservoirs Hit Record Lows Amid Persistent Drought
The intervention comes as the Colorado River system hovers near collapse after more than a century of being overdrawn. Lake Mead on the Arizona-Nevada border and Lake Powell on the Utah-Arizona line recently recorded their lowest water levels since the reservoirs were first filled. On Wednesday, Lake Mead was at 27% capacity, while Lake Powell sat at 21%.
Lake Mead measured 1,039.83 feet above sea level, nearly 190 feet below full. If it drops another 4.76 feet, the Hoover Dam will begin losing its ability to generate significant hydropower, and reaching 895 feet would trigger a complete shutdown known as dead pool. Meanwhile, Lake Powell reached a historic low of 3,519.8 feet above sea level on Sunday. Glen Canyon Dam faces similar hydropower threats if it falls to 3,490 feet, with dead pool reached at 3,370 feet.
Upper Basin States Face No Mandatory Reductions
While the federal government has the authority to mandate cuts in the lower basin, it lacks similar power over the upper-basin states of Colorado, New Mexico, Utah and Wyoming. As a result, Coloradans’ share of the Colorado River will remain unchanged for at least the next two years. Upper-basin states have historically taken far less than their formal allocations, using about 4 million acre-feet annually, and resisted mandatory cuts while arguing lower-basin states are responsible for reservoir drawdowns.
Lower-basin states will bear the brunt of the initial phase, with Arizona poised to see the biggest cut in its history across the Central Arizona Project canal and aqueduct system because it holds the most junior water rights. JB Hamby, California’s top Colorado River negotiator and chairman of the Colorado River Board of California, described the record of decision and guidelines as providing some badly needed near-term certainty at a moment of extraordinary risk.
Experts Warn of Ongoing Risks and Future Uncertainty
Despite providing immediate parameters, experts caution that the federal rules are merely a stopgap. Anne Castle, who chaired the Upper Colorado River Commission during the Biden administration, noted that the framework ensures that we will be in a state of constant negotiation over the next two-year deal.
Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University, stated that the plan requires significant belt-tightening but covers only about half of what studies suggest is necessary to bring demand in line with dwindling supply, increasing the likelihood of steeper cuts in future two-year cycles.
