Aerial view of Boulder Basin, the northwestern arm of Lake Mead, shows the bathtub ring, indicator of long-term water loss, between Boulder City, Nevada, and the Las Vegas metropolitan area on July 3, 2025. Photo by Daniel Slim, AFP via Getty Images
In summary
California shoots pointed words at states upriver, as negotiators struggle toward sharing supplies. Without a deal, the Trump Administration will step in.
After one of the Colorado River’s driest years in decades, Lake Mead and Lake Powell — the largest reservoirs in the country — could see alarming declines in the coming years, the U.S. Bureau of Reclamation announced today.
Federal officials again called for Arizona and Nevada to cut back their supplies from the overtapped river — though California, with its senior claims to the river’s water, will be spared.
While expected, today’s two-year projection ratchets up tension among seven states in the Colorado River basin, which have struggled to agree on the river’s management after 2026, when current guidelines expire.
“The urgency for the seven Colorado River Basin states to reach a consensus agreement has never been clearer. We cannot afford to delay,” Scott Cameron, the Department of the Interior’s Acting Assistant Secretary for Water and Science, said in a statement.
Lower-basin states — California, Arizona, and Nevada — are at odds with upper-basin states — Colorado, Wyoming, Utah and New Mexico — as they negotiate over dwindling water supplies.
“We’re really sort of staring at what the deal is right now. But as close as it is, the harder it gets,” J.B. Hamby, California’s chief negotiator as chairman of the Colorado River Board of California, told CalMatters.
Hamby also directed pointed words toward the upper-basin states.
“The future of the Colorado River cannot rest on our shoulders alone. We have to ensure that every part of the basin takes responsibility for protecting the river’s future,” he added, in a statement.
Becky Mitchell, Colorado’s commissioner to the Upper Colorado River Commission, countered in an email: “If the lower basin is able to join us in adapting to a drier river, a basin states consensus is likely.”
Federal officials have warned that basin states must hash out the broad strokes of an agreement by Nov. 11, or risk the U.S. government imposing its own.
Interior Secretary Doug Burgum is “not looking forward to that,” Cameron warned at a June conference. “But in the absence of a seven-state agreement, he will do it.”
The stakes for California are high. California takes the biggest share of Colorado River water — largely to irrigate half a million acres of alfalfa, winter vegetables and other crops in the Imperial Valley, and also to supply urban Southern California via the Metropolitan Water District. More than half of the power generated at Lake Mead’s Hoover Dam goes to California.
As negotiators haggle over a seven-state deal, California water suppliers are also in parallel talks about how to share future shortages amongst themselves and with Arizona, said Bill Hasencamp, Metropolitan Water District’s manager of Colorado River resources.
Plunging water levels at Lake Mead and Lake Powell only make that harder, he added.
“Even with all of our efforts to do record amounts of conservation, it’s still not enough,” Hasencamp said. “We have to do even more than we’ve been doing in dry years.”
Demand has long outstripped supply, and climate-fueled megadrought and aridification have starved the river in recent decades — drying up the equivalent of Lake Mead by 2021.
By the summer of 2022, the driest 23-year stretch in over a century had sent the river’s massive reservoirs plunging to historic lows. It was a crisis for the basin, prompting the Biden administration to call for emergency cuts or face federal intervention.
Negotiating a deal is hard enough, said Tina Shields, water department manager of the Imperial Irrigation District, which receives the largest share of California’s Colorado River water. Worsening conditions mean “you have to do a lot more sooner rather than later. It doesn’t make it impossible, but it makes it more challenging.”
The reservoirs, each only 31% full, are projected to remain at levels in the coming year that trigger 18% cuts to Arizona’s total allotment, 7% to Nevada’s, and a 5% reduction for Mexico.
Federal officials today released multiple different scenarios for the next two years. The one that experts say is most likely shows that one more dry year could send Lake Powell plunging below the levels needed to generate power by December 2026.
The problem is that as climate change drives temperatures higher, thirsty soils drink up runoff before it reaches the river. Though precipitation reached 80% of average in the upper basin this year — and the snowpack hit 92% of the median at the end of March — spring runoff into Lake Powell was only 41% of normal.
Brad Udall, a senior water and climate research scientist at Colorado State University’s Colorado Water Institute, told CalMatters that the situation is “beyond awful.”
“I’m still optimistic that we’re going to pull a rabbit out of the hat at the last minute … although there are mumblings that things are not going so well, ” he said.
Now, under the Trump administration, a new proposal to allocate a certain percentage of the river’s average flow to each basin is coming together, according to Hamby, California’s negotiator. Under the proposal, the lower basin and Mexico would receive some as-yet unknown percentage between 55% and 75% of average flow.
The question that must be answered by November is what that percentage should be.
“In our case, it would be an agreement to live with less than we’re otherwise entitled to,” Hamby said. And the upper basin states, he added, “may actually have to do something wild and crazy, like conserving water sometimes.”
Becky Mitchell in Colorado said that the water users in the upper basin already reduce their use during drier years, with shortages averaging 1.3 million acre-feet per year.
Moving forward with a plan, she said, “will depend upon the specifics.”
If current policies aren’t updated, the reservoirs are highly likely to reach deadpool — the level at which water can no longer be released — at least once in the coming decades, according to a soon-to-be published study.
“There’s a risk of these reservoirs dipping into lower water levels that can make them inoperable,” the study’s lead author Benjamin Bass, a researcher at UCLA’s Center for Climate Science, told CalMatters. “That’s really why we need to shift away from existing policy to something more stringent.”
Rachel Becker is a journalist reporting on California’s complex water challenges and water policy issues for CalMatters. Rachel has a background in biology, with master's degrees in both immunology and... More by Rachel Becker
Republish
‘Beyond awful’ Colorado River forecasts put water talks under pressure
We love that you want to share our stories with your readers. Hundreds of publications republish our work on a regular basis.
All of the articles at CalMatters are available to republish for free, under the following conditions:
Give prominent credit to our journalists: Credit our authors at the top of the article and any other byline areas of your publication. In the byline, we prefer “By Author Name, CalMatters.” If you’re republishing guest commentary (example) from CalMatters, in the byline, use “By Author Name, Special for CalMatters.”
Credit CalMatters at the top of the story: At the top of the story’s text, include this copy: “This story was originally published by CalMatters. Sign up for their newsletters.” If you are republishing commentary, include this copy instead: “This commentary was originally published by CalMatters. Sign up for their newsletters.” If you’re republishing in print, omit the second sentence on newsletter signups.
Do not edit the article, including the headline,except to reflect relative changes in time, location and editorial style. For example, “yesterday” can be changed to “last week,” and “Alameda County” to “Alameda County, California” or “here.”
If you add reporting that would help localize the article, include this copy in your story: “Additional reporting by [Your Publication]” and let us know at republish@calmatters.org.
If you wish to translate the article, please contact us for approval at republish@calmatters.org.
Photos and illustrations by CalMatters staff or shown as “for CalMatters” may only be republished alongside the stories in which they originally appeared. For any other uses, please contact us for approval at visuals@calmatters.org.
Photos and illustrations from wire services like the Associated Press, Reuters, iStock are not free to republish.
Do not sell our stories, and do not sell ads specifically against our stories. Feel free, however, to publish it on a page surrounded by ads you’ve already sold.
Sharing a CalMatters story on social media? Please mention @CalMatters. We’re on X, Facebook, Instagram, TikTok and BlueSky.
If you’d like to regularly republish our stories, we have some other options available. Contact us at republish@calmatters.org if you’re interested.
Have other questions or special requests? Or do you have a great story to share about the impact of one of our stories on your audience? We’d love to hear from you. Contact us at republish@calmatters.org.
Gift this article
Low Water Levels Threaten Colorado River Talks
Federal forecasts about the drying Colorado River are raising tensions among 7 states, who are trying to beat a deadline for negotiations.
CalMatters
California, explained
Rachel Becker
Rachel Becker is a journalist reporting on California’s complex water challenges and water policy issues for CalMatters. Rachel has a background in biology, with master's degrees in both immunology and science journalism. She previously reported on climate change and air pollution for CalMatters, and contributed to early coverage of the COVID-19 pandemic, as well. Before joining CalMatters, Rachel was a staff reporter at The Verge, and her byline has also appeared in outlets including National Geographic News, Smithsonian, Slate, Nature and the YouTube series MinuteEarth.