New rules for the Colorado River officially go into effect on Thursday, but they won't bring changes to Arizona's water quite yet. The state is still working on a three-way deal with California and Nevada to spread out the pain of water cutbacks. Arizona's water cuts will become official on Jan. 1, 2027, and Arizona's top water negotiator told KJZZ he's "very optimistic" about progress on the three-state deal that must be signed by then.
To understand the complicated timeline for new water rules, it helps to take a step back and look at the Colorado River's complicated calendar.
Federal rules for the Colorado River and its major reservoirs typically run on a different calendar than the rest of the world. The "water year" runs from Oct. 1 to Oct. 1. So, starting Thursday, a controversial federal plan will start changing the amount of water sent from Lake Powell downstream to Lake Mead.
However, the amount of water delivered from Lake Mead to people farther downstream — like cities in the Phoenix area and huge farm districts in California — is managed in line with the normal calendar, from Jan. 1 to Jan. 1.
So even though the amount of water flowing into Lake Mead will be different this week, the amount of water flowing out of it won't change until the beginning of 2027.
The three states that pull water from the Colorado River downstream of Lake Mead — Arizona, California and Nevada — have until the new year to formalize an agreement that is designed to run in parallel with the new federal rules. The federal plan places the significant majority of cutbacks on Arizona, and the other two states have offered to shoulder some of that burden instead of letting it fall so heavily on Arizona.
What's the main holdup?
When the federal government announced its new plan in August, leaders from those three states talked about their side deal in fairly certain terms. However, a few things have gotten in the way since then, leaving the agreement in limbo.
The first is the complicated process of figuring out which cities and farms, specifically, will be using less water going forward.
"It's kind of been the story of the Colorado River for many years now," said John Berggren, a water policy expert with the environmental nonprofit Western Resource Advocates. "The people negotiating these agreements reach a high-level agreement of 'Here's what we're willing to do,' and then they have to go back and shop it around their state and make sure they can get their water users on board with what they are tentatively agreed to."
Tom Buschatzke, Arizona's top water negotiator, said Arizona and Nevada have plans in place, and California is "working out final details" on how to cut back enough water across some of its largest users. That includes the Metropolitan Water District of Southern California, which serves about 19 million people in the Los Angeles and San Diego areas, and the Imperial Irrigation District, a powerhouse farming region that uses more Colorado River Water than any other entity.
Buschatzke said states are "putting all the final touches" on the agreement before sending it to the boards of those organizations and others in the participating states.
"It's more dotting I's and T's," he said. "I'm very optimistic, based on recent discussions, that we're going to close on the agreement language in a way that it will be then ready to go to various boards over the next few weeks."
Nevada's lawsuit
Also complicating the three-state deal was a bombshell legal action. Nevada caught many by surprise when it sued the federal government over its new river rules, arguing that the Interior Department failed to check certain legally-required boxes while drawing up its new strategy.
The lawsuit is still working its way through the legal system, but may have slowed down negotiations between Nevada and its allies.
"People are interested in waiting to see how the federal government responds," Berggren said, "Which we should know in the next month or so. So, depending on how they respond, I think that will dictate what other people do."
Arizona's Buschatzke indicated that the legal action played some role in talks between the three states.
"The Nevada lawsuit was something we did have to deal with in regards to the Lower Basin Agreement," he said. "It did take some time, I think, to work through how that all would fit together. But I do think there's a positive path forward to deal with the Nevada complaint and to get the Lower Basin Agreement over the finish line."
In a memo to the federal government, John Entsminger, Nevada's top water leader, wrote that his state is "committed to working cooperatively towards finalizing and implementing the Lower Basin agreement."
Arizona's Legislature
Once the three-state deal is signed by negotiators, it would also have to clear one important hurdle: the Arizona Legislature. Of the seven states which use the Colorado River, Arizona is the only one in which state lawmakers have a chance to approve or block interstate water-sharing agreements.
Earlier this year, Buschatzke told KJZZ that he wouldn't sign a three-state deal unless he was confident it would get approval from the Legislature, which may require a special session.
Since then, however, the state's water matters have surged into the political spotlight. Gubernatorial candidates Democratic Gov. Katie Hobbs and her challenger, Republican Congressman Andy Biggs, have made water issues central to their campaigns. In races all over the ballot, candidate speeches, TV ads and lawn signs have also highlighted water policy.
In early September, Republican state lawmakers asked Buschatzke's agency, the Arizona Department of Water Resources, to provide more updates on Colorado River matters, indicating that they are not getting the same updates as Governor Hobbs.
Despite the drift of water matters into partisan politics, Buschatzke still believes a three-state Colorado River deal will get bipartisan approval.
"We've been briefing the legislature quite a bit on the agreement itself and its status," he said. "I believe, at the end of the day, that the agreement will go through the legislature once we get there. It is an agreement that shows strong collaboration among the three states."
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