As a 23-year-old drought intensified by climate change and overallocation continue to endanger the Colorado River water supply, Arizona, Nevada and Mexico will face more reductions in their allotments, the U.S. Bureau of Reclamation announced Tuesday. 

According to new projections by the Department of Interior, the river’s main reservoir, Lake Mead in Nevada, will reach record low levels in January, triggering a “Tier 2a” shortage that calls for a collective reduction in Colorado River use by Arizona, Nevada and Mexico. About 80 percent of the more than 720,000 acre-feet reduction will come from Arizona. California would not be impacted by the newly declared shortage because the reductions are based on previously negotiated levels. 

“It is unacceptable for Arizona to continue to carry a disproportionate burden of reductions for the benefit of others who have not contributed,” Arizona officials said in a Tuesday statement after the shortage was announced.

A century after the apportionment of Colorado River water through the Colorado River Compact, its two largest reservoirs, Lake Mead and Lake Powell in Arizona, have reached their lowest levels, below 30 percent capacity. The Bureau of Reclamation, which oversees water resource management, declared Lake Mead’s first-ever water shortage last year, with Arizona farmers being hit the hardest with cuts. 

Almost 93 percent of the West is experiencing drought, with more than 70 percent of the West experiencing severe or extreme drought conditions. The shrinking reservoir levels have exposed human remains, sunken boats, guns and Native American ruins.

Combined storage in Lake Powell and Lake Mead, also the two largest reservoirs in the United States, is expected to reach about a quarter capacity by the end of this year. By January, Lake Powell in the Upper Basin is expected to reach just 32 feet above the minimum level required for hydroelectric power generation.

The announcement comes as Basin states—Arizona, California, Nevada, Wyoming, Colorado, Utah and New Mexico—failed to agree on how to make massive water-use cuts to stabilize reservoir levels despite pressure from the federal government. 

Bureau of Reclamation Commissioner Camille Touton said in a Senate hearing in June that water levels in Lake Mead, the river’s largest reservoir, were dropping quicker than expected, threatening water and hydropower security throughout the West. 

“The system is at a tipping point,” she warned at the hearing.

She told states to devise a plan to cut 2 to 4 million acre-feet of water by Aug. 16 to prevent Lake Mead from dropping so low that it could no longer generate hydropower or deliver water downstream. According to a report released in April, the river is the most endangered in the country. It supplies water to more than 40 million people, and more than two-thirds of the river’s water irrigates more than 5 million acres of farmland.

“It is in our authorities to act unilaterally to protect the system, and we will protect the system,” Touton told the Senate. “We need to see the work. We need to see the action. Let’s get to the table, and let’s figure this out by August.” 

Touton also warned that the Biden administration would be prepared to step in if states don’t deliver a plan by the deadline. They have 60 days, she said.

The states did not deliver, and the federal government has not outlined how they plan to make the 2 to 4 million acre-feet cuts happen.

The order that expired on Tuesday is a sign of increasing federal involvement in protecting the Colorado River, said Elizabeth Koebele, an associate professor of political science at the University of Nevada whose research focuses on water policy. The federal government calling for quick collaboration to protect levels in the two reservoirs is “not new, but the conditions are more dire,” Koebele said.

The goal is loftier, and the deadline was tighter. Jennifer Pitt, the Colorado River program director for the National Audubon Society, said that reaching a 4 million acre-feet cut is crucial for the long-term sustainability of the reservoirs.

“To get ahead of the problem, it is really important for them to be able to come up with a plan for 4 million acre-feet,” she said. “That seems pretty clear. Otherwise, we are constantly going to be chasing the problem rather than getting a little bit out of it.”

These measures would be on top of the new 2023 cuts and other conservation measures taken in response to the prolonged drought and the increasing demand for water by rising populations across the West. 

But John Fleck, a water policy professor at the University of New Mexico and former science journalist, doubted whether cutting 4 million acre-feet is possible. “4 million acre-feet is obviously out of reach,” he wrote on his blog. “It always was.”

Negotiations for how to collaboratively come up with significant emergency cuts have grown tense over the last few weeks after the federal government’s demand.

In July, the leaders of 14 Colorado River Tribal governments sent a letter to the U.S. Department of the Interior saying they “are largely in the dark about what is being discussed or whether a plan is being coalesced.”

Four days prior, the Upper Basin states—Colorado, New Mexico, Utah and Wyoming—submitted a proposal in response to the federal agency’s demand. In a letter to the federal agency, they said that while addressing the depleting shortage conditions in the river requires a collaborative effort from all states in the basin, Upper Basin state’s options to help protect the river’s elevation, per the agency’s demand, are “limited.” They said that since Lower Basin and Mexico depletions are more than double in the Upper basin, actions should be focused downstream. 

The proposal includes reauthorizing a water conservation pilot project that would compensate users for voluntarily using less water, developing a drought response framework and continuing strict enforcement of water management regulations. However, it did not mention how much water they would contribute to the federal government’s demanded reductions and how much those efforts would cost.

“Yet despite the obvious urgency of the situation, the last sixty-two days produced exactly nothing in terms of meaningful collective action to help forestall the looming crisis,” said John Entsminger, the general manager of the Southern Nevada Water Authority, in a letter to the federal government on Monday. 

In response to the Department of Interior’s Tuesday announcement, Theodore Cooke and Tom Buschatzke of Arizona said in a statement that they’ve already shown commitment to increasing Lake Mead elevation. At a press conference by the Arizona Department of Water Resources following the announcement of the shortage, they said that Arizona and Nevada had put forth a plan to achieve 2 million acre-feet of reductions among the Lower Basin and Mexico in 2023 and beyond, but California and Mexico did not support the proposal.

California’s Colorado River Board Chairman Peter Nelson issued a statement saying that even though “the Basin States have not yet agreed on a consensus-based solution to address declining reservoir elevations, California will continue implementing additional conservation programs in 2023 that result in meaningful water contributions to the system.”

The federal government’s demand and the states’ tense wrangling over the critical water supply foreshadow the ordeal of long-term management of the river. Water experts say that climate change is making predicting river levels even more difficult because of growing aridification driven by climate change.

The good news, federal officials said at the briefing on Tuesday, is that they have the resources available to take the steps necessary to save the reservoirs. On Tuesday, President Biden signed the Inflation Reduction Act into law, which includes $4 billion for the Bureau of Reclamation to respond to drought. This is on top of the $8.3 from the Bipartisan Infrastructure Law he signed last year.

“We’re bringing resources to the table in the form of infrastructure investments to help with water delivery, improvements to the system to support efficiency and support for users, including irrigators, as everybody has to tighten their belts in this situation,” said Deputy Secretary Tommy Beaudreau.

Some farmers in southwestern Arizona and southern California are coming up with a plan that would generously compensate them for reducing their water consumption. Still, some argue that plans to pay users are expensive and not sustainable.

“Much of that funding needs to go toward more durable solutions, even some things that might have lasting or even permanent impacts, not just a year at a time,” said Cooke of the Central Arizona Project.