Energy & Environment

Lower Colorado River Basin states submit competing water conservation plan as deadline looms

The Colorado River in the upper River Basin is pictured in Lees Ferry, Ariz., on May 29, 2021.

The Colorado River’s Lower Basin states published a proposal Wednesday for the watershed’s long-term operations, just hours after their Upper Basin peers unveiled a rival offer — and as talks between the two key contingents founder ahead of a looming federal deadline.  

The vying proposals pertain to the forthcoming update of the Colorado River’s 2007 Interim Guidelines for Lower Basin Shortages, which are set to expire at the end of 2026. These rules will govern future conservation policies for the 1,450-mile river, which serves as the lifeblood for about 40 million people in the U.S. and Mexico.  

“The Lower Basin states have set forth what we believe is the most ambitious conservation effort ever — designed with a goal of maximizing the long-term health and stability of the river system,” Tom Buschatzke, director of the Arizona Department of Water Resources, said at a press conference. 

The basin’s states — Arizona, California and Nevada — presented a proposal Wednesday that recognizes their contribution to the deficit of usable water across the Colorado River system but also strives to make cuts across the entire watershed.  

The Upper Basin states of Colorado, Wyoming, Utah and New Mexico, meanwhile, released a plan that they say would better reflect real-time hydrological conditions in a region that depends on mountain snowpack for its water supply. 


The two cohorts filed their separate submissions to the federal Bureau of Reclamation, which is overseeing the revision of the interim guidelines in compliance with the National Environmental Policy Act (NEPA). As part of the NEPA process, the agency must conduct a comprehensive analysis of proposed alternatives within an environmental impact statement (EIS). 

The bureau granted the Colorado River’s seven basin states until Monday to submit a consensus-backed alternative for consideration — warning that if this does not occur, federal officials could proceed independently, with the intention of publishing an EIS by December

The states were previously able to reach an agreement on short-term measures to tide the region over until 2026 after a year of discord, which the bureau announced it would back earlier this week. 

But no such consensus appeared within reach on longer-term guidelines Wednesday, as the two basins pushed for vastly different plans of action ahead of Monday’s deadline. 

One of the key differences between the Lower Basin proposal and that of the Upper Basin is the former’s inclusion of not only Lake Powell and Lake Mead — the watershed’s largest reservoirs and the only ones involved in the 2007 guidelines — but also five other smaller reservoirs in its calculations of storage capacity. Three of those five units are located in the Upper Basin.  

The plan, Buschatzke contended, offers “framework for system-wide, shared responsibility for the health of the system that will protect the Colorado River from Wyoming to Baja California.” 

The Upper Basin commissioners did offer to consider new storage initiatives in some of these reservoirs, but they did so only as part of possible “parallel activities” and not under the official umbrella of the federal NEPA process. 

The Lower Basin proposal, on the other hand, focuses on how these seven reservoirs could provide more than 58 million acre-feet of possible system storage. 

For reference, a 1922 compact allotted 7.5 million acre-feet of water annually to each of the two U.S. basins, while the Mexican Water Treaty of 1944 then granted an additional 1.5 million acre-feet to Mexico. A typical suburban U.S. household uses about an acre-foot of water each year. 

When considering the domestic 15-million-acre-foot total, the Lower Basin proposal suggested that there be no usage reductions when the seven reservoirs were collectively about 70 percent full.  

But if those levels slid to between 58 and 69 percent capacity — the “initial reduction” zone — the Lower Basin states and Mexico would begin instituting incremental cutbacks, of up to 1.5 million acre-feet at 58 percent, per the proposal. Arizona would bear the lion’s share of the conservation, with California — the watershed’s most senior rights holder — only making reductions after a certain threshold.  

If system contents in the seven reservoirs dropped to between 38 percent and 58 percent capacity, the mandated cutbacks would enter a “static reduction zone” in which the Lower Basin states and Mexico would cut 1.5 million acre-feet for the subsequent calendar year, according to the proposal.  

Only when levels dropped below 38 percent would the Upper Basin begin to incur reductions as well. The cutbacks imposed on all users would increase in a linear fashion between 38 percent capacity and 23 percent and below, the proposal stated 

“That is where we think the entire basin needs to be on deck and contributing — literally every water user across seven states and two countries needs to be part of the solution,” said John Entsminger, general manager of the Southern Nevada Water Authority.  

While the Lower Basin proposal includes Mexico in its models, Entsminger said he and his colleagues “fully recognize that our partners in Mexico are not part of this process.” Revisions to the guidelines, he stressed, are “a wholly domestic legal requirement within the United States.” 

“We fully intend to engage in a cooperative negotiation with our partners in Mexico,” Entsminger added.  

Like the 2007 interim guidelines currently under revision on the domestic front, an international agreement between the U.S. and Mexico, known as “Minute 323,” also expires in 2026.  

As for the domestic protocols, another point of contention between the two rival proposals relates to releases of water from Lake Powell to Lake Mead. The former, which serves as a storage tank for the Upper Basin, feeds water via the Glen Canyon Dam into Lake Mead, which holds water in reserve for the Lower Basin.  

The Lower Basin alternative suggested that certain amounts of water could be released from Lake Powell to Lake Mead, via the Glen Canyon Dam, for the purpose of balancing the two reservoirs. Further releases would be based on the level of their combined contents, with the amount discharged declining at lower content levels. 

The proposal, Entsminger contended, is “a realistic basin-wide proposal for how to operate under all reasonably foreseeable conditions on the Colorado River for several decades into the future.” 

JB Hamby, chair of the Colorado River Board of California, said that this alternative accomplishes four goals: It resolves structural deficit, responds to climate change, manages the entire Colorado River system and establishes storage opportunities. 

Noting that “it’s very easy to craft an alternative that doesn’t require any sacrifice,” Hamby stressed that three-quarters of the Colorado River watershed’s population resides in the Lower Basin.  

Their proposal, he contended, constitutes a “landmark agreement between our three states” that have had “a long and sometimes complicated history.”  

But Upper Basin officials envisioned Lake Powell and Lake Mead operations differently, citing a critical need to address supply-demand imbalances and align releases with real-time hydrology. Their plan calls for determining release conditions for each reservoir separately, with the amount discharged or withheld from each changing according to their individual water levels.   

While Upper Basin officials said their suggestions were based upon “actual conditions — instead of unreliable forecasts,” their Lower Basin colleagues were vocal in their opposition.  

“That proposal basically puts the entire burden of protecting the river system on the Lower Basin,” Buschatzke said. “They take no reductions under any circumstances.”  

The Arizona negotiator said that he would need to see an Upper Basin proposal in which those four states “help contribute to the protection of the river system in a way that has certainty.”  

“Our proposal would result in reductions that are going to be certain,” Buschatzke argued. “We need to see that out of the Upper Basin — not just policies and programs that might create some reductions.” 

Going forward, Buschatzke stressed a need for the Upper Basin to recognize a shared burden in protecting the system and ensuring that its joint management remains equitable.  

While officials from the two contingents have met regularly to discuss their views since the summer, Buschatzke said it became apparent that “the gap between the two proposals is pretty large” and that closing this gap would require “a lot of work.” 

That said, both sides have maintained that they are up for the challenge.  

“Arguing legal interpretations until we’re blue in the face doesn’t do anything to proactively respond to climate change,” Hamby said. “Every state, all seven, have to be equally committed to compromise and collaboration.” 

Entsminger likewise expressed some optimism, emphasizing the urgency in getting “back to the table in the spirit of shared sacrifice.”  

Interior Department acting Deputy Secretary Laura Daniel-Davis relayed similar sentiments on a press call the day before, affirming that the post-2026 process must “prioritize robust and unprecedented collaboration.”   

“We are not expecting every single issue to be smoothed out between the Upper and Lower basin tomorrow,” Daniel-Davis said.  

“But the reality is that everyone is saying the same thing,” she added. “We are all committed to a basin-wide solution and will continue to work honestly and collaboratively through any major sticking point until consensus has been reached.”