Take action for the Glen!

Colorado River management is at a breaking point due to years of over-consumption and climate-induced aridification. This year, the Basin is experiencing one of its driest winters on record, further revealing cracks in the system.

The Bureau of Reclamation is in the process of deciding on new rules for the future of the Colorado River. Through March 2nd, the Bureau is taking public input on the recently released Draft Environmental Impact Statement which will determine the river system’s management guidelines moving forward.

Voice your support today for including the restoration of Glen Canyon and a healthy Colorado River in the new guidelines!

For more than two decades, Colorado River users have consumed more water than the river provides, a result of over-allocation and an aridifying climate. Its two largest reservoirs, Lake Powell and Lake Mead, are hovering near historically low levels.

But there is a better path. Please take a few minutes to tell the Bureau of Reclamation that the new Colorado River Guidelines must:

1. Analyze river-level bypass of Glen Canyon Dam to ensure naturalized flows through the Grand Canyon, continue Glen Canyon’s ecological restoration, and provide maximum operational flexibility in the system. The dam has become a liability preventing water from flowing downstream. Failing to study river-level bypass needlessly limits options for the river, its users, and its ecosystems.
2. Study a “Fill Mead First” option, prioritizing water storage in Lake Mead before Powell. Today’s hydrology cannot fill either Lake Mead or Lake Powell. Given this reality, it doesn’t make sense to continue drowning the national park-caliber canyons in Glen. Analyzing different variations of a one-reservoir option would benefit the ecosystems and management of the entire Basin.  
3. Acknowledge the extensive emerging resources in Glen Canyon. In the years since Lake Powell reservoir has declined, there has been an amazing reemergence of wonders like Cathedral in the Desert and Gregory Natural Bridge, as well as vital riparian ecosystems, cultural sites, and new recreation opportunities. These resources must be given equal value to other resources across the Basin. 
4. Require curtailment plans from each state, and prohibit new non-Tribal diversions. Federal agencies must take the supply and demand crisis seriously, imploring each state to produce plans to reduce demand. These agencies should also put a moratorium on new water diversions, with the exception of Tribes with senior water rights. 

In addition to these recommendations, please take a moment to personalize your comment based on your own experiences and connection to the river. A unique comment will stand out to the Bureau and will better communicate to decision makers your care for Glen Canyon and the Colorado River.

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Learn more about the Post-2026 Draft EIS and GCI’s comment recommendations

What is the Post-2026 Draft EIS? 

The Post-2026 guidelines will guide how the Colorado River and its reservoirs will be managed in the decades ahead. Its precursor was the 2007 Interim Guidelines, which were drafted at the onset of the Colorado River’s aridification in the early 2000s. The plan was meant to hold the system over in the “interim” period of drought. Of course, we know now the drought wasn’t temporary, but was the beginning of a larger warming and drying trend in the Basin.

As climate change reduced flows on the river, government agencies implemented a myriad of additional measures to prevent Powell and Mead from dropping below minimum power pool:

• 2013 Long Term Experimental Management Plan (LTEMP) EIS
• 2019 Drought Contingency Plans (DCP), which implemented cuts in the Lower Basin
• 2022/23 Drought Response Operation Agreement, which authorized the release of water from upstream reservoirs like Flaming Gorge, Navajo, and Blue Mesa

Years in the making, many stakeholders optimistically viewed the Post-2026 process as an opportunity to address some of the systemic flaws of how the Colorado River is managed, and set a new course for a more sustainable path forward. There was a lengthy process of stakeholder meetings, pre-scoping, and scoping periods to receive public input.

GCI and dozens of other advocacy groups engaged, meeting with agency representatives, submitting extensive comments, and rallying our members to voice their support for Glen Canyon and a sustainable Colorado River. 

Simultaneously, the Colorado River Basin states publicly quarreled about who should take cuts to bring demand into balance with the river’s natural supply. As a river operated under interstate compact, the fate of this management plan always hinged on the ability for the Basin states to come to agreement.

Now, after multiple lapsed deadlines imposed by the Department of Interior, it appears there will be no state agreement. While the Draft EIS included 5 alternatives, what will likely be chosen as the “preferred” alternative will be something resembling the Basic Coordination Alternative. This alternative was designed as a fallback that could be implemented by the Department of Interior’s authority without a state-led deal, and entails some of the least aggressive water conservation of all the alternatives. 

What Happens Next?

The stark reality is that the system is already on the brink. As of February 2026, Powell reservoir is at 24% of capacity and Mead is at 34%. The Basin’s current snowpack is one of the driest in years, meaning there is very little wiggle room. The most recent projections from the Bureau of Reclamation show that, without intervention, Lake Powell is likely to drop below minimum power pool by the end of this year:  

The Basic Coordination Alternative imposes about 1.5 million acre feet (MAF) of cuts in the Lower Basin only, well below the 2-4 MAF of cuts needed to balance the system. In this scenario, it is all but guaranteed that Lake Powell reservoir will drop to minimum power pool. 

Propping Up Powell

As a temporary measure, Reclamation can reduce releases out of Glen Canyon Dam, and Upper Basin reservoirs like Flaming Gorge, Navajo, and Blue Mesa will be tapped to prop up Powell — similar to actions taken in 2022 and 2023. But this will only work for a year or two, barring a massive winter like what we saw in 2023.

If/when Powell drops near minimum power pool and upstream reservoirs have been fully tapped, the federal government will operate the dam as a “run of river” facility, meaning the amount of water released would equal the amount of water flowing in upstream. Under this scenario, water deliveries to the Lower Basin will be hamstrung by the outdated plumbing of Glen Canyon Dam, and environmental flows in the Grand Canyon (High Flow Experiments and Cool Mix Flows) would be all but impossible. 

The Elephant in the Room: Glen Canyon Dam

The primary focus of the Post-2026 process and surrounding discourse has been how much each state will reduce its consumption of Colorado River water. But upon reading the alternatives presented in the EIS documents, it becomes obvious that this process is more specifically focused on shaping policy around the outdated engineering of Glen Canyon Dam. Every alternative references the need to “protect infrastructure of Glen Canyon Dam.” The policy of the Colorado River will be bent to extremes in order to keep Lake Powell above 3,500 feet above sea level. 

Glen Canyon Dam was designed for a “goldilocks” river that is not too high or too low. In 1983, a river that was too high almost overtopped the dam and brought it down. Today we’re seeing it falter under a river that’s too low. The main way water flows through the dam is through eight hydropower penstocks. Below those penstocks, the only way to release water is through four smaller steel tubes called the River Outlet Works (ROWs). The problem is, the ROWs were only designed to be used in concert with the penstocks, not as the sole means of releasing water. In a 2024 Technical Memorandum, Reclamation acknowledged that the ROWs should never be relied upon for long term use. The Memo goes on to explain that this is because the ROWs experienced severe damage to their inner lining cavitation when used at low reservoir levels in 2023 and 1965. 

In 2023, amid growing public pressure, Reclamation hosted a webinar, revealing that they were actually looking at options to reengineer the dam to operate at lower levels. They have indicated that these studies are in the “appraisal” phase, and would likely take a decade to implement. After the reprieve of a big winter of 2023, very little has been said publicly about the re-engineering studies. 

Why Overhauling Glen Canyon Dam is Essential to the Future of the Colorado River

For years, GCI and other conservation groups have advocated for river-level bypass of Glen Canyon Dam, drilling new diversion tunnels around the concrete structure. The concept is very similar to diversion tunnels that were used during the dam’s initial construction. Bypass would allow for the Colorado River to fully flow around the dam, through the Grand Canyon and into Lake Mead. Upper Basin water, once stored in Powell, would be stored in Lake Mead with a new accounting system. In the unlikely event that Powell’s storage would once again be needed, the gates of these bypass tunnels could be closed.

When the two largest reservoirs on the system, Lake Powell and Lake Mead, were at least partially full, there was little interest in a “Fill Mead First” concept. Today, the combined contents of Lake Powell and Mead would only fill half of Lake Mead, and Glen Canyon Dam is actually impeding its original purpose. Originally built to enable the Upper Basin to fulfill its downstream delivery obligation, Glen Canyon Dam is now a bottleneck in the system, preventing downstream flow. Now that both reservoirs are hovering near critical levels with the hydrology expected to get worse, the bypass concept has gained broader support. 

Experts have pointed out that bypassing Glen Canyon dam would unlock 5.6 MAF of water locked up behind the dam. And, fearing the impending water delivery crisis to downstream users, the Lower Basin states of California, Nevada, and Arizona wrote a letter to Reclamation in February of 2025 specifically asking for dam modifications to be incorporated into the Post-2026 EIS. With concern for the fragile ecosystem of the Grand Canyon below the dam, leading scientists have suggested bypass may be a key solution for the drying river, stating: “Such an action would restore a natural stream flow and sediment regime to the Grand Canyon and might benefit some pre-dam elements of the Colorado River ecosystem.” Under a bypass scenario, the restoration of Glen’s national park-caliber ecosystem, cultural resources, and recreation opportunities could continue. 

Despite the growing calls among stakeholders, concepts submitted by GCI and partner organizations to prioritize water storage in Lake Mead and re-engineer Glen Canyon Dam with river level bypass tunnels were not analyzed in this EIS. The stated reason for this is that these concepts “would require such extensive statutory modifications or amendments that it is unlikely to be acceptable among stakeholders and would be inconsistent with federal law.”

This argument is deeply flawed. While bypassing Glen Canyon Dam and consolidating in storage in Mead would be a new approach, it only becomes more practical as the system declines. Consider the following:

• Fill Mead First, which would entail storing Upper Basin water in Lake Mead “is not precluded by any Federal or State statutes,” according to a legal analysis published in The Water Report. This analysis states that “FMF may well become a piece of the answer to how we bring basin water uses into line with reliable basin water supplies. The questions about its feasibility are not essentially legal but hydrologic and political.”
• FMF would essentially be a type of inter-basin water storage exchange, similar to concepts analyzed in other alternatives. 
• Major stakeholders explicitly asked the Bureau of Reclamation to analyze Glen Canyon Dam modifications in a letter from Lower Basin states last year. 
• Reclamation itself is currently analyzing modifications to Glen Canyon Dam so that it can operate at low levels in a process separate from this EIS. They wouldn’t be doing this if it were unnecessary or inconsistent with the law.

Your Comments Matter

The guidelines that will emerge from this process will be short-term, and do little to address the systemic flaws of the system. Reclamation’s approach has ignored the serious engineering flaws at Glen Canyon Dam, instead focusing all efforts on propping up the reservoir at great sacrifice to water users and the environment basin-wide. Whatever is decided in this process, it will not be a long term plan.

And yet, the Post-2026 EIS is not the end of adapting policy to the modern Colorado River—it is just the beginning. There will be critical decisions made in the months and years ahead, and it is essential that we all voice our support for Glen Canyon and a free-flowing Colorado River!