- Upper Basin states are seeking long-term credit for water they voluntarily conserve and send to major reservoirs.
- Lake Powell was only 22 percent full on September 8, 2026.
- Federal modeling places Powell in a low-elevation protection range for water year 2027.
- Current modeling projects drought-response releases from Flaming Gorge could total 1 million acre-feet by April 2027.
- The Upper Basin says credited water should remain stored in reservoirs without changing normal operations.
Friday, September 18, 2026 –– The four Upper Colorado River Basin states are working on a plan that could change what happens to water they voluntarily conserve and send into the Colorado River system.
Colorado, New Mexico, Utah and Wyoming want those water contributions to be measured, credited and stored in Lake Powell and other major Upper Basin reservoirs.
The request comes as Lake Powell remains exceptionally low and federal water managers prepare for another difficult operating year.
In a September 11 letter to the U.S. Department of the Interior
, the Upper Colorado River Commission said the states are working with the Bureau of Reclamation on agreements covering voluntary water-conservation projects and how that conserved water will be handled once it reaches federal reservoirs.
The letter was presented in connection with the Upper Colorado River Commission’s 318th Special Meeting on September 14.
At that meeting, federal officials also presented new reservoir and river forecasts showing why the issue has become important. Lake Powell was at 22 percent of its live storage capacity as of September 8. Flaming Gorge Reservoir was at 70 percent, Blue Mesa Reservoir at 20 percent and Navajo Reservoir at 48 percent.
$100 Million for Voluntary Water Contributions.
At the center of the discussion is the Upper Basin Conservation and Contribution Program.
The Department of the Interior is finalizing a $100 million grant for the program. According to the Upper Colorado River Commission, the money would expand state-led efforts to voluntarily contribute water to four major federal reservoir facilities: Lake Powell, Flaming Gorge Reservoir, the Aspinall Unit in Colorado and Navajo Reservoir.
The Commission and Bureau of Reclamation are now developing an agreement spelling out which projects can receive that money.
To qualify, a project would have to produce a measurable amount of water that would not otherwise have been available for storage in one of those reservoirs.
The commission wants that agreement completed this fall so projects can be selected and begin contributing additional water in 2027.
The Bigger Question: What Happens to the Water?
Another agreement under development deals with a more complicated issue.
Once an Upper Basin state conserves water and sends it into the reservoir system, how should the Commission count and treat that water?
The states want those contributions officially credited.
They also want credited water stored in what the Commission calls “operationally neutral pools” in Lake Powell and upstream reservoirs.
In simple terms, the states do not want a voluntary contribution to automatically cause other reservoir operations to change in a way that effectively cancels the benefit of storing that water.
The Commission told Interior that this treatment would be important to continued participation by the four states.
“Without these elements, participation in an Upper Basin Program may be significantly limited,” the September 11 letter states.
The Commission said the Upper Basin states intend to discuss both agreements with Lower Basin representatives and seek their input “at the appropriate time.”
A System for Measuring Conserved Water.
The Upper Basin is not starting from scratch on tracking these contributions.
The Commission said accounting and verification would build on methods developed under a December 2024 agreement between the Upper Colorado River Commission and Bureau of Reclamation.
Those methods were used to calculate water contributed by the Upper Basin states to the federal reservoirs and were later verified by Reclamation.
The new agreements would build on that system.
Lake Powell Is Already in a Protection Range.
The timing is significant because Lake Powell is entering water year 2027 at a low level.
The Bureau of Reclamation’s August 2026 modeling projected Powell at elevation 3,515.89 feet on October 1, putting the reservoir within what federal operating rules call the “Low Elevation Infrastructure Protection Range.”
Under the 2027-2028 operating guidelines, federal managers generally try to keep Powell at or above elevation 3,510 feet when the reservoir is within this range.
The guidelines allow adjustments to releases from Lake Powell and, under certain circumstances, additional releases from upstream Colorado River Storage Project reservoirs. If projections show Powell falling below 3,500 feet, additional consultation is required.
For water year 2027, the final Lake Powell release has not yet been determined.
The August modeling calls for a release somewhere between 6 million and 7 million acre-feet, with the decision expected in April. The modeling showed that a 7 million acre-foot release could cause Powell to fall below elevation 3,510 feet.
An acre-foot is about 326,000 gallons, roughly enough water to cover one acre of land one foot deep.
Flaming Gorge Is Already Sending Water Downstream.
The presentation also shows how much water may be involved in protecting Lake Powell.
Under the Upper Basin Drought Response Operations Agreement, upstream federal reservoirs can release water to help protect critical elevations at Lake Powell.
The Bureau of Reclamation reported releasing 308,000 acre-feet of drought-response water through July 2026. Its August modeling projected those releases could reach 1 million acre-feet by April 2027. The presentation identifies Flaming Gorge Reservoir as the source of those modeled releases.
The federal operating guidelines also point to earlier actions involving upstream reservoirs. Those included a planned 500,000 acre-foot release paired with a 480,000 acre-foot reduction in Lake Powell releases, and another planned upstream release of 660,000 to 1 million acre-feet paired with a 1.48 million acre-foot reduction in Powell releases.
A Very Dry 2026.
The reservoir situation follows an unusually poor runoff season.
Observed April through July 2026 unregulated inflow into Lake Powell totaled about 1.14 million acre-feet, just 18 percent of the 1991-2020 average.
Other Upper Basin reservoirs also received well-below-average inflows during that period. Flaming Gorge received 34 percent of average, Blue Mesa 24 percent and Navajo Reservoir 22 percent.
Conditions are projected to improve in 2027 under the September most-probable forecast, although inflows would still remain below average.
For April through July 2027, Lake Powell’s forecast unregulated inflow is about 5.05 million acre-feet, or 79 percent of average. The full water-year forecast is approximately 7.32 million acre-feet, or 76 percent of average.
The Next Steps.
The Upper Colorado River Commission’s September letter focuses on two agreements.
One would establish the rules for distributing the $100 million in federal funding and selecting voluntary conservation projects.
The other would address the broader Upper Basin program, including how contributed water is counted, credited, and stored.
The Commission told the Department of the Interior that it wants the agreements moved forward quickly enough for the program to begin operating in 2027.
For the Upper Basin states, the issue is not simply whether water can be conserved.
Their September 11 letter makes clear that they are also seeking rules governing what happens to that water after it reaches Lake Powell, Flaming Gorge, Blue Mesa or Navajo Reservoir, and whether those voluntary contributions can remain identifiable in storage for the benefit of the reservoir system.
