River Stakeholders
Wyoming River Water Use Highlights:
Wyoming Colorado River Water Use:
Water Year 2025
Wyoming’s water year 2025 was hot and dry, especially during the irrigation season. Although snowpack was average, runoff was much less than average resulting in reduced streamflow, reservoir storage, and irrigation. This was partly due to low soil moisture conditions but also to the exceptionally dry summer. Some areas received no measurable precipitation for the entire summer. In most parts of the basin, the April-July rainfall was below the 15th percentile. Farmers and ranchers struggled, with Wyoming’s State Engineer’s Office regulating off at least 164,000 acres of irrigation—this regulation produces involuntary and uncompensated reductions. For comparison, 176,000 acres were regulated off in 2021, one of the driest years in the last century. During September, the Green River gage near La Barge, Wyoming recorded the lowest flows in its 50-year record.
Predictably, hot and dry conditions in Wyoming’s headwaters and elsewhere in the basin produced negative impacts to Lake Powell. 2025 Lake Powell inflows were about 4.7 million acre-feet while releases were 7.48 million acre-feet, resulting in a significant storage reduction. The reduced Lake Powell storage levels triggered planning to begin under the Drought Response Operations Agreement (DROA) and will continue through April 2026. Although DROA actions may only require retiming of monthly Lake Powell releases, they may also require releases from upstream Initial Units, such as Flaming Gorge. The magnitude of any 2026 DROA releases will depend on next winter’s snowpack and resulting streamflow, as well as possible reductions in Lake Powell releases under its current operating rules. Wyoming will remain fully involved in that process recognizing Flaming Gorge’s importance to Wyoming’s local economy as well as its purpose of providing a critical buffer for dry years.
In response to the Colorado River’s historically dry conditions, Wyoming continues to act proactively and remains committed to helping develop collaborative solutions. Wyoming has commenced and continues to make progress on multiple studies, many which are designed to improve our ability to measure water supply and water use and continue to build upon the commitments we’ve fulfilled under the 2019 Demand Management Storage Agreement. Sharing federal funding with the other Upper Basin States, Wyoming has installed five eddy covariance towers to help ground truth remote sensing consumptive use estimates. We continue to support field studies with the University of Wyoming, Trout Unlimited, and The Nature Conservancy to better quantify conservation and understand the impacts of fallowing and irrigation timing. Wyoming continues to coordinate with the USGS to install 30 new stream gages, and has begun studies on reservoir evaporation and airborne snowpack observation with runoff forecasting. Wyoming has also initiated a program to improve diversion measurement data, as well as assist water users, by funding a portion of the costs for new measurement devices on thousands of diversions.
With funding from Wyoming’s legislature, Wyoming continues to enhance its water management tools. We are developing a Wyoming-specific river model similar to that used by Reclamation; constructing a data-sharing site for stream flows, diversions, and reservoir level data (GreenRiverBasin.org); conducting transit loss studies on Green River and New Fork River upstream of Flaming Gorge Reservoir; and studying impacts of water availability on consumptive use. Wyoming has also spent considerable resources improving our inventory of water diversions regarding conditions and locations.
Wyoming is also actively pursuing tools to effectively engage in voluntary water conservation. Wyoming and its Congressional delegation have supported reauthorization of the System Conservation Pilot Program. That program would provide for temporary, voluntary, and compensated water conservation in the Upper Basin. Additionally, Wyoming and the other Upper Basin States have developed and implemented demonstration projects under the provisional accounting memorandum of understanding they entered with the Bureau of Reclamation in late 2024. The contemplated accounting is necessary to quantify and receive necessary credit for Upper Basin water conservation. Finally, Wyoming is pursuing legislative authorization for a pilot voluntary water conservation program. The potential program is intended to build on all of the substantial work Wyoming has previously performed regarding voluntary water conservation, and aims to provide a program which can effectively work for Wyoming water users under Wyoming’s unique laws and circumstances as well as effectively contribute to a broader Upper Basin conservation program. Wyoming’s Legislature approved the topic for study in early 2025 which may lead to the consideration of authorizing legislation in the 2026 legislative session. To advance the effort, between May and September of 2025, the Wyoming State Engineer met with the interim legislative committee twice, held multiple public meetings with the Wyoming Colorado River Advisory Committee, and conducted three public meetings in the Green and Little Snake River basins. While Wyoming remains fully committed to collaborative solutions, any solution must adequately assess and mitigate impacts to Wyoming’s water users, its natural resources, and its affected communities.