Drought puts Blue Mesa in crosshairs again

(Editor's note: This article has been updated to reflect a correction. Releases are being considered in 2026, not 2025.)

After weeks of hot, dry and windy weather across western Colorado, Gunnison County Commissioners received a water-issues update on Tuesday that was filled with “sobering” news. In addition to details about Gunnison County’s worsening drought conditions, commissioners heard from representatives of the Colorado Water Conservation Board (CWCB) that the U.S. Bureau of Reclamation is once again considering emergency releases from Blue Mesa Reservoir in 2026 to bolster falling water levels in Lake Powell.

According to drought.gov, approximately 50% of Gunnison County is in “extreme” drought, compared to just 5% one month ago. Conditions in most of the remainder of the county are rated as “severe.” Precipitation for most of the county has been between 25% and 50% of normal for the past 30 days, with little immediate relief in sight.

Problems at Lake Powell

CWCB representative Amy Ostdiek told commissioners she believes emergency releases will come from elsewhere in the Upper Basin this year, but couldn’t rule out the possibility that Blue Mesa would be included.

“We don't have any assurances about that, and there's no hard and fast formula or any kind of calculation that's used to determine which reservoir is used,” she said. “But we do know that Reclamation and all the upper division states would look at how much water is uncontracted, that is, how much water is available in each reservoir. Flaming Gorge happens to have a lot more.” 

If current conditions persist, Lake Powell is projected to fall below the critical elevation of 3,525 feet above sea level in the spring of 2026. This would be the second time that has occurred since the reservoir filled in 1980. The other time happened in 2021, precipitating emergency releases from Blue Mesa Reservoir and Flaming Gorge and Navajo reservoirs totaling 180,000 acre-feet. An acre-foot is the volume of water that would cover one acre a foot deep.

As of Aug. 10, Blue Mesa was 61% full and is projected to end the year at 51% of its storage capacity — without any additional releases. Taylor Reservoir is forecasted to be at 65% of average capacity at the end of 2025.

The threshold of 3,525 feet at Lake Powell was agreed to in the Upper Basin Drought Response Operations Agreement as the trigger point for possible releases. The purpose is to prevent Lake Powell from dropping below 3,490 feet, known as “dead pool” — the point at which the Glen Canyon Dam can no longer generate electricity. Up to 5 million people across six western states depend on hydroelectric power from the dam.

Emergency releases in 2021 were controversial. Critics argued that federal authorities did not properly consult with Upper Basin water users prior to the decision and failed to account for impacts to local economies and communities. Further, many objected on the grounds that water managers had no way of measuring whether the extra water in fact reached Lake Powell.

“We need to make sure that as we move to the future, that that isn't happening the same way,” CWCB Commissioner Becky Mitchell told county commissioners. “There needs to be a more thoughtful effort taken by the federal government before they do things like that, and also that appropriate actions are taken in the Lower Basin before they look to the already shorted Upper Basin.”

To complicate matters, the 2007 agreement between upper and lower Colorado River Basin states that guides decision-making in the event of shortages is set to expire in 2026. Negotiations are underway to overhaul how all the reservoirs in the Colorado River system are managed. The Colorado River Compact was agreed to in 1922 and set the amounts of water that upper basin states — Wyoming, Utah, Colorado and New Mexico — and lower basin states — California, Nevada and Arizona — are entitled to receive.

That agreement has been managed on a “demand-driven” model, Mitchell told commissioners. In other words, releases to lower basin states have exceeded their compact allotments based on increasing demand for water. That has occurred even when the supply of water in any given year is limited by lack of precipitation.

In response to prolonged drought across the West that has lasted more than two decades, Upper Basin negotiators are pressing for a “supply-driven” plan for determining how much water is released from Lake Powell and Lake Mead each year — based on what’s available, not just what’s needed downstream.

Algae in bloom

In a related presentation, commissioners heard from U.S. Geological Survey scientist Katie Walton-Day about ongoing research to understand and better predict blooms of toxic algae in Blue Mesa Reservoir. Technically, this doesn’t involve algae at all, but photosynthesizing organisms called cyanobacteria. Some types of these bacteria release toxins when they die. Nevertheless, researchers refer to spikes as harmful algal blooms (HAB).

Portions of Blue Mesa Reservoir were placed under an HAB advisory this week (see related story on A3).

While studies are ongoing and all findings are inconclusive at this point, initial evidence suggests that water levels and temperature may be key drivers of the frequency and severity of toxic blooms. Researchers aim to develop early warning systems to adequately inform reservoir users about potential hazards.

However, water managers hope to use the information to help inform BOR decision-making about water releases from Blue Mesa. Lower water levels in late summer or early fall, when releases would likely take place, may contribute directly to algal blooms and pose health threats that should be taken into account, Mitchell said.

“We need to keep elevating what can be done, what's possible, where it's not possible,” Mitchell said. “Talk about the facts, what's happening on the ground in the Upper Basin and also what's happening on the ground in the Lower Basin that needs to change.”

(Alan Wartes can be contacted at 970.641.1414 or publisher@gunnisontimes.com.)