Colorado River plan shifts water to keep Lake Powell’s turbines running
Water officials in the U.S. Southwest are planning to surge water into drought-depleted Lake Powell by releasing more water from upstream Flaming Gorge Reservoir, with the goal of keeping electricity generation operating at Glen Canyon Dam. The approach follows the driest winter on record, when managers began moving to raise Lake Powell’s level to maintain hydropower output that supplies power to households and utilities across much of the region.
The Colorado and Green River flows would normally be seen as a seasonal boost in a parched landscape, but officials describe the situation as the opposite: managers are trying to compensate for depleted storage rather than take advantage of abundant runoff. They want to raise the badly depleted Lake Powell by eventually letting out as much as a third of the water in Flaming Gorge Reservoir, a release plan that would exceed a surge in 2022 meant to keep power flowing.
For some communities near the Green River, the release plan has a direct effect on recreation and access. At Flaming Gorge in southwestern Wyoming, Buckboard Marina owners Tony and Jen Valdez said they expect water levels to decline by about 10 feet (3 meters) by late summer because of the releases, which they said could leave boats launched from farther from shore.
Jen Valdez said, “Of course we’re concerned,” adding, “And it will probably get to a point where we’ll need to be more concerned.” She said the lowering would likely continue beyond the immediate release period, describing how the magnitude of the drawdown could affect the marina even if managers see the measure as temporary.
Federal officials said the drastic release measures are necessary to keep Lake Powell’s waterline high enough to run Glen Canyon Dam’s hydropower turbines without air getting into the system and causing damage. The operation depends on keeping reservoir levels above thresholds tied to the dam’s electricity generators and water intake structures.
The plan also creates downstream tradeoffs that affect other parts of the basin. The U.S. Bureau of Reclamation water managers plan to keep more water than usual from flowing out of Lake Powell on the Arizona-Utah line, and the article said Lake Mead near Las Vegas is on track to resemble lows seen four years ago, when boats and even human remains were exposed.
Hydropower is central to the region’s electricity supply but not the only source. Some 155 customers receive hydropower electricity from Glen Canyon Dam and other federal generators, and none relies on hydropower alone, according to the reporting. The Western Area Power Administration has contractual obligations to provide a certain amount of electricity to its customers, and officials said a loss of hydropower could force Western Area Power Administration to seek alternative supplies that are likely more expensive and not renewable.
Leslie James, executive director of the nonprofit Colorado River Energy Distributors Association, said that if Glen Canyon hydropower dropped to zero or a low amount, it could change impacts on what customers are charged, adding that she had not seen such a scenario in her 48 years of helping electricity customers in Arizona, Colorado, Nevada, New Mexico, Utah and Wyoming. The article also cited Emily Brandt, the energy resource manager for Heber Light & Power southeast of Salt Lake City, saying replacing hydropower with market purchases has required rate increases for the past five years, with the latest increase reaching 13%.
Environmental costs are also part of the calculus. The reporting said increasing drought, evaporation and water demand—especially for alfalfa irrigation in the cattle industry—have reduced Lake Powell to 3,526 feet (1,075 meters) above sea level, about 23% of full capacity. Managers said the reservoir cannot fall below 3,490 feet (1,200 meters), which is tied to the water intakes for Glen Canyon Dam’s electricity generators.
The article said the situation has not previously occurred since the 710-foot (220-meter) dam was completed in 1963 and Lake Powell filled to full capacity in 1980. In 2022, the Bureau of Reclamation released an unprecedented 500,000 acre-feet (617 million cubic meters) of water from Flaming Gorge to raise Lake Powell, and the latest releases described in the reporting could eventually total double that amount.
It also said holding back 1.5 million acre-feet (1.85 billion cubic meters) in Lake Powell will contribute to Hoover Dam producing 40% less electricity and to Lake Mead downstream reaching even lower levels. The reporting added another potential ecological downside: warm water from the Lake Powell surface could encourage the spread of smallmouth bass, an invasive fish that competes with the threatened humpback chub downstream from Glen Canyon Dam.
The story said groups including the Grand Canyon Trust urged water managers to mix in deeper, cooler water to keep the Grand Canyon inhospitable to smallmouth bass. Looking ahead, the strongest releases from Flaming Gorge in the days and weeks ahead will be calibrated to help native fish in the Green River, a Colorado River tributary.
The reporting said Flaming Gorge would dip from 83% full to an estimated 59% full after the releases, and that the 2022 releases were followed by a wet winter that briefly reduced water worries. Tony Valdez said, “We kind of got saved by Mother Nature,” and added, “Hopefully we can expand into doing some other things,” adding, “Because it’s going to come back eventually.”