As the Colorado River and its massive reservoirs shrink due to overuse and climate change, officials face a decision that pits environmental conservation against taxpayer-paid electricity costs.
To combat predators of the humpback, an endangered fish native to the river, Glen Canyon Dam in northern Arizona will need to do what is known as a “cold-mix flush,” where cold water is released from deep within its reservoir to cool the river below. But there are no hydroelectric turbines in the cold deep section, so a significant amount of power generation will be lost.
The proposal comes after Worst snow It is a record for the Colorado River Basin, which depends on farmers, industries, wildlife and more than 40 million people in seven US states, tribal nations and Mexico. It also comes with the failure of those countries to reach Long term agreement On how the river’s dwindling resources will be shared after this year, when the guidelines expire.
“There is a limited water supply,” said John Berggren, regional policy director for the environmental nonprofit Western Resource Advocates. “It’s declining even more. Still, a lot of tough decisions have to be made.”
The utilities that buy this hydropower say that releasing cold water would be expensive because they would have to spend millions to buy replacement power and would increase financial hardship for customers. But proponents say that without cold releases, the warmer waters expected downstream this summer will allow non-native predatory fish to reproduce, further threatening the environment. The humpback chubwill destroy world famous Trout fishing close.
The Bureau of Reclamation, which is expected to announce a decision in the next two weeks, said in a statement that it is considering several factors including the environmental health of the river and the dam’s hydroelectric production. The Interior Ministry, which oversees the office, declined to comment. If the cold water is approved for release, it would likely occur from June to October through jet tubes, bypassing turbines near the warmer surface.
Lake Powell, one of two massive reservoirs on the Colorado River, is only 23% full after decades of overuse and evaporation of water as average temperatures rise due to climate change. A record low in flow is expected this summer. With such a low reservoir, warm water near the surface is sucked in by the generators and sent downstream.
Smallmouth bass, introduced to Lake Powell in the 1980s for sport fishing, live on this warm surface, and are also sucked by hydroelectric generators into the river below. That’s a problem for humpbacks and other federally protected fish in the Grand Canyon, which runs 278 miles (447 kilometers) south on the river world-famous for its geological formations. A Recent study It shows that about half of the bass survive the generators. If the river below is warm enough, they spawn.
Smallmouth bass already feed on humpbacks in the upper section of the river, with agencies spending millions of dollars annually to control the intruders. Local fish were safer below Glen Canyon Dam because it blocks the path to the Grand Canyon, but that may not be true for long.
Water temperatures below the dam are expected to break records set in 2022, when smallmouth bass temperatures were It was first found there. Officials expect water temperatures to consistently exceed 60 degrees Fahrenheit (15.5 degrees Celsius) by mid-June due to the withdrawal of warm water from Lake Powell. Any higher than that, and non-native predatory fish passing through the dam can reproduce.
Officials say cold water releases from Lake Powell in 2024 and 2025 succeeded in preventing spawning.
It’s critical to consider the cost of not doing this great combination, Heather Whitlow, a field supervisor with the U.S. Fish and Wildlife Service, said during a recent meeting on managing the problem. “We are certainly giving up the future for any kind of recovery for the humpbacks and all the other parts of the system that depend on cold water temperatures.”
With no long-term solution to prevent predators from passing through the dam, blocking the cold water would force officials to rely solely on manually removing them downstream.
Utilities that rely on hydropower from federal generators are concerned.
If the cold water release is approved, it could mean bypassing about half of the generation at Glen Canyon Dam, forcing utilities to buy power elsewhere that would likely be more expensive, according to the Utah utility group HyperLight. & power.
“We continue to hear comments that we should continue the Cool Mix program because the cost of not doing so would be greater,” the Colorado River Power Distributors Association, which represents about 155 customers who buy federal hydropower generated from the river and opposes the releases, said this month in a letter to Interior Secretary Doug Burgum. “We would like to understand what treatment is always going to cost more than $20 to $30 (million) a year.”
The association said the releases are not a sustainable solution to prevent smallmouth bass from multiplying and threatening an important fund used to operate, maintain and invest in hydroelectric and transmission facilities.
During cold water releases in 2024, nearly 900,000 acre-feet of water would bypass generators, costing $19 million in replacement energy costs, according to the Bureau of Reclamation. It’s unclear how much water will bypass the generators this year, though the cost of replacing them is expected to be about $25 million — roughly the total cost to hydropower users from the previous two years.
The continuing loss of hydroelectric power due to the decline of Lake Powell has presented challenges for Heber Light & Energy as the population grows, said Emily Brandt, the utility’s director of energy resources. The general decline has led to higher interest rates in the past five years.
Anne Moulton, who lives in Heber City, looked at her home’s electricity bill from Heber Light & The strength rises steadily. Her bill in April was $125.98, up from $103.24 and $86.14 for the same month in the previous two years. She said this affects her budget.
Other customers are struggling to pay. So far this year, utilities have seen a jump in late payments over the past two years, from 10% to 12%.
The facility supports fish welfare, “but this particular experiment seems unnecessary,” Brandt said.
“We were already seeing a decline in generation due to drought, and now we are seeing an even greater decline in generation due to this environmental experiment,” Brandt said.
Dave Foster still remembers 2022 Trout death In Marble Canyon, a remote stretch of river located between the dam and the beginning of the Grand Canyon. Foster, who has been working on or around this section of the river since he was 13, said warmer waters have killed nearly half of the rainbow trout on which the world-famous fishery depends.
He and other guides are still recovering from death, he added, because “the population simply has not rebounded.” But cold water releases in recent years have more than offset the negative impacts, and more of them will continue this year through the fall and winter.
Foster warned customers who book trips after mid-June that he may cancel them if the water gets too warm, which could stress the fish. Without cold-water release this year, “that’s it for trout fishing,” he said. “There’s no mystery about it. It will destroy him.”
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