FLAGSTAFF, Ariz. (AP) — Federal officials say cuts in water deliveries to users of the Colorado River may be necessary to prevent the closure of a huge dam that provides hydroelectricity to some 5 million customers in the western United States.
Officials hoped the melting snow would support Lake Powell on the Arizona-Utah border to ensure its dam could continue to provide power. But the snow is already melting, and warmer-than-normal temperatures and prolonged drought are shrinking the lake further.
The Department of the Interior has proposed retaining water in the lake to maintain Glen Canyon Dam’s ability to generate electricity in what it called the driest conditions in the region for more than 1 200 years.
“The best science available indicates that the effects of climate change will continue to negatively impact the basin,” Tanya Trujillo, assistant secretary of the interior for water and science, wrote seven states in the basin on Friday.
Trujillo asked for comment on the proposal to conserve 480,000 acre-feet of water in Lake Powell — enough water to serve about 1 million American homes. She pointed out that operating the dam below 3,490 feet (1,063 meters), considered its minimum power pool, is uncharted territory and would lead to even more uncertainty for the western power grid and power deliveries. water to the States and Mexico downstream.
In the Colorado River Basin, Glen Canyon Dam is the mammoth of power generation, providing power to approximately 5 million customers in seven states – Arizona, Colorado, Nebraska, Nevada, New Mexico, Utah and Wyoming. As Lake Powell falls, the dam becomes less effective. At 3,490 feet, it cannot generate power.
If levels were to fall below that mark, the 7,500 residents of the lakeside town of Page and the adjacent Navajo community of LeChee would not have access to clean water.
the Pacific Northwestand the Rio Grande Valley in New Mexico and Texas face similar water supply pressures.
Lake Powell fell below 3,525 feet (1,075 meters) for the first time last month, a level that has water managers worried. Federal data shows that it will dip further, in the most likely scenario, before bouncing back above next spring’s level.
If power generation ceases at the Glen Canyon Dam, customers that include cities, rural electric cooperatives and tribal utilities would be forced to seek more expensive options. The loss would also complicate Western Network operations since hydroelectricity is a relatively flexible renewable energy source that can be scaled up or down easily, experts say.
“We are in crisis management, and human health and safety issues, including hydroelectric generation, are a priority,” said Jack Schmidt, director of the Center for Colorado River Studies at the University of Washington. State of Utah. “Concepts like ‘Are we going to get our water back’ may not even be relevant anymore.”
The potential impacts on states in the lower basin that could see their water supply reduced – California, Nevada and Arizona – are not yet known. But the interior move is a demonstration of the extended functions of Lake Powell and the Glen Canyon Dam, and the need to pivot quickly to deal with climate change.
Lake Powell serves as a barometer for the health of the river in the upper basin, and Lake Mead has that job in the lower basin. Both were last full in 2000 but dwindled to a quarter and a third of their capacity, respectively, as drought tightened its grip on the region.
Water managers in basin states — Arizona, California, Nevada, Utah, Wyoming, New Mexico and Colorado — are evaluating the proposal. The Home Office has set April 22 as the deadline for comments.
Associated Press writer Sam Metz in Salt Lake City contributed to this report.