In drought-stricken West, officials weigh emergency actions
FLAGSTAFF, Ariz. — Federal officials say it may be necessary to reduce water deliveries to users of the Colorado River to prevent the closure of a large dam that supplies hydroelectric power to some 5 million customers across the western US.
Authorities hoped the melting ice would keep Lake Powell on the Arizona-Utah border afloat to ensure its dam could continue to supply power. But the snow is already melting, and higher-than-normal temperatures and prolonged drought are further shrinking the lake’s size.
The Interior Department has proposed retaining water in the lake to maintain Glen Canyon Dam’s ability to generate electricity amid what it said were the region’s driest conditions in more than 1,200 years.
“The best available science indicates that the effects of climate change will continue to negatively affect the basin,” Tanya Trujillo, Interior Undersecretary for Water and Science, wrote Friday to seven basin states.
Trujillo requested comments on the proposal to maintain 480,000 acre-feet of water in Lake Powell, enough water to supply approximately 1 million American homes. He stressed that operating the dam below 1,063 meters (3,490 feet), considered its minimum power reserve, is uncharted territory and would create even more uncertainty for the western power grid and water deliveries to states and to Mexico’s river. below.
In the Colorado River Basin, Glen Canyon Dam is the giant of energy production, supplying electricity to some 5 million customers in seven states: Arizona, Colorado, Nebraska, Nevada, New Mexico, Utah and Wyoming. As Lake Powell falls, the dam becomes less efficient. At 3,490 feet, it cannot produce power.
If levels fell below that mark, the 7,500 residents of the town on the lake, Page and the adjacent Navajo community of LeChee would not have access to clean water.
The Pacific Northwest and the Rio Grande Valley in New Mexico and Texas face similar water supply pressures.
Lake Powell dipped below 3,525 feet (1,075 meters) for the first time last month, a level that worried water managers. Federal data shows it will fall further, in the most likely scenario, before bouncing back above the level next spring.
If power production at Glen Canyon Dam ceases, customers including cities, rural electric cooperatives and tribal utilities will be forced to look for more expensive options. The loss would also complicate western grid operations, as hydropower is a relatively flexible renewable energy source that can be easily scaled up or down, experts say.
“We’re in crisis management, and human health and safety issues, including hydroelectric power production, take precedence,” said Jack Schmidt, director of the Center for Colorado River Studies at Utah State University. “Concepts like ‘Are we going to get the water back?’ they may no longer be relevant.”
The potential impacts on the lower basin states that could see their water supplies reduced (California, Nevada, and Arizona) are not yet known. But the movement of the Interior is a display of the far-reaching functions of Lake Powell and Glen Canyon Dam, and the need to change quickly to meet climate change.
Lake Powell serves as a barometer of the river’s health in the upper basin, and Lake Mead has that job in the lower basin. Both were last filled in 2000, but have been reduced to a quarter and a third of their capacity, respectively, as drought hit the region.
Water managers in the basin states (Arizona, California, Nevada, Utah, Wyoming, New Mexico and Colorado) are evaluating the proposal. The Interior Department has set April 22 as the deadline for comments.
Associated Press writers Sam Metz in Salt Lake City contributed to this report.