Lake Powell is nearing critically low elevation levels, with water at 3,524.3 feet above sea level as of Monday, according to the U.S. Bureau of Reclamation tracker.
Minimum, or "dead," power pool — the elevation at which hydropower can no longer be produced — starts at 3,490 feet, and Lake Powell's elevation is about 34 feet above that threshold, Peter Soeth, public affairs lead at the Bureau of Reclamation, said.
Lake Powell currently has about 5.52 million acre-feet in live storage and has lost about 4,800 acre-feet per day since June 1, Jack Schmidt, director of the Center for Colorado River Studies at Utah State University, said; since the early 1960s the reservoir has never been lower than 5.26 million acre-feet in live storage. Schmidt said reservoir operations can get "very complicated" once elevation drops below 3,500 feet and live storage drops below 4.3 million acre-feet and that the Bureau of Reclamation would "be seriously concerned" at that point.
The reservoir could reach a dead pool when its elevation drops to 3,370 feet; in a dead pool about 240 feet of water would be trapped at the bottom of the canyon and unable to flow to millions of people in Arizona, California and Nevada.
Full pool elevation at Lake Powell is 3,700 feet, according to the Lake Powell Water Database.
The Colorado River Basin is experiencing the impacts from the lowest snowpack on record, Soeth said.
Above-average precipitation is favored across much of the West, according to the National Oceanic and Atmospheric Administration's Climate Prediction Center, and monsoon season and an intensifying El Niño are underway and could bring more chances for rain; experts said any additional precipitation will not offset long-term factors driving shortages such as prolonged drought and historically low seasonal snowpack.
In May, the Colorado River Basin Forecast Center projected that Lake Powell could drop to a new record-low level by July based on expected inflow rates between April and July, and Schmidt said, "If you do the simple math, it would suggest that Lake Powell will set a record for its lowest point in about a month and a half."
Lake Mead was measuring 1,042.8 feet above sea level, just over 2 feet above its record-low level; Bureau of Reclamation data shows Lake Mead dropped about 5 feet in June and could approach the record of 1,041 feet set in July 2022 by the end of the month.
Experts said the basin is severely over-allocated and water rights were established during a period when water levels were "unusually high," Erica Fleishman, director of the Oregon Climate Change Research Institute, said; Dave White, director of the Global Institute of Sustainability and Innovation at Arizona State University, said lower basin states have submitted an allocation plan but there is not yet a consensus among all of the states. "The Department and Reclamation remain committed to reducing the collective risk of both Lake Powell and Lake Mead falling below critical elevations to protect critical infrastructure so that it can continue to function as authorized to meet the water and hydropower needs of the basin," Soeth said. The Bureau of Reclamation is set to release another update to the projections this week.