Lake Powell’s overall capacity is declining, report shows
Lake Powell, the second largest man-made reservoir in the US, has lost nearly 7% of its storage capacity since 1963, when the Glen Canyon Dam was built, according to a new report.
In addition to water loss due to severe multi-year drought, a U.S. Geological Survey and Bureau of Reclamation report found that Lake Powell was facing an average annual loss of storage capacity of about 33,270 acre-feet, or 11 billion gallons , every year between 1963 and 2018.
That’s enough water to fill the reflection pool on the National Mall about 1,600 times.
The reservoir’s capacity is declining because of sediments flowing in from the Colorado and San Juan rivers, according to the report. These sediments settle at the bottom of the reservoir and reduce the amount of water that can be held in the reservoir.
As of Monday, Lake Powell was about 25% full, according to data from the Bureau of Reclamation.
It is bad news for an area that is already suffering from a lack of water and severe wildfires due to the drought. National Oceanic and Atmospheric Administration drought experts said last week that those conditions are expected to continue — if not worsen — in the coming months.
Lake Powell is an important reservoir in the Colorado River Basin. Both Lake Powell and nearby Lake Mead, the nation’s largest reservoir, have drained at an alarming rate. In August, the federal government declared a water shortage on the Colorado River for the first time after Lake Mead’s water level dropped to unprecedented levels, triggering mandatory water consumption cuts for Western states. – right that started in January.
And last week, Lake Powell dipped below the critical threshold of 3,525 feet above sea level, raising further concerns about the water supply and hydroelectric power generation that millions of people in the West rely on for electricity
The importance of the dwindling water supply throughout Colorado cannot be overstated.
The system provides water for more than 40 million people who live in seven Western states and Mexico. Lakes Powell and Mead provide vital supplies of drinking water and irrigation to many across the region, including rural farms, ranches and indigenous communities.
“It is extremely important that we have the best available scientific information such as this report to provide a clear understanding of Lake Powell’s water availability as we plan for the future future,” Tanya Trujillo, assistant secretary for water and science with the U.S. Department of the Interior. , said in a statement. “The Colorado River system is facing a number of challenges, including the effects of a 22-year drought and greater effects of climate change.”