A new report compiled by the U.S. Geological Survey and the Bureau of Reclamation provides updated information on Lake Powell’s storage capacity.
The report confirms Lake Powell has lost 6.79 percent capacity since 1963, when the diversion tunnels of Glen Canyon Dam closed and the reservoir began to fill. The loss is mainly due to sediment transported by the Colorado and San Juan rivers settling on the reservoir bottom.
This most recent survey shows the total storage capacity is 25,160,000 acre-feet—a decrease of 1,833,000 acre-feet, or 6.79 percent of storage capacity, from 1963 to 2018. The average annual loss in storage capacity was approximately 33,270 acre-feet per year between 1963 and 2018.
