Water levels are still so high in some parts of TVA's water system from recent precipitation that the utility giant is spilling water.
At Fontana Lake, TVA plans to release 7,900 cubic feet of water, or about 59,000 gallons, using sluice gates and a spillway tube.
Authorities will be releasing the water for at least a week to lower lake levels and recover flood storage space at Fontana.
Some parts of East Tennessee have seen more than 6 inches of rain in the last week or so.
Fontana Dam, on the Little Tennessee River in western North Carolina, is the highest dam east of the Rockies, according to TVA.
It was built during World War II.