The Tennessee Valley Authority continues to repair tornado damage to its power transmission lines from Friday's storms, spokeswoman Myra Ireland said.
The most damage is in Harrison and Davis Mill areas in Hamilton County and into Bradley County, Ireland said.
A line near Murphy, N.C., and two lines west of Huntsville, Ala., were damaged as well, she said.
On Sunday evening, nine lines still were out of service, down from 16, Ireland said.
"A total of 20 structures are damaged - from minor damage to tangled [steel and cables] on the ground," she said.
TVA officials on Saturday estimated it will be nine to 10 days for the worst damage to be repaired and all of the transmission system returned to normal operation.