The TVA Watts Bar Nuclear Plant is shown on Thursday, Oct. 22, 2015, near Spring City, Tenn. / Staff file photo

UPDATE: TVA has retracted the alert notice at Watts Bar Nuclear Plant. Read more here



The Tennessee Valley Authority idled one of the reactors at its newest nuclear power plant Wednesday after a gauge indicated a lower than expected level in one of its four steam generators and then, within 15 minutes of when workers shut down the Unit 1 reactor, workers detected smoke in a battery room in the control building.

TVA activated the lowest level of its emergency response to the potential fire at the Watts Bar Nuclear Power Plant at 9:52 a.m. Wednesday due to the smoke. But TVA spokesman Jim Hopson said plant workers determined there was no fire but only an overheated component that began smoking.

"We exited out of the "unusual event" status by 11:26 a.m. once we determined there was no fire or danger," Hopson said. "There was no safety concern for the plant, for the public or for any employee and there were no injuries. But it was the right decision to go to the notice of unusual event when we could not immediately determine if there was any fire risk."

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The Unit 1 turbine is painted dark blue inside Watts Bar Nuclear Plant's turbine building. / Staff photo by Tim Barber

The initial problem that caused the Unit 1 reactor at Watts Bar to shut down was determined to be a faulty control card that gave workers a false indication of a problem.

"We've replaced the component after we determined that it was not a physical problem but just a control issue and we're in the process now of bringing that unit back online,"Hopson said Thursday. "There were no safety issues and everything performed exactly as it was designed and the operators responded appropriately."

Typically, it takes one to three days to bring a reactor to full power from cold shutdown and TVA expects to have both reactors at Watts Bar operating at full power by this weekend. TVA's newest unit at Watts Bar was not affected by this week's shutdown.

The smoke detected at Watts Bar Wednesday was the first such fire risk activated by TVA at one of its three nuclear power plants since smoke was detected at the Unit 2 reactor at the Sequoyah Nuclear Power Plant in November 2018.

Contact Dave Flessner at or at 423-757-6340.