Alabama officials have declared an emergency at a nuclear power plant in the northern part of the state and have started shutting it down in the aftermath of severe storms and tornadoes that have pounded the state.

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Tennessee Valley Authority began the process Wednesday afternoon, declaring an 'unusual event,' the lowest of four emergency levels as the storms damaged electricity transmissions lines powering the plant.

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This afternoon, the Browns Ferry plant, because of the loss of transmission declared an unusual event, which is the lowest of the four emergency classifications used by the Nuclear Regulatory Commission and personnel are working to safely shut down the plant, said Tennessee Valley Authority Chief Operating Officer Bill McCollum in a video posted to the Authority's web site.

The Browns Ferry plant contains three nuclear units and is being shut down this afternoon after the transmission line damage took the plant offline, McCollum said.

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He said all of the systems at the plant functioned as designed and normal procedures were being used to cool down the plant.

The plant's units combine to give it 3,274 megawatts of power.

A spokeswoman said backup diesel generators started and operated as designed, according to Reuters.

The Brownsferry plant has the same design and age as the Fukushima Daiichi plant in Japan, which was damaged when a tsunami in the aftermath of a 9.0 magnitude earthquake knocked out power and water damaged emergency backup units.

Browns Ferry's nuclear reactors are of the Mark 1 type by General Electric, similar to those at Fukushima.

Preston D. Swafford, TVA's chief nuclear officer said on a March 26 tour of that plant that Browns Ferry was ready for a one-in-a-million-year flood, or however many zeroes you want to go out, according to the New York Times.