TVA marks 90th anniversary with Raccoon Mountain plant tour

Staff Photo by Olivia Ross / Tour participants begin their tour at the generator bay. Celebrating its 90th anniversary, TVA allowed members of the public to tour the Raccoon Mountain pumped-storage plant Friday. Tours are limited to 20 people; participants are selected through random drawing. Registration for future tours can be found on the TVA website.

A dozen Tennessee Valley Authority customers got a rare look Friday inside the pumped-storage facility atop and inside Raccoon Mountain just west of Chattanooga.

The tour of TVA's only such facility, which uses an upper reservoir to store water to produce power when it is needed the most, was part of the 90th anniversary celebration this spring for the Tennessee Valley Authority. TVA was created as part of President Franklin Roosevelt's New Deal in 1933, and today, serves about 10 million customers in seven states as the nation's biggest government utility.

The Raccoon Mountain pumped-storage facility was completed in 1978 at a cost of $310 million. The power plant includes a 523-acre lake atop the mountain capable of storing 107 billion gallons of water. Its four generating units can produce up to 1,652 megawatts of power when in full operation, or nearly as much power as the Sequoyah Nuclear Power Plant, for short periods.

TVA had to shut down Raccoon Mountain from 2012 to 2014 to make nearly $90 million in repairs because of a design flaw that cracked some of the rotors in the hydroelectric station. But during the past decade, Raccoon Mountain has helped TVA balance its generation with varying load demands.

— Compiled by Dave Flessner