Arid East Tennessee forces TVA action on cooling nuclear plants

Arid East Tennessee forces TVA action on cooling nuclear plants

CHATTANOOGA (AP) — The Tennessee Valley Authority is having to alter the flow of the Tennessee River to keep its Sequoyah and Watts Bar nuclear plants cool amid one of the driest periods in years in East Tennessee.

The federal power agency cut back peak-power production at its Watts Bar hydroelectric dam last week when the temperature began to rise downstream in Chickamauga Reservoir, which provides cooling water for the nuclear stations.

An internal TVA memo obtained by the Tennessee Valley Energy Reform Coalition, a Knoxville-based watchdog group, said the warm water reduced the efficiency of the Sequoyah Nuclear Plant near Chattanooga.

Coalition leader Stephen Smith said Sequoyah lost the equivalent of 15 megawatts of power, enough to power 9,000 homes, during an 11-hour period June 15-16.

TVA spokesman John Moulton refused to confirm that. "We do not discuss amount of power loss for competitive reasons," he said Wednesday.

However, he said a more continuous flow of water from the Watts Bar Dam, along with cooler air temperatures, cooled the reservoir.

Under a lake management plan adopted a few years ago, TVA maintains a minimum flow of water through its dams to assure water quality.

Although TVA hasn't changed the amount of water being released, it has stopped under the present conditions from holding back water at certain times for hydroelectric power generation.

The agency must balance water flow against demands for keeping its lakes as high as possible for summer recreation. TVA has agreed not to begin a seasonal drawdown of the lakes until Aug. 1.

But the driest period in over a decade is challenging that.

Since August, average rainfall in the Tennessee Rivershed above Chattanooga has been 10 inches below normal. As a result, Nottely Lake in North Georgia isn't expected to reach its normal summer pool this year, and Cherokee Lake in East Tennessee might not reach its summer level until this week.

"It is very dry and there is very low runoff," Moulton said. "We are definitely monitoring the situation."

"But as we stand right now, we are continuing to provide minimum flow and we are also keeping the lakes at or above their minimum summer level, with the exception of one. If the dry weather continues, we will continue to look at it."