TVA considering changes to flood-control barriers

By Hugh G. Willett

Two years after spending millions to install sand baskets on four East Tennessee dams, the Tennessee Valley Authority is considering removing or replacing the controversial flood barriers.

In 2009 TVA installed "gambion" barriers made of wire mesh filled with sand or dirt on Fort Loudon, Tellico, Cherokee and Watts Bar dams to prevent overflow in the case of an extreme flood event. At the time, TVA described such an event as being so rare as to occur only once in a million years.

TVA representatives met with local residents for a public hearing in Lenoir City on Tuesday to discuss alternatives to the sand baskets, which have been criticized by some as unsightly and ineffective.

"This is really just the first step," said TVA spokesman Travis Brickey.

The sand baskets were never designed to be permanent, he said. In fact, one of TVA's options is to get rid of them altogether.

Brickey said TVA is looking at several options, including removing the baskets; replacing the baskets with a permanent concrete barrier; or some combination of both.

TVA is trying to balance the cost and aesthetics of the sand baskets against the probability of a maximum flood, he said. Also under consideration is protecting lives and property, including the agency's nuclear power plants downriver, he said.

State Rep. Jimmy Matlock R-Lenoir City, said he was encouraged by Tuesday's meeting but said he would have like to have seen such a get-together two years ago before the sand baskets, which were estimated to cost $4 million to $6 million, were put in place.

"Why was it done so quickly without a public hearing?" he asked.

Matlock said he has been in contact with in Tellico Village residents who have questioned both the methodology used to predict the maximum flood and the ability of the sand baskets to provide protection.

"When you look at how the baskets are placed, it's almost silly. There are large gaps where water can come through," he said.

The Tellico Village Homeowners Association formed a committee to work with TVA after a large number of residents protested the barriers back in 2009.

"We just want TVA to do a technically competent job," said Dennis Stanczuk, a Tellico Village resident with a background in geology and risk assessment.

Richard Comisco, a member of the Tellico Village committee said he was "shocked" when he first saw the sand baskets in place. "I just wasn't prepared for it."

Comisco said he believes TVA moved hastily to install the barriers after caving in to pressure from the Nuclear Regulatory Commission.

According to TVA, the application process for a new nuclear reactor at Bellefonte, Ala., spurred a review of the agency's modeling of probable flood conditions based on extreme storm events. The modeling showed that floodwaters might be higher than expected in extremely rare events.

"The NRC gave us a requirement to meet," said Bill Sitton, communications consultant for TVA.

Although he acknowledges that removing the flood barriers is one option, Sitton explained that TVA must still meet the NRC safety requirements.

TVA will prepare an environmental-impact statement to address the potential environmental effects of the permanent dam modifications. TVA will be seeking more public comment before making its decision, Sitton said.

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7/27/11