TVA releasing dam water to reduce Tennessee River flooding

The Tennessee Valley Authority on Wednesday said it is working to move large volumes of water—as much as one million gallons per second in some places—along the Tennessee River system to reduce potentially damaging flooding from record rainfall.

TVA said it prepared for this event by lowering reservoir levels on the main channel of the Tennessee River beginning the last week of June, leaving some areas below normal for this time of year.

However, extreme rainfall and runoff in the middle and eastern portions of the Tennessee Valley over the past week are now forcing TVA to spill or release excess water from 10 of 20 tributary dams and all nine main channel dams along the 652-mile Tennessee River, a press release said.

“TVA’s management of the river system is working,” said Chuck Bach, general manager of TVA River Operations. “TVA will spill only when all available hydroelectric-generating turbines are operating at full capacity and additional water still needs to be moved.”

Spilling along the dams is expected to last one to two weeks, the press release said. As this water moves through the system, agricultural crops planted in floodplain areas along the Tennessee River in Northern Alabama and West Tennessee will be impacted by higher than normal water elevations.

“Some crop fields near the banks of the Tennessee River will see up to six to eight feet of water,” Bach said. “Crops along the Tennessee River on Kentucky Reservoir will be impacted the most.”

Because of flooding and high water flows on the Ohio and upper Mississippi rivers, water releases out of the Tennessee River system into the Ohio River at Kentucky Dam have been reduced. TVA said it is in close contact with the U.S. Army Corps of Engineers, which manages the Ohio and Mississippi rivers, and when flood stages there drop, more will be allowed to be discharged from Kentucky Dam.

Within the Tennessee River system, there have been reports of flooding in Chattanooga; Whitesburg and Florence, Ala.; and Savannah, Tenn., near Pickwick Reservoir, the press release said.

Some recreational areas along the Tennessee River have been temporarily closed because of high water. Recreation areas on Douglas and Watauga reservoirs in Tennessee and Wilson reservoir near Florence, Ala., are among those most impacted.

“We advise using extreme caution when near the dams, rivers, and tributaries,” Bach said. “Safety is the No. 1 priority, and river currents and speed are unpredictable.”

Watauga Reservoir, near Elizabethton Tenn., set a record lake elevation on Monday at 1,967 feet above sea level—about a foot higher than the previous record set last May, the release said.

A forecast of additional rain later in the week could add one or two more inches of water into the already-flooded system.

The Tennessee River watershed has one of the highest annual rainfall totals of any watershed in the United States, averaging 51 inches a year. So far in 2013, more than 40 inches of rain has fallen in the Valley.