Area utility officials received word Tuesday from the Tennessee Valley Authority (TVA) that an agreement has been reached over the reduction of the flow of water from Normandy Reservoir.
Officials had been waiting for issues between the federal utility and environmentalists to be ironed out before the reduction could occur.
It has been the fate of a rare river creature, the birdwing pearly mussel, which has held up the reduction, with TVA required to complete an environmental report before it can cut the flow.
Meanwhile, the region moves closer to mandatory water restrictions as the level of the lake continues to drop.
Jim Allen, spokesman for TVA said Tuesday morning that the utility had reached an agreement with the state of Tennessee to reduce the release of water from the Normandy Dam reservoir.
"The environmental assessment which is required by the Endangered Species Act is nearing completion and TVA should be able to begin a gradual reduction of flow from the reservoir by mid week. That's pending any unforeseen finding" as a result of the assessment, said Allen.
According to Shelbyville Power, Water and Sewerage System general manager David Crowell, Tennessee Department of Environment and Conservation (TDEC) were still negotiating with TVA on Monday over a rate of release from the dam between now and Dec. 1. All of the local utilities are supportive of the reduced release schedule, Crowell said.
Randall Braker, general manager for Duck River Utility Commission (DRUC), said Monday he is hoping that the announcement is imminent, saying that the flow reduction was expected several days ago. DRUC supplies water for Tullahoma and Manchester.
TVA has completed the environmental assessment of the mussel that was required by TDEC, Tennessee Wildlife Resources Agency and U.S. Fish and Wildlife Service, Braker said Monday afternoon, and has been transmitted for approval.
Crowell said that TVA is looking to reduce the release of water in two steps, dropping from 155 cubic feet per second (cfs) to 140, let that release rate continue for two weeks, and then lower the rate to 120 cfs, which would normally be the target set for Dec. 1. Only 10 cfs of water is flowing into the reservoir at this time.
Area officials had expected the flow reduction to come earlier, but it hasn't happened due to the concerns over the mussel. Currently, the rate of water leaving the dam is 164 cfs, which is required from TDEC to supply the Shelbyville Wastewater plant with an adequate flow as well as Columbia, based on waste assimilation studies done in the 1980's.
"It's up to TDEC to relieve that requirement," Crowell said Monday, "And apparently they're going to, but TVA has had to do some environmental analysis ... that's what they're waiting on."
A statement made late Monday afternoon from Bridgette Ellis, senior VP of TVA environment and research, said it was her understanding "that it will be in increments just to see what impact there could be downstream, principally on the Birdwing Pearly Mussel."
"I think that once it's a go, we'll know what the steps are and what gradual means. My understanding is that it will be gradual until it reaches 120 cfs, and this is what the state asked for. That it be done gradually to allow assessment of the impact down stream."
Braker said the request to cut the flow from Normandy back has come from many water systems, "and that request has been under consideration for a long time now," adding that local officials started looking that the situation in June.
But nothing was done seriously until the end of August, Braker said. "There were some people that said there wasn't going to be a problem because it's going to rain and everything will be fine. But it didn't rain and people started to realize that there was a serious problem."
Meetings were held in Columbia in late September with area utility officials who make up the Duck River Agency Technical Advisory Committee (DRATAC). Braker said there was consensus from all involved that something had to be done immediately "and instead of a small cutback, five percent, they were talking about a 20 to 25 percent cutback."
Officials were optimistic that the flow cutbacks would be put into place on Oct. 1, but concerns were raised about the mussels at that time, which has held up the flow reduction by 15 days.
Most of the water in the river is used for flow maintenance, Braker said, for fish and wildlife requirements and for the wastewater plant. "Cutting back on your water consumption has very little impact," he said, adding that outdoor use is a bigger issue, since most of the water used indoors by city customers goes back into the river through the sewer system.
Some rain was in the forecast for today, but Crowell said the area is going to need a whole lot more before the situation improves.
"It's still looking serious toward next spring and summer unless we have a very wet winter and spring and we're not going to get up back to levels (on the lake) where TVA and TDEC want it to be."
Much of the water that flows from the dam to Shelbyville is soaked into the ground due to the unprecedented drought. Hopefully cooler weather will result in less evaporation, Braker said.
However, Braker stressed that if the shortage continues, DRUC will be the first to feel the effects, with Tullahoma and Manchester treatment plants not able to get any more water. They are working to obtain temporary pumps to slide down further into the lake to get water, which could cost the Coffee County utility around $100,000.
But Braker says if the drought continues beyond that, eventually TVA or the state will have to make a decision to either let the lake run dry, or close it "to keep everything in the lake from dying."
"Someone is going to have to say, 'We have to stop letting water out of the lake because the lake is literally going to run out of water and will kill everything in it,'" Braker said. "At that point, we're all out of water, from Manchester and Tullahoma, all the way to Columbia. A quarter of a million people -- no water."
Senior Staff Writer Clint Confehr contributed to this report.