GAINESVILLE — This weekend’s rain lessened the strain on Lake Lanier, an official from the U.S. Army Corps of Engineers said at Tuesday’s water forum at the Georgia Mountains Center.
Jonathan Davis, representing the corps at Gainesville’s drought management forum, told the crowd of more than 100 people that although there was not a lot of rain in the northern area of the state over the weekend, the rain in southern Georgia allowed the corps to release less from Buford Dam this week.
Columbus received more than 2.5 inches of rain between Sunday and Monday. That rainfall, though it did not affect Lake Lanier’s level, added to the amount of water flowing through the lower Chattahoochee and the Flint Rivers, and supplemented the required 4,750 cubic feet per second that must flow through the Apalachicola River to protect endangered mussels and sturgeon, Davis said.
Because of the increased flows in the lower Chattahoochee and Flint Rivers, Lanier will not have to release as much water this week as it did last week.
"We were releasing on average about 2,100 cubic feet per second (from Lake Lanier)," Davis said. "As a result of this rain in the lower basin ... we’re now to be able to reduce that — cut it almost in half — to about 1,200 cubic feet per second being released from Lake Lanier for the next several days."
Davis said if the state received more rain, the amount released from Lanier could be further reduced.
"Rain anywhere is good," he said.
Davis also said that the corps’ "exceptional drought operations" reduced the amount required to flow to the Apalachicola River from 5,000 cfs to 4,750 cfs. If drought conditions worsen, the corps can reduce the flows to 4,500 cfs and again to 4,150 cfs.
Jeff Fleming, who represented the US Fish and Wildlife Service at the forum, said the service has been working closely with the corps over the last three to five months to assess the health of the ecosystem where the endangered mussels and gulf sturgeon live in the Apalachicola River below Woodruff Dam.
"We immediately agreed with the corps that they could go to 4,750," Fleming said.
The service is working to find out what flows are acceptable to support the endangered species, Fleming said. Historic flows below Woodruff Dam have been around 5,000 cfs, but the lack of data concerning less water flowing through the dam make it difficult to discern what water levels are safe for the endangered species.
"This is going to be an interesting opportunity for us to learn more about the impacts of these species as water levels decline beyond historic levels," Fleming said.
The service has agreed to allow the corps to reduce flows from Woodruff Dam to 4,150 cfs in the future if drought conditions continue to get worse, Fleming said.
One member of the crowd asked why the flows could not be reduced to 4,150 cfs immediately instead of in increments.
"Because this is uncharted territory, we wanted to go slowly," Fleming said. "It’s prudent, frankly, to go slow, and adopt triggers that will allow us to incrementally reduce the flows in an effort to avoid (jeopardizing the species)."
The flow levels are important to the mussels, because they usually live in 12 to 36 inches of water or close to the higher banks of the river, Fleming said. If the flow levels are reduced immediately, it could jeopardize the mussels’ habitat.
"If you incrementally reduce those flows, it gives those species time to move," Fleming said.
In response to a question from the crowd about the importance of the mussels and sturgeon, Fleming said the service was obligated by Congress to protect the species, but the mussels’ health is connected to human health.
"When you have these aquatic species that are struggling to do well, it’s an indicator that the aquatic health of the system is not doing so well," Fleming said. "That ultimately impacts us as a citizenry. When you have these species’ that are struggling, it’s a signal that we need to pay attention to water quality and a whole range of things."