ATLANTA — Federal scientists could revise their estimate of how much water Florida's Apalachicola River needs to prevent the deaths of an endangered mussel, a development that could give Florida more legal leverage in a long-running water dispute with neighboring Georgia.
U.S. Fish and Wildlife Service researchers are revisiting a 2008 report that found keeping the river flowing at a minimum of 5,000 cubic feet per second would not threaten the existence of the endangered fat threeridge mussel. But in September, scientists reported that the mussels had moved higher on the riverbank than during the drought-stricken period when the study was completed.
As many as 1,200 endangered mussels were exposed to the air in September when river levels dropped, said Donald Imm, a project leader for the U.S. Fish and Wildlife Service in Panama City, Fla. It's not clear whether they died.
"These mussels, they are really a canary-in-the-coal-mine indicator," he said. "If we lose the mussels, who knows what else we've lost from the natural system."
The report, scheduled for release Aug. 1, could have consequences in a long-running feud between Alabama, Georgia and Florida over regional water use.
Florida has asked the 11th U.S. Circuit Court of Appeals in Atlanta to overturn a ruling by U.S. District Court Judge Paul Magnuson, who refused last year to order the release of more water from Georgia reservoirs, including Lake Lanier, into the Apalachicola River to protect the gulf sturgeon, the fat threeridge mussel and the purple bankclimber mussel. The appellate panel has delayed the case until Imm's team completes its work.
State leaders have fought for years over water usage. Alabama and Florida accuse metro Atlanta of using so much water upstream that it leaves too little for those downstream.
In 2009, Magnuson ruled that metro Atlanta had little right to withdraw water from Lake Lanier on the Chattahoochee River, the main water source for roughly 3 million people. Magnuson said he will severely restrict the amount of water that Atlanta can use starting in 2012 unless political leaders in the three feuding states strike an agreement.
Georgia authorities have appealed that ruling while pursuing negotiations with Alabama and Florida.
"Because new information has come to light and the agencies are engaged in further administrative action, this litigation is likely to be affected," said Parker Thompson, an attorney for Florida, in a court filing requesting the delay in the Florida appeal. He declined to comment further.
Georgia attorney Todd Silliman said he could not comment in detail until federal scientists file their report.
"We understand why they're undertaking this additional consultation and we'll just have to see what the results of it are," he said.
When scientists conducted the last study, a severe drought had starved the river of water. Mussels feed at the river's surface and have some ability to follow changing waterlines. The ongoing study will examine the mortality rate of mussels, their ability to move with river's surface and how quickly they die when exposed to air.
The U.S. Army Corps of Engineers uses research from the U.S. Fish and Wildlife Service to decide how much water should be released from upstream reservoirs, including Lake Lanier, into the Apalachicola River, which flows down the Florida Panhandle.