If the Georgia-Alabama-Florida water wars were a poker game, Georgia's high card might be an agreement it secured in 2003 for rights to about a quarter of the water in Lake Lanier, a huge federal reservoir outside Atlanta.
The agreement with the U.S. Army Corps of Engineers — which Alabama and Florida claim is illegal — is the foundation of Georgia's long-term water plans, giving the Atlanta region the water it needs to continue growing as one of the nation's major cities. As a signed pact with the federal government, the deal also puts Georgia in a strong negotiating position with its neighbors.
But with the governors of the three states meeting next week for White House-backed mediation, Georgia is in danger of losing its ace in the hole.
A federal appeals court is expected to issue a decision in the coming months that could invalidate the state's rights under the agreement. The ruling could dramatically change the dynamic in the states' decades-long water wars, and observers say the governors' talks might not get very far with such a crucial decision looming.
"It is pivotal," said Mark Crisp, an Atlanta water consultant with C.H. Guernsey & Company who has testified as an expert witness in the case. "This (water allocation) is one thing that we do have finality on. If it suddenly goes away, it's all back into a big pot of soup."
No one argues that Atlanta shouldn't get any water from Lake Lanier, which provides most of the metro area's drinking water. The Atlanta metro area's population is about 5 million.
But even Georgia supporters acknowledge that the state's case to get nearly one-fourth of the lake's capacity did not fare well during oral arguments last month before the federal appeals court's Washington, D.C., circuit.
A three-judge panel sharply questioned whether the Corps had the authority to grant Georgia the allocation given that federal law says only Congress can sign off on significant changes to water allocations from reservoirs.
A Justice Department attorney representing the Corps struggled to explain the legal rationale, and he acknowledged that the Lanier agreement marks the largest operational change at a federal reservoir that the agency has sought without first going to Congress.
"Without congressional approval, the problem you're having here ... is trying to explain why this isn't a major operational change," Judge Laurence Silberman said.
Georgia currently uses about 10 to 15 percent of the capacity in Lake Lanier for drinking water, Crisp said.
As Atlanta has exploded with growth, Georgia and the Corps say it makes sense to shift the lake's use toward drinking water and away from its original purpose of producing hydropower. The deal they reached in 2003 would give Georgia about 23 percent of lake's capacity to meet future demand.
But Alabama and Florida counter that Georgia has no legal right to the Lanier water it's already using, much less to take almost a quarter of the lake over the coming decades. Atlanta's withdrawals, they argue, would dry up river flows into their states that support smaller municipalities, power plants, commercial fisheries and industrial users like paper mills.
With a record drought gripping much of Georgia and Alabama, the White House recently brokered a temporary arrangement under which the Corps would hold more water in Lanier while governors Sonny Perdue of Georgia, Bob Riley of Alabama and Charlie Crist of Florida try to hash out a longer-term agreement. The governors are slated to meet Dec. 11 in Tallahassee.
The court's decision — expected by early next year — could fuel a new round of legal activity, or it could prod the governors into more intense negotiations.
"If the court reverses, it does not mean that Georgia's water supply will be cut off. It simply means that the longer-term contracts for the water supply will have to wait another day," said Bruce Brown, an attorney representing Georgia.
Regardless of the ruling, he said, as the dispute moves forward, "it's a very difficult position for Florida and Alabama to say that Lanier shouldn't be used for water supply. It's like saying that I-95 shouldn't be used for trucks."
Georgia already is arguing in a separate case that drinking water has always been an intended purpose of Lanier. Crisp said Georgia's first step if it gets an unfavorable decision from the Washington appeals court would likely be to pursue that case.
But it would have to do so in the context of several other lawsuits that have been bundled in a U.S. District Court in Florida. And without any clear legal contract for Lanier water, its standing would grow much more uncertain.
"It would certainly change the relationship," said Parker Thomson, an attorney representing Florida. "It certainly would put everyone back where they were."
The case also could have national implications over how the Corps allocates water reservoirs, Thomson said.
"It really raises the question of when can the Corps do this without going to Congress to redefine uses of water in a lake," he said. "I think it will be a very significant decision."