ATLANTA (AP) -- Georgia leaders say that conservation rules are reducing water use in metro Atlanta as they fight with Florida over water rights, but it's not entirely clear why consumption has dropped.
Florida asked the U.S. Supreme Court earlier this month to determine how much water Georgia can take from the Chattahoochee and Flint Rivers. They merge at the Florida line to form the Apalachicola River, which flows into the Gulf of Mexico and feeds a vital oyster fishery. In the lawsuit, Florida officials say metro Atlanta and its thirsty suburbs use too much water and kill off Florida's oysters.
It's the latest version of a water feud between Alabama, Florida and Georgia that traces back more than 20 years. Georgia officials say the river system is now flush with record rainfall and that other factors, include overfishing, contributed to the oyster die-off. They are building a political defense around the idea that metro Atlanta is using less water.
"Our conservation efforts have decreased metro Atlanta's water use even as our population has grown substantially, and Georgia offered a framework for an agreement which never received a response from Florida," said Brian Robinson, a spokesman for Gov. Nathan Deal, in an Oct. 1 statement responding to the Florida lawsuit.
Various measures show that water use in metro Atlanta has decreased. Information collected by Georgia's Environmental Protection Division shows that water usage by the nine counties surrounding Atlanta dropped about 2 percent last year compared to 2010, when Georgia adopted a law setting conservation requirements. That data does not measure agricultural usage.
Conservation rules adopted in 2010 took effect during different periods. They banned outdoor lawn watering between 10 a.m. and 4 p.m. to limit evaporation losses. They gave local governments the power to restrict water use even in the absence of a drought. Public water systems were forced to conduct annual audits for leaks.
A 2011 study by the Metropolitan North Georgia Water Planning District noted similar trends over a longer period. Individual water use dropped from about 149 gallons per day in 2000 to 102 gallons in 2009. However, multiple factors were at play. While overall usage was declining, the big reductions seen from 2007 to 2009 were largely due to emergency drought restrictions, a severe economic recession and wet weather in 2009, according to the district's analysis.
"Yeah, the numbers look good but I think that I would say that you can't look at that decline and simply say it was the result of proactive management or some sort of willing, interested conservation," said Chris Manganiello, the policy director at the Georgia River Network. He said emergency drought restrictions and an economic downturn almost certainly helped bring down water use.
Usage may be down, but those living south of Atlanta do not consider the larger problem solved.
"While Atlanta-area communities have finally started to implement some conservation measures, those efforts are a drop in the bucket," said Jennifer Ardis, a spokesman for Alabama Gov. Robert Bentley. "Even the most aggressive conservation measures will not reduce Atlanta's consumption to a legal level that reflects Atlanta's fair share."
Alabama officials argue that the most important figures are water usage during dry periods, not annual averages. During dry periods, water use upstream in Atlanta has the greatest effect downstream.
Environmental officials in Georgia say they believe conservation has cut demand, though it's difficult to say by how much. The Great Recession that started in 2008 crushed the economy, likely reducing the amount of water used in industrial production as output slowed. Fewer people were moving out on their own and forming new households with kitchens, sinks, lawns and dishwashers.
Lebone Moeti, acting program manager of the surface water withdrawal program at the Environmental Protection Division, said he believes conservation has an impact.
"There are so many variables that you need to take into account," Moeti said. "Conservation is something we're very keen on pushing. ... Now the question is how does one quantify the effects?"