Lake Lanier is part of the Chattahoochee River system.

ATLANTA – The U.S. Supreme Court Thursday sided with Georgia in a lawsuit Florida filed in 2013 over the allocation of water that flows between the two states.

In a unanimous 9-0 opinion written by Justice Amy Coney Barrett, the court ruled that Florida failed to prove its allegations that Georgia’s water consumption from the Chattahoochee and Flint river systems caused the failure of Florida’s oyster industry in Apalachicola Bay.

“Florida allowed unprecedented levels of oyster harvesting in the years before the collapse,” Barrett wrote. “Georgia’s consumption had little to no impact on the bay’s oyster population.”

Florida claimed originally that increasing water consumption in rapidly growing metro Atlanta was causing unacceptably low flows where the Chattahoochee River enters Florida at Lake Seminole.

More recently, including during oral arguments before the Supreme Court in February, Florida’s lawyers put more of the blame on water consumption by farmers in the lower Flint River irrigating their crops.

Florida’s strategy shifted as water conservation efforts by municipal utilities in the Atlanta region began to pay off.

Gov. Brian Kemp hailed the decision as a “resounding victory” for Georgia and a vindication of the steps the state has taken to boost water-use efficiency.

“Our state will continue to wisely manage water resources and prioritize conservation, while also protecting Georgia’s economy and access to water,” Kemp said in a prepared statement.

“The Supreme Court … affirmed what we have long known to be true: Georgia’s water use has been fair and reasonable,” Georgia Attorney General Chris Carr added. “We will continue to be good stewards of our water resources, and we are proud to have obtained a positive  resolution to this years-long dispute on behalf of all Georgians.”

Florida’s lawsuit sought the court to place a cap on Georgia’s water consumption. Georgia’s lawyers argued such a cap would bring growth in metro Atlanta – and the region’s economy with it – grinding to a halt and devastate Southwest Georgia’s farm belt.

 Thursday’s decision doesn’t mean an end to the so-called tri-state “water wars” between Georgia, Florida and Alabama that have dragged on for three decades.

For one thing, Alabama is challenging an agreement Georgia and the U.S. Army Corps of Engineers signed in January that for the first time authorized the use of Lake Lanier as a water supply.

While the federally managed reservoir has been supplying water for decades, its use for that purpose has been among the legal issues contested during the water wars.