Florida v. Georgia, 592 U.S. 433

Background

Florida (downstream) sued Georgia (upstream) in the Supreme Court’s original jurisdiction, seeking an equitable apportionment of waters in the Apalachicola‑Chattahoochee‑Flint Basin, alleging Georgia’s overconsumption caused sustained low Apalachicola flows that devastated Florida’s oyster fishery and river ecosystem.
The Basin includes Chattahoochee and Flint Rivers (originating in Georgia), Lake Seminole at the state line, and the Apalachicola River flowing into Apalachicola Bay; the U.S. Army Corps of Engineers operates reservoirs that affect flows.
The Apalachicola oyster population collapsed in 2012 during a severe drought; Florida links the collapse to Georgia’s water use (via increased bay salinity → predators/disease), while Georgia attributes it to Florida’s overharvesting, inadequate reshelling, drought, and Corps operations.
After initial proceedings and remand for further findings, Special Master Kelly concluded Florida failed to prove by clear and convincing evidence that Georgia’s consumption caused serious injury to oysters or river species and recommended denial of relief.
The Supreme Court performed an independent review, adopted the Special Master’s findings, overruled Florida’s exceptions, and dismissed the case.

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Burden of proof / standard	Florida must prove serious injury and causation by clear and convincing evidence but can obtain relief if shown	Georgia: Florida must meet exacting standard for sovereign vs. sovereign dispute	Court: Florida concedes and Court applies clear and convincing standard; burden is exacting for interstate apportionment
Cause of oyster collapse	Georgia’s overconsumption → low river flows → higher bay salinity → increased predation/disease → oyster collapse	Florida mismanaged fishery (overharvest, low reshelling); drought and Corps operations explain low flows/salinity	Held: Florida failed to prove by clear and convincing evidence that Georgia’s consumption was a substantial causal factor; causation not established
Harm to river wildlife/plants	Low flows from Georgia’s use disconnected tributaries/sloughs and caused serious injury to fish, mussels, trees	Lack of data showing population declines; harm metrics do not translate to real-world injury	Held: Insufficient evidence; Special Master correctly found a "complete lack of evidence" of serious species injury
Redressability / remedy effect	Reducing Georgia’s consumption would increase Apalachicola flows and redress Florida’s injuries	Corps reservoir operations and limited modeled effects mean decree may not produce meaningful redress	Held: Court focused on causation failure; earlier remand had required findings on redressability but dismissal followed because causation not shown

Key Cases Cited

Kansas v. Nebraska, 574 U.S. 445 (2015) (Court must conduct independent review in original‑jurisdiction interstate disputes)
Colorado v. New Mexico, 459 U.S. 176 (1982) (requiring a complaining State to prove serious injury to obtain equitable apportionment)
Colorado v. New Mexico, 467 U.S. 310 (1984) (describing clear‑and‑convincing proof requirement in interstate water disputes)
New York v. New Jersey, 256 U.S. 296 (1921) (serious‑magnitude injury standard in equitable‑apportionment context)
United States v. Detroit Timber & Lumber Co., 200 U.S. 321 (1906) (syllabus/headnote does not constitute part of Court’s opinion)