The Floridan aquifer system, composed of the Upper and Lower Floridan aquifers, is a sequence of Paleogene carbonate rock which spans an area of about 100,000 square miles (260,000 km) in the southeastern United States. It underlies the entire state of Florida and parts of Alabama, Georgia, Mississippi, and South Carolina.
The Floridan aquifer system is one of the world's most productive aquifers and supplies drinking water for nearly 10 million people. According to the United States Geological Survey, total withdrawals from the Floridan aquifer system in 2000 were ranked 5th highest of all principal aquifers in the nation at 3,640 million gallons per day (Mgal/d) (13.8 million m/d; 11,200 acre⋅ft/d). Of the total, 49% (1,949 Mgal/d; 7.38 million m/d; 5,980 acre⋅ft/d) was used for irrigation, 33% (1,329 Mgal/d; 5.03 million m/d; 4,080 acre⋅ft/d) was used for public water supply, 14% (576 Mgal/d, 2.18 million m/d; 1,770 acre⋅ft/d) was used for industrial purposes, and 4% were domestic self-supplied withdrawals. The Floridan aquifer system is the primary source of drinking water for most cities in central and northern Florida as well as eastern and southern Georgia, including Brunswick, Savannah, and Valdosta.
