Commercial production of catfish in west-central Alabama began about 1970, and by 1991 catfish ponds covered about 16,000 acres in the Black Belt area of the State. The rapid increase in catfish farming or aquaculture and the associated demand for ground water led the U.S. Geological Survey in cooperation with other Federal and State agencies in 1990 to initiate a study to better define the ground-water resources in the Black Belt area.
The major aquifers in the study area are sand and gravel beds in the Eutaw, Gordo, and Coker Formations. Recharge to these aquifers occurs primarily in areas where those formations crop out. The average recharge to the major aquifers in the study area, as estimated from baseflow analysis of streams in the outcrop area, is 11.4 inches per year.
Water from the major aquifers in the study area generally is of good quality and suitable for most uses. Water from the Eutaw aquifer, however, contains chloride in concentrations greater than 500 milligrams per liter in central Greene County and in downdip areas in Marengo and Wilcox Counties and is not suitable for public water supply. Some ground water with elevated chloride concentrations is used for catfish farming in these areas, however.
The total estimated water use for aquaculture in the study area in 1990 was 21.83 million gallons per day, 16.08 million gallons per day from ground-water sources, and 5.75 million gallons per day from surface water sources. About 13.54 million gallons per day of water was used for filling catfish ponds and an additional 8.29 million gallons per day was used to replace evaporation losses.
