ATCHAFALAYA RIVER

distributary of the Red and Mississippi rivers in Louisiana, U.S. It branches southwest from the Red River near a point in east-central Louisiana where the Old River (about 7 miles long) links the Red River with the Mississippi, and it flows generally south for about 140 miles (225 km) to Atchafalaya Bay, an inlet of the Gulf of Mexico in southern Louisiana. Its length including the Red River is 1,420 miles (2,290 km), and its drainage area is 95,100 square miles (246,300 square km). The Atchafalaya, via the Old River, threatens to capture the major flow of the Mississippi; since the mid-20th century, however, a navigable system of dams, locks, and levees has kept the waters in check. Normally, some 25 percent of the Mississippi's flow is diverted into the Atchafalaya and the Atchafalaya Basin Floodway through the Old River Complex (Old River Control Structures), but during floods such as those of 1973 and 1993, the Morganza Floodway is utilized as well. Below Grand Lake (Six Mile Lake), at Morgan City, the river intersects the Gulf Intracoastal Waterway. Atchafalaya is Choctaw Indian meaning long river.