The Ocmulgee River () is a western tributary of the Altamaha River, approximately 255 mi (410 km) long, in the U.S. state of Georgia. It is the westernmost major tributary of the Altamaha. It was formerly known by its Hitchiti name of Ocheese Creek, from which the Creek (Muscogee) people derived their name. The Ocmulgee River and its tributaries provide drainage for some 6,180 square miles in parts of 33 Georgia counties, a large section of the Piedmont and coastal plain of central Georgia. The Ocmulgee River basin has three river subbasins designated by the U.S. Geological Survey: the Upper Ocmulgee River subbasin (hydrologic unit code 03070103); the Lower Ocmulgee River Subbasin (03070104); and the Little Ocmulgee River Subbasin (03070105). The name of the river may have come from a Hitchiti words oki ("water") plus molki ("bubbling" or "boiling"), possibly meaning "where the water boils up." Description The river rises at a point in north central Georgia southeast of Atlanta, at the confluence of the Yellow, South, and Alcovy rivers. Since the construction of the Lloyd Shoals Dam in the early 20th century, these rivers join as arms of the Jackson Lake reservoir. The river's source is formed at an elevation of around 530 feet above sea level. The Ocmulgee River flows from the dam southeast past Macon, which was founded on the Fall Line. It joins the Oconee from the northwest (241 miles downstream from Jackson Lake) to form the Altamaha near Lumber City. The Ocmulgee River Water Trail begins from Macon's Amerson River Park to the confluence near Lumber city and Hazelhurst, encompassing approximately 200 miles. Human use Four power plants in the Ocmulgee basin that use the river's water, including the coal-fired Plant Scherer in Juliette, operated by the Georgia Power Company. Plant Scherer is the seventh-largest power plant in the United States by capacity , and the largest to be fueled exclusively by coal. Fish fauna A diverse array of fish—105 species in twenty-one families—inhabit the Ocmulgee River basin. The family with the largest representation in the river basin is Cyprinidae (carp and true minnows), with 27 species. It is followed by Centrarchidae (sunfish), which has 22 species. The Ocmulgee basin contains ten species in the family Ictaluridae (catfish) and eight species of in the family Catostomidae (suckers). The river basin is also inhabited by one State of Georgia-designated endangered fish species, the Altamaha shiner (Cyprinella