The Edisto River Basin originates in the South Carolina Sandhills region and flows through the Upper and Lower Coastal Plain Regions and into the Coastal Zone region. It eoncompasses thirty (30) watersheds and some two million acres of the State. There are a total of 2,780 stream miles, 8,402 acres of lake waters, and 20,284 acres (31.7 square miles) of estuarine areas in the Edisto River Basin.

The confluence of Chinquapin Creek and Lightwood Knot Creek form the North Fork Edisto River, which is joined downstream by Black Creek, Bull Swamp Creek, and Caw Caw Swamp. The South Fork Edisto River accepts drainage from Shaw Creek, Dean Swamp Creek, Goodland Creek, and Roberts Swamp before merging with the North Fork Edisto River to form the Edisto River. Downstream from the confluence, the Edisto River is joined by Cattle Creek, Indian Field Swamp, and Four Hole Swamp. Prior to joining the Edisto River, Four Hole Swamp accepts drainage from Cow Castle Creek, Providence Swamp, Horse Range Swamp, and Dean Swamp. Downstream from the Four Hole Swamp, the Dawho River enters the Edisto River, and their confluence forms the South Edisto River and the North Edisto River, which both drain to the Atlantic Ocean.