S.C. Code § 4-3-150
Colleton County is bounded as follows: by a line originating at a point where the center line of the Big Salkehatchie River intersects the Bamberg County line; thence northeastward by its various courses following the Bamberg County line to its intersection with the center line of the Edisto River; thence southeastward and eastward following the center line of the Edisto River to its intersection with the center line of the South Edisto River; thence southward by the center line of the South Edisto River to a point at latitude 32° 30' 00.676" N, longitude 80° 21' 09.844" W (North American Datum 1983); thence southeastward from said point following a straight line extending to the center line of Big Bay Creek; thence eastward by the center lines of Big Bay Creek and Scott Creek to a point at latitude 32° 30' 57.711" N, longitude 80° 16' 35.854" W (North American Datum 1983) at the mouth of Jeremy Inlet; thence from said point following a line with a true azimuth of 145° (bearing of S 35° E) to the Territorial Sea boundary; thence southwestward following the Territorial Sea boundary to its intersection with a line having a true azimuth of 115° 30' (bearing of S 64° 30' E) extending from a point at latitude 32° 29' 06.078" N, longitude 80° 28' 36.683" W (North American Datum 1983) at the mouth of the Coosaw River; thence northwestward on said line from the Territorial Sea boundary to said point at the mouth of the Coosaw River; thence westward following the center line of the Coosaw River to its intersection with the center line of the Combahee River; thence northwestward following the center line of the Combahee River to its intersection with the center line of the Big Salkehatchie River; thence northwestward following the center line of the Big Salkehatchie River to a point where said line intersects the Bamberg County line, the point of origin.
S.C. Code § 4-3-150