S.C. Code § 6-7-1230
The governing authority of a municipality may establish an official map of the municipality. The governing authority of a county may establish an official map of the unincorporated areas of the county. Such official maps may show the location of existing or proposed public street, highway and utility rights-of-way, public building sites, and public open spaces. The official map may include the whole or any part or parts of the municipality or county within the jurisdiction of the establishing governing authority. The governing authority shall certify the fact of the establishment of the official maps to the clerk of the circuit court of the county.
The official map may consist of any number of separate maps which need not be drawn to the same scale; however, such maps shall be indexed on a single map depicting the area of jurisdiction of the governing authority.
S.C. Code § 6-7-1230