S.C. Code § 49-17-810
After any such drainage district shall have been declared established, as aforesaid, and the survey and plan thereof approved, the clerk of the court shall appoint three persons who shall be designated as the board of drainage commissioners. Such drainage commissioners shall first be elected by the owners of the land within the drainage or levee district or by a majority of them in such manner as the clerk shall prescribe. The clerk shall appoint those receiving a majority of the votes. If any one or more of such proposed commissioners shall not receive the vote of the majority of such landowners the clerk shall appoint all of the remainder from among those voted for in the election in the order of those receiving the greatest number of votes. Any vacancy thereafter occurring shall be filled in like manner.
S.C. Code § 49-17-810