S.C. Code § 5-31-210
At any election for bonds held to meet the costs of acquiring property of the character referred to in Section 5-31-610 the elector shall vote for three citizens of the city or town whose terms of office shall be respectively two, four and six years and until the general election for municipal officers next following the expiration of the short term, and until their successors are elected and qualified. The classification above designated as to the term shall be ascertained by the commissioners after election by lot. At each general election for municipal officers following the expiration of the term of the commissioner holding the short term and at every such election every two years thereafter, one such commissioner shall be elected for a term of six years and until his successor is elected and qualified. The officers so elected and their successors in office shall be known as the commissioners of public works of such municipality and by that name may sue and be sued in any of the courts of this State.
In addition to the three members of the board of commissioners of public works of a municipality authorized above, the governing body of a municipality with a population of fifty thousand persons or less according to the 1980 official United States Census may provide by ordinance for the election of two additional commissioners. The new commissioners must be elected at a special election or at any general election following the enactment of the ordinance in the same manner that the other commissioners are elected. The new member receiving the highest number of votes in that election shall serve for a term of six years and the new member receiving the next highest number of votes in that election shall serve for a term of four years. Their successors must be elected in the election for municipal officers every four or six years thereafter for terms of office of six years. The members elected shall serve until their successors are elected and qualify. Vacancies in these two new positions must be filled in the same manner as other vacancies on the board of commissioners of public works are filled. The provisions of this paragraph for two additional commissioners apply only to boards of commissioners of public works founded after 1920.
S.C. Code § 5-31-210