S.C. Code Ann. § 6-13-250

The rates charged for services furnished by the system, as constructed, improved, enlarged, and extended, shall not be subject to supervision or regulation by any state bureau, board, commission, or like instrumentality or agency thereof. However, the board must provide to the Office of Regulatory Staff by July first each year, for information purposes, in such form as the Office of Regulatory Staff may designate, schedules showing all rates, service rules and regulations, and forms of service contract established by the board.