The Dorchester County system is a combined waterworks and sewer system owned and operated by the County through its Water and Sewer Department and serves a portion of Dorchester County. The County held a successful referendum in 1981 which authorized the County to provide water and sewer services.  Prior to that time, water and sewer service was provided by municipalities and private developers which constructed and operated water and sewer systems within particular areas of the County.

Water service is provided in portions of the County by the Department, the Town of Summerville Commissioners of Public Works, Charleston Water Systems, the Town of Ridgeville, the Town of Harleyville, the Town of St. George and the Dorchester County Water Authority, a special purpose district with authority to serve certain assigned areas of the County not served by other water providers.  Of the total area of the County of 575 square miles, the Department’s designated service area includes 359 square miles, of which 12 square miles is presently being served.

The Department provides sewer service to residential, commercial and industrial users in the portion of the County south of Four Holes Swamp through a system of pump stations and transmission lines with treatment at the Lower Dorchester County Wastewater Treatment Plant ("WWTP") prior to discharge via Coosaw Creek into the Ashley River. Expansion of the WWTP to increase treatment capabilities to 10 million gallons per day ("MGD") was completed in July 2008.