Columbia Water Hardness & Quality Report (2026)

The City of Columbia Water utility serves the City of Columbia and portions of the Greater Columbia Metropolitan Area in Richland County, South Carolina, providing drinking water to over 300,000 residents. Water is drawn from two surface sources: the Broad River via the Columbia Canal, treated at the Columbia Canal Water Treatment Plant for northern service areas, and Lake Murray on the Saluda River, treated at the Lake Murray Water Treatment Plant for the remainder of the city. Both plants employ coagulation, sedimentation, filtration, and chlorination before distributing finished water through the distribution system.

The Broad River and Saluda River watersheds drain the Piedmont physiographic province of South Carolina, underlain by ancient metamorphic and igneous rocks of the Carolina Terrane, including gneiss, schist, and granite. Lake Murray, a man-made reservoir impounded by the Saluda Dam within the Carolina Slate Belt, stores water amid granitic gneiss and amphibolite formations. This crystalline bedrock geology yields moderately soft water due to limited leaching of divalent cations from weathered Precambrian and Paleozoic metamorphic rock, with low buffering capacity compared to limestone-dominated karst regions.

Moderately soft water forms lather readily with less soap than harder supplies, reducing detergent use and leaving skin and fabrics softer without excessive fixture scaling. Impacts on appliances like water heaters and dishwashers are minimal, with only rare thin deposits that clean easily with vinegar. A water softener is not typically recommended, as the hardness level avoids both hard water buildup and the corrosivity of very soft water. The 2024 Water Quality Report confirms EPA compliance; a resolved chlorite exceedance at the Columbia Canal Water Treatment Plant was the only noted issue, and disinfection byproducts remain within regulated limits throughout the distribution system.