Hanahan Water Hardness & Quality Report (2026)

Hanahan, South Carolina is served by the Charleston Water System, a major regional utility supplying approximately 400,000 residents across Berkeley, Charleston, and Dorchester counties. The system operates the Hanahan Water Treatment Plant, a facility over 100 years old that has undergone major modernizations to ensure continuous safe drinking water delivery. Water is sourced from two primary surface supplies: the Bushy Park Reservoir (approximately 90% of the blended supply) and the Edisto River (approximately 10%), which are treated and blended before distribution to the service area.

Hanahan's water supply originates from the Atlantic Coastal Plain watershed, characterized by Cretaceous and Tertiary sedimentary formations. The Bushy Park Reservoir and Edisto River both drain through this geologically young coastal plain terrain, which contains moderate concentrations of dissolved minerals, particularly calcium and magnesium. The surface water sources and underlying geology result in a moderately mineralized water supply typical of the Low Country region, reflecting the character of Cretaceous and Tertiary coastal plain sediments.

At the moderately hard classification, Hanahan residents may experience some scale buildup in water heaters, kettles, and plumbing fixtures over time. Dishwashers and washing machines may require adjusted detergent amounts, and soap may not lather as readily as in softer water areas. Most households do not require water softening systems, though those with high-use appliances may choose point-of-use softeners. Regular descaling and periodic flushing of water heaters are recommended. Water quality testing in the 29410 ZIP code has identified contaminants including bromodichloromethane, lead, and dichloroacetic acid above EPA health-based guidelines. The Charleston Water System provides free lead testing at multiple office locations, including a site at 6330 Murray Drive in Hanahan.