SURFACE WATER CONTAMINATION FROM URBAN STORMWATER RUNOFF IN CHARLESTON, SC
Sampling sites were identified using high resolution elevation data, known hotspots of flooding during rainfall or higher than normal tides. Water sampling involved collection of sheetflow or standing water using established methods. Residential, commercial, tourist areas of the Charleston peninsula were targeted for sampling.
Major ions using ion chromatography, trace metals using inductively coupled plasma mass spectrometry, and fecal indicator bacteria using an IDEXX quantitray method were analyzed for this study. Preliminary data suggest high ion, trace metal, and fecal indicator bacteria levels in the initial runoff. Numerous diffuse and nonpoint sources reflect these levels of chemical and bacterial indicators. It is expected that this compromised water quality impacts the Charleston harbor and its ecosystem. More data is being collected to produce a comprehensive map of contamination concentrations during storm events all over the peninsula, in order to identify the most problematic sources of contamination.