EAC: DNA tests find dog waste, not human sewage, fueling E.coli at Isle of Palms outfalls

Laura Levens, chair of the city's Environmental Advisory Committee, told council that targeted DNA testing at three stormwater outfalls found bacterial contamination but no human waste. "The good news is there was no human waste found," Levens said, and she added that test results pointed to dog waste as the main source of E.coli in those outfall areas.

Levens said the EAC used a two-step testing approach: a screening test for bacterial levels followed by DNA assays for human, dog and deer/elk sources. Although human contamination was not detected, the committee said elevated nutrients and dog-waste bacteria can harm Spartina marsh grasses and increase algal/oxygen-depletion risks.

Committee actions and next steps: Levens described education efforts at farmers markets and new signage, a pilot of bag-and-disposal stations (a no-cost community project for toy and cleanup bins), and plans for permanent dog-waste stations tied to future drainage projects. The committee intends to retest in about two years after installing disposal stations and pursuing outreach to measure progress.

Other EAC initiatives: Levens reviewed the city’s light-pollution work (an updated ordinance and a Bortle index benchmark), a hybrid litter-removal approach with Trident Waste (corrals and roll-out cans), native-plant projects and a planned resilience 101 training coordinated with the South Carolina Office of Resilience.

Why it matters: The committee framed the findings as actionable: they do not indicate failed wastewater infrastructure, but they identify a local source of fecal contamination that can be addressed through targeted outreach, disposal infrastructure and repeat testing to judge effectiveness.