With Labor Day and the start of a new school year looming, throngs of New Yorkers will head to the beach this weekend, braving traffic, sunburns, maybe sharks — and Vibrio vulnificus, a nasty, flesh-eating bacteria that thrives in warm seas and brackish water.

The presence of bacteria in Long Island’s recreational and drinking water is closely monitored by the Suffolk and Nassau County Health Departments, with Enterococci and E. coli being the primary "indicator organisms" of concern. Enterococci are the standard markers used for marine (saltwater) beaches, while E. coli is used for freshwater areas; their presence suggests fecal contamination from sources like stormwater runoff, failing septic systems, or resident waterfowl populations. During periods of heavy rainfall, these bacteria levels can spike, leading to temporary beach closures to prevent waterborne illnesses such as gastrointestinal distress or skin and ear infections. In terms of drinking water, Long Island's aquifer system is generally well-protected, but there are ongoing concerns regarding Nitrates and chemical contaminants (like PFAS) rather than persistent pathogenic bacteria, which are typically neutralized by the public water treatment process. Residents are always encouraged to check the latest "Beach Monitoring" reports or their annual "Drinking Water Quality Report" for specific local data.