The second pathogen monitoring session of the season took place on Thursday, May 28th. Each week during the summer, from May to October, the Lower Raritan Watershed Partnership and Rutgers Cooperative Extension of Middlesex County run a volunteer-based monitoring program along the Raritan River. We collect water quality samples at six non-bathing public access beach sites, provide our samples to the Interstate Environmental Commission for analysis in their laboratory, and report the results to the public. Our mission is to share this data with the community and partners to ensure the safe use of the Raritan river for all.

Our lab results for water quality samples taken on Thursday, May 28th, 2026 show Enterococcus bacteria levels exceeding the EPA federal water quality standard of 104 cfu/100mL at one of our monitoring sites this week. The problem site is indicated by the red frown on the map and chart: Riverside Park (Piscataway). Green smiles on the chart and map indicate the sites with bacteria levels safe for recreation, and include the following: Rutgers Boathouse (New Brunswick), Edison Boat Basin (Edison), Ken Buchanan Waterfront Park (Sayreville) 2nd Street Park (Perth Amboy).

Interestingly, while the presence of fecal coliform indicates the presence of fecal matter, it is not considered to be a good predictor of disease causing bacteria. Thus, our sites in New Brunswick, South Amboy, and Perth Amboy all received green smiley faces even though our samples had thousands of fecal colony forming units…

Pathogens/Enterococci levels are used as indicators of the possible presence of disease-causing bacteria in recreational waters. Such pathogens may pose health risks to people coming in primary contact with the water (touching) through recreational activities like fishing, kayaking or swimming in a water body. Possible sources of bacteria include Combined Sewer Overflows (CSOs), improperly functioning wastewater treatment plants, stormwater runoff, leaking septic systems, animal carcasses, pet waste, wildlife waste, and runoff from manure storage areas.

In order to better understand why Riverside Park, Piscataway is our worst performing site over the past six years, we have started sampling further upstream. On May 28th, we sampled the Raritan Canal, Lock 11 in South Bound Brook. The lab analysis produced an estimate of 41 enterococci per 100 mL. That’s good news for folks who fish or paddle in the canal!

Our goal in reporting these results is to give residents a better understanding of the potential health risks related to primary contact during water-based recreation. If you are planning on recreating on the Raritan this weekend, make sure to stay safe and wash up after any activities!