Raritan River Pathogen Results for 09.03.2026

September 4, 2026

By J.M Meyer

The first pathogen monitoring session of the month took place on Thursday, September 3rd. 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.

This week, our sites received one to three inches in the 24 hours prior to water monitoring. This tends to flush feces into the water, and our results reflect this fundamental connection between precipitation and water quality.

Our lab results for water quality samples taken on Thursday, September 3rd, 2026, show Enterococcus bacteria levels exceeding the EPA federal water quality standard of 104 cfu/100mL at five of our regular monitoring sites this week. The problem sites are indicated by the red frown on the map and chart and include Riverside Park (Piscataway), Rutgers Boathouse (New Brunswick), Edison Boat Basin (Edison), Ken Buchanan Waterfront Park (Sayreville), and 2nd Street Park (Perth Amboy).

Green smiles on the chart and map indicate the sites with bacteria levels safe for recreation and include the following: Raritan Bay Waterfront Park (South Amboy).

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 has been our worst performing site over the past six years, we have started sampling at new sites in the vicinity. On September 3rd, we sampled the D&R Canal at Demott Lane for a fourth time since we started pathogens monitoring this season. The lab analysis produced 246 enterococci cfu per 100mL which fails to meet the EPA federal water quality standard of 104 cfu/100mL. For the first time, this site has failed the test!

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!

Art gallantly wades into the water next to the Combined Sewer Outfall in Perth Amboy. You can see a sanitary wipe in the foreground.
Nothing says “welcome to the park” like a Natural Green Lawn Care pesticide flag. The problem with spraying glyphosates and nitrogen fertilizer near the river bank is that much of it washes into the stream, damaging aquatic ecology. Spraying riverbanks is bad for the taxpayer and bad for the environment.
Mike grabbed more than five gallons of plastic and Styrofoam from the New Brunswick boat ramp. If we have to capitalize ‘Styrofoam’, maybe Dow Jones ought to capitalize our cleanups.
In New Brunswick, the pigeons carefully observed the water monitoring team. We tried to talk to the pigeons about volunteering for the Lower Raritan Watershed Partnership, but they ignored every entreaty. Some fowl folks have no sense of civic duty.
Taxpayer Mike Orsini has noticed that the beach in South Amboy suffers from runoff near the paved surfaces. With enough rainfall on impervious surfaces, the water quickly picks up enough energy to carry away the sand. An easy, affordable solution would be to install a swale to catch and filter the rainwater.
Before each session, the team charges the YSI and calibrates the sensors. Here, we can see the screen for calibrating pH, especially in the high (base) range of 10. That number is similar to bleach, and we have thankfully never encountered that in the Raritan.