Category: LRWP Blog

Raritan Pathogens Results 7.10.25

By Danielle Bongiovanni and J.M. Meyer

The second pathogen monitoring session of the month occurred on Thursday, July 10. Every Thursday 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 on Friday afternoons. 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, July 10, 2025 show Enterococcus bacteria levels exceeding the EPA federal water quality standard of 104 cfu/100mL at THREE (3) of our monitoring sites this week. Problem sites are indicated by red frowns on the map and chart which includes: Riverside Park (Piscataway), Rutgers Boathouse (New Brunswick), 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), Ken Buchanan Waterfront Park (Sayreville), and Edison Boat Launch (Edison Township).

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, and runoff from manure storage areas.

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 Fourth of July weekend, make sure to stay safe and wash up after any activities!

Trash and an oily, translucent scum float on the water in New Brunswick. Photo credit: Ashley Fritz.
An overcast day at Edison Boat Basin fills the water with reflected clouds. Photo credit: Vanishri Murali.
A great egret (Ardea alba) swoops over the Raritan River. Photo credit: Vanishri Murali.
The cloudy sky is reminiscent of the smoke that once pumped out of Sayreville’s now-decommissioned coal-burning power plant (pictured), and Sayre and Fisher Brick Company kilns (long gone). Photo credit: Vanishri Murali.
Gavin, a young outdoor enthusiast from Maryland, met up with the LRWP in South Amboy and volunteered to help Dr. John use the sonde. Photo credit: Vanishri Murali.

Another week completed! The team in South Amboy. Photo credit: Vanishri Murali.

Build your own canoe paddle workshop!

July 9-August 13, 2005 @ 6pm-8pm

Learn woodworking basics and build your own paddle with the Lower Raritan Watershed Partnership!

The program will run out of the LRWP Boat House, 101 Raritan Avenue / Highland Park, NJ 08904

We will meet for five (5) Wednesday evening sessions, 6-8pm:

July 9 Paddle Building in Workshop

July 16 Paddle Building in Workshop

July 23 Paddle Building in Workshop or optional Canoe Paddle on the Raritan River (Donaldson Park – Highland Park

August 6 Paddle Building in Workshop

August 13 Paddle Building in Workshop

Pre-registration required, space is limited

$75 covers instruction, materials cost, and all equipment necessary for river outing.

July 6, 2025 Litter Tally @ Green Brook Litter Trap

The LRWP and SEWA volunteers went out to the litter trap in the Green Brook today, July 6, 2025, to conduct a litter tally after a devastating storm in the area knocked down trees, took out power, and resulted in fatalities. The water was low, with minimal trash flows. Huge thanks to Dr. Johnny and our SEWA International Central Jersey youth partners! Learn more about the litter trap initiative here. And learn more about the LRWP’s litter tally project with SEWA here.

A Half Pence for Your Thoughts

Essay and photos by Joe Mish

Gone are the cows and barbed wire fences along the river, as land use has again changed, the only constant is the presence of the river and even the river has a mind to meander.

A thin round object, consistent with the appearance of a large coin protruded out of the eroded river bank. Closer inspection revealed light blue specs, suggesting copper content. It sure looked and felt like an old coin, its face severely eroded with traces of letters or numbers left to the imagination. Eventually the discovery was tentatively identified as a British half pence, from the mid eighteenth century. Its condition made it practically worthless, except for its historic value as a link to the past life of the river and its surrounding land.

That coin was a reminder of generations past and what their view of the river may have been. Each iteration was defined by the evolving cultural perspective each generation owned. Looking through time at any given layer begs a comparison to current views, and the realization that today’s view is dynamic and changing before our eyes. Though a period may be categorically defined, the transition is the real story, as it gives insight to the collective response under different economic and social pressures.

Each layer of time uncovered, is incomplete without considering the impact of the preceding layer until we arrive at the time the river itself was formed post glacial retreat. As the land sought equilibrium though violent undulations, it changed the gradient of the river’s path and adjusted its character. Critically important were the soil conditions created, which set the stage for a succession of thriving biological communities.

Amazingly, an early life form was discovered near Neshanic Station, where an unrecognized dinosaur tail bone was found and used as a doorstop. Stegomus arcuatus jerseyensis, was a large armored reptile with an alligator-like body, long stout legs, and an opossum-shaped head. Obviously, flora, fauna, climate, which favored this creature went through a series of changes, which no longer supported its existence.

There are ‘moments’ of stability as far as climate, flora, fauna, and associated life forms, and within each seemingly static pause, a culturally driven perspective is applied.

Aptly named, ‘moose-elk’, roamed the wilds of the vast eastern woodlands. This specimen found in New Jersey stands tall at the NJ state museum, in Trenton.

In the days before mills and their dams were built, migratory fisheries were of critical economic importance to those who lived along the river. When the first mill dam was built on the lower Raritan, thus blocking the fish migrations, the upstream residents burned down the mill.

Damming previously unimpeded rivers with grist and textile mills presented an economic opportunity for some, and ended a legacy lifestyle for others. This is an ongoing pattern of change along our rivers.

Amazingly, the gears of Holcomb’s mill, circa 1711, on the South branch of the Raritan, was made of wood! The mill dam has deteriorated and almost vanished.

In the seventeenth century, 1682, Somerset county had placed a bounty on wolves and fox. It is hard to imagine the environment required to sustain a population of wolves in central NJ. Fox were always present, and now coyotes have moved in. Biologists believed the appearance of coyotes was favored by the vast agricultural community and would disappear when the farms were sold off. That conclusion proved to be invalid as the adaptability of coyotes to the changing environment was grossly underestimated.

When the economy shifted from reliance on the rivers, they were still of value to livestock and dairy farmers, providing water for the herds. In one generation, environmental regulations put many farms out of business by restricting the handling of manure and prohibiting cattle from entering streams. Some days the local dairy herd provided a slalom course for my canoe as I wove my way through the herd, brisket deep in the cool water of the South Branch. Today, no cows can be found in or near the river, just remnants of barbed wire fencing embedded deep within the rings of scarred trees once used as fence posts.

Today’s river is centered on recreation as well as providing potable water, serving sewerage treatment plants, and continuing its ancient legacy as a receptacle for refuse. Organizations such as the Central Jersey Stream Team and Lower Raritan Watershed Partnership do their best to gather public support to keep our rivers clean and monitor emerging and legacy pollutants. Looking clean does not equate to the absence of pollutants. Consult the fish consumption warning in your state!

Statements from a Rutgers University president in the 1930s proclaiming the need to clear up the polluted river, have a hollow ring, as 75 years later the same refrain is heard about the same river. Generational priorities change the focus, while looking through the same glass. Industry and profits are replaced with real estate and profits, each contributing different pollutants, many of which live beyond the lifespan of their source.

The high population density in New Jersey stresses the environment and alters the standing cultural view of open space and rivers. The eventual compromise serves as the engine of change.

There is a tenant of wildlife biology referred to as, ‘carrying capacity’, where the local environment can only support a calculated number of a given species before it collapses. Theory exempts humans from this rule based on the belief humans are independence of nature, intelligent and have the technology to overcome nature; a flawed assumption which has often lead to environmental disaster.

Theories aside, peeling back the layers of past perspectives, creates a map for the future, displaying pitfalls, successes, and the realization that science is only true for a moment.

John C. Van Dyke’s words in 1915, preserved in his diary “Notes on a Family” is a valuable Perspective from another time on the that river you see today:

But the river was not always so commonplace. There was a time, and not 300 years ago, when it was unique and thought a wild, wild strea,. no one had been to its head; no one knew how far it travelled. It was then a deeper stream with its waters undimmed by surface drainage from farms. there were no farms. The small open spaces on the meadows were planted with Indian maize; but all the rest of the land was forest. Huge pines grew along the shale cliffs; oak and chestnut and hickory grew in the uplands. There were no towns or bridges or railways or wagon roads. Indian trails ran across the land from river to river, Indian tepees were pitched under the great trees in the meadows, and Indian canoes glanced along the surface of the River. The white man had not yet come, the land was unflayed, the forest and streams were in their pristine beauty. And then……

Author Joe Mish has been running wild in New Jersey since childhood when he found ways to escape his mother’s watchful eyes. He continues to trek the swamps, rivers and thickets seeking to share, with the residents and visitors, all of the state’s natural beauty hidden within full view. To read more of his writing and view more of his gorgeous photographs visit Winter Bear Rising, his wordpress blog. Joe’s series “Nature on the Raritan, Hidden in Plain View” runs monthly as part of the LRWP “Voices of the Watershed” series. Writing and photos used with permission from the author.

Raritan Pathogens Results 7.02.25

By Danielle Bongiovanni and J.M. Meyer

Out of respect for the Fourth of July, this week’s Pathogen Monitoring session occurred on Tuesday, July 2nd instead of a Thursday. 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 Tuesday, July 2, 2025 show Enterococcus bacteria levels exceeding the EPA federal water quality standard of 104 cfu/100mL at two of our monitoring sites this week. Problem sites are indicated by red frowns on the map and chart which includes: Riverside Park (Piscataway) and Rutgers Boathouse (New Brunswick). 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), Ken Buchanan Waterfront Park (Sayreville), Edison Boat Launch (Edison Township), and 2nd Street Park (Perth 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, and runoff from manure storage areas.

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 Fourth of July weekend, make sure to stay safe and wash up after any activities!

Goose droppings await the next rainstorm at the Rutgers Boat House in New Brunswick. The Lower Raritan Watershed Partnership advocates for growing taller and more robust riparian plants to discourage goose activity. — Photo credit Ashley Fritz.
An oily sheen with metallic flakes and brown effluvia floats down Mill Brook near the Edison Boat Basin.
— Photo credit J.M. Meyer.
A fisherman’s catch at Edison Boat Basin includes a ray-finned fish and blue crabs.
— Photo credit Nilesh Bhat.
Nilesh, Ashley, and Vani run the post-testing calibration on the YSI sonde. The YSI sonde is the instrument we use to measure salinity, acidity, oxygen saturation, and other variables. — Photo credit J.M. Meyer.

June 28th Litter trap tally with Sewa

The LRWP and SEWA volunteers went out to the litter trap in the Green Brook on Saturday, June 28th, 2025, to conduct a litter tally. The water was low, with minimal trash flows. Huge thanks to our SEWA International Central Jersey youth partners! Thanks to their efforts, we’ll have much better data on how the litter trap keeps our watershed clean. Learn more about the litter trap initiative here. And learn more about the LRWP’s litter tally project with SEWA here. Below, you’ll find Sewa’s Aasmi Bora describing the litter we picked up, as well as her initial thoughts on why so much litter gets buried in sediment before it reaches the trap.


Guest post by Aasmi Bora

The litter trap is a device that is designed to collect trash and debris before it can end up in larger bodies of water, like the Raritan River. Its main structure is a chute-like mechanism, shown in the picture below, supported by two buoyant pipes (or booms) which keep it afloat.

How effective is our litter trap? To evaluate the effectiveness of the Litter Trap, we conducted an analysis of the waste found both inside and outside the device.

Here’s what we found inside the Litter Trap:

  • 4 small liquor bottles
  • 2 markers
  • 1 small plastic ball
  • 1 basketball
  • 1 fishing bobber
  • 8 plastic bottles
  • 1 plastic eye dropper
  • 3 aluminum cans
  • 1 unopened cigar packet 
  • 1 piece of plastic
  • A large amount of styrofoam (mostly too small to 
  • pick out individually)

In comparison, this is what we found outside of the Litter Trap:

  • 1 toy train
  • 1 teddy bear
  • 7 aluminum cans
  • 2 plastic bottles 
  • 2 plastic wrappers
  • 1 shoe sole
  • 3 pieces of glass
  • 1 piece of fabric
  • 1 shoe sole
  • 1 plastic utensil 
  • 1 base of gumball dispenser 
  • 2 plastic bags
  • 2 tires
  • Many more pieces of plastic
  • More styrofoam 
  • Seat cushion

Why might the Litter Trap be capturing less trash than what is found outside of it?

We began to explore further up the stream to identify possible causes. We noticed how most of the debris was getting caught on tree branches as well as being embedded in the stream bed. Based on these findings, we hypothesized that the shallowness of the stream could be the main culprit. 

During our exploration of the Green Brook, we found a section of the stream with a stronger current than where our litter trap currently rests. We predict that if the litter trap were repositioned in faster current then we would see a better accumulation of debris in the litter trap. As we continue to explore the functions of Litter Trap we aim to find solutions to enhance the design and effectiveness of the device.

Central Jersey Sewa volunteers at Green Brook Litter Trap

This summer, the Lower Raritan Watershed Partnership will partner with the Central Jersey chapter of Sewa International to train the next generation of citizen scientists! The collaboration will focus on the Green Brook litter trap, a project funded through the ‘damages’ assessment of the Cornell Dubilier Electronics site in Plainfield. Together with a handful of science-minded high school students, we will be assessing our toolkit for counting the litter trap’s collections, imagining new ways of protecting our streams, and investigating the point-source of various pollutants in the Green Brook. In a few days, our Sewa volunteers will begin posting their findings.

Ashwin, Nilesh, and Aasmi (L to R) explore the Green Brook for the first time.

This project is part of the Cornell-Dubilier Electronics Natural Resource Damage Assessment and Restoration Plan (NRDAR Plan), and our partners include Dunellen, Green Brook, and the Cornell Dubilier Trustees (New Jersey Department of Environmental Protection, US Fish and Wildlife Service, and National Oceanic Atmospheric Administration).

Stay tuned!

Stay Safe around Harmful Algal Blooms

Summer is the peak season for water-based recreation and relaxation. Unfortunately, it is also the peak season for Harmful Algal Blooms (HABs). Understanding and being able to recognize this natural phenomena is important to keeping you, your pets, and your local watersheds safe.

HABs occur when excess amounts of phosphorus enter a water body, usually by stormwater runoff carrying fertilizers and animal waste, or by faulty septic and sewer systems. Cyanobacteria, also known as blue-green algae, take advantage of the extra nutrients and their populations explode in number.

In 2023, the New Jersey Department of Environmental Protection (NJDEP) recorded HABs at 49 water bodies. Five of the six counties within the Raritan River Basin experienced HABs: Hunterdon, Mercer, Middlesex, Morris, and Somerset Counties.

HABs are associated with fish kills, massive die-offs of aquatic life due to low oxygen levels in the water or due to cyanotoxins released by cyanobacteria. Cyanotoxins can harm humans and pets, and are especially dangerous to children. Health effects in humans include abdominal pain, vomiting, fever, and muscle weakness. If you experience any of these or symptoms resembling an allergic reaction or the flu and believe you may have been exposed to a HAB, seek medical care. Depending on the length and severity of exposure, more serious health complications may include liver and kidney damage, respiratory paralysis, and death.

Protect yourself by staying up to date with advisories issued by the NJDEP. Monitoring occurs via daily flight reports and by local health authorities sampling suspected sites of HABs for laboratory analysis. This data can be interpreted in conjunction with reports from the Lower Raritan Watershed Partnership’s Pathogen Monitoring Program, conducted in partnership with Rutgers Cooperative Extension of Middlesex County and the Interstate Environmental Commission.

Each week, LRWP’s volunteers sample non-bathing beaches along the Raritan River to test for presence of fecal matter and disease causing bacterium, and report findings within 24 hours on the LRWP website, via the Rutgers Raritan River Hydrologic Observatory, and via the regional Community Water Quality Testing program coordinated by the Billion Oyster Project. This data is also uploaded to the US Environmental Protection Agency’s STORET (STOrage and RETrieval) and WQX (Water Quality Exchange) systems used for managing and sharing water quality monitoring data.

Surveillance flight data is color-coded according to µg/L of chlorophyll observed. Higher chlorophyll levels may indicate a HAB and warrant caution. On June 24, 2025 low chlorophyll levels were observed along parts of the Raritan River. Graphic by NJDEP.

There are four Recreational Guidance Advisory Levels depending on the amount of cytotoxins identified in the lab reports. If in doubt about what activities are safe, refrain from drinking, swimming, boating, fishing, or consuming fish products sourced from the water body in question.

Volunteer reporting saves lives! To identify HABs, the NJDEP recommends looking for “a layer of bright bluish‐green or white paint on the water surface. Other evidence of a potential cyanobacterial HAB could be discolored or pea‐green colored water, parallel streaks, or green dots/globs in the water.” If you believe you have spotted one, help keep others safe by reporting it to the NJDEP using their online form.

Water at the site of a HAB may be tinted blue-green, earning cyanobacteria the name “blue-green algae.” Photo by NOAA Great Lakes Environmental Research Laboratory.
The diverse appearances of HABs include cyanobacteria forming globs in the water. Photo by National Park Service.

You can reduce HABs through choices made away from the water, as well. The Lower Raritan Watershed Partnership has tips for reducing fertilizer usage and advocating for proper stormwater management. The NJDEP recommends growing native plants to create a riparian buffer can decrease the amount of rain that flows off your property, picking up pollutants before it enters your waterfront. Minimizing opportunities for stormwater runoff to carry pet waste and fertilizers into waterways minimizes the chance of a HAB occurring.

Summer is the season for swimming, not sickness. Be observant, educate others, and stay safe as you recreate!

HABs are not limited to one season or one type of water body. Whenever you recreating at the beach, a lake, or a river, be mindful of signs like this. Graphic by the NJDEP.

Raritan Pathogens Results 6.26.25

by Danielle Bongiovanni and J.M. Meyer

June flew by, and the last Pathogen Monitoring session of the month occured on Thursday, the 26th. Every Thursday 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 on Friday afternoons. 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, June 26, 2025 show Enterococcus bacteria levels exceeding the EPA federal water quality standard of 104 cfu/100mL at 3 of our monitoring sites this week. Problem sites are indicated by red frowns on the map and chart which includes: Rutgers Boathouse (New Brunswick), Raritan Bay Waterfront Park (South Amboy), 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: Riverside Park (Piscataway), Edison Boat Basin (Edison), and Ken Buchanan Waterfront Park (Sayreville).

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, and runoff from manure storage areas.

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!

The sonde nearly disappears below the water’s surface due to low clarity at Edison Boat Basin. Photo credit: J.M. Meyer.
A Heineken bottle floats amidst debris in the water near the Rutgers Boat House. Photo credit: J.M. Meyer.
Ashley keeps a firm grip on the sonde as she leans over the edge of the dock ramp at Riverside Park. Photo credit: J.M. Meyer.
Aquatic plants like algae thrive in the nutrient-rich waters by Riverside Park. Photo credit: J.M. Meyer.
American herring gulls (Larus smithsonianus)
gather by the edge of the dock at Ken Buchanan Waterfront Park. Photo credit: Ashley Fritz.

From Land to Water: Water health in time of climate change, Teacher Professional Development with the LRWP

What we do on land does not stay on land. The choices we make on what we do on our property can impact the waters nearby as rain and runoff pick-up and move pollutants from their point of origin to our waterways. In a time of climate change when precipitation is highly variable these pollutants are more likely to affect our local and regional water quality.

Join the LRWP for two Teacher Professional Development Workshops, offered in partnership with the New Jersey Climate Change Learning Collaborative and the New Jersey Department of Education.

On both Monday June 23 and Tuesday August 12 we will tour New Brunswick infrastructure and landscape and take a boat trip on the Raritan River to learn more about how we monitor water quality in general and pathogen monitoring more specifically, and about solutions to divert the pollutants from our waterways. These full-day workshops will be followed up with a webinar (August 14th, 4PM EDT) to explore instructional resources related to the Lower Raritan watershed, and water quality monitoring.

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