Surface chlorophyll data were collected on April 29, 2026, while the R/V Data Stream was underway collecting nutrient samples in the Providence and Seekonk River Estuaries. The average chlorophyll concentrations were categorized as good in all areas. The average chlorophyll concentrations were categorized as good to fair over all areas surveyed. Overall, chlorophyll ranged from 1.50 µg/L to 14.60 µg/L with an average of 4.50 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on April 29, 2026, while the R/V Data Stream was underway collecting bacteria samples in the Providence and Seekonk River Estuaries. The average chlorophyll concentrations were categorized as good in all areas. The average chlorophyll concentrations were also categorized as good over all areas surveyed. Overall, chlorophyll ranged from 1.09 µg/L to 3.94 µg/L with an average of 1.96 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on April 15, 2026, while the R/V Data Stream was underway collecting nutrient samples in the Providence and Seekonk River Estuaries. The average chlorophyll concentrations were categorized as fair in all areas. The average chlorophyll concentrations were also categorized as fair over all areas surveyed. Overall, chlorophyll ranged from 1.67 µg/L to 44.92 µg/L with an average of 13.52 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
On April 23rd, 2026, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers; four of these stations were also sampled for enterococci bacteria. In the five days prior to sampling, 0.21” of precipitation was recorded at TF Green. Overall, bacteria counts were higher than during the previous sampling event.
Fecal coliform counts were higher in the Seekonk River, compared to the previous sampling on April 8th (geometric mean of 223 MPN/100 mL compared to 80 MPN/100 mL on 4/8). Fecal coliform counts were also higher in the Providence River, compared to the previous sampling on April 8th (geometric mean of 16 MPN/100 mL compared to 10 MPN/100 mL on 4/8).
Enterococci results had an overall geometric mean of 13 MPN/100 mL. Enterococci counts ranged from <10 MPN/100 mL at most sites to 20 MPN/100 mL at Phillipsdale Landing.
The next scheduled sampling date is May 6th.
Summary of Rhode Island Bacteria Standards for Saltwater Primary Contact and Shellfishing
Geometric mean ≤35 colonies/100 mL All samples ≤104 colonies/100 mL2
Shellfishing
Geometric mean ≤14 MPN/100 mL <10% of samples >49 MPN/100 mL3
NO ENTEROCOCCI CRITERIA
1Fecal coliform primary contact criteria applied only when adequate enterococci data are not available; 2Single sample maximum criterion for determining beach swimming advisories at designated beaches as evaluated by the Rhode Island Department of Health; 3For a three-tube decimal dilution.
On April 8th, 2026, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers; four of these stations were also sampled for enterococci bacteria. In the five days prior to sampling, 0.26” of precipitation was recorded at TF Green. Overall, bacteria counts were slightly lower than during the previous sampling event.
Fecal coliform counts were similar in the Seekonk River, compared to the previous sampling on March 25th (geometric mean of 80 MPN/100 mL compared to 88 MPN/100 mL on 3/25). Fecal coliform counts were lower in the Providence River, compared to the previous sampling on March 25th (geometric mean of 10 MPN/100 mL compared to 25 MPN/100 mL on 3/25).
Enterococci results had an overall geometric mean of 13 MPN/100 mL. Enterococci counts ranged from <10 MPN/100 mL at most sites to 41 MPN/100 mL at Point St. Bridge.
The next scheduled sampling date is April 23rd.
Summary of Rhode Island Bacteria Standards for Saltwater Primary Contact and Shellfishing
Geometric mean ≤35 colonies/100 mL All samples ≤104 colonies/100 mL2
Shellfishing
Geometric mean ≤14 MPN/100 mL <10% of samples >49 MPN/100 mL3
NO ENTEROCOCCI CRITERIA
1Fecal coliform primary contact criteria applied only when adequate enterococci data are not available; 2Single sample maximum criterion for determining beach swimming advisories at designated beaches as evaluated by the Rhode Island Department of Health; 3For a three-tube decimal dilution.
Nutrient samples were collected from seven river stations and seven bay stations on March 18th. In the five days prior to sampling, 1.75” of precipitation were recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN), total dissolved nitrogen (TDN), and dissolved inorganic nitrogen (DIN) were observed at Blackstone River @ Slater Mill (TN = 902 ppb, TDN = 1,210 ppb, DIN = 559 ppb). The lowest TN, TDN and DIN were observed at Pawtuxet River @ Broad St. (TN = 759 ppb, TDN = 657 ppb DIN = 461 ppb).
Among the bay stations sampled, the lowest TN, TDN and DIN were observed Phillipsdale Landing Surface (TN = 999 ppb, TDN = 981 ppb, DIN = 693 ppb). The lowest TN, TDN and DIN were observed at Bullock’s Reach Bottom (TN = 429 ppb, TDN = < 100 ppb DIN = 8.75 ppb).
The next scheduled sampling date is April 1st, 2026.
Nutrient samples were collected from nine river stations on March 4th. In the five days prior to sampling, 0.72” of precipitation were recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN), total dissolved nitrogen (TDN), and dissolved inorganic nitrogen (DIN) were observed at Ten Mile River @ Roger Williams Ave. (TN = 2,550 ppb, TDN = 2,570 ppb, DIN = 2,309.4 ppb). The lowest TN and DIN were observed at Moshassuck River @ Higginson Ave. (TN = 615 ppb, DIN = 509.8 ppb), while the lowest TDN was observed at Moshassuck River @ Footbridge at Mill St. (TDN = 834 ppb).
The next scheduled sampling date is March 18th, 2026.
In celebration of Rhode Island Clean Water Week, the Narragansett Bay Commission (NBC) will offer free public tours of its award-winning Field’s Point Wastewater Treatment Facility in Providence on Saturday, April 18 from 10:00 AM to 1:00 PM.
The tours will include a look at the region’s most sophisticated water quality lab, “touch-a-truck” and “touch-a-boat” with the NBC’s maintenance and research vehicles, photo ops inside a sewer pipe, and other fun activities.
In addition, the NBC will issue certificates of completion to all students who take the tour that may be redeemed for extra credit at school (but students are advised check with their teacher first).
Members of the public can book a tour at 10:00 AM, 10:30 AM, 11:00 AM, 11:30 AM or 12:00 noon by emailing nbcpr@narrabay.com. Spaces are limited. The tour will take approximately 90 minutes.
On March 25th, 2026 twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers; five of these stations were also sampled for enterococci bacteria. In the five days prior to sampling, 1.83 inches of precipitation was recorded at TF Green. This was the first sampling event of 2026.
Fecal coliform counts were higher in the Seekonk River, compared to the Providence River (geometric mean of 88 MPN/100 mL for the Seekonk River compared to 25 MPN/100mL for the Providence River) for sampling conducted on March 25th. The maximum count (150 MPN/100 mL) was measured at the Off BP Outfall sampling location.
Enterococci results had an overall geometric mean of 21 MPN/100 mL. Enterococci counts ranged from <10 MPN/100 mL at Conimicut Point and Point Street Bridge to 52 MPN/100 mL at Phillipsdale Landing.
The next scheduled sampling date is April 8th.
The table below lists the Rhode Island bacteria standards for primary contact and shellfishing established by the Rhode Island Department of Environmental Management (RIDEM). RIDEM defines primary contact as any recreational activities in which there is prolonged and intimate contact with water, involving considerable risk of ingesting water (e.g., swimming, diving, water skiing and surfing). Please note that the RIDEM bacteria standards are provided here for informational purposes only and are not intended to indicate official state compliance with primary contact or shellfishing standards.
Summary of Rhode Island Bacteria Standards for Saltwater Primary Contact and Shellfishing
Geometric mean ≤35 colonies/100 mL All samples ≤104 colonies/100 mL2
Shellfishing
Geometric mean ≤14 MPN/100 mL <10% of samples >49 MPN/100 mL3
NO ENTEROCOCCI CRITERIA
1Fecal coliform primary contact criteria applied only when adequate enterococci data are not available; 2Single sample maximum criterion for determining beach swimming advisories at designated beaches as evaluated by the Rhode Island Department of Health; 3For a three-tube decimal dilution.
After months of waiting and prepping, there’s nothing quite like the feeling of gliding over the water as the world wakes up around you. Our mission this trip? To gather essential nutrients and monitor the health of our water ways. As we cruised along, we collected surface and bottom nutrient samples and watch the surface for signs of life. The first trip of the season isn’t just about science-it’s about reconnecting with nature, honoring the rhythms of our environment, and reminding ourselves why we do what we do. Here’s to many more days on the water this year, chasing nutrients, tracking change, and finding joy in every ripple. We able to catch a picture of a harbor seal basking in the sun right outside Fields point outfall.
