Surface Mapping

Surface chlorophyll data were collected on June 24, 2026, while the R/V Data Stream was underway collecting nutrient samples in the Providence and Seekonk River Estuaries. The chlorophyll concentrations were categorized as good overall. No areas exhibited fair or poor water quality (>10 µg/L and >20 µg/L, respectively). Overall, chlorophyll ranged from 1.08 µg/L to 12.65 µg/L with an average 3.98 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 June 10, 2026, while the R/V Data Stream was underway collecting nutrient samples in the Providence and Seekonk River Estuaries. The chlorophyll concentrations were categorized as fair overall. Only the Seekonk River exhibited poor water quality (>20 µg/L) while the remaining areas sampled exhibited fair water quality (>10 µg/L). Overall, chlorophyll ranged from 2.56 µg/L to 45.25 µg/L with an average 14.57 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 May 20, 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 fair in all areas. The average chlorophyll concentrations were also categorized as fair over all areas surveyed. Overall, chlorophyll ranged from 0.97 µg/L to 120.89 µg/L with an average of 6.97 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 May 7, 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 categorized as good to fair over all areas surveyed. Overall, chlorophyll ranged from 1.60 µg/L to 13.44 µg/L with an average of 4.63 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 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.

Surface chlorophyll data were collected on October 15, 2025, while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuary. 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 0.64 µg/L to 3.60 µg/L with an average of 1.57 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 October 1, 2025, while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuary. The average chlorophyll concentrations were categorized as fair in the Seekonk River, and as good in all other areas. The average chlorophyll concentrations were categorized as good over all areas surveyed. Overall, chlorophyll ranged from 2.07 µg/L to 10.16 µg/L with an average of 4.94 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 September 17, 2025, while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuary. The average chlorophyll concentrations were categorized as good in the Northern Providence River Channel and the Seekonk River, and as fair in all other areas. The average chlorophyll concentrations were categorized as fair over all areas surveyed. Overall, chlorophyll ranged from 0.98 µg/L to 20.49 µg/L with an average of 6.73 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.