Water Column Profiles

Water column profiles were conducted at eight locations in the Providence and Seekonk River estuaries on May 31, 2023 using a Seabird Electronics profiler. There was no precipitation recorded at T.F. Green in the three days leading up to the survey. All sites exhibited strong density stratification except for Pomham Rocks, which was moderately stratified.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 3.01 mg/L in the bottom waters of Edgewood Shoal. Fluorescence was fairly low this week, ranging from 1.80 to 11.9 mg/m³.

Water column profiles were conducted at eight locations in the Providence and Seekonk River estuaries on May 24, 2023 using a Seabird Electronics profiler. In the three days leading up to the survey, there were 0.02 inches of precipitation recorded at T.F. Green. Despite the lack of recent rainfall, all sites exhibited strong density stratification except for Point St Bridge, which exhibited moderate density stratification.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 4.56 mg/L in the bottom waters of Phillipsdale landing. Fluorescence was low to moderately elevated this week, with the highest value (25.3 mg/m³) observed at Pomham Rocks.

Water column profiles were conducted at seven locations in the Providence and Seekonk River estuaries on May 18, 2023 using a Seabird Electronics profiler. There was no precipitation recorded at T.F. Green in the three days leading up to the survey. Despite the lack of recent rainfall, Phillipsdale Landing still showed strong density stratification and Bullock Reach Buoy showed moderate density stratification; all other sites were well mixed to weakly stratified.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 6.62 mg/L near the middle of the water column at Pomham Rocks. Fluorescence was low to moderately elevated, with the highest value (10.09 mg/m3) observed 2.5 m deep at Conimicut Point West.

Water column profiles were conducted at eight locations in the Providence and Seekonk River estuaries on May 3, 2023 using a Seabird Electronics profiler. There were 2.68 inches of precipitation recorded at T.F. Green in the three days leading up to the survey, almost all from a large rain event on April 30th. ​ Evidence of moderate density stratification was observed at Edgewood Yacht Club; all other sites had strong density stratification.

Surface salinities ranged from 0.55 psu at Phillipsdale Landing to 16.9 psu at Edgewood Yacht Club; bottom salinities ranged from 21.1 psu at Phillipsdale Landing to 29.9 psu at Conimicut Point West. Surface temperatures ranged from 12.4°C at Pawtuxet Cove to 13.7°C at Bullock Reach Buoy, while bottom temperatures ranged from 10.5°C at Conimicut Point West to 12.9°C at Pawtuxet Cove.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 5.05 mg/L near the surface (1.5 m deep) at Pomham Rocks. Fluorescence was low this week, with the highest value (5.38 mg/m3) observed 1.75 m deep at Bullock Reach Buoy.

Water column profiles were conducted at seven locations in the Providence and Seekonk River estuaries on April 19, 2023 using a Seabird Electronics profiler. There were 0.17 inches of precipitation recorded at T.F. Green in the three days leading up to the survey. Evidence of strong density stratification was observed at Phillipsdale Landing, Pomham Rocks, and Pawtuxet Cove. Evidence of moderate density stratification was observed at India Point Park, Conimicut Point West, and Bullock Reach Buoy, while Edgewood Yacht Club showed signs of being well mixed.

Surface salinities ranged from 12.5 psu at Phillipsdale Landing to 25.9 psu at Conimicut Point West; bottom salinities ranged from 24.4 psu at Edgewood Yacht Club to 30.2 psu at Conimicut Point West. Surface temperatures ranged 10.6°C at India Point Park to 12.5°C at Pawtuxet Cove, while bottom temperatures ranged from 8.4°C at Pomham Rocks to 11.3°C at Pawtuxet Cove.

Dissolved oxygen (DO) conditions were below the hypoxia threshold (2.9 mg/L) throughout the water column at Edgewood Yacht Club this week, averaging 2.6 mg/L. All other sites remained above the hypoxia threshold. Fluorescence was low to moderately elevated, with the highest value (8.42 mg/m3) observed near the middle of the water column at Pawtuxet Cove.

Water column profiles were conducted at six locations in the Providence and Seekonk River Estuaries on April 5, 2023 using a Seabird Electronics profiler. There was no precipitation recorded at T.F. Green in the three days leading up to the survey. Evidence of strong density stratification was observed at Phillipsdale Landing, Edgewood Shoal, and Pawtuxet Cove; all other sites showed signs of moderate density stratification.

Surface salinities ranged from 4.3 psu at Pawtuxet Cove to 22.1 psu at Pomham Rocks; bottom salinities ranged from 23.9 psu at Pawtuxet Cove to 28.0 psu at Pomham Rocks. Surface temperatures ranged 9.0°C at India Point Park to 10.8°C at Pawtuxet Cove, while bottom temperatures ranged from 7.3°C at Pomham Rocks to 9.0°C at Pawtuxet Cove.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 8.5 mg/L in the bottom waters at Pawtuxet Cove. Fluorescence was fairly low, with the highest value (5.05 mg/m3) observed near the middle of the water column (3.25 meters deep) at Pomham Rocks.

Water column profiles were conducted at seven locations in the Providence and Seekonk River Estuaries on March 22, 2023 using a Seabird Electronics profiler. There was no precipitation recorded at T.F. Green in the three days leading up to the survey. Evidence of strong density stratification was observed at sites near the middle of the bay (Pomham Rocks, Edgewood Yacht Club, and Pawtuxet Cove), with sites to the north and south of these showing signs of weak to moderate density stratification.

Surface salinities ranged from 3.2 psu at Pawtuxet Cove to 24.3 psu at Bullock Reach Buoy; bottom salinities ranged from 22.8 psu at Phillipsdale Landing to 28.8 psu at Conimicut Point. Surface temperatures ranged from 6.3°C at India Point Park to 7.2°C at Pawtuxet Cove, while bottom temperatures ranged from 5.8°C at Conimicut Point to 6.7°C at Pawtuxet Cove.

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 9.9 mg/L in the bottom waters at Edgewood Yacht Club. Fluorescence was higher than the previous survey, with the highest value (22.98 mg/m3) observed near the surface at India Point Park but many other areas remaining relatively low. ​

Water column profiles were conducted at seven locations in the Providence River Estuary on February 22, 2023 using a Seabird Electronics profiler. In the three days leading up to the survey, 0.17 inches of rainfall were recorded at T.F. Green. Evidence of moderate density stratification was observed at most sites this week, with Pawtuxet Cove showing signs of strong stratification and Bullock Reach and Edgewood Shoals showing signs of weak stratification.

Surface salinities ranged from 20 psu at Pawtuxet Cove to 26 psu at Bullock Reach Buoy and Edgewood Shoal. Bottom salinities ranged from 27 psu at Pawtuxet Cove to 30 psu at Conimicut Point. The coolest water temperatures ranged from 5.4°C at the surface of Conimicut Point to 5.7°C at bottom of India Point Park. The warmest surface water temperature (5.9°C) was observed at Pawtuxet Cove and Edgewood Shoal, while the warmest bottom temperature (6.0°C) was observed at Pawtuxet Cove and Conimicut Point. 

Dissolved oxygen (DO) conditions remained above the hypoxia threshold (2.9 mg/L) at all sites this week; the lowest DO observed was approximately 9.4 mg/L in the bottom waters at India Point Park. Overall, fluorescence was generally low, with the highest value (9.23 mg/m³) observed near the middle of the water column (4.0 meters deep) at Edgewood Yacht Club. Please note numerical fluorescence data were not posted from 2020 to 2021 due to a QC issue. This issue has been resolved and fluorescence data from 2020 and 2021 will be backfilled.