Historical News
Week of August 8 – 14, 2021
Water Column Profiles
Water column profiles were conducted at six locations in the Providence River using a Seabird profiling instrument on August 11, 2021. Conditions leading up to the survey were dry, with trace amounts of rainfall recorded at T.F. Green over the five days prior to the survey. Strong stratification was observed at Conimicut Point.
Water column salinity was greatest at Conimicut Point, ranging from 26 psu in surface waters to 31 psu in bottom waters. Lowest surface salinity (23 psu) occurred at India Point Park, while lowest bottom salinity (25 psu) occurred at Pawtuxet Cove. The coolest water column temperatures occurred at Conimicut Point, ranging 20.1°C – 22.9°C. The warmest surface water temperature (24.1°C) occurred at Edgewood Yacht Club, while the greatest bottom temperature (23.1°C) occurred at Pawtuxet Cove.
Dissolved oxygen (DO) concentrations were low this week, with hypoxic conditions (e.g., DO <2.9 mg/L) observed at four sites. The sites with DO levels remaining above this threshold were India Point Park (minimum value: 3.0 mg/L) and Pawtuxet Cove (minimum value 4.4 mg/L). Greatest DO values occurred in surface waters at these sites. The site with the lowest DO in bottom waters was Edgewood Yacht Club, with values of 0.2 mg/L in the bottom 0.75 meters of the water column. Maximum fluorescence this week was observed at Edgewood Yacht Club at mid-depth. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
Week of August 1 – 7, 2021
Water Column Profiles
Water column profiles were conducted at eight locations in the Seekonk and Providence Rivers using a Seabird profiling instrument on August 4, 2021. Conditions leading up to the survey were dry, with only trace amounts of rainfall recorded at T.F. Green over the five days prior to the survey. Some evidence of stratification was present at most sites, though the Point St. Bridge site appeared relatively well-mixed.
Water column salinity was greatest at Conimicut Point, ranging from 25 psu in surface waters to 31 psu in bottom waters. Lowest surface salinity was 5 psu at Phillipsdale Landing, while lowest bottom salinity was 24 psu at Point St. Bridge. Water temperatures were warmest at Point St. Bridge, measuring 24.4°C in surface waters and 23.9°C in bottom waters. The coolest surface temperature (22.1°C) occurred at Phillipsdale Landing, while the lowest bottom temperature (20.0°C) occurred at Conimicut Point.
Dissolved oxygen (DO) concentrations were low this week, with hypoxic conditions (e.g., DO <2.9 mg/L) observed at six sites. The sites with DO levels remaining above this threshold were Point St. Bridge (range: 3.9 – 4.9 mg/L) and Pawtuxet Cove (range: 3.2 – 11.2 mg/L); highest DO values occurred in surface waters at these sites. The site with the lowest DO in bottom waters was Edgewood Yacht Club, with a minimum value of 0.7 mg/L at a depth of 4.75 m. Maximum fluorescence this week was observed in near-surface waters at Edgewood Yacht Club. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
Water column salinity was greatest at Conimicut Point, ranging from 25 psu in surface waters to 31 psu in bottom waters. Lowest surface salinity was 5 psu at Phillipsdale Landing, while lowest bottom salinity was 24 psu at Point St. Bridge. Water temperatures were warmest at Point St. Bridge, measuring 24.4°C in surface waters and 23.9°C in bottom waters. The coolest surface temperature (22.1°C) occurred at Phillipsdale Landing, while the lowest bottom temperature (20.0°C) occurred at Conimicut Point.
Dissolved oxygen (DO) concentrations were low this week, with hypoxic conditions (e.g., DO <2.9 mg/L) observed at six sites. The sites with DO levels remaining above this threshold were Point St. Bridge (range: 3.9 – 4.9 mg/L) and Pawtuxet Cove (range: 3.2 – 11.2 mg/L); highest DO values occurred in surface waters at these sites. The site with the lowest DO in bottom waters was Edgewood Yacht Club, with a minimum value of 0.7 mg/L at a depth of 4.75 m. Maximum fluorescence this week was observed in near-surface waters at Edgewood Yacht Club. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
Week of July 25 - 31, 2021
Water Column Profiles
Water column profiles were conducted at six locations in the Providence River using a Seabird profiling instrument on July 28, 2021. Conditions leading up to the survey included light rainfall recorded at T.F. Green over the five days prior, totaling 0.24 inches.
The lowest salinities this week were observed at Pawtuxet Cove, ranging from 16 psu at the surface to 24 psu at the bottom. The highest salinities in surface waters were observed at India Point Park and Edgewood Yacht Club, at 23 psu; the highest bottom salinities (30 psu) were observed at Bullock Reach and Conimicut Point. Surface temperatures ranged from 22.5°C at Pomham Rocks to 23.4°C at Conimicut Point and Bullock Reach. Bottom temperatures were coolest (~20°C) at Conimicut Point and warmest (~23°C) at Pawtuxet Cove.
Dissolved oxygen (DO) concentrations were low this week, with hypoxic conditions (e.g., DO <2.9 mg/L) observed at almost all sites. The only site with DO levels remaining above this threshold was Conimicut Point, where DO ranged 3.5-6.2 mg/L, with the highest values near the surface. The site with the lowest DO was Pawtuxet Cove, where hypoxic conditions were observed in the bottom 1 m, reaching a minimum of 1.4 mg/L. Maximum fluorescence this week was observed in near-surface waters at Conimicut Point. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
Week of July 18 - 24, 2021
Water Column Profiles
Water column profiles were conducted at eight locations in the Providence and Seekonk Rivers using a Seabird profiling instrument on July 21, 2021. Conditions leading up to the survey included a large rainstorm four days prior (1.52 inches) and light rain totaling 0.11 inches over the two to three days prior, according to data from T.F. Green. Field staff noted a strong current during the survey.
The lowest salinities this week were observed at Phillipsdale Landing, the site furthest from the main-body of the Bay and near several major freshwater sources. At this site, salinity was less than 5 psu from the surface to 4 m depth. The maximum salinity at the bottom at Phillipsdale was just 19 psu. Salinities were highest at Bullock Reach, where surface waters measured 21 psu and bottom waters measured 30 psu (note Conimicut Point bottom water salinity was similarly high). Surface temperatures ranged from 22°C at Edgewood Yacht Club, India Point Park, and Pomham Rocks to 24°C at Conimicut Point, Bullock Reach, and Point St. Bridge. Bottom temperatures were coolest (19°C) at Pomham Rocks and warmest (23°C) at Point St. Bridge.
Dissolved oxygen (DO) concentrations were low this week, with hypoxic conditions (e.g., DO <2.9 mg/L) observed at almost all sites. The only site with DO levels remaining above this threshold was Phillipsdale Landing, thanks to the heavy influx of freshwater flows from area rivers following rain events. DO at Phillipsdale was between 5 and 6 mg/L through the full water column. The site with the lowest DO this week was Edgewood Yacht Club, where hypoxic conditions were observed from 1.75 m and deeper, hitting a minimum of <0.1 mg/L at the bottom. Maximum fluorescence this week was observed in surface waters at Conimicut Point and Bullock Reach. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
Week of July 11 - 17, 2021
Water Column Profiles
Water column profiles were conducted at six locations in the Providence River using a Seabird profiling instrument on July 15, 2021. Profiles from two sites (Edgewood Yacht Club and Edgewood Shoal) show signs of sediment interference, were deemed problematic, and are excluded from analysis. Conditions leading up to the survey included a major rainstorm six days prior (2.05 inches) and a moderate storm (0.63 inches) three days prior, according to data from T.F. Green.
The lowest salinities this week were observed at Pawtuxet Cove, with 1.9 psu at the surface and 20.0 psu in bottom waters. This site is near the major freshwater source of the Pawtuxet River, likely flowing at high rates following recent rain events. The highest salinities were observed at the sites closest to the main-body of the Bay, like Conimicut Point where salinity ranged from approximately 15.0 psu at the surface to 30.4 psu at the bottom. Bottom salinities at Bullock Reach were similar. Surface temperatures ranged from 21°C at Pomham Rocks to 23°C at Conimicut Point and Bullock Reach. Bottom temperatures ranged from 19°C at Conimicut Point and Bullock Reach to 21°C at Pawtuxet Cove.
Dissolved oxygen (DO) concentrations were variable this week. Hypoxic conditions (e.g., DO <2.9 mg/L) were observed in the bottom waters of Pomham Rocks and mid-depth at Bullock Reach and Conimicut Point. The minimum DO was 1.9 mg/L, in Pomham Rocks bottom waters. The highest DO concentrations were observed in surface waters at Bullock Reach and Conimicut Point, at 7 mg/L. Please note that due to a quality control issue, numerical fluorescence data are not posted at this time.
