Today a new MET Sensor Assembly was installed on the recently deployed Bullocks Reach Buoy. The assembly includes a weather station that can monitor wind speed, humidity, air pressure, and temperature. The buoy was deployed on May 14th and staff have been diligently working to get the buoy up and running for the 2024 Fixed Site Monitoring Season.
Nutrient samples were collected from seven river stations on May 15th and seven bay stations on May 14th. In the five days prior to sampling, there were 0.1 inches of precipitation recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN) and dissolved inorganic nitrogen (DIN) concentrations were observed at Pawtuxet River @ Broad St. (TN = 855 ppb, DIN = 687 ppb), while the highest total dissolved nitrogen (TDN) were observed at Moshassuck River @ Footbridge at Mill St. (TDN = 907 ppb). The lowest TN, TDN, and DIN were observed at Moshassuck River @ Higginson Ave. (TN = 525 ppb, TDN = 530 ppb, DIN = 308 ppb).
Among the bay stations sampled, the highest surface TN were observed at India Point Park (TN = 926 ppb), while the highest surface TDN and DIN were observed at Phillipsdale Landing (TDN = 804 ppb, DIN = 620 ppb). The lowest surface TN and TDN were observed at Conimicut Point (TN = 396 ppb, TDN = 160 ppb), while the lowest surface DIN was at Bullock Reach Buoy (DIN = 13 ppb). Chlorophyll a concentrations at the surface bay stations averaged 9.45 μg/L overall with a maximum of 27.95 μg/L at Pomham Rocks.
The next scheduled sampling date is May 29, 2024.
Phytoplankton samples were collected on May 1, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a cold and breeze day on Narragansett Bay with cloudy conditions. The qualitative tow net sample had a long filtration time, and the filtrate was a reddish brown and slightly cloudy.
The analysis of the quantitative whole water sample revealed a total of 4,006,000 cells per Liter. The micro flagellates were found at 24,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 1,646,000 cells/L. Other representative genera include Thalassiosira spp., Leptocylindrus spp., and Chaetoceros spp. This week’s featured image is Eucampia spp. (200x phase contrast), a type of diatomic phytoplankton that is often found in the North Atlantic Ocean. This genus is often found in a curved form and in helical chains. This diatom is yellow-brown in color with numerous green chloroplasts.
Nutrient samples were collected from thirteen river stations on May 1st. In the five days prior to sampling, there were 0.13 inches of precipitation recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN), total dissolved nitrogen (TDN), and dissolved inorganic nitrogen (DIN) concentrations were observed at Ten Mile River @ Central Ave (TN = 1,340 ppb, TDN = 1,260 ppb, DIN = 946.2 ppb). The lowest TN and TDN were observed at Moshassuck River @ Higginson (TN = 530 ppb, TDN = 436 ppb, each being duplicate samples taken at the site). The lowest DIN were observed at Coles River @ Milford Rd. (DIN = 58 ppb).
Among the bay stations sampled, the highest surface TN, TDN, and DIN were observed at Phillipsdale Landing (TN = 1,000 ppb, TDN = 836 ppb, DIN = 663 ppb). The lowest surface TN were observed at Conimicut Point (TN = 544 ppb), while lowest surface TDN and DIN were observed at Edgewood Shoal (TDN = 124 ppb, DIN = 17 ppb). Chlorophyll a concentrations at the surface bay stations averaged 19.62 μg/L overall with a maximum of 35.12 μg/L at the Bullock Reach Buoy.
The next scheduled sampling date is May 14, 2024.
Phillipsdale Landing
Sondes were swapped this week on the morning of July 23rd. Overall, water quality at Phillipsdale Landing was good to fair this week. Weather conditions included sporadic rain events, with 0.46 inches of precipitation recorded at T.F. Green. The Blackstone River flow fluctuate through the week in response to rain, while remaining below the 19-year daily median. Surface salinity averaged 20.9 ppt and ranged from 0.0 ppt to 25.4 ppt. At the bottom, salinity averaged 23.3 ppt and ranged from 14.7 ppt to 27.4 ppt. Temperatures continued to increase this week, averaging 24.6°C at the surface and ranging 23.6°C – 26.2°C. At the bottom, temperatures averaged 23.9°C and ranged 22.3°C – 25.6°C.
Dissolved oxygen (DO) at Phillipsdale Landing dropped below the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO average 5.7 mg/L and ranged from 1.9 mg/L to 14.1 mg/L. Bottom DO concentrations averaged 3.4 mg/L and ranged from 0.7 mg/L to 9.5 mg/L. The longest period of hypoxic conditions (15 hours, 15 minutes) occurred at the bottom depth between the afternoons of July 24th and July 25th. During this period, bottom DO averaged around 2.28 mg/L. Chlorophyll readings decreased from last week, averaging 23.8 µg/L at the surface and 18.3 µg/L at the bottom. Maximum chlorophyll at the surface reached 132.3 µg/L on the afternoon of July 25th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Overall, water quality was good to fair at Bullock Reach this week. Salinity averaged 25.6 ppt, 27.4 ppt, and 29.2 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 23.4 – 27.5 ppt, mid salinity ranged 13.3 – 29.3 ppt, and bottom salinity ranged 27.1 – 30.1 ppt. Surface temperature averaged 24.2°C and ranged from 22.9°C to 26.1°C. Mid temperatures averaged 23.4°C and ranged from 21.2°C to 25.8°C. Bottom temperatures averaged 21.4°C and ranged from 19.9°C to 24.1°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week at the surface. Middle and Bottom DO dropped below the hypoxia threshold frequently throughout the week. Surface DO averaged 6.5 mg/L and ranged 3.7 – 10.3 mg/L. In the mid waters, DO averaged 4.6 mg/L and ranged 2.7 – 8.9 mg/L. At the bottom, DO averaged 3.1 mg/L and ranged 1.9 – 4.9 mg/L.
The longest period of hypoxic conditions (1 day, 2 hours, and 45 minutes) occurred at the bottom depth between the morning of July 22nd and the afternoon of July 23rd. During this period, bottom DO averaged around 2.44 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the week. Readings averaged 12.7 µg/L at the surface, 9.5 µg/L at mid-depth, and 5.6 µg/L at the bottom. The maximum surface chlorophyll was 42.4 µg/L on the morning of July 28th.
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was fair this week. Weather conditions were dry, with only 0.79 inches recorded at T.F. Green. The Blackstone River flow continued an overall decreasing trend through the week. Surface salinity averaged 10.6 ppt and ranged from 2.6 ppt to 22.3 ppt. At the bottom, salinity averaged 20.3 ppt and ranged from 4.9 ppt to 27.3 ppt. Temperatures continued to increase this week, averaging 27.0°C at the surface and ranging 23.5°C – 30.6°C. At the bottom, temperatures averaged 24.5°C and ranged 21.3°C – 29.0°C.
Dissolved oxygen (DO) at Phillipsdale Landing dropped below the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO average 9.1 mg/L and ranged from 0.7 mg/L to 17.3 mg/L. Bottom DO concentrations averaged 2.6 mg/L and ranged from 0.6 mg/L to 9.7 mg/L. The longest period of hypoxic conditions (22 hours) occurred from mid-day on July 18th to the morning of July 19th. During this period, bottom DO averaged around 1.54 mg/L. Chlorophyll readings decreased from last week, averaging 50.9 µg/L at the surface and 28.1 µg/L at the bottom. Maximum chlorophyll at the surface reached 329.3 µg/L on the morning of July 17th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Sondes were swapped this week on the morning of July 16th. Overall, water quality was good to fair at Bullock Reach this week. Salinity averaged 23.3 ppt, 26.1 ppt, and 29.5 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 20.0 – 26.4 ppt, mid salinity ranged 23.4 – 29.3 ppt, and bottom salinity ranged 27.87 – 30.7 ppt. Surface temperature averaged 26.6°C and ranged from 24.3°C to 28.9°C. Mid temperatures averaged 25.2°C and ranged from 21.4°C to 27.8°C. Bottom temperatures averaged 21.0°C and ranged from 19.1°C to 22.7°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week at the surface. Middle and Bottom DO dropped below the hypoxia threshold frequently throughout the week. Surface DO averaged 7.2 mg/L and ranged 4.4 – 9.3 mg/L. In the mid waters, DO averaged 4.8 mg/L and ranged 1.6 – 7.8 mg/L. At the bottom, DO averaged 2.2 mg/L and ranged 1.3 – 3.6 mg/L. The longest period of hypoxic conditions (2 days and 7 hours) occurred at the bottom depth between the night of July 16th and the morning of July 19th. During this period, bottom DO averaged around 1.85 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the week. Readings averaged 11.2 µg/L at the surface, 13.4 µg/L at mid-depth, and 4.1 µg/L at the bottom. The maximum surface chlorophyll was 28.5 µg/L on the morning of July 15th.
Phillipsdale Landing
Sondes were swapped this week on the morning of July 9th. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were dry, with only 0.48 inches on July 13th, recorded at T.F. Green. The Blackstone River flow declined this week, dropping below the 19-year daily median mid-week. Surface salinity averaged 9.0 ppt and ranged from 2.6 ppt to 18.0 ppt. At the bottom, salinity averaged 17.7 ppt and ranged from 5.1 ppt to 25.1 ppt. Temperatures continued to increase this week, averaging 26.8°C at the surface and ranging 24.8°C – 30.6°C. At the bottom, temperatures averaged 24.8°C and ranged 22.0°C – 28.7°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at the surface throughout the week, while DO at the bottom waters remained below the hypoxic threshold for most of the week. Surface DO average 10.1 mg/L and ranged from 4.5 mg/L to 19.1 mg/L. Bottom DO concentrations averaged 4.1 mg/L and ranged from 0.8 mg/L to 13.3 mg/L. The longest period of hypoxic conditions (10 hours, 45 minutes) occurred at the bottom depth from the morning to afternoon of July 14th. During this period, bottom DO averaged around 1.68 mg/L. Chlorophyll readings rose from last week, averaging 85.8 µg/L at the surface and 46.4 µg/L at the bottom. Maximum chlorophyll at the surface reached 261.8 µg/L on the morning of July 9th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Overall, water quality was good at Bullock Reach this week. Salinity averaged 23.4 ppt, 25.9 ppt, and 28.8 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 19.9 – 26.2 ppt, mid salinity ranged 23.2 -28.2 ppt, and bottom salinity ranged 26.3 – 30.4 ppt. Surface temperature averaged 25.7°C and ranged from 23.6°C to 27.9°C. Mid temperatures averaged 24.7°C and ranged from 20.9°C to 26.2°C. Bottom temperatures averaged 21.6°C and ranged from 19.3°C to 25.3°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at the surface and middle depths throughout the week. Bottom DO dropped below the threshold, with the longest hypoxic period (11 hours and 15 minutes) occurring between the night of July 13th and the morning of July 14th.
During this period, the bottom DO averaged around 2.52 mg/L. Surface DO averaged 7.3 mg/L and ranged 4.5 – 12.0 mg/L. In the mid waters, DO averaged 5.9 mg/L and ranged 3.2 – 8.2 mg/L. At the bottom, DO averaged 3.7 mg/L and ranged 2.1 – 6.5 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the week. Readings averaged 18.4 µg/L at the surface, 15.0 µg/L at mid-depth, and 4.1 µg/L at the bottom. The maximum surface chlorophyll was 52.8 µg/L on the afternoon of July 8th.
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was good this week. Weather conditions included sporadic rain events, with 0.83 inches of precipitation recorded at T.F. Green. The Blackstone River flow fluctuate through the week in response to sporadic rain events. salinity averaged 13.9 ppt and ranged from 2.9 ppt to 22.8 ppt. At the bottom, salinity averaged 21.1 ppt and ranged from 7.2 ppt to 28.2 ppt. Temperatures continued to increase this week, averaging 25.6°C at the surface and ranging 23.3°C – 28.5°C. At the bottom, temperatures averaged 22.3°C and ranged 19.7°C – 24.5°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at the surface throughout the week. DO sporadically dropped below the threshold in the bottom waters. Surface DO average 8.7 mg/L and ranged from 3.4 mg/L to 18.4 mg/L. Bottom DO concentrations averaged 5.2 mg/L and ranged from 2.8 mg/L to 11.1 mg/L. The longest period of hypoxic conditions (1 hour) occurred in the afternoon of July 2nd. During this period, bottom DO averaged around 2.84 mg/L. Chlorophyll readings rose from last week, averaging 63.5 µg/L at the surface and 33.4 µg/L at the bottom. Maximum chlorophyll at the surface reached 125.4 µg/L on the night of July 4th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Sondes were swapped this week on the morning of July 2nd. Overall, water quality was good at Bullock Reach this week. Salinity averaged 24.5 ppt, 26.7 ppt, and 28.8 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 20.8 – 26.6 ppt, mid salinity ranged 22.8 – 30.3 ppt, and bottom salinity ranged 26.9 – 30.5 ppt. Surface temperature averaged 22.9°C and ranged from 21.2°C to 25.3°C. Mid temperatures averaged 22.0°C and ranged from 18.7°C to 23.8°C. Bottom temperatures averaged 20.0°C and ranged from 17.8°C to 23.0°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at all depths throughout the week. Surface DO averaged 7.5 mg/L and ranged 4.8 – 12.5 mg/L. In the mid waters, DO averaged 6.3 mg/L and ranged 4.1 – 8.4 mg/L. At the bottom, DO averaged 4.7 mg/L and ranged 3.3 – 6.9 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the week. Readings averaged 16.3 µg/L at the surface, 13.0 µg/L at mid-depth, and 4.9 µg/L at the bottom. The maximum surface chlorophyll was 48.3 µg/L on the afternoon of July 2nd.
Phillipsdale Landing
Sondes were swapped this week on the morning of June 25th. Overall, water quality at Phillipsdale Landing was fair this week. Weather conditions included sporadic rain events, with 2.17 inches of precipitation recorded at T.F. Green. The Blackstone River flow fluctuate through the week in response to rain, while still remaining above the 19-year daily median. Surface salinity averaged 9.1 ppt and ranged from 2.6 ppt to 20.3 ppt. At the bottom, salinity averaged 18.6 ppt and ranged from 5.4 ppt to 28.1 ppt. Temperatures continued to increase this week, averaging 25.1°C at the surface and ranging 22.0°C – 27.8°C. At the bottom, temperatures averaged 22.1°C and ranged 19.6°C – 24.7°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at the surface throughout the week. DO sporadically dropped below the threshold in the bottom waters. Surface DO average 7.44 mg/L and ranged from 3.99 mg/L to 11.35 mg/L. Bottom DO concentrations averaged 4.5 mg/L and ranged from 2.2 mg/L to 10.3 mg/L. Chlorophyll readings dropped slightly from last week, averaging 28.64 µg/L at the surface and 19.9 µg/L at the bottom. Maximum chlorophyll at the surface reached 81.2 µg/L on the morning of June 30th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Overall, water quality was good at Bullock Reach this week. Salinity averaged 24.7 ppt, 28.2 ppt, and 27.3 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 20.9 – 27.2 ppt, mid salinity ranged 25.1 – 29.8 ppt, and bottom salinity ranged 23.1 – 30.3 ppt. Surface temperature averaged 22.5°C and ranged from 21.1°C to 25.1°C. Mid temperatures averaged 19.8°C and ranged from 17.8°C to 22.2°C. Bottom temperatures averaged 21.5°C and ranged from 18.5°C to 23.3°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at all depths throughout the week. Surface DO averaged 7.5 mg/L and ranged 5.3 – 10.9 mg/L. In the mid waters, DO averaged 4.8 mg/L and ranged 3.1 – 6.8 mg/L. At the bottom, DO averaged 6.2 mg/L and ranged 4.3– 8.8 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the month. Readings averaged 17.1 µg/L at the surface, 8.2 µg/L at mid-depth, and 18.3 µg/L at the bottom. The maximum surface chlorophyll was 51.1 µg/L on the afternoon of June 28th.
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was fair this week. Weather conditions included sporadic rain events, with 2.22 inches of precipitation recorded at T.F. Green. The Blackstone River flow fluctuate through the week in response to rain, while still remaining above the 19-year daily median. Surface salinity averaged 9.4 ppt and ranged from 2.5 ppt to 19.8 ppt. At the bottom, salinity averaged 18.9 ppt and ranged from 5.9 ppt to 26.0 ppt. Temperatures continued to increase this week, averaging 23.9°C at the surface and ranging 20.6°C – 28.3°C. At the bottom, temperatures averaged 21.4°C and ranged 18.3°C – 25.5°C.
Dissolved oxygen (DO) at Phillipsdale Landing has remained high at the surface, with only a few dropped readings below the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO was lower than the previous week, averaging 8.3 mg/L and ranging 2.65 mg/L to 14.1 mg/L. Bottom DO concentrations dropped below the hypoxia level (i.e., DO <2.9 mg/L) briefly this week, averaging 4.2 mg/L and ranged from 2.0 mg/L to 10.0 mg/L. Chlorophyll readings have risen from last week, averaging 35.54 µg/L at the surface and 27.7 µg/L at the bottom. Maximum chlorophyll at the surface reached 98.2 µg/L on the night of June 21st. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Sondes were swapped this week on the morning of June 18th. Overall, water quality was good at Bullock Reach this week. Salinity averaged 23.9 ppt, 28.0 ppt, and 24.0 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 19.3 – 27.0 ppt, mid salinity ranged 25.1 – 30.0 ppt, and bottom salinity ranged 0.0 – 29.9 ppt. Surface temperature averaged 23.3°C and ranged from 19.8°C to 26.1°C. Mid temperatures averaged 18.8°C and ranged from 16.4°C to 21.9°C. Bottom temperatures averaged 21.5°C and ranged from 15.7°C to 25.0°C.
DO at Bullock Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) at all depths throughout the week. Surface DO averaged 8.1 mg/L and ranged 5.7 – 11.6 mg/L. In the mid waters, DO averaged 5.0 mg/L and ranged 3.4 – 9.0 mg/L. At the bottom, DO averaged 6.6 mg/L and ranged 2.9– 9.4 mg/L. Chlorophyll readings ranged from low to elevated, with evidence of moderate phytoplankton blooms occurring throughout the month. Readings averaged 15.8 µg/L at the surface, 8.4 µg/L at mid-depth, and 11.2 µg/L at the bottom. The maximum surface chlorophyll was 47.9 µg/L on the morning of June 23rd.