Historical News
May 14, 2024
Phytoplankton Sampling
Phytoplankton samples were collected on May 14, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a beautiful day on Narragansett Bay with partly cloudy conditions and a slight breeze. Sonde data revealed the surface water temperature was 14.67°C, salinity was 21.36 psu, and chlorophyll a was 8.77 ug/L. Secchi disk water clarity was 3.4 m. The qualitative tow net sample had a long filtration time, and the filtrate was dark brown and cloudy.
The analysis of the quantitative whole water sample revealed a total of 8,741,000 cells per Liter. The most predominant phytoplankton genus was Skeletonema spp. at 4,912,000 cells/L. Other representative genera include Thalassiosira spp., Leptocylindrus spp., and Chaetoceros spp. This week's featured image (200x phase contrast) shows the diversity of the phytoplankton sample, containing many different genera. Phytoplankton are primary producers and contain chlorophyll to capture sunlight to produce energy.
Week of April 22 - 28, 2024
Fixed Site Network
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were dry, with only 0.05 inches on April 30th, recorded at T.F. Green. The Blackstone River flow declined this week, remaining below the 19-year daily median for the majority of the week. Surface salinity averaged 4.1 ppt and ranged from 1.2 ppt to 9.1 ppt. At the bottom, salinity averaged 13.5 ppt and ranged from 2.3 ppt to 27.1 ppt. Temperatures remained stabilized this week, averaging 12.7°C at the surface and ranging 10.0°C – 14.5°C. At the bottom, temperatures averaged 11.3°C and ranged 8.0°C – 14.4°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO average 10.5 mg/L and ranged from 9.5 mg/L to 11.7 mg/L.. Bottom DO concentrations averaged 9.3 mg/L and ranged from 8.1 mg/L to 11.3 mg/L. Chlorophyll readings remained comparable from last week, averaging 2.6 ug/L at the surface and 2.9 ug/L at the bottom. Maximum chlorophyll at the surface reached 14.3 ug/L on the afternoon of April 24th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that isolated portions of suspect chlorophyll data from April 28th were excluded from the summary.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
Week of April 15 - 21, 2024
Fixed Site Network
Phillipsdale Landing
Sondes were swap this week on the morning of April 16th. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were mostly dry, with only 0.4 inches of precipitation recorded at T.F. Green. The Blackstone River flow declined this week, remaining above the 19-year daily median for the week. Salinity at the surface averaged 1.8 ppt and ranged from 0.4 ppt to 4.4 ppt. At the bottom, salinity averaged 9.2 ppt and ranged from 0.4 ppt to 26.3 ppt. Temperatures continued to increase this week, averaging 12.9°C at the surface and 11.6 °C at the bottom. Surface temperatures ranged from 10.7°C to 15.5°C, while bottom temperatures ranged from 8.1°C to 15.3°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO remained similar to the previous week, averaging 10.5 mg/L and ranging 9.7-11.8 mg/L. Bottom water DO concentration averaged 9.7 mg/L and ranged from 7.7 mg/L to 11.6 mg/L. Chlorophyll concentrations remained low, averaging 2.7 ug/L at the surface and 2.6 ug/L at the bottom. Maximum surface chlorophyll readings reached 11.9 ug/L, recorded in the morning of April 20th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that isolated portion of suspect chlorophyll data from April 15th was excluded from the summary.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
Week of April 8 - 14, 2024
Fixed Site Network
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was good this week. Weather conditions included sporadic rain events, with 1.0 inches of precipitation recorded at T.F. Green. The Blackstone River flow increased during the 12th and 13th and remained above the 19-year daily median for the week. Surface salinity this week averaged 2.4 ppt and ranged from 0.2 ppt to 7.5 ppt. At the bottom, salinity averaged 8.6 ppt and ranged from 0.2 ppt to 26.4 ppt. Temperatures increased this week, averaging 10.5°C at the surface and 9.8°C bottom. Surface temperatures ranged from 6.5°C to 12.3°C, while bottom temperatures ranged from 5.9°C to 12.5°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO averaged 11.5 mg/L and ranged 10.0 – 12.7 mg/L. Bottom DO concentrations averaged 11.0 mg/L and ranged from 9.1 mg/L to 12.6 mg/L. Chlorophyll concentrations remained low, averaging 2.3 ug/L at the surface and 4.2 ug/L at the bottom. Maximum chlorophyll at the surface reached 15.1 ug/L on the morning of April 12th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that isolated portions of suspect chlorophyll data from April 8th to the 11th were excluded from the summary.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
Week of April 1 - 7, 2024
Fixed Site Network
Phillipsdale Landing
The Phillipsdale Landing sondes have been deployed for the season since April 2nd, 2024. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were wet this week, with a total of 2.22 inches recorded at T.F. Green, and the majority of rainfall occurring between the 2nd and 4th. The Blackstone River flow increased during the 4th and remained above the 19-year daily median for the week. Salinity at the surface averaged 1.8 ppt and ranged from 0.2 ppt to 5.7 ppt. At the bottom, salinity averaged 9.2 ppt and ranged from 0.2 ppt to 27.6 ppt. Temperatures this week averaged 7.4°C at the surface and 6.7°C at the bottom. Surface temperatures ranged from 5.8°C to 9.9°C, while bottom temperatures ranged from 5.6°C to 8.9°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO averaged 12.2 mg/L and ranged from 11.0-13.5 mg/L. Bottom water DO concentration averaged 11.6 mg/L and ranged from 9.2 mg/L to 13.6 mg/L. Chlorophyll remained low, averaging 1.6 ug/L at the surface and 3.1 ug/L at the bottom. Maximum surface chlorophyll readings reached 4.3 ug/L, recorded on the morning of April 4th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that an early portion of the bottom data is not included in the summary above due to bottom deployment getting into position.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
