Phillipsdale Landing
Overall, the water quality at Phillipsdale Landing was good this week. There was light rain with 0.92 inches of rain recorded at T.F. Green. The Blackstone River flow increased throughout the week. Surface salinity averaged 11.9 ppt and ranged from 3.2 ppt–25.9 ppt. At the bottom, salinity averaged 24.0 ppt and ranged from 3.9 ppt–30.3 ppt. Temperatures decreased this week, averaging 12.6°C at the surface and 14.6°C at the bottom. Surface temperatures ranged from 10.0°C–14.8°C, while bottom temperatures ranged from 11.0°C–16.0°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO>2.9mg/L) in both the surface and bottom waters. Surface DO averaged 8.8 mg/L and ranged from 6.2 mg/L–10.5 mg/L. Bottom DO concentrations averaged 6.1 mg/L and ranged from 4.2 mg/L–9.8 mg/L. Chlorophyll readings remained relatively constant compared to last week, averaging 0.5 µg/L at the surface and 2.0 µg/L at the bottom. Maximum chlorophyll at the surface reached 2.8 µg/L on the morning of November 2nd. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock’s Reach
Sondes were swapped the afternoon of October 27th. Overall, water quality was good at Bullock’s Reach this week. Salinity averaged 27.8 ppt, 29.3 ppt, and 30.9 ppt at the surface, middle, and bottom sondes, respectively. Surface salinity ranged 9.8–30.5 ppt, mid-depth salinity ranged 26.8–30.9 ppt, and bottom salinity ranged 29.4–32.0 ppt. Surface temperature averaged 14.1°C and ranged from 12.0°C to 15.2°C. Mid-depth temperatures averaged 14.3°C and ranged from 12.8°C to 15.6°C. Bottom temperatures averaged 14.7°C and ranged from 12.9°C to 15.9°C.
Dissolved oxygen (DO) at Bullock’s Reach remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO averaged 8.1 mg/L and ranged 7.6–10.4 mg/L. In the mid-depth waters, DO averaged 7.9 mg/L and ranged 7.3–9.6 mg/L. At the bottom, DO averaged 7.5 mg/L and ranged 6.8–8.3 mg/L. Chlorophyll concentrations decreased at all depths compared to last week. Readings averaged 1.3 µg/L at the surface, 2.6 µg/L at mid-depth, and 4.9 µg/L at the bottom. The maximum surface chlorophyll was 3.2 µg/L on the morning of October 27th.