Phillipsdale Landing
Sondes were swapped for routine maintenance on the morning of January 10th. The batteries in the bottom sonde retrieved this week died the day prior to retrieval, resulting in a data gap of approximately 16 hours from January 9th 18:00 to January 10th 9:30. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions started dry, with Blackstone River flows declining compared to the week prior. Substantial rain on January 12th (0.69 inches) and 13th (0.65 inches), as recorded at T.F. Green, led to increased Blackstone River flows, resulting in decreased salinity at Phillipsdale at the end of the week. Over the whole week, surface salinity averaged 4.4 ppt and ranged from 1.4 ppt to 9.2 ppt. At the bottom, salinity averaged 17.3 ppt and ranged from 1.2 ppt to 30.0 ppt. Temperatures were similar this week to last, averaging 4.7°C at the surface and ranging 3.3°C – 6.4°C. At the bottom, temperatures averaged 5.7°C and ranged 3.9°C – 6.7°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold of 2.9 mg/L throughout the week. Surface DO averaged 12.3 mg/L and ranged 11.6 – 13.0 mg/L. Bottom DO concentrations averaged 10.3 mg/L and ranged from 8.5 mg/L to 13.0 mg/L. Chlorophyll readings remained low, averaging 1.1 ug/L at the surface and 3.2 ug/L at the bottom. Maximum chlorophyll at the surface reached just 2.7 ug/L this week. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location.
Bullock Reach
Bullock Reach sondes will be deployed later this spring for the 2023 monitoring season.