Phillipsdale Landing
Sondes were swapped for routine maintenance on the morning of March 7th. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were mostly dry, with only 0.29 inches on March 11th, recorded at T.F. Green. Blackstone River flow declined over the course of the week from its increased flow due to the March 4th storm (0.81 inches). It remained above the 18-year daily median for the majority of the week. Surface salinity remained well below bottom salinity. Surface salinity this week averaged 9.1 ppt and ranged from 3.8 ppt to 15.1 ppt. At the bottom, salinity averaged 22.0 ppt and ranged from 5.6 ppt to 30.3 ppt. Temperatures increased this week, averaging 5.8°C at both the surface and bottom . Surface temperatures ranged from 3.7°C to 7.9°C, while bottom temperatures ranged from 4.5°C to 7.1°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold of 2.9 mg/L throughout the week. Surface DO averaged 11.8 mg/L and ranged 10.8 – 13.6 mg/L. Bottom DO concentrations averaged 10.0 mg/L and ranged from 8.3 mg/L to 12.6 mg/L. Chlorophyll readings rose from the previous week, averaging 3.1 ug/L at the surface and 11.8 ug/L at the bottom. Maximum chlorophyll at the surface reached 18.7 ug/L on March 10th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that portions of chlorophyll data from the bottom sonde from March 7th and 8th are not included in the summary above due potential sediment interference which is common at this site.
Bullock Reach
Bullock Reach sondes will be deployed later this spring for the 2023 monitoring season.