Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was fair to good this week. Weather conditions were wet this week, with a total of 2.93 inches recorded at T.F. Green, and the majority of rainfall occurring on the 13th and 14th. Blackstone River flow increased during the 13th and 14th and remained above the 18-year daily median for the majority of the week. Surface and bottom salinity dropped dramatically after the 13th -14th storm and increased river flows. Salinity at the surface averaged 4.7 ppt and ranged from 0.3 ppt to 13.0 ppt. At the bottom, salinity averaged 14.4 ppt and ranged from 0.4 ppt to 29.5 ppt. Temperatures this week averaged 6.3°C at the surface and 5.9 °C at the bottom. Surface temperatures ranged from 4.3°C to 9.1°C, while bottom temperatures ranged from 4.4°C to 7.3°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 12.4 mg/L and ranging 10.4-14.1 mg/L. Bottom water DO concentration averaged 11.0 mg/L and ranged from 8.1 mg/L to 13.7 mg/L. Chlorophyll concentrations rose from the previous week, averaging 4.5 ug/L at the surface and 12.4 ug/L at the bottom. Maximum surface chlorophyll readings reached 56.0 ug/L, recorded in the morning of March 13th. 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 surface sonde on March 13th and from the bottom sonde on March 14th and 16th were excluded from the summary this week due to suspected sediment interference.
Bullock Reach
Bullock Reach sondes will be deployed later this spring for the 2023 monitoring season.