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.