Nutrient samples were collected from 14 river stations and eight bay stations on May 31st. Edgewood Shoal was sampled at the surface and bottom; all other bay stations were sampled at the surface only. In the five days prior to sampling, there was no rainfall recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN) concentration was observed at Warren Reservoir/Kickemuit River (1,770 ppb), while the highest total dissolved nitrogen (TDN) and dissolved inorganic nitrogen (DIN) concentrations were observed at Ten Mile River @ Central Ave. (TDN = 1,650 ppb, DIN = 1,360 ppb). The lowest TN was observed at Moshassuck River @ Footbridge at Mill St. (790 ppb), the lowest TDN was at Palmer River @ Rt. 6 (715 ppb), and the lowest DIN was at Coles River @ Milford Rd. (122 ppb).
Among the bay stations sampled, the highest surface TN, TDN, and DIN concentrations were observed at Phillipsdale Landing (TN = 1,250 ppb, TDN = 903 ppb, DIN = 570 ppb). The lowest surface TN and TDN concentrations were observed at Conimicut Point (TN = 444 ppb, TDN = 167 ppb), while several locations – Conimicut Point, Edgewood Yacht Club, Bullock Reach Buoy, and Edgewood Shoal – had surface DIN concentrations below the detection limit of 13.0 ppb. Chlorophyll a concentrations at the surface bay stations were relatively low at most sites but elevated at Edgewood Yacht Club, Pomham Rocks, and India Point Park; concentrations averaged 12.1 μg/L overall with a maximum of 26.6 μg/L at Pomham Rocks.
The next scheduled sampling date is June 14, 2023.