Nutrient samples were collected from 14 river stations and 8 bay stations on July 26th. 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 were 0.47 inches of rainfall recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN) and total dissolved nitrogen (TDN) concentrations were observed at Ten Mile River @ Central Ave. (TN = 1,470 ppb, TDN = 1,550 ppb); the highest dissolved inorganic nitrogen (DIN) concentration was observed at Pawtuxet River @ Broad St. (1,120 ppb). The lowest TN and TDN were observed at Moshassuck River @ Footbridge at Mill St. (TN = 654 ppb, TDN = 688 ppb, average of duplicates), while the lowest DIN was at Coles River @ Milford Rd. (147 ppb).
Among the bay stations sampled, the highest surface TN was observed at Pomham Rocks (989 ppb), the highest surface TDN was observed at Phillipsdale Landing (940 ppb), and the highest surface DIN was observed at Pawtuxet Cove (679 ppb). The lowest surface TN was observed at India Point Park (TN = 731 ppb), while the lowest surface TDN and DIN were at Bullock Reach Buoy (TDN = 230 ppb, DIN = 24.0 ppb). Chlorophyll a concentrations at the surface bay stations were moderately elevated this week; concentrations averaged 14.5 μg/L overall with a maximum of 26.4 μg/L at Bullock Reach Buoy.
The next scheduled sampling date is August 8, 2023.