Nutrient samples were collected from seven river stations on May 17th and seven bay stations on May 18th. All bay stations were sampled at the surface and bottom. In the five days prior to sampling, there were 0.01 inches of rainfall recorded at T.F. Green.
Among the river stations sampled, the highest total nitrogen (TN), total dissolved nitrogen (TDN), and dissolved inorganic nitrogen (DIN) concentrations were observed at Ten Mile River @ Central Ave. (TN = 1,360 ppb, TDN = 1,310 ppb, DIN = 1,080 ppb). The lowest TN, TDN, and DIN concentrations were observed at Woonasquatucket River @ Manton Ave. Bridge (TN and TDN = 743 ppb, DIN = 538 ppb, average of duplicates).
Among the bay stations sampled, the highest surface TN, TDN, and DIN concentrations were observed at Pawtuxet Cove (TN = 1,110 ppb, TDN = 1,010 ppb, DIN = 778 ppb). The lowest surface TN and DIN concentrations were observed at Conimicut Point (TN = 439 ppb, DIN = 13.0 ppb), while the lowest surface TDN concentration was observed at Bullock Reach Buoy (149 ppb, average of duplicates). Chlorophyll a concentrations at the surface bay stations were relatively low, averaging 9.61 μg/L across all sites with a maximum of 14.0 μg/L (average of duplicates) at Bullock Reach Buoy.
The next scheduled sampling date is May 31, 2023.