WATER QUALITY MONITORING IN THE SOUTH SHORE ESTUARIES OF LONG ISLAND, NEW YORK

Water quality concerns are a rising issue in the south shore estuaries of Long Island, NY. However, there are currently relatively little water quality data being collected in the western estuaries that receive drainage from heavily urbanized watersheds. Here we present preliminary results from a new data collection effort by Operation SPLASH, a volunteer organization that for the past three decades has been involved in pollution abatement and education on Long Island. Data were collected over a 12-week period in the summer of 2017 at five different estuaries, specifically (west to east): Mill River (MLR), Parsonage Creek (PAR), East Bay (EBAY), Jones Creek (JCK), and Neguntatogue Creek (NEG). A Manta-2 water probe was used to collect in situ measurements of water temperature, salinity, dissolved oxygen, turbidity and chlorophyll-a from both near the surface and near the bottom of the water column. In addition, surface water samples were collected for laboratory analysis of chlorophyll-a.

Measurements ranged as follows in the estuaries during the study period: temperature had a high of 29.6 °C (PAR) and a low of 22.1 °C (EBAY), salinity had a high of 52.5 ppt (MLR) and a low of 29.3 ppt (NEG), dissolved oxygen had a high of 85.0% (EBAY) and a low of 66.6% (NEG), turbidity had a high of 4.66 NTU (MLR) and a low of 3.3 NTU (EBAY), and chlorophyll-a had a high of 19.43 μg/L (PAR) and a low of 5.92 μg/L (EBAY). The parameters tested are often influenced by point and non-point pollution sources such as effluent from sewage treatment plants, runoff from golf courses, or other land uses. The high salinity, turbidity, and relatively high chlorophyll-a concentrations at Mill River suggest that the Bay Park Wastewater Treatment Plant and golf course adjacent to the estuary may be impacting water quality. The high turbidity and low dissolved oxygen at Neguntatogue Creek may similarly be influenced by the neighboring golf course and infrastructure. Relationships between the parameters tested and the potential point and non-point sources may be better understood if nitrogen and phosphorus concentrations are also monitored in further studies. In addition, the use of data loggers for continuous in situ measurements may reduce some human errors and missed data.