GEOCHEMISTRY OF THE SUSQUEHANNA RIVER AND PINE LAKE AREA, NY, USA

The Susquehanna River is the longest river on the East coast of the USA. It provides drinking water for much of Pennsylvania, as well as water for agriculture and industrial uses in three states. The goal of this study was to analyze the water quality of the Upper Susquehanna River between Cooperstown and Unadilla, NY, and the Pine Lake area, West Davenport, NY, of which there has been little research completed. Water samples were collected at 14 locations along the river and 2 locations at the lake every two weeks during the summer of 2010. Various field parameters were measured on site, such as pH, dissolved oxygen, temperature, and dissolved and suspended solids. Particular attention was paid to the outflow of Oneonta’s Waste Water Treatment Plant (WWTP). The water samples were analyzed for numerous cations (e.g. Na, Ca, Mg, Zn, and Ni), and anions (fluoride, chloride, nitrate, sulfate and phosphate) by atomic absorption spectroscopy (AA) and ion chromatography (IC), respectively.

The river water chemistry showed a consistent composition through the summer months reflecting the limestone, sandstone and shale bedrock geology of the watershed with an average pH of 8. Base cation concentrations decreased from the headwaters at Cooperstown toward Unadilla. Calcium decreased from 41 to 22 mg/L and Mg from 3.5 mg/L to 2.0 mg/L. These cations were not affected by the WWTP. Sodium content was 9 mg/L for all sites, but the WWTP released 60 to 70 mg/L of Na. However, by 300 m downstream from the WWTP sodium was back to 12 mg/L because the volume of the river is large enough to dilute the outflow waters. Other metals were below detection limit of the AA. Anions showed similar patterns to cations with an average of 22 mg/L for chloride, 8 mg/L for sulfate, 5 mg/L for nitrate, with phosphate and flouride below the detection limit of the IC. The WWTP released about 10-times greater concentrations of chloride and nitrate, and doubled sulfate, but again the effect was neutralized by 300 m downstream from the WWTP. The Pine Lake area water showed significantly lower concentrations of all analyzed compounds. Overall, all tested properties of the water were within limits set by the EPA, including the WWTP outflow. These results showed that the Upper Susquehanna River watershed is clean, but continuous monitoring is required to ensure the good water quality.