WATER QUALITY ASSESSMENT OF SURFACE WATER IN OTSEGO COUNTY, NY

Otsego County lies in the Upper Susquehanna River watershed that is one of the major suppliers of fresh water into the Chesapeake Bay. The southern part of the county is a prospect for natural gas extraction via hydraulic fracturing method. To date there is no comprehensive surface water quality assessment data available for the county. The goal of this study is to determine the current state of water quality of surface water during baseflow conditions and build a baseline database that can be used for comparison in future assessments of any potential industrial impact to Otsego County, NY.

Each month water samples were collected at 50 sites for a calendar year throughout Otsego County. At each site, field parameters such as dissolved oxygen, electrical conductivity, pH, temperature, and turbidity were recorded. Water samples were filtered with 0.45 µm nylon filters and preserved using concentrated nitric acid to lower the pH below 2 for cation and by freezing for anion analyses. Various spectroscopic and chromatographic methods were employed to determine the cation and anion composition of the water samples.

The chemical composition of water reflects the bedrock geology of the watershed during baseflow conditions. The dominating ions are calcium and bicarbonate, and the pH values are above 7 in all samples. Sodium, chloride and sulfate are also significant components of the surface water all year around. Overall, nitrate and phosphate concentrations are low with some seasonal variations and no significant metal contaminations are present. Turbidity values are low during baseflow conditions. The water quality of surface water in Otsego County, NY is good, but further investigations are needed to elucidate the impact of storm events on nutrient and sediment loads to the Chesapeake Bay throughout the year.