LAND USE EFFECT ON WATER QUALITY IN WATERSHEDS OF 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. Studies have shown that land use differences such as urban, agricultural, and forests influence water quality of surface water bodies. To date there is no comprehensive surface water quality assessment data available for Otsego County. The goal of this study is to assess the chemical composition of surface water during baseflow conditions in the county and compare the sub-watersheds based on dominant land use differences. In addition, the collected data contribute to a baseline database that provides information about the current health of ecosystems to help sustainable development in the area. Water samples were collected once a month 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, and each sample was analyzed for cation (metals), anion (nutrients) and dissolved silica composition using atomic absorption spectroscopy, ion chromatography and wet chemistry methods coupled with spectrophotometry. The results show dominance of calcium and bicarbonate with pH values above 7 in all water samples. Sodium, chloride and sulfate are also significant components of the surface waters all year around with highest concentrations found in dominantly urban watersheds. Overall, nitrate and phosphate concentrations are low with some seasonal variations and higher values in the agriculture dominated watersheds. No significant metal contaminations are present in any of the samples. The water composition of surface waters in Otsego County, NY reflects bedrock geology of shale, sandstone and limestone at baseflow conditions. Further investigations are needed to elucidate the impact of storm events on nutrient and sediment loads to the Chesapeake Bay throughout the year.