Hydrogeology and water quality of the Tug Hill glacial aquifer in northern New York

Abstract

The Tug Hill aquifer, in northern New York, is a 47-mile-long, 0.25-to-3.5-mile-wide, crescent-shaped Pleistocene sand and/or gravel deposit. The northern and central parts of the aquifer are under water-table conditions; the southern part has both water-table and discontinuous confined conditions. Groundwater and streams in the northern and central parts flow westward; those in the southern part flow from the edges of the valley to West Branch Fish Creek, which flows southeastward along the center of the valley. Principal sources of aquifer recharge are (1) infiltration of precipitation on the aquifer, estimated to be 137 million gallons per day, (2) infiltration form small streams that cross the north half of the aquifer, estimated to be 4.9 million gallons per day, and (3) seepage of runoff from adjacent till and bedrock, estimated to be 11.4 million gallons per day. Groundwater discharges from the aquifer (1) by evapotranspiration, (2) through pumping, (3) as subsurface flow the southern end of the aquifer at McConnellsville, (4) as seepage to springs, wetlands, and streams along the western margin of the central and northern parts of the aquifer, and (5) as seepage to tributary streams and West Branch Fish Creek on the valley flat. Good-quality water thatmore » is suitable for drinking and most other uses is found in most parts of the aquifer. The pH of the groundwater in the study area ranges from 5.9 to 8.0, with a median of 7.5. Water in the northern part, which is underlain by limestone, has a specific conductance and higher concentrations of hardness, alkalinity, calcium, and sulfate than water in other parts of the aquifer, which are underlain by shale, siltstone, and sandstone. Median concentrations of hardness, dissolved solids, chloride, and sulfate in the Tug Hill aquifer were less than those in six other upstate New York aquifers.« less