Water Table Contours in the Upper Glacial and Magothy Aquifers, April-May 2013

This polyline shapefile consists of digital contours that represent the water table altitude in the upper glacial and Magothy aquifer beneath Long Island, New York. The U.S. Geological Survey constructed a water table altitude map using ground-water levels measured in the upper glacial and Magothy aquifers during the spring of 2013. Contours were constructed at a scale of 1:125,000 from water-level data collected at 335 groundwater monitoring wells. The water table altitude contours were digitized and compared to 1997, 2006, and 2010 water table altitude maps . The variable contour interval ranges from 5 to 120 feet above the National Geodetic Vertical Datum of 1929 (NGVD29). This polyline shapefile is a digital representation of the potentiometric-surface contours presented in sheet 1 of Scientific Investigations Map 3326.