Name: Line of equal water-table altitude (contour interval 10 feet)
Display Field: INFER
Type: Feature Layer
Geometry Type: esriGeometryPolyline
Description: This data set consists of digital contours that represent the altitude of water table 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. Water-level data were collected from 335 wells to construct the contours at a map scale of 1:125,000. The water table altitude contours were digitized and compared to 1997, 2006, and 2010 potentiometric-surface altitude maps . The variable contour interval ranges from 5 to 120 feet above the National Geodetic Vertical Datum of 1929. This geographic information systems (GIS) data set is a digital representation of the potentiometric-surface contours presented in sheet 1 of Scientific Investigations Map 3270.
Definition Expression: N/A
Copyright Text: Prepared in cooperation with: Long Island Water Conference, Nassau County Department of Public Works, New York City Department of Environmental Protection, Port Washington Water District, Suffolk County Department of Health Services, Towns of North Hempstead and Shelter Island, Manhasset-Lakeville Water District