USGS Hydrologic Conditions Maps for Long Island, NY, 2010
Contact: Michael Como (mcomo@usgs.gov)
ph # (631) 736-0783 ext. 120
Note: Latest version, Year 2013, click here
Two user-friendly Map Viewers from U.S. Geological Survey:
1.
USGS Depth-to-Water tool for Long Island, NY, 2010
2. USGS online mapper for water-table altitude, and
potentiometric surface of the Magothy, Jameco, Lloyd, and North Shore aquifers on Long Island, NY, 2010
Description:
The U.S. Geological Survey (USGS), in cooperation with State and local agencies, systematically collects groundwater data at varying measurement frequencies to monitor the hydrologic conditions on Long Island, New York. Each year during April and May, the USGS conducts a synoptic survey of water levels to define the spatial distribution of the water table and potentiometric surfaces within the three main water-bearing units underlying Long Island -- the upper glacial, Magothy, and Lloyd aquifers (Smolensky and others, 1989) -- and the hydraulically connected Jameco (Soren, 1971) and North Shore aquifers (Stumm, 2001). These data and the maps constructed from them are commonly used in studies of Long Island’s hydrology and are used by water managers and suppliers for aquifer management and planning purposes.
Water-level measurements made in 503 monitoring wells, a network of observation and supply wells, and 16 streamgage locations across Long Island during April-May 2010 were used to prepare the maps in this report. Measurements were made by the wetted-tape method to the nearest hundredth of a foot. Water-table and potentiometric-surface altitudes in these aquifers were contoured by using these measurements. Water-table and potentiometric-surface altitudes in these aquifers were contoured by using these measurements. The water-table contours were interpreted by using water-level data collected from 16 streamgages, 349 observation wells, and 1 supply well screened in the upper glacial aquifer and (or) shallow Magothy aquifer; the Magothy aquifer’s potentiometric-surface contours were interpreted from measurements at 67 observation wells and 27 supply wells screened in the middle to deep Magothy aquifer and (or) the contiguous and hydraulically connected Jameco aquifer. The Lloyd aquifer’s potentiometric-surface contours were interpreted from measurements at 55 observation wells and 4 supply wells screened in the Lloyd aquifer or the contiguous and hydraulically connected North Shore aquifer. Many of the supply wells are in continuous operation and, therefore, were turned off for a minimum of 24 hours before measurements were made so that the water levels in the wells could recover to the level of the potentiometric head in the surrounding aquifer. Full recovery time at some of these supply wells can exceed 24 hours; therefore, water levels measured at these wells are assumed to be less accurate than those measured at observation wells, which are not pumped (Busciolano, 2002). In this report, all water-level altitudes are referenced to the National Geodetic Vertical Datum of 1929 (NGVD 29).
Hydrographs are included on these maps for selected wells that are instrumented with recording equipment. These hydrographs are representative of the 2010 water year to show the changes that have occurred throughout that period. The synoptic survey water level measured at the well is included on each hydrograph.
Three feature classes depict the potentiometric-surface
altitudes in the upper glacial, Magothy, and Lloyd aquifers. A raster dataset
depicts the estimated depth to water table beneath Long Island.
Download the Data and Metadata
(33.5mb Zip file):
Long Island 2010 Hydrologic Condition GIS Datasets
Supporting
USGS Report:
USGS Scientific Investigations Map 3270
(abstract & data dwnld instr., four PDF map sheets; scale 1:125,000; 68x22 in.; 29mb each):
Long Island 2010 Hydrologic Condition Maps
Suggested citation:
Monti, Jack, Jr., Como, Michael, and Busciolano, Ronald, 2013, Water-table and Potentiometric-surface altitudes in the Upper Glacial, Magothy, and Lloyd aquifers beneath Long Island, New York, April-May 2010: U.S. Geological Survey, Scientific Investigations Map 3270, 4 sheets, scale 1:125,000,
http://dx.doi.org/10.3133/sim3270
