LOCATION.--Lat 40°49'32", long
73°05'59" referenced to North American Datum of 1927,
Suffolk County, NY, Hydrologic Unit 02030202, at Duncan Avenue
and Portion Road, in pumping center, in recorder shelter, Lake
Ronkonkoma.
WELL CHARACTERISTICS.--Depth 855 ft. Upper casing
diameter 4 in; top of first opening 840 ft, bottom of last
opening 850 ft. Datum of gage is NGVD of 1929.
DATUM.--Land-surface datum is 133.5 ft above National
Geodetic Vertical Datum of 1929. Measuring point: Top of
casing, 2.13 ft above land-surface datum, 135.63 ft above
National Geodetic Vertical Datum of 1929, Mar. 5, 1970 to Mar.
31, 2016; Top of blue insert in 4" Steel well, North Side,
135.67 ft above National Geodetic Vertical Datum of 1929, Mar.
21, 2016 to Mar. 14, 2024; Top of blue insert in 4" Steel
well, North Side, 135.623 ft above National Geodetic Vertical
Datum of 1929, Mar. 14, 2024 to present.
PERIOD OF RECORD.--October 1968 to current year.
Unpublished records for October 1968 to September 1975 are
available in files of the U.S. Geological Survey.
GAGE.--Water-level recorder installed August 1986;
15-minute recording interval. Periodic manual measurements made
by USGS personnel.
REMARKS.--Water level affected by nearby pumping.
Cellular water-level telemeter at station.
EXTREMES FOR PERIOD OF RECORD.--Highest water level
recorded, 54.81 ft above NGVD of 1929, May 14, 15, 2010; lowest
recorded, 43.06 ft above NGVD of 1929, Aug. 28, 2017.