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 west recorder shelter,
Lake Ronkonkoma.
WELL CHARACTERISTICS.--Depth 1,305 ft. Upper casing
diameter 4 in; top of first opening 1,290 ft, bottom of last
opening 1,300 ft. Datum of gage is NGVD of 1929.
DATUM.--Land-surface datum is 134 ft above National
Geodetic Vertical Datum of 1929. Measuring point: Top of
casing, 2.34 ft above land-surface datum, 136.34 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,
136.38 ft above National Geodetic Vertical Datum of 1929, Mar.
31, 2016 to Mar. 14, 2024; Top of blue insert in 4" Steel
well, North Side, 136.333 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Unpublished records for October 1968 to September 1975 are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
measured, 40.92 ft above NGVD of 1929, June 5, 1979; lowest
recorded, 32.33 ft above NGVD of 1929, Oct. 3, 2017.