This station is operated in cooperation
NYS Department of Environmental
Lat 40°37'02", long 73°45'30"
referenced to North American Datum of 1927, Nassau County, NY,
Hydrologic Unit 02030202, at Town of Hempstead Inwood Marina, in
PERIOD OF RECORD.--
July 2002 to current year. June 1979 to July
2002, in files of Town of Hempstead Department of Conservation &
Water-stage recorder. Datum of gage is NGVD of 1929. June
1979 to January 1991, water-stage recorder at site 600 ft
Records excellent, except those for Nov. 20, Nov. 22
to Jan. 4, Jan. 6-7, June 11-18, June 28 to July 21, and July 23 to
Sept. 30, which are good. Satellite and telephone elevation telemeter
EXTREMES FOR PERIOD OF RECORD.--
Maximum elevation, 7.53 ft, Aug.
28, 2011; minimum elevation, -5.52 ft, Mar. 9, 2005.
EXTREMES OUTSIDE PERIOD OF RECORD.--
Storm tides of Dec. 11,
1992, and Mar. 14, 1993, reached elevations of 8.9 and 8.3 ft,
respectively, from information provided by Town of Hempstead Department
of Conservation & Waterways. Minimum elevation recorded, -5.0 ft,
Dec. 12, 2000, Feb. 11, 2001, from information provided by Town of
Hempstead Department of Conservation & Waterways.
Derived from NY Annual Water-Data Report 2011
Peak Flow and Stage Information
Elevation (observed) and tide elevation (predicted)
for this station are reported to NGVD 1929. To convert data to
NAVD 1988 subtract 1.10 ft. To convert data to MLLW datum add
2.23 ft. These corrections vary from site to site.
is the National Geodetic Vertical Datum of 1929, formerly called
"mean sea level" or "Sea Level Datum of
1929." NGVD 1929 was a general adjustment of the first-order
level nets fit to mean sea level at 26 tide gages in the US and
is the North American Vertical Datum of 1988, which is a geodetic
datum derived from a general adjustment of the first-order level
nets fit to 1 tide gage in eastern Canada.
mean lower low water, which is a site-specific datum determined
by averaging the lowest of the 2 low tides that occur each day
over a 19-year tidal epoch. For tide gages with less than 19
years of record, this datum is estimated by correlation with
long-term tide gages.
Additional sensor graph(s) available (click on graph or sensor
elevation, astronomical-tide elevation, and residual water level
Graph updated every 15 minutes
link to graph