U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
To reach the tidal bench marks from the U.S. Post Office in Stony Point, proceed
south on U.S. Highway 9W for 0.5 km (0.3 mi) to Main Street, continue east on
Main Street for 2.4 km (1.5 mi) past U.S. Gypsum Board Corporations main plant
entrance to River Road, then south on River Road for 0.5 km (0.3 mi) to a dirt
road entrance to the loading dock/conveyor platform. The bench marks are
located along the catwalk leading to the loading dock, along River Road, and
along Main Street. The tide gage and staff were located on the north side of
the catwalk about 91 m (300 ft) east of the shoreline.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8924 A 1981
DESIGNATION: 851 8924 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 2394
AGENCY: National Ocean Survey (NOS) IDB PID#: LX1852
SETTING CLASSIFICATION: Concrete footing OPUS PID:
LATITUDE: 41° 13.1' N ( 41.21830) LONGITUDE: 73° 57.8' W ( -73.96330)
The primary bench mark is a disk set in concrete footing at the top of the NW
corner of the second of three concrete footings supporting the steel catwalk
leading from the shore to the gypsum loading platform, 1.98 m (6.5 ft) north of
the center of the catwalk, 0.52 m (1.7 ft) east of the west side of the footing,
and 0.52 m (1.7 ft) south of the north side of the footing, and 0.91 m above the
shoreline.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8924 B 1981
DESIGNATION: 851 8924 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 2395
AGENCY: National Ocean Survey (NOS) IDB PID#: LX1851
SETTING CLASSIFICATION: Concrete footing OPUS PID:
LATITUDE: 41° 13.1' N ( 41.21830) LONGITUDE: 73° 57.9' W ( -73.96500)
The bench mark is a disk set at the SW corner of the concrete footing at the
foot of the steel catwalk leading to the gypsum loading platform, 0.61 m (2.0
ft) south of the centerline of the catwalk, 0.52 m (1.7 ft) WNW of the south
metal I-beam of the arched entrance of the catwalk, 0.24 m (0.8 ft) north of the
south side of the footing, 0.15 m (0.5 ft) east of the west side of the footing,
and 0.61 m (2.0 ft) above ground.
BENCH MARK STAMPING: 8924 C 1981
DESIGNATION: 851 8924 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 2396
AGENCY: National Ocean Survey (NOS) IDB PID#: LX1849
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 41° 13.3' N ( 41.22170) LONGITUDE: 73° 57.9' W ( -73.96500)
The bench mark is a disk set in the top of the concrete seawall along the east
side of River Road and directly across the street from #2 River Road, 5.18 m
(17.0 ft) SE of the centerline of River Road, 2 m (7 ft) NE of the SW end of the
seawall, 0.18 m (0.6 ft) NW of the SW edge of the seawall. and 0.91 m (3.0 ft)
above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 851 8924 D 1982
DESIGNATION: 851 8924 D TIDAL
MONUMENTATION: Flange-encased Rod VM#: 2397
AGENCY: National Geodetic Survey (NGS) IDB PID#: LX1848
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 41° 13.5' N ( 41.22500) LONGITUDE: 73° 58.2' W ( -73.97000)
The bench mark is a flange-encased rod located on the NW side of the main
entrance of the U.S. Gypsum Board Corporation on East Main Street, 34.59 m
(113.5 ft) NW of the NW metal gate post of the main entrance to the plant, 15.39
m (50.5 ft) west of a fire hydrant, 8.84 m (29.0 ft) SW of the centerline of
Main Street, 3.51 m (11.5 ft) west of power pole #60000-44651, 0.30 m (1.0 ft)
NW of the chainlink fence around the plant, and 0.30 m (1.0 ft) NE of a witness
post. The bench mark is set level with the street, being the highest point of a
stainless steel rod driven 20.7 m (68 ft) to substantial resistance, and is
encased by a pipe with a stamped access cover.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 851 8924 E 1982
DESIGNATION: 851 8924 E TIDAL
MONUMENTATION: Flange-encased Rod VM#: 2398
AGENCY: National Geodetic Survey (NGS) IDB PID#: LX1847
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 41° 13.5' N ( 41.22500) LONGITUDE: 73° 57.9' W ( -73.96500)
The bench mark is a flange-encased rod located 0.3 km (0.2 mi) SE of the main
entrance gate of the U.S. Gypsum Board Corporation in the back yard of #19 Main
Street, 70 m (230 ft) NE of the centerline of Main Street, 17.83 m (58.5 ft) NE
of the east corner of a garage, 9.75 m (32.0 ft) SE of a chain link fence, and
3.35 m (11.0 ft) north of an ash tree. The bench mark is set 0.30 m (1.0 ft)
below ground, being the highest point of a stainless steel rod driven 13.4 m (44
ft) to substantial resistance, and encased by a pipe with a steel stamped access
cover.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
T I D A L D A T U M S
Tidal datums at HAVERSTRAW BAY based on:
LENGTH OF SERIES: 2 YEARS
TIME PERIOD: January 1982 - December 1983
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8518750 THE BATTERY, NEW YORK HARBOR
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (03/19/1983) = 1.688
MEAN HIGHER HIGH WATER MHHW = 1.120
MEAN HIGH WATER MHW = 1.035
MEAN SEA LEVEL MSL = 0.550
MEAN TIDE LEVEL MTL = 0.543
North American Vertical Datum NAVD88 = 0.500
MEAN LOW WATER MLW = 0.052
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (04/07/1982) = -0.793
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8924 A 1981 2.461 1.426
8924 B 1981 3.233 2.198
8924 C 1981 2.544 1.509
851 8924 D 1982 5.024 3.989
851 8924 E 1982 1.649 0.614
Foot Notes:
Bench marks 851 8924 D 1982 and 851 8924 E 1982 are based on one differential
leveling connection and do not meet the quality control standards of the NOS.
Therefore, caution should be used when deriving elevations for these marks.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8518924 PUBLICATION DATE: 04/30/2012
Name: HAVERSTRAW BAY
NY
NOAA Chart: 12343 Latitude: 41° 13.1' N ( 41.21830)
USGS Quad: HAVERSTRAW Longitude: 73° 57.8' W ( -73.96330)
D E F I N I T I O N S
Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal
Datum Epoch. It pertains to local mean sea level and should not be confused
with the fixed datums of North American Vertical Datum of 1988 (NAVD88).
NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum
constraint adjustment of Canadian/Mexican/United States leveling observations.
Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as
the single initial constraint. NAVD88 replaces NGVD29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD29 was originally derived from a general
adjustment of the first-order leveling networks of the U.S. and Canada after
holding mean sea level observed at 26 long term tide stations as fixed.
Numerous local and wide-spread adjustments have been made since establishment in
1929. Bench mark elevations relative to NGVD29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to
local MSL and other tidal datums may not be consistent from one location to
another.
The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique
identifiers for bench marks in the tidal and geodetic databases, respectively.
Each bench mark in either database has a single, unique VM# and/or PID# assigned.
Where both VM# and PID# are indicated, both tidal and geodetic elevations are
available for the bench mark listed. The NGS's Integrated Data Base (IDB PID)
provides geodetic datum based on traditionally leveled and bluebooked ties to
the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/.
The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based
on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/.
The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD88 elevations.
The NAVD88 elevation relationship shown in the table is derived from an average
of several bench mark elevations relative to tide station datum. As a result of
this averaging, NAVD88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD88 elevations listed for
each bench mark in the NGS database.