U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 05/25/1988
Station ID: 8530095 SUPERCEDED DATE: 04/21/2003
Name: ALPINE, HUDSON RIVER
NEW JERSEY
NOAA Chart: 12343 Latitude: 40° 56.7' N
USGS Quad: YONKERS Longitude: 73° 55.1' W
To reach the tidal bench marks proceed along the Palisades Interstate Parkway to
Alpine, continue to the west side of the Hudson River to Palisades State Park.
The bench marks are located in the vicinity of the piers and buildings of the
Palisades Interstate Park Commission, and the tide gage and staff were at the
Alpine Boat Basin.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1932
MONUMENTATION: Survey Disk VM#: 2420
AGENCY: PID#: KU1630
SETTING CLASSIFICATION: Rock Cliff
The bench mark is set vertically into the east face of a rock cliff of the
Palisades, 0.1 mile (0.2 km) north of the Alpine Yonkers ferry landing, 53.5
feet (16.3 m) SW of the SW corner of a small wood bridge, 32.0 feet (9.8 m)
north of the NW corner of the Cornwallis Headquarters, 10.0 feet (3.0 m) west of
the centerline of a gravel road on the west side of the house, and 2 feet (1 m)
above road level.
BENCH MARK STAMPING: NO 2 1932
MONUMENTATION: Survey Disk VM#: 2421
AGENCY: PID#: KU1631
SETTING CLASSIFICATION: Rock Cliff
The bench mark is set vertically into the rock face of the Palisades, 0.1 mile
(0.2 km) north of the Alpine Yonkers ferry landing, 117.0 feet (35.7 m) north of
Bench Mark NO 1 1932, 55.0 feet (16.8 m) SW of the SW corner of a refresh- ment
pavilion (north stand), 28.0 feet (8.5 m) west of the centerline of the
employee's road, 17.5 feet (5.3 m) SW of the SW corner of the old Alpine Trail
Monument, and 3.0 feet (0.9 m) above ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 05/25/1988
Station ID: 8530095 SUPERCEDED DATE: 04/21/2003
Name: ALPINE, HUDSON RIVER
NEW JERSEY
NOAA Chart: 12343 Latitude: 40° 56.7' N
USGS Quad: YONKERS Longitude: 73° 55.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 3 1932
MONUMENTATION: Survey Disk VM#: 2422
AGENCY: PID#: KU1632
SETTING CLASSIFICATION: Concrete Retaining Wall
The bench mark is set on top of and at the south end of a rock and concrete
retaining wall, 0.1 mile (0.2 km) north of the Alpine Yonkers ferry landing,
106.0 feet (32.3 m) north of Bench Mark NO 2 1932, 100.0 feet (30.5 m) NW of a
small pavilion, and 10 feet (3 m) east of the centerline of a trail.
BENCH MARK STAMPING: 0095 A 1975
MONUMENTATION: Survey Disk VM#: 2423
AGENCY: PID:
SETTING CLASSIFICATION: Concrete and Brick Foundation
The bench mark is set vertically into the east face of a concrete and brick
building, at the Alpine Boat Basin, east of exit 2 of the Palisades State Park,
117.9 feet (35.9 m) west of the chain link fence on the wood bulkhead at the
Hudson River, 114.8 feet (35.0 m) north of the NE corner of a concrete garage
building, 86.9 feet (26.5 m) from the SE corner, 15.3 feet (4.7 m) from the NE
corner of the building, and 2 feet (1 m) above the pavement.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 05/25/1988
Station ID: 8530095 SUPERCEDED DATE: 04/21/2003
Name: ALPINE, HUDSON RIVER
NEW JERSEY
NOAA Chart: 12343 Latitude: 40° 56.7' N
USGS Quad: YONKERS Longitude: 73° 55.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0095 B 1975
MONUMENTATION: Survey Disk VM#: 2424
AGENCY: PID:
SETTING CLASSIFICATION: Bed Rock
The bench mark is set vertically into the east face of the rock cliff of the
Palisades, 0.1 mile (0.2 km) north of the Alpine Yonkers ferry landing, 148.5
feet (45.3 m) north of Bench Mark NO 3 1932, 87.4 feet (26.6 m) NW of a 3-foot
high stone wall, 61.0 feet (18.6 m) north of the NE corner of a large stone
pavilion building, 41.6 feet (12.7 m) SW of the SW corner of the first of
several stone picnic tables along the shore, and 2 feet (1 m) above ground
level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 05/25/1988
Station ID: 8530095 SUPERCEDED DATE: 04/21/2003
Name: ALPINE, HUDSON RIVER
NEW JERSEY
NOAA Chart: 12343 Latitude: 40° 56.7' N
USGS Quad: YONKERS Longitude: 73° 55.1' W
T I D A L D A T U M S
Tidal datums at ALPINE, HUDSON RIVER based on:
LENGTH OF SERIES: 9 MONTHS
TIME PERIOD: MARCH-NOVEMBER 1976
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8518750 THE BATTERY, NY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (03/16/1977) = 6.20
MEAN HIGHER HIGH WATER MHHW = 4.24
MEAN HIGH WATER MHW = 3.98
MEAN TIDE LEVEL MTL = 2.09
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 1.31
MEAN LOW WATER MLW = 0.20
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (12/22/1977) = -2.73
* NGVD reference based on adjustment of 1956 and NOS levels of 1/12/76.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 1 1932 9.25 5.27
NO 2 1932 10.81 6.83
NO 3 1932 25.11 21.13
0095 A 1975 9.78 5.80
0095 B 1975 10.34 6.36
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 05/25/1988
Station ID: 8530095 SUPERCEDED DATE: 04/21/2003
Name: ALPINE, HUDSON RIVER
NEW JERSEY
NOAA Chart: 12343 Latitude: 40° 56.7' N
USGS Quad: YONKERS Longitude: 73° 55.1' W
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 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.