U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 08/17/1988
Station ID: 8638051 SUPERCEDED DATE: 04/21/2003
Name: MESSICK POINT, BACK RIVER
VIRGINIA
NOAA Chart: 12238 Latitude: 37° 6.5' N
USGS Quad: HAMPTON Longitude: 76° 19.0' W
To reach the tidal bench marks from the intersections of Route 134 and 172 at
Drummonds Corner, Langley Research Center NASA, proceed north on State Route 172
for 2.1 miles (3.4 km) to Poquoson, Virginia, then turn right on State Route 171
and proceed 1.5 miles (2.4 km) to a 4-way intersection where State Route 171
turns into Poquoson Avenue, then proceed on Poquoson Avenue for 2.2 miles (3.5
km) and turn left onto Messick Road, then proceed 1.9 miles (3.0 km) to the end
of the road and Messick Point on the Back River. The bench marks are located
along Messick Road. The tide gage and staff were on pilings behind the Back
River Seafood, Inc. office.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8051 A 1982
MONUMENTATION: Survey Disk VM#: 3439
AGENCY: PID:
SETTING CLASSIFICATION: Deep Rod
The bench mark is located 144 feet (44 m) bearing 104o (mag) from Bench Mark
8051 B 1982, 26.0 feet (7.9 m) north of south bulkhead, 25.0 feet (7.6 m) west
of east bulkhead, and 0.3 foot (0.1 m) from a fiberglass witness post. The bench
mark is driven 34.0 feet (10.4 m) to refusal, and encased in 4-inch PVC pipe.
BENCH MARK STAMPING: 8051 B 1982
MONUMENTATION: Survey Disk VM#: 3440
AGENCY: PID:
SETTING CLASSIFICATION: Deep Rod
The bench mark is located 147 feet (45 m) bearing 138o (mag) from the telephone
power pole at the SW corner of the Back River Seafood, Inc. trailer office, 14.3
feet (4.4 m) east of west bulkhead, 10.3 feet (3.1 m) north of south bulkhead,
and 0.3 foot (0.1 m) from a fiberglass witness post. The bench mark is driven
34.0 feet (10.4 m) to refusal, and encased in 4-inch PVC pipe.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 08/17/1988
Station ID: 8638051 SUPERCEDED DATE: 04/21/2003
Name: MESSICK POINT, BACK RIVER
VIRGINIA
NOAA Chart: 12238 Latitude: 37° 6.5' N
USGS Quad: HAMPTON Longitude: 76° 19.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8051 C 1982
MONUMENTATION: Survey Disk VM#: 3441
AGENCY: PID:
SETTING CLASSIFICATION: Deep Rod
The bench mark is located 82.3 feet (25.1 m) bearing 214o (mag) from the SW
corner of the W. Haywood Forest Seafood Market Building, 49.7 feet (15.1 m)
bearing 138o (mag) from the NE corner of bulkhead which is part of a man made
core, and 0.4 foot (0.1 m) from a fiberglass witness post. The bench mark is
driven 34.0 feet (10.4 m) to refusal, and encased in a 4-inch PVC pipe and
concrete kickblock.
BENCH MARK STAMPING: 8051 D 1982
MONUMENTATION: Survey Disk VM#: 3442
AGENCY: PID:
SETTING CLASSIFICATION: Deep Rod
The bench mark is located 132 feet (40 m) bearing 262o (mag) from the NW corner
of Harbor Inn Restaurant, 63.3 feet (19.3 m) bearing 159o (mag) from Power Pole
E70 Vepco 107 at the intersection of Messick Road and the driveway leading to
the Crosby Forest Seafood Restaurant, and 0.2 foot (0.1 m) from a fiberglass
witness post. The bench mark is driven 26.0 feet (7.9 m) to refusal, and
encased in 4-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 08/17/1988
Station ID: 8638051 SUPERCEDED DATE: 04/21/2003
Name: MESSICK POINT, BACK RIVER
VIRGINIA
NOAA Chart: 12238 Latitude: 37° 6.5' N
USGS Quad: HAMPTON Longitude: 76° 19.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8051 E 1982
MONUMENTATION: Survey Disk VM#: 3443
AGENCY: PID:
SETTING CLASSIFICATION: Deep Rod
The bench mark is located 134 feet (41 m) bearing 187o (mag) from pole HE68 at
the bend in Messick Road, 26.4 feet (8.0 m) bearing 68o (mag) from Vepco power
pole on the east side of Messick Road where the road turns from east/west to
north/south, and 21.3 feet (6.5 m) bearing 230o (mag) from the NW corner of an
aluminum sided out building in the parking lot of Bills Fish dock. The bench
mark is driven 26.8 feet (7.9 m) to refusal, and encased in a 4-inch PVC pipe
and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 08/17/1988
Station ID: 8638051 SUPERCEDED DATE: 04/21/2003
Name: MESSICK POINT, BACK RIVER
VIRGINIA
NOAA Chart: 12238 Latitude: 37° 6.5' N
USGS Quad: HAMPTON Longitude: 76° 19.0' W
T I D A L D A T U M S
Tidal datums at MESSICK POINT, BACK RIVER based on:
LENGTH OF SERIES: 69 HWS & 70 LWS
TIME PERIOD: JUNE 6 - JULY 11, 1982
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8637624 GLOUCHESTER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (06/19/1982) = 3.81
MEAN HIGHER HIGH WATER MHHW = 2.61
MEAN HIGH WATER MHW = 2.48
MEAN TIDE LEVEL MTL = 1.33
MEAN LOW WATER MLW = 0.18
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (06/26/1982) = -0.17
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
8051 A 1982 8.57 6.09
8051 B 1982 8.56 6.08
8051 C 1982 7.55 5.07
8051 D 1982 4.75 2.27
8051 E 1982 4.62 2.14
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 08/17/1988
Station ID: 8638051 SUPERCEDED DATE: 04/21/2003
Name: MESSICK POINT, BACK RIVER
VIRGINIA
NOAA Chart: 12238 Latitude: 37° 6.5' N
USGS Quad: HAMPTON Longitude: 76° 19.0' 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.