U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 01/11/1982
Station ID: 8630225 SUPERCEDED DATE: 04/21/2003
Name: OYSTER BAY, CHINCOTEAGUE ISLAND
VIRGINIA
NOAA Chart: 12211 Latitude: 37° 56.5' N
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 20.8' W
To reach the tidal bench marks from the junction of State Route 175 and Main
Street in Chincoteague, proceed 0.4 mile northeast along Main Street, then right
0.4 mile southeast along Maddox Boulevard, then left 1.3 miles northeast along
Deep Hole Road, then left 0.1 mile northwest along Hibiscus Drive, then right
0.1 mile northeast along Pearl Drive, then right 0.1 mile south along Sunrise
Shore Road. The tide gage and staff were located on the dock on a side channel
of Oyster Bay.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 863 0225 A 1976
MONUMENTATION: Survey Disk VM#: 3243
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument at the south end of Sunrise Shore
Road, 73.3 feet southeast of the southeast corner of a two-story wood frame and
block house, 47.0 feet north of the northwest corner of a two-story wood frame
house, 3.4 feet southwest of power pole No. 14,33C, and flush with the ground.
BENCH MARK STAMPING: 863 0225 B 1976
MONUMENTATION: Survey Disk VM#: 3244
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument at the south end of Sunrise Shore
Road, 100.5 feet east of the southeast corner of a two-story wood frame and
block house, 100.4 feet northeast of power pole No. 14,33C, 5.0 feet south of
power pole No. 14, 33B, and flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 01/11/1982
Station ID: 8630225 SUPERCEDED DATE: 04/21/2003
Name: OYSTER BAY, CHINCOTEAGUE ISLAND
VIRGINIA
NOAA Chart: 12211 Latitude: 37° 56.5' N
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 20.8' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 863 0225 C 1976
MONUMENTATION: Survey Disk VM#: 3245
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument, 0.05 mile northwest of Deep Hole
Road, on the west side of Hibiscus Drive, across from Holly Drive, 44.0 feet
west of power pole No. 23X, 14.5 feet west of the centerline of the road, 4.5
feet east of power pole No. 23, and flush with the ground.
BENCH MARK STAMPING: 863 0225 D 1976
MONUMENTATION: Survey Disk VM#: 3246
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument, from the junction of Maddox
Boulevard and Deep Hole Road, 1.3 miles northeast along Deep Hole Road to a
cul-de-sac, 38.0 feet southeast of power pole No. 21, 22.5 feet southeast of the
centerline of the road, 3.0 feet southwest of power pole No. 21X, and 0.2 foot
below ground level.
BENCH MARK STAMPING: 863 0225 E 1976
MONUMENTATION: Survey Disk VM#: 3247
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument, from the junction of Maddox
Boulevard and Deep Hole Road, proceed 0.85 mile northeast along Deep Hole Road
to the intersection with County Dock Road at east corner of the intersection,
57.5 feet east of power pole No. 12-56, 54.0 feet southeast of a two-story
house, 3.5 feet northwest of a sign post, and 0.2 foot below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 01/11/1982
Station ID: 8630225 SUPERCEDED DATE: 04/21/2003
Name: OYSTER BAY, CHINCOTEAGUE ISLAND
VIRGINIA
NOAA Chart: 12211 Latitude: 37° 56.5' N
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 20.8' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: JR 5 1975
MONUMENTATION: Survey Disk VM#: 3248
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in concrete, at the intersection of Maddox Boulevard and
Deep Hole Road, in the south corner of the intersection, in line with the street
edge of a concrete apron, 10.3 feet northwest of the northwest corner of the
Ocean Building Supply, Inc., and at ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 01/11/1982
Station ID: 8630225 SUPERCEDED DATE: 04/21/2003
Name: OYSTER BAY, CHINCOTEAGUE ISLAND
VIRGINIA
NOAA Chart: 12211 Latitude: 37° 56.5' N
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 20.8' W
T I D A L D A T U M S
Tidal datums at OYSTER BAY, CHINCOTEAGUE ISLAND based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: NOVEMBER 1976
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8630055 Franklin City
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
MEAN HIGHER HIGH WATER MHHW = 1.75
MEAN HIGH WATER MHW = 1.63
MEAN TIDE LEVEL MTL = 0.86
MEAN LOW WATER MLW = 0.09
MEAN LOWER LOW WATER MLLW = 0.00
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
863 0225 A 1976 4.20 2.57
863 0225 B 1976 4.14 2.51
863 0225 C 1976 3.94 2.31
863 0225 D 1976 6.16 4.53
863 0225 E 1976 4.74 3.11
JR 5 1975 4.47 2.84
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 01/11/1982
Station ID: 8630225 SUPERCEDED DATE: 04/21/2003
Name: OYSTER BAY, CHINCOTEAGUE ISLAND
VIRGINIA
NOAA Chart: 12211 Latitude: 37° 56.5' N
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 20.8' 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.