U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
Station ID: 8638464 PUBLICATION DATE: 01/07/2011
Name: WILLCOX WHARF, CHARLES CITY
VA
NOAA Chart: 12251 Latitude: 37° 18.9' N ( 37.31500)
USGS Quad: CHARLES CITY Longitude: 77° 5.9' W ( -77.09830)
To reach from the intersection of Virginia Route 5 and Virginia Route 155, go
west on Route 5 3.6 km (2.2 mi) to a left on to Wilcox Wharf Road, go 1.7 km
(1.1mi) and bear right to stay on wilcox wharf road, continue 0.3 km (0.2 mi) to
the end of the road. The station is on the right.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 2 1971
DESIGNATION: 863 8464 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 19669
AGENCY: US Coastal & Geodetic Survey (CGS) IDB PID#:
SETTING CLASSIFICATION: Concrete Monument OPUS PID:
LATITUDE: 37° 19.0' N ( 37.31720) LONGITUDE: 77° 5.9' W ( -77.09813)
The bench mark is a disk in the top of a concrete monument 45.18 m (148.2 ft) SW
of the SW corner of a small brick building (restrooms), 13.42 m (44.0 ft) NW of
the west end of a metal guard rail at the terminus of Wilcox Road, 13.04 m (42.8
ft) West-SW of the center of Wilcox Road, and 7.6 cm (3 in) below ground level.
BENCH MARK STAMPING: Wilcox 2
DESIGNATION: 863 8464 Wilcox 2
MONUMENTATION: Triangulation Station disk VM#: 19792
AGENCY: US Army Corps of Engineers (USACE) IDB PID#: GV5343
SETTING CLASSIFICATION: Concrete Monument OPUS PID:
LATITUDE: 37° 19.0' N ( 37.31703) LONGITUDE: 77° 5.9' W ( -77.09825)
The bench mark is set in the top of a concrete monument located 68.91 m (226.1
ft) SW of the SW corner of a small brick building (restrooms), 34.93 m (114.6
ft) WSW of the center of Wilcox Road, and 27.64 m (90.7 ft) WSW of the west end
of a metal guard rail at the terminus of Wicox Road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
Station ID: 8638464 PUBLICATION DATE: 01/07/2011
Name: WILLCOX WHARF, CHARLES CITY
VA
NOAA Chart: 12251 Latitude: 37° 18.9' N ( 37.31500)
USGS Quad: CHARLES CITY Longitude: 77° 5.9' W ( -77.09830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8464 B 2010
DESIGNATION: 863 8464 B
MONUMENTATION: Tidal Station disk VM#: 19793
AGENCY: US Army Corps of Engineers (USACE) IDB PID#:
SETTING CLASSIFICATION: Concrete Monument OPUS PID:
LATITUDE: 37° 19.1' N ( 37.31836) LONGITUDE: 77° 5.9' W ( -77.09844)
The bench mark is a disk set in the top of concrete monument located 152.62 m
(500.7 ft) south of 863 8464 TIDAL 4, 135.52 m (444.6 ft) NNW of the west end of
a metal guard rail at the end of Wilcox Wharf Road, 104.39 m (342.5 ft) NNW of
the SW corner of a brick building (restrooms), and 6.71 m (22 ft) WNW of the
center of Wilcox Road.
BENCH MARK STAMPING: 8464 A 2010
DESIGNATION: 863 8464 A
MONUMENTATION: Flange-encased Rod VM#: 19794
AGENCY: US Army Corps of Engineers (USACE) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBBZ97
LATITUDE: 37° 19.0' N ( 37.31740) LONGITUDE: 77° 5.9' W ( -77.09793)
The bench mark is a flange-encased rod located 29.96 m (98.3 ft) NNE of the
west end of a metal guard rail at the end of Wilcox Wharf Road, 21.05 m (69.1
ft) SW of the SW corner of brick building (restrooms), and 8.59 m (28.2 ft) ENE
of the center of Wilcox Road. The datum point is crimped to a stainless steel
rod driven 7.01 m (23 ft) to refusal with concrete kick block and 5 in logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
Station ID: 8638464 PUBLICATION DATE: 01/07/2011
Name: WILLCOX WHARF, CHARLES CITY
VA
NOAA Chart: 12251 Latitude: 37° 18.9' N ( 37.31500)
USGS Quad: CHARLES CITY Longitude: 77° 5.9' W ( -77.09830)
T I D A L D A T U M S
Tidal datums at WILLCOX WHARF, CHARLES CITY based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: August 2010 - September 2010
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8638610 SEWELLS POINT, HAMPTON ROADS
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.766
MEAN HIGH WATER MHW = 0.694
MEAN SEA LEVEL MSL = 0.397
MEAN TIDE LEVEL MTL = 0.372
MEAN LOW WATER MLW = 0.049
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 2 1971 1.380 0.686
Wilcox 2 0.888 0.194
8464 B 2010 3.821 3.127
8464 A 2010 2.120 1.426
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
Station ID: 8638464 PUBLICATION DATE: 01/07/2011
Name: WILLCOX WHARF, CHARLES CITY
VA
NOAA Chart: 12251 Latitude: 37° 18.9' N ( 37.31500)
USGS Quad: CHARLES CITY Longitude: 77° 5.9' W ( -77.09830)
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.