U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8638481 PUBLICATION DATE: 01/17/2013
Name: CITY POINT, HOPEWELL
VA
NOAA Chart: 12251 Latitude: 37° 18.8' N ( 37.31330)
USGS Quad: HOPEWELL Longitude: 77° 16.2' W ( -77.27000)
To reach from the intersection of Interstate 295 and Virginia Route 36, go NE on
route 36 for 3.2 km (2.0 mi) to intersection with Virginia Route 156, continue
straight on Virginia Route 156 for 2.2 km (1.4 mi) to left on Virginia route 10,
go 0.4 km (0.2 mi) to right on south Hopewell Street, go 0.1 km (0.1 mi) bear
left to stay on south Hopewell Street and continue 0.2 km (0.1 mi) to right on
Station Street, go 1.1 km (0.7 mi) to straight ahead on Ramsey Avenue, go 0.3 km
(0.2 mi) to left on Water Street, go 0.4 km (0.2 mi) to the station on the
right. The station is located on the pier at regional enterprises, 410 water
Street.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8481 A 1978
DESIGNATION: 863 8481 A
MONUMENTATION: Tidal Station disk VM#: 3465
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 37° 18.7' N ( 37.31245) LONGITUDE: 77° 16.3' W ( -77.27163)
The bench mark is a disk set in a concrete monument just north of a set of brick
steps leading up a hill to an old church on the west side of Water Street, 80 m
(262.5 ft) South of Church Street, 29.20 m (95.8 ft) SW of power pole number
LA33, 12.25 m (40.2 ft) South of power pole LP-32-74, and 8.56 m (28.1 ft) NW of
power pole LP-51.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8638481 PUBLICATION DATE: 01/17/2013
Name: CITY POINT, HOPEWELL
VA
NOAA Chart: 12251 Latitude: 37° 18.8' N ( 37.31330)
USGS Quad: HOPEWELL Longitude: 77° 16.2' W ( -77.27000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 7 1971
DESIGNATION: 863 8481 TIDAL 7
MONUMENTATION: Tidal Station disk VM#: 3464
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 37° 18.8' N ( 37.31392) LONGITUDE: 77° 16.3' W ( -77.27183)
The bench mark is a disk set in a concrete pad on the north side of the former
Delta Materials Company yard on Water Street, 33.83 m (111 ft) north of NW
corner of the Delta Materials building, 5.8 m (19 ft) west of the NW leg of a
batch bin adjacent to the railroad tracks and a crane on the river bank, 5.8 m
(19 ft) east of the east rail of the railroad tracks on the edge of Water
Street, and 1.2 m (3.9 ft) south of the southern wall of a cinder block shed on
the NW corner of the yard.
BENCH MARK STAMPING: 8481 B 1978
DESIGNATION: 863 8481 B
MONUMENTATION: Tidal Station disk VM#: 3466
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 37° 18.9' N ( 37.31462) LONGITUDE: 77° 16.3' W ( -77.27247)
The bench mark is a disk set in a concrete monument at the foot of a hill on the
west side of Water Street, 171.5 m (562.7 ft) north of the intersection of
Church and Water Streets, 10.67 m (35.0 ft) NW of power pole KB94, 8.98 m (29.5
ft) SW of power pole KB85, and 9.30 m (30.5 ft) west of the centerline of Water
Street.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8638481 PUBLICATION DATE: 01/17/2013
Name: CITY POINT, HOPEWELL
VA
NOAA Chart: 12251 Latitude: 37° 18.8' N ( 37.31330)
USGS Quad: HOPEWELL Longitude: 77° 16.2' W ( -77.27000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8481 D 2010
DESIGNATION: 863 8481 D
MONUMENTATION: Tidal Station disk VM#: 19790
AGENCY: US Army Corps of Engineers (USACE) IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 37° 18.9' N ( 37.31480) LONGITUDE: 77° 16.3' W ( -77.27202)
The bench mark is a disk set in the concrete fundation for a large mooring
bollard, 38.65 m (126.8 ft) North-NE of power pole KB94, 30.62 m (100.5 ft) NE
of the centerline of Water Street, 6.72 m (22 ft) East of unnumbered power pole
with light and switchbox, and 1.78 m (5.8 ft) SW of the Riverside face of and
old concrete bulkhead.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8638481 PUBLICATION DATE: 01/17/2013
Name: CITY POINT, HOPEWELL
VA
NOAA Chart: 12251 Latitude: 37° 18.8' N ( 37.31330)
USGS Quad: HOPEWELL Longitude: 77° 16.2' W ( -77.27000)
T I D A L D A T U M S
Tidal datums at CITY POINT, HOPEWELL based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: February 2012 - April 2012
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 = 0.862
MEAN HIGH WATER MHW = 0.783
MEAN SEA LEVEL MSL = 0.431
MEAN TIDE LEVEL MTL = 0.410
MEAN LOW WATER MLW = 0.036
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8481 A 1978 4.784 4.001
NO 7 1971 2.973 2.190
8481 B 1978 2.904 2.121
8481 D 2010 2.057 1.274
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8638481 PUBLICATION DATE: 01/17/2013
Name: CITY POINT, HOPEWELL
VA
NOAA Chart: 12251 Latitude: 37° 18.8' N ( 37.31330)
USGS Quad: HOPEWELL Longitude: 77° 16.2' W ( -77.27000)
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.