U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
To reach the tidal bench marks from the courthouse at Surry, proceed NE along
State Highway 31 for about 6.9 km (4.3 mi) to Scotland and the ferry facilities
for the Scotland/Jamestown ferry. The bench marks are located in the vicinity
of the ferry landing and along State Highway 31. The tide gage and staff were
located on the ferry landing pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8433 A 2003
DESIGNATION: 863 8433 A
MONUMENTATION: Flange-encased Rod VM#: 17218
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID:
LATITUDE: 37° 11.0' N ( 37.18330) LONGITUDE: 76° 47.2' W ( -76.78670)
The bench mark is a flange-encased rod located on the west side of Route 31
(Rolfe Highway) north of Riverside Drive, in front of the residence at 16278
Rolfe Highway, 41 m (135 ft) WSW of bench mark Ferry 1938, 5.76 m (18.9 ft) WNW
of the centerline of Route 31, 5.52 m (18.1 ft) ENE of Virginia power pole
number DM14, 0.55 m (1.8 ft) east of a witness post and a brick retaining wall.
The datum point is 10 cm (0.3 ft) below the ground, being the top of a stainless
steel rod driven 21.3 m (70 ft) to refusal, in a sleeve extending to a depth 0.9
m (3.0 ft) and encased in a 5 - inch NOS logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: FERRY 1938
DESIGNATION: FERRY
MONUMENTATION: Horizontal Station disk VM#: 3447
AGENCY: US Coast & Geodetic Survey
(USC&GS) IDB PID#: GV0759
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 37° 11.0' N ( 37.18330) LONGITUDE: 76° 47.1' W ( -76.78500)
The bench mark is a disk set in the top of a concrete monument at the ferry
landing, 42 m (135 ft) ENE of bench mark 8433 A 2003, 6.6 m (21.7 ft) east of
the centerline of the highway, 5.9 m (19.4 ft) SE of the corner of the wharf
leading to the ferry, and level with the ground.
BENCH MARK STAMPING: NO 2 1971
DESIGNATION: 863 8433 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 3449
AGENCY: US Coast & Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Retaining wall OPUS PID:
LATITUDE: 37° 11.0' N ( 37.18330) LONGITUDE: 76° 47.2' W ( -76.78670)
The bench mark is a disk set in the top of a concrete retaining wall at the NW
corner of a private residence, about 162 m (531 ft) SE of the ferry landing, 24
m (79 ft) east of the centerline of the road at the ferry landing, 1 m (3 ft)
south of Vepco utility pole NB79, and 1 m (3 ft) above the dirt drive.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8433 B 2003
DESIGNATION: 863 8433 B
MONUMENTATION: Flange-encased Rod VM#: 17217
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBDL27
LATITUDE: 37° 10.9' N ( 37.18170) LONGITUDE: 76° 47.3' W ( -76.78830)
The bench mark is a flange-encased rod located at the NE corner of a triangular
shaped Virginia Department of Transportation (VDOT) commuter parking lot formed
by the intersection of Route 31 (Rolfe Highway) with Short Drive, 47 m (154 ft)
NNE of Virginia power pole number BK91, 23.5 m (77.1 ft) SSW of the centerline
of the intersection of Rolfe Highway and Short Drive, and 2.2 m (7.2 ft) south
of the Surry County welcome sign. The datum point is set 10 cm (.3 ft) below
the ground, being the top of a stainless steel rod driven 20.7 m (68 ft) to
refusal, in a sleeve extending to a depth of 0.9 m (3.0 ft), and encased in a 5
- inch NOS logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8433 C 2003
DESIGNATION: 863 8433 C
MONUMENTATION: Flange-encased Rod VM#: 17219
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID:
LATITUDE: 37° 10.9' N ( 37.18170) LONGITUDE: 76° 47.4' W ( -76.79000)
The bench mark is a flange-encased rod located at the intersection of Route 31
(Rolfe Highway) and Old Town Road on the west side of Route 31, 120 m (394 ft)
WNW of bench mark 8433 B 2003, 25.1 m (82 ft) ESE of Virginia power pole number
VK46, 7.5 m (25 ft) north of the centerline of Route 31, and 3.7 m (12 ft) NNE
of a fiberglass witness post. The datum point is set 10 cm (.3 ft) below the
ground, being the top of a stainless steel rod driven 21.9 m (72 ft) to refusal,
in a sleeve extending to a depth of 0.9 m ( 3.0 ft), and encased in a 5 - inch
NOS logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
T I D A L D A T U M S
Tidal datums at SCOTLAND, JAMES RIVER based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: July 2003 - August 2003
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 = 0.706
MEAN HIGH WATER MHW = 0.647
MEAN SEA LEVEL MSL = 0.351
MEAN TIDE LEVEL MTL = 0.349
MEAN LOW WATER MLW = 0.051
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8433 A 2003 2.616 1.969
FERRY 1938 1.658 1.011
NO 2 1971 7.467 6.820
8433 B 2003 19.140 18.493
8433 C 2003 20.243 19.596
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8638433 PUBLICATION DATE: 04/15/2013
Name: SCOTLAND, JAMES RIVER
VA
NOAA Chart: 12248 Latitude: 37° 11.1' N ( 37.18500)
USGS Quad: SURRY Longitude: 76° 47.0' W ( -76.78330)
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.