U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
To reach the tide station from the junction of State highways 13 and 178 at the
north edge of Exmore, VA on the Eastern Shore, proceed northerly on route 178
for 1.45 km (0.90 mi) through Belle Haven, and make a left turn on Route 178 in
the center of Belle Haven. Continue westerly and northwesterly on Route 178
(Shields Bridge Road) for 2.01 km (1.25 mi) to a small bridge over Occohannock
Creek. Cross the creek and continue on route 178 westerly then northerly for
2.17 km (1.35 mi) to a side road left. Turn left on Indian Trail Road and go
westerly for 2.37 km (1.47 mi) to a cross road, at a slight angle, and a stop
sign. Continue westerly then southerly on Indian Trail Road for 1.45 km (0.90
mi) to a T intersection and stop sign. Turn right on Scarborough Neck Road and
go 0.97 km (0.60 mi) to a side road left. Turn left and proceed on Occohannock
Drive southerly for 1.85 km (1.15 mi) to a side road right. Turn right on Camp
Lane and go westerly for 0.40 km (0.25 mi) to the end of the road at the
entrance to the Camp Occohannock (straight ahead) and the Pruitt gravel driveway
to the left. Turn left and go southerly, easterly, then southerly for 0.40 km
(0.20 mi) on gravel driveway through the Pruitt property to the tide station on
the end of the wood pile, wood decked, "L" shaped dock, south of the fish house,
along the west edge of the property and the north side of Occohannock Creek.
The tidal bench marks are located in the vicinity.
T I D A L B E N C H M A R K S
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 4 1972
DESIGNATION: 863 2869 TIDAL 4
MONUMENTATION: Survey disk VM#: 3378
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete slab OPUS PID:
LATITUDE: 37° 33.4' N ( 37.55670) LONGITUDE: 75° 55.3' W ( -75.92170)
The primary bench mark is a disk set flush in a concrete slab at the NW corner
of a picnic shelter on the grounds of the Methodist Church, Camp Occohannock, on
the north shore of Occohannock Creek, 14.3 m (47.0 ft) NE of the top of the bank
of Occohannock Creek, 12.07 m (39.60 ft) NW of bench mark No 3 1972, 10.49 m
(34.4 ft) NNW of the SW corner of the concrete slab, 8.56 m (28.10 ft) WSW in
the NE corner of the concrete slab, 1.46 m (4.8 ft) SSE of the NW corner of the
concrete slab, and 0.64 m (2.1 ft) ENE of the west edge of the concrete slab.
The concrete slab contains several major cracks.
BENCH MARK STAMPING: NO 3 1972
DESIGNATION: 863 2869 TIDAL 3
MONUMENTATION: Survey disk VM#: 3377
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete slab OPUS PID:
LATITUDE: 37° 33.4' N ( 37.55670) LONGITUDE: 75° 55.3' W ( -75.92170)
TThe bench mark is a disk set flush in a concrete slab at the SE corner of a
picnic shelter on the grounds of the Methodist Church, Camp Occohannock, on the
north shore of Occohannock Creek, 83.97 m (275.5 ft) WNW of bench mark 2869 B
1982, 17.4 m (57.0 ft) NE of the top of the bank of Occohannock Creek, 12.07 m
(39.60 ft) SE of bench mark No 4 1972, 10.45 m (34.3 ft) SSE of the NE corner of
the concrete slab, 8.63 m (28.30 ft) ENE of the SW corner of the concrete slab,
and 1.43 m (4.70 ft) NW of the NW corner of the concrete slab.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2869 B 1982
DESIGNATION: 863 2869 B
MONUMENTATION: Survey disk VM#: 3381
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Unspecified steel rod OPUS PID:
LATITUDE: 37° 33.4' N ( 37.55670) LONGITUDE: 75° 55.3' W ( -75.92170)
The bench mark is located near the boundary of the Pruitt and Methodist Church -
Camp Occohannock property, on the north shore of Occohannock Creek, 83.97 m
(275.5 ft) ESE of bench mark No 3 1972, 61.66 m (202.3 ft) NW of bench mark 2869
C 2007, 37.89 (124.3 ft) SSE of the center of the western most pole of a
baseball backstop, 25.09 m (82.3 ft) WNW of the NW corner of the Pruitt house,
17.4 m (57.0 ft) NNE of the top bank of Occohannock Creek, 12.62 m (41.4 ft) NNW
of the center of a 0.6 m (1.5 ft ) diameter cedar tree, and 0.06 m (0.20 ft)
below the level of a mowed lawn. The bench mark is a disk crimped to an
unspecified steel rod and encased in a PVC pipe and concrete kick block.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2869 C 2007
DESIGNATION: 863 2869 C
MONUMENTATION: See descriptive text VM#: 18430
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBBH11
LATITUDE: 37° 33.4' N ( 37.55670) LONGITUDE: 75° 55.2' W ( -75.92000)
The bench mark is located in the front mowed lawn of the Pruitt residence, 61.66
m ( 202.3 ft) ESE of bench mark 2869 B 1982, 32.22 m (105.7 ft) SSW of the SE
corner of the Pruitt house, 28.10 m (92.2 ft) SSW of bench mark PRUITT 2003,
27.37 m (89.8 ft) SE of the SW corner of the raised porch of the Pruitt house,
21.37 m (70.1 ft) east of a metal flagpole, and 17.98 m (59.0 ft) NNE of the top
of the bank of Occohannock Creek. The bench mark is a punch mark set in the top
of a rounded 9/16 " diameter stainless steel rod driven 19.51 m (64.0 ft) to
refusal, the mark is protected with a PVC pipe and aluminum logo cover set in a
concrete kick block surrounding the monument. The logo cover is 0.06 m (0.20
ft) below ground and the datum point is 0.12 m (0.40 ft) below ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: PRUITT 2003
DESIGNATION: 863 2869 PRUITT
MONUMENTATION: Survey disk VM#: 18431
AGENCY: US Army Corps of Engineers (USE) IDB PID#:
SETTING CLASSIFICATION: Concrete slab OPUS PID:
LATITUDE: 37° 33.4' N ( 37.55670) LONGITUDE: 75° 55.2' W ( -75.92000)
The bench mark is a disk set in the SE corner of a concrete slab extending off
the SE part of the Pruitt house, 28.10 m (98.1 ft) NNE of bench mark 2869 C
2007, 27.46 m (90.1 ft) NNW of the NW corner of a fish house by the dock, 10.5 m
(34.3 ft) north of the south edge of the gravel driveway, 4.45 m (14.6 ft) south
of the SE corner of the Pruitt house, 0.14 m (0.45 ft) west of the east edge of
the concrete slab, and 0.06 m (0.20 ft) north of the south edge of the concrete
slab.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
T I D A L D A T U M S
Tidal datums at GASKINS PT., OCCOHANNOCK CREEK based on:
LENGTH OF SERIES: 4 MONTHS
TIME PERIOD: June 2007 - September 2007
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8636580 WINDMILL POINT, RAPPAHANNOCK RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (06/15/2007) = 1.153
MEAN HIGHER HIGH WATER MHHW = 0.623
MEAN HIGH WATER MHW = 0.571
MEAN SEA LEVEL MSL = 0.314
MEAN TIDE LEVEL MTL = 0.308
MEAN LOW WATER MLW = 0.046
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (05/16/2007) = -0.214
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 4 1972 1.737 1.166
NO 3 1972 1.761 1.190
2869 B 1982 1.890 1.319
2869 C 2007 1.789 1.218
PRUITT 2003 2.046 1.475
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8632869 PUBLICATION DATE: 09/11/2008
Name: GASKINS PT., OCCOHANNOCK CREEK
VA
NOAA Chart: 12226 Latitude: 37° 33.4' N ( 37.55670)
USGS Quad: WEST OF JAMESVILLE Longitude: 75° 55.0' W ( -75.91670)
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.