U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
To reach the station from the intersection of State Route 60 (Pocahontas Hwy)
and Route 155 in Providence Forge, Virginia, proceed south on Route 155 for 11.9
km (7.4 mi) to the junction with Route 5 (John Tyler Memorial Highway), turn
left and proceed east on Route 5 for 14.6 km (9.1 mi) to County Road 623, turn
right and go 3.9 km (2.4 mi) to a side road on the right, turn right on County
Road 613 and proceed southerly then SE'ly for 2.9 km (1.8 mi) to a side road on
the right, turn right on Tettington Lane and go southerly then easterly for 0.3
km (0.2 mi) to the entrance of Tettington Plantation (private estates) marked by
two brick columns, and then continue westerly for 0.3 km (0.2 mi) to 19021
Tettington Lane, St Charles City, Va 23030 on the right. The tide gauge sensors
were at the end of the 85 m x 2 m (278 ft x 6 ft) wide wooden dock that has a
small L at the end along with a boat lift on the west side. The tide staff was
attached to a dock piling on the west side of the dock about 25 m (82 ft) from
shore.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8450 A 2007
DESIGNATION: 863 8450 A
MONUMENTATION: Flange-encased Rod VM#: 18555
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBBG45
LATITUDE: 37° 14.4' N ( 37.24042) LONGITUDE: 76° 56.6' W ( -76.94319)
The primary bench mark is set in a grassy lawn south of the free-standing
garage-residence at 19021 Tettington Lane, 93.10 m (305.4 ft) south of bench
mark 863 8450 C, 57.00 m (187.0 ft) south of the SE corner of the free-standing
garage residence, 16.10 m (52.8 ft) ENE of the center at the beginning of the
wooden dock (measured on a slope), and 14.95 m (49.0 ft) north of the southern
(outside) edge of a concrete block retaining wall. The bench mark is set 0.08 m
(0.3 ft) below grade, being the top of a stainless steel rod driven 13.4 m (44.0
ft) to refusal, and encased in a 0.18 m (0.6 ft) diameter NOS logo cover
imbedded in a subsurface concrete kick block.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8450 B 2007
DESIGNATION: 863 8450 B
MONUMENTATION: Tidal Station disk VM#: 18556
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 37° 14.4' N ( 37.24036) LONGITUDE: 76° 56.5' W ( -76.94181)
The bench mark is a disk set flush in the top of a 1.2 m (3.9 ft) tall x 0.20 m
(0.7 ft) diameter concrete post with imbedded rebars flush with the ground,
122.80 m (402.9 ft) ESE of bench mark 863 8450 C, 28.60 m (93.8 ft) ENE of the
centerline of the driveway at house number 19101, 22.80 m (74.8 ft) ESE of the
east edge of the cul-de-sac pavement, 15.44 m (50.7 ft) east of the NE corner of
an elevated green electrical box, and 9.20 m (30.2 ft) north of centerline of an
east-west dead end road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8450 C 2007
DESIGNATION: 863 8450 C
MONUMENTATION: Tidal Station disk VM#: 18557
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 37° 14.5' N ( 37.24114) LONGITUDE: 76° 56.6' W ( -76.94261)
The bench mark is a disk set flush in the top of a 1.2 m (3.9 ft) tall x 0.21 m
(0.7 ft) diameter concrete post with imbedded rebars flush with the ground just
NNE of the free standing garage-residence at 19021 Tettington Lane, 156.5 m (513
ft) ESE of bench mark 863 8450 D, 122.8 m (403 ft) WNW of bench mark 863 8450 B,
93.10 m (305.5 ft) north of bench mark 863 8450 A, 36.60 m (120.1 ft) ESE of the
centerline of the driveway leading to 19021 Tettington Lane, 25.60 m (84.0 ft)
WNW of the centerline of driveway at 19061Tettington Lane, 22.90 m (75.1 ft) NE
of the NE corner of a free standing garage-residence at 19021 Tettington Lane,
9.16 m (30.0 ft) NE of an elevated green electrical box, 4.50 m (14.8 ft) south
of the centerline of Tettington Lane and 1.50 m (4.9 ft) south of the south edge
of pavement.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8450 D 2007
DESIGNATION: 863 8450 D
MONUMENTATION: Tidal Station disk VM#: 18558
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 37° 14.5' N ( 37.24200) LONGITUDE: 76° 56.6' W ( -76.94417)
The bench mark is a disk set flush in the top of a 1.2 m (3.9 ft) tall x 0.21 m
(0.7 ft) diameter concrete post with imbedded rebars flush with the ground south
of the grey barn and boathouse on the north side of Tettington Lane, 156.5 m
(513 ft) WNW of bench mark 863 8450 C, 117.35 m (385.0 ft) ESE of bench mark 863
8450 E, 28.64 m (94.0 ft) NNW of the NW corner of an elevated green electrical
box, 18.00 m (59.0 ft) NE of the centerline of the first driveway at 18920
Tettington Lane, 13.50 m (44.3 ft) NNW of the centerline of the second driveway
at 18920 Tettington Lane, and 4.00 m (13.1 ft) NNE of the centerline of
Tettington Lane.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8450 E 2007
DESIGNATION: 863 8450 E
MONUMENTATION: Tidal Station disk VM#: 18559
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 37° 14.5' N ( 37.24242) LONGITUDE: 76° 56.7' W ( -76.94553)
The bench mark is a disk set in the grass along the inside of the first corner
past the eagle topped brick gate posts at Tettington Plantation Estates set
flush in the top of a 1.2 m (3.9 ft) tall x 0.3 m (1.0 ft) diameter concrete
post with imbedded rebars flush with the ground, 117.35 m (385.0 ft) WNW of
bench mark 863 8450 D, 33.95 m (111.4 ft) SSE of the eastern corner of the NE
eagle topped brick gate post at the estate entrance, 12.40 m (40.7 ft) ENE of
the centerline of the driveway at 18851 Tettington Lane, 4.60 m (15.1 ft) NNE of
the centerline of Tettington Lane and 1.60 m (5.2 ft) NNE of the edge of
pavement on the north side of Tettington Lane.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
T I D A L D A T U M S
Tidal datums at TETTINGTON, JAMES RIVER based on:
LENGTH OF SERIES: 2 YEARS
TIME PERIOD: August 2008 - July 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:
HIGHEST OBSERVED WATER LEVEL (11/13/2009) = 2.094
MEAN HIGHER HIGH WATER MHHW = 0.671
MEAN HIGH WATER MHW = 0.611
MEAN SEA LEVEL MSL = 0.343
MEAN TIDE LEVEL MTL = 0.326
MEAN LOW WATER MLW = 0.041
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/01/2009) = -0.456
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8450 A 2007 4.201 3.590
8450 B 2007 3.572 2.961
8450 C 2007 4.753 4.142
8450 D 2007 4.322 3.711
8450 E 2007 4.325 3.714
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8638450 PUBLICATION DATE: 01/07/2011
Name: TETTINGTON, JAMES RIVER
VA
NOAA Chart: 12251 Latitude: 37° 14.4' N ( 37.24000)
USGS Quad: CLAREMONT Longitude: 76° 56.6' W ( -76.94330)
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.