Bench Mark Sheet for 8667411, LOBECO, WHALE BRANCH, COOSAW RIVER SC

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


To reach the tidal bench marks from the intersection of U.S. Highway 21 and
State Highway 116 at the Marine Corps Air Station entrance, proceed north on
U.S. Highway 21 for 9.7 km (6.0 mi) to the J. V. Dunbar Sr. Memorial Bridge over
Whale Branch.  The bench marks are located in the median of U.S. Highway 21
leading south toward Beaufort.  The tide gage and staff were located on the
fender pilings on the east side of the bridge.


                         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  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  J 107 1962
                         DESIGNATION:          J 107

MONUMENTATION:           Bench Mark disk                       VM#:         6761
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CK1429
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   32° 32.4' N (  32.54000)          LONGITUDE:  80° 44.7' W ( -80.74500)


The primary bench mark is a disk set flush in the SW abutment of the J. V.
Dunbar Sr. Memorial Bridge, 6.95 m (22.8 ft) west of the SE corner of the
bridge, 4.88 m (16.0 ft) NE of utility pole #144553, and 3.81 m (12.5 ft) west
of the centerline of the northbound lane.



                         BENCH MARK STAMPING:  7411 B 1977
                         DESIGNATION:          866 7411 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         6762
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2200
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   32° 32.3' N (  32.53830)          LONGITUDE:  80° 44.7' W ( -80.74500)


The bench mark is a disk located south of the bridge, between the northbound and
southbound lanes of U.S. Route 21, 112.78 m (370.0 ft) SSW of bench mark J 107
1962, 108.81 m (357.0 ft) north of bench mark 7411 C 1977, 6.71 m (22.0 ft) WNW
of the centerline of the northbound lane, and 0.64 m (2.1 ft) east of a witness
post.  The bench mark is set at ground level, crimped to the top of a steel rod
driven 11.6 m (38 ft) to refusal, and encased in a 4-inch PVC pipe and concrete
kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  7411 C 1977
                         DESIGNATION:          866 7411 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         6763
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2201
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   32° 32.3' N (  32.53830)          LONGITUDE:  80° 44.7' W ( -80.74500)


The bench mark is a disk located south of the bridge along the west side of the
northbound lane of U.S. Route 21, 109 m (358 ft) north of bench mark 7411 F
1982, 108.81 m (357.0 ft) south of bench mark 7411 B 1977, 6.40 m (21.0 ft) west
of the centerline of the northbound lane, and 0.49 m (1.6 ft) east of a witness
post.  The bench mark is set at ground level, crimped to a steel rod driven 9.1
m (30 ft) to refusal, and encased in a 4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  7411 F 1982
                         DESIGNATION:          866 7411 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         6765
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2202
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32° 32.3' N (  32.53830)          LONGITUDE:  80° 44.7' W ( -80.74500)


The bench mark is a disk set in a concrete monument which is 1 m (3 ft) deep and
0.3 m (1 ft) in diameter, 109 m (358 ft) south of bench mark 7411 C 1977, 22.10
m (72.5 ft) east of the centerline of the southbound lane, 8 m (26 ft) west of
the centerline of the northbound lane, 0.73 m (2.4 ft) west of a witness post,
and at ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  7411 G 1982
                         DESIGNATION:          866 7411 G TIDAL

MONUMENTATION:           Survey disk                           VM#:         6771
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK4352
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: CK4352
LATITUDE:   32° 32.1' N (  32.53500)          LONGITUDE:  80° 44.8' W ( -80.74670)


The bench mark is a disk located south of the bridge, along a service road
conecting the northbound and southbound lanes of U.S. Route 21, 90.25 m (296.1
ft) SSW of bench mark 7411 F 1982, 16.15 m (53.0 ft) north of the turnaround
lane between the northbound and southbound lanes, 14.78 m (48.5 ft) ESE of the
centerline of the southbound lane, 7.71 m (25.3 ft) WNW of the centerline of the
northbound lane, and 0.46 m (1.5 ft) SSW of a witness post.  The bench mark is
set 3 cm (0.1 ft) below ground level, crimped to the top of a stainless steel
rod driven to refusal, and encased in a PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


                            T I D A L   D A T U M S 


Tidal datums at LOBECO, WHALE BRANCH, COOSAW RIVER based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           March 1978 - February 1979
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8667999 BEAUFORT


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     HIGHEST OBSERVED WATER LEVEL (07/19/1978)         =  3.083
     MEAN HIGHER HIGH WATER                     MHHW   =  2.542
     MEAN HIGH WATER                            MHW    =  2.424
     MEAN SEA LEVEL                             MSL    =  1.415
     North American Vertical Datum              NAVD88 =  1.414
     MEAN TIDE LEVEL                            MTL    =  1.244
     MEAN LOW WATER                             MLW    =  0.063
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/25/1979)         = -0.980

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     J 107 1962                                  4.827    2.403
     7411 B 1977                                 3.188    0.764
     7411 C 1977                                 3.398    0.974
     7411 F 1982                                 3.342    0.918
     7411 G 1982                                 3.580    1.156


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  6

                                                                                
Station ID: 8667411                         PUBLICATION DATE:  02/05/2004
Name:       LOBECO, WHALE BRANCH, COOSAW RIVER                
            SC
NOAA Chart: 11519                           Latitude:   32° 34.4' N (  32.57330)
USGS Quad:  BENNETTS POINT                  Longitude:  80° 44.7' W ( -80.74500)


                             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.

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