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Bench Mark Sheet for 8666699, BLUFF POINT, WADMALAW 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Superseded Epoch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Small blue map location marker Unpublished bench mark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.

Error: There is no bench mark map available for 8666699 BLUFF POINT, WADMALAW RIVER, SC
Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  4

                                                                                
Station ID: 8666699                         PUBLICATION DATE:  08/11/2003
Name:       BEARS BLUFF, WADMALAW RIVER                       
            SC
NOAA Chart: 11522                           Latitude:   32° 38.8' N (  32.64670)
USGS Quad:  ADAMS RUN                       Longitude:  80° 15.4' W ( -80.25670)


To reach the tidal bench marks from the Johns Island post office proceed SW
along State Highway 700 (Maybank Highway) for 9.3 km (5.8 mi) to County Road
S-10-316 (Bear Bluff Road), then turn right and continue NW along County Road
S-10-316 for 14.2 km (8.8 mi) to the end of the pavement to the entrance of the
U.S. Fish & Wildlife Orangeburg National Fish Hatchery, Bears Bluff Station,
then continue SW for 0.3 km (0.2 mi) along a sand road that runs parallel with a
chain link fence, and then proceed 0.2 km (0.1 mi) north through a chain link
gate to the office.  The bench marks are along a sand road that follows the
river.  The tide gauge and staff were at the end of the pier on the Wadmalaw
River.


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


                 PRIMARY BENCH MARK STAMPING:  6699 A 1977
                         DESIGNATION:          866 6699 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4339
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2579
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   32° 38.8' N (  32.64670)          LONGITUDE:  80° 15.3' W ( -80.25500)


The primary bench mark is a disk located at the shore end of the pier, 5 m (18
ft) NNW of the edge of a small fish pond, 3 m (10 ft) NNE of the centerline of
the sand road, and 1.10 m (3.6 ft) SSW of a 2 m (6 ft) high seawall.  The bench
mark is set at ground level, crimped to the top of a copper-clad steel rod
driven 12.2 m (40 ft) to refusal, and encased in a PVC pipe and 0.43 m (1.4 ft)
diameter concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  4

                                                                                
Station ID: 8666699                         PUBLICATION DATE:  08/11/2003
Name:       BEARS BLUFF, WADMALAW RIVER                       
            SC
NOAA Chart: 11522                           Latitude:   32° 38.8' N (  32.64670)
USGS Quad:  ADAMS RUN                       Longitude:  80° 15.4' W ( -80.25670)


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


                         BENCH MARK STAMPING:  6699 B 1977
                         DESIGNATION:          866 6699 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4340
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2578
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   32° 38.8' N (  32.64670)          LONGITUDE:  80° 15.3' W ( -80.25500)


The bench mark is a disk located along the sand road running along the river
from the pier to the southern boundary of the station, 7 m (23 ft) east of the
approximate edge of a 15 m (50 ft) high river bank, 6.25 m (20.5 ft) west of the
centerline of the road, 2.87 m (9.4 ft) NW of the 1 m (4 ft) diameter blazed
cedar tree, and 0.76 m (2.5 ft) east of a witness post with sign.  The bench
mark is set 0.61 m (2.0 feet) above road level, crimped to the top of a
copper-clad steel rod driven 8.5 m (28 ft) to refusal, and encased in a PVC pipe
and  0.43 m (1.4 ft) diameter concrete kickblock.



                         BENCH MARK STAMPING:  6699 C 1977
                         DESIGNATION:          866 6699 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4341
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK2577
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   32° 38.8' N (  32.64670)          LONGITUDE:  80° 15.3' W ( -80.25500)


The bench mark is a disk located along the sand road running along the river
from the pier to the southern boundary of the station, at the fork of two
cleared paths, 5.12 m (16.8 ft) SSE of a 2.29 m (7.5 ft) diameter blazed oak
tree, 5 m (15 ft) west of the centerline of the sand road, 4.45 m (14.6 ft)
north of a lone 2.29 m (7.5 ft) diameter cedar tree, and 0.82 m (2.7 ft) NE of a
metal witness post with sign.  The bench mark is level with the sand road,
crimped to a copper-clad steel rod driven 9.1 m (30 ft) 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  3 of  4

                                                                                
Station ID: 8666699                         PUBLICATION DATE:  08/11/2003
Name:       BEARS BLUFF, WADMALAW RIVER                       
            SC
NOAA Chart: 11522                           Latitude:   32° 38.8' N (  32.64670)
USGS Quad:  ADAMS RUN                       Longitude:  80° 15.4' W ( -80.25670)


                            T I D A L   D A T U M S 


Tidal datums at BEARS BLUFF, WADMALAW RIVER based on:

     LENGTH OF SERIES:      12 MONTHS
     TIME PERIOD:           October 1977 - September 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8665530 CHARLESTON, COOPER RIVER ENTRANCE


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

     HIGHEST OBSERVED WATER LEVEL (06/01/1977)         =  2.569
     MEAN HIGHER HIGH WATER                     MHHW   =  2.041
     MEAN HIGH WATER                            MHW    =  1.933
     North American Vertical Datum              NAVD88 =  1.163
     MEAN SEA LEVEL                             MSL    =  1.117
     MEAN TIDE LEVEL                            MTL    =  0.999
     MEAN LOW WATER                             MLW    =  0.065
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/09/1978)         = -0.967

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     6699 A 1977                                 3.301    1.368
     6699 B 1977                                 5.303    3.370
     6699 C 1977                                 6.330    4.397


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

                                                                                
Station ID: 8666699                         PUBLICATION DATE:  08/11/2003
Name:       BEARS BLUFF, WADMALAW RIVER                       
            SC
NOAA Chart: 11522                           Latitude:   32° 38.8' N (  32.64670)
USGS Quad:  ADAMS RUN                       Longitude:  80° 15.4' W ( -80.25670)


                             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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Products available at 8666699 BLUFF POINT, WADMALAW RIVER, SC

Revised: 10/15/2013
NOAA / National Ocean Service
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