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Bench Mark Sheet for 8662746, WINYAH BAY, SOUTH ISLAND PLANTATION 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


To reach the tidal bench marks from North Santee River Bridge on U.S. Highway
17, proceed north on U.S. Highway 17 for 1.0 km (0.6 mi) to State Highway
S-22-30.  Turn right onto State Highway S-22-30 and go east for 7.7 km (4.8 mi)
to the end of the paved road.  Turn left and continue north on State Highway
S-22-30 for 4.5 km (2.8 mi) to Route S-22-18.  Turn right onto Route S-22-18 and
go east for 1.1 km (0.7 mi) to a ferry crossing the Intracoastal Waterway.  Take
the ferry and continue 7.2 km (4.5 mi) along the dirt road (passing the entrance
to an estate on South Island).  Turn left at the entrance past garages and sheds
and go north for 0.8 km (0.5 mi) to the Coast Guard Station.  The bench marks
are along the dirt road leading to the Coast Guard Station.  The tide gauge and
staff were on the north end of the Coast Guard pier, east of Bench Mark W.B. NO.
1 1975.


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


                 PRIMARY BENCH MARK STAMPING:  WB NO 1 1975
                         DESIGNATION:          866 2746 TIDAL WB 1

MONUMENTATION:           Tidal Station disk                    VM#:          586
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD0887
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The primary bench mark is a disk located near the base of the Coast Guard pier,
29.08 m (95.4 ft) east of the NE corner of the maintenance garage, 13.1 m (43
ft) NW of the NW corner of a wooden boat ramp, 9 m (28 ft) east of the center of
the road, 1.68 m (5.5 ft) SE of the SW corner of a walkway to a dock, and 0.6 m
(2 ft) south of the south edge of a walkway to a dock.  The bench mark is
crimped to a copper-clad steel rod driven 11.0 m (36 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  2 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  WB NO 2 1975
                         DESIGNATION:          866 2746 TIDAL WB 2

MONUMENTATION:           Tidal Station disk                    VM#:          587
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD0884
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.3' W ( -79.20500)


The bench mark is a disk located 21 m (69 ft) WSW of bench mark WB NO 1 1975, 12
m (39 ft) SW of the center of the road, 12 m (39 ft) east of the SE corner of
the maintenance garage, and 1 m (3 ft) east of a power pole with a meter and
light. The bench mark is crimped to the top of a copper-clad steel rod driven
11.0 m (36 ft) to refusal, and encased in a 4-inch PVC pipe and concrete
kickblock.



                         BENCH MARK STAMPING:  WB NO 4 1975
                         DESIGNATION:          866 2746 TIDAL WB 4

MONUMENTATION:           Tidal Station disk                    VM#:          589
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD0882
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.3' W ( -79.20500)


The bench mark is a disk located 65.3 m (214.3 ft) south of bench mark WB NO 1
1975, 17.83 m (58.5 ft) SE of the centerline of the dirt road, 16.15 m (53.0 ft)
NW of the north end of a damaged wooden bulkhead, and 0.30 m (1.0 ft) north of a
witness post.  The bench mark is crimped to the top of a copper-clad steel rod
driven 11.0 m (36 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  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  WB NO 5 1975
                         DESIGNATION:          866 2746 TIDAL WB 5

MONUMENTATION:           Tidal Station disk                    VM#:          590
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD0881
SETTING CLASSIFICATION:  Copper Pipe                           OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.3' W ( -79.20500)


The bench mark is a disk braized to a 1.2 m (4.0 ft) long copper pipe surrounded
by soil-crete, located near the edge of the woods at the back of the corner of
an open field, 66 m (216 ft) west of bench mark WB NO 4 1975, 36.73 m (120.5 ft)
WNW of the centerline of the dirt road, 1.19 m (3.9 ft) SW of an unnumbered
power pole, 0.3 m (1 ft) NE of a witness post, and 0.06 m (0.2 ft) above ground.



                         BENCH MARK STAMPING:  2746 G 1978
                         DESIGNATION:          866 2746 G

MONUMENTATION:           Tidal Station disk                    VM#:          591
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The bench mark is a disk located on the east side of the dirt road leading to
the gage site, 46 m (150 ft) SSE of bench mark WB NO 5 1975, 45.26 (148.5 ft) SE
of a power pole on the west side of the road, 10.1 m (33 ft) NE of the
easternmost cedar tree with a cross cut on its north side, 8.84 m (29.0 ft) SSE
of the centerline of the dirt road, and 0.61 m (2.0 ft) north of a witness post.
 The bench mark is set 0.1 m (0.3 ft) below ground level, crimped to the top of
a stainless steel rod driven 7.6 m (25 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  4 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  2746 J 1981
                         DESIGNATION:          866 2746 J

MONUMENTATION:           Tidal Station disk                    VM#:          592
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The bench mark is a disk set in concrete monument located 111.0 m (364.2 ft) NNW
of bench mark 2746 K 1981, 41.18 m (135.1 ft) SW of the SW corner of a white
concrete block house, 6.22 m (20.4 ft) west of the centerline of the dirt road
leading to the gage site, 1.83 m (6.0 ft) west of a 0.37 m (1.2 ft) diameter
palmetto tree, and 1.04 m (3.4 ft) NW of a witness post with sign.



                         BENCH MARK STAMPING:  2746 K 1981
                         DESIGNATION:          866 2746 K

MONUMENTATION:           Tidal Station disk                    VM#:          593
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The bench mark is a disk set in concrete monument located 93.3 m (306.2 ft)
north of the north corner of a green barn, 16.03 m (52.6 ft) ESE of the
centerline of the dirt road leading to the gage site, 14.63 m (48.0 ft) NNE of a
0.37 m (1.2 ft) diameter palmetto tree, 6.40 m (21.0 ft) south of a 0.37 m (1.2
ft) diameter magnolia tree, and 0.98 m (3.2 ft) east of a witness post with
sign.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  AZ MK 022 024 1981
                         DESIGNATION:          022 024 AZ MK

MONUMENTATION:           Azimuth Mark disk                     VM#:          594
AGENCY:                  South Carolina Geodetic Survey (SCGS) IDB PID#:  DD2905
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID#: DD2905
LATITUDE:   33° 13.7' N (  33.22830)          LONGITUDE:  79° 12.3' W ( -79.20500)


The bench mark is a disk set in a concrete monument located at a telephone pole
near the entrance to the Tom Yawkey Wildlife Center, 16.67 m (54.7 ft) WNW of
the center of the brass plaque commemorating the Tom Yawkey Wildlife Center,
7.74 m (25.4 ft) north of the center of the easternmost 2 m x 2 m (6 ft x 6 ft)
picket fence post, 5.8 m (19 ft) SSW of the centerline of the dirt road leading
to the main gates of the Wildlife Center, 1.68 m (5.5 ft) NE of a metal witness
post with sign, and 1.34 m (4.4 ft) NE of telephone junction box P112 located at
the base of a telephone pole.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  H 137 1979
                         DESIGNATION:          H 137

MONUMENTATION:           Flange-encased Rod                    VM#:          595
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  DD0885
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: DD0885
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.3' W ( -79.20500)


The bench mark is a flange encased rod located near the Coast Guard maintenance
garage, 29.11 m (95.5 ft) west of bench mark WB NO 1 1975, 27.83 m (91.3 ft)
west of the NW corner of the pier, 19.63 m (64.4 ft) NNW of bench mark WB NO 2
1975, 12.13 m (39.8 ft) south of a gas pump, 4.02 m (13.2 ft) north of the NE
corner of the  garage, and 0.42 m (1.4 ft) south of a witness post. The datum
point is the top of a stainless steel rod driven to a depth of 12.5 m (41 ft),
and encased in a 5-inch NGS logo cap.



                         BENCH MARK STAMPING:  WB 17
                         DESIGNATION:          866 2746 WB 17

MONUMENTATION:           Survey disk                           VM#:          597
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The bench mark is a disk located on the Coast Guard property, 18.65 m (61.2 ft)
NE of the NE corner of the maintenance garage, 16.76 m (55.0 ft) NW of the NW
end of the wooden pier, 10.97 m (36.0 ft) east of a gas pump, and 0.90 m (3.0
ft) SE of a witness post.  The bench mark is crimped to the top of a copper-clad
steel rod driven to an unspecified depth, and encased in a PVC pipe and concrete
kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


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


                         BENCH MARK STAMPING:  2746 L 1989
                         DESIGNATION:          866 2746  L

MONUMENTATION:           Tidal Station disk                    VM#:          598
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   33° 14.1' N (  33.23500)          LONGITUDE:  79° 12.2' W ( -79.20330)


The bench mark is a disk located on the Star of South Carolina property near a
corrugated steel building, 46.73 m (153.3 ft) NW of the SW cornerstone of the
northernmost cinderblock wall, 25.91 m (85.0 ft) NNE of the NE corner of the
corrugated steel building, 8.75 m (28.7 ft) west of the centerline of a dirt
road, and 0.46 m (1.5 ft) west of a witness post.  The bench mark is crimped to
the top of a stainless steel rod, driven to unspecified depth.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


                            T I D A L   D A T U M S 


Tidal datums at WINYAH BAY, SOUTH ISLAND PLANTATION based on:

     LENGTH OF SERIES:      17 YEARS
     TIME PERIOD:           January 1979 - December 1995
     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 (09/22/1989)         =  2.812
     MEAN HIGHER HIGH WATER                     MHHW   =  1.305
     MEAN HIGH WATER                            MHW    =  1.212
     North American Vertical Datum              NAVD88 =  0.675
     MEAN TIDE LEVEL                            MTL    =  0.631
     MEAN SEA LEVEL                             MSL    =  0.624
     MEAN LOW WATER                             MLW    =  0.050
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (03/13/1993)         = -1.123

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     WB NO 1 1975                                1.891    0.679
     WB NO 2 1975                                2.019    0.807
     WB NO 4 1975                                1.776    0.564
     WB NO 5 1975                                1.420    0.208
     2746 G 1978                                 1.769    0.557
     2746 J 1981                                 1.443    0.231
     2746 K 1981                                 2.344    1.132
     AZ MK 022 024 1981                          1.271    0.059
     H 137 1979                                  1.625    0.413
     WB 17                                       1.751    0.539
     2746 L 1989                                 1.596    0.384


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of  9

                                                                                
Station ID: 8662746                         PUBLICATION DATE:  05/06/2003
Name:       WINYAH BAY, SOUTH ISLAND PLANTATION               
            SC
NOAA Chart: 11532                           Latitude:   33° 14.1' N (  33.23500)
USGS Quad:  SANTEE POINT                    Longitude:  79° 12.2' W ( -79.20330)


                             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 8662746 WINYAH BAY, SOUTH ISLAND PLANTATION, SC

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services