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Bench Mark Sheet for 8668701, Purrysburg Landing, Savannah 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8668701                         PUBLICATION DATE:  05/12/2004
Name:       PURRYSBURG LANDING, SAVANNAH RIVER                
            SC
NOAA Chart: 11514                           Latitude:   32° 18.2' N (  32.30330)
USGS Quad:  HARDEEVILLE                     Longitude:  81°  7.3' W ( -81.12170)


To reach the tidal bench marks from the intersection of U.S. Highway 17 and
State Highway 46 in Hardeeville, proceed NW on State Highway 46 for 0.5 km (0.3
mi) to U.S. Highway 321, then proceed straight through the intersection and onto
County Road S-27-31 (Church Rd) for 3.5 km (2.2 mi) to the end of the road, then
turn right and proceed north on County Road S-27-34 (Purrysburg Road) for 0.6 km
(0.4 mi) to the entrance of Purrysburg Fishing Camp, then turn left into the
entrance and proceed 0.3 km (0.2 mi) to the camp.  The bench marks are near the
bait shop and along the road leading to the fishing camp.  The tide gage and
staff were located on the camp's dock behind the bait shop and house.


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


                 PRIMARY BENCH MARK STAMPING:  8701 D 1979
                         DESIGNATION:          866 8701 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4518
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK1994
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   32° 18.3' N (  32.30500)          LONGITUDE:  81°  7.2' W ( -81.12000)


The primary bench mark is a disk located at the NW corner of the intersection of
County Road S-27-34 and the dirt road leading to Purrysburg Fishing Camp, 18.32
m (60.1 ft) NNE of a 0.3 m (1.0 ft) diameter pine tree with a sign "Drive Slow
Or Stay The Hell Out", 11.77 m (38.6 ft) west of County Road S-27-34, 8.90 m
(29.2 ft) NNW of a stop sign, 5.70 m (18.7 ft) NNE of the centerline of the dirt
road leading to the tide gage, and 1.49 m (4.9 ft) east of a 0.61 m (2.0 ft)
diameter pine tree.  The bench mark is set 6 cm (0.2 ft) below ground level,
crimped to the top of a stainless steel rod driven 9.1 m (30 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  5

                                                                                
Station ID: 8668701                         PUBLICATION DATE:  05/12/2004
Name:       PURRYSBURG LANDING, SAVANNAH RIVER                
            SC
NOAA Chart: 11514                           Latitude:   32° 18.2' N (  32.30330)
USGS Quad:  HARDEEVILLE                     Longitude:  81°  7.3' W ( -81.12170)


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


                         BENCH MARK STAMPING:  8701 E 1979
                         DESIGNATION:          866 8701 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4519
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK1993
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   32° 18.2' N (  32.30330)          LONGITUDE:  81°  7.2' W ( -81.12000)


The bench mark is a disk located on the east side of County Road S-27-34, south
of the dirt road leading to Purrysburg Fishing Camp, 61.36 m (201.3 ft) SSE of
bench mark 8701 D 1979, 22 m (72 ft) ENE of telephone junction box #EE 6-126-36,
9.75 m (32.0 ft) ESE of the centerline of County Road S-27-34, and 2.29 m (7.5
ft) north of a 0.3 m (1.0 ft) diameter maple tree.  The bench mark is set 6 cm
(0.2 ft) below ground level crimped to the top of a stainless steel rod driven
9.1 m (30 ft) to refusal, and encased in a 4-inch PVC pipe and concrete
kickblock.



                         BENCH MARK STAMPING:  8701 F 1979
                         DESIGNATION:          866 8701 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4520
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK1992
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   32° 18.1' N (  32.30170)          LONGITUDE:  81°  7.2' W ( -81.12000)


The bench mark is a disk located on the west side of County Road S-27-34, 55 m
(180 ft) SSW of bench mark 8701 E 1979, 36.61 m (120.1 ft) south of telephone
junction box #EE-6-126-136, 10.36 m (34.0 ft) west of the centerline of County
Road S-27-34, 3.02 m (9.9 ft) SW of a witness sign on a 0.61 m (2.0 ft) diameter
oak tree.  The bench mark is set 3 cm (0.1 ft) below ground level, crimped to
the top of a stainless steel rod driven 9.4 m (31 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  5

                                                                                
Station ID: 8668701                         PUBLICATION DATE:  05/12/2004
Name:       PURRYSBURG LANDING, SAVANNAH RIVER                
            SC
NOAA Chart: 11514                           Latitude:   32° 18.2' N (  32.30330)
USGS Quad:  HARDEEVILLE                     Longitude:  81°  7.3' W ( -81.12170)


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


                         BENCH MARK STAMPING:  8701 G 1981
                         DESIGNATION:          866 8701 G TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4521
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK1996
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32° 18.2' N (  32.30330)          LONGITUDE:  81°  7.3' W ( -81.12170)


The bench mark is a disk set flush in a concrete monument located at the west
end of the driveway by a spigot, 23 m (76 ft) ESE of the river edge, 18.01 m
(59.1 ft) WNW of the service pole with light #E-88-76-5PPH-630, 13.87 m (45.5
ft) SSW of the SW corner of the porch of the red house belonging to Mr. Curtis,
12.50 m (41.0 ft) south of a 1.28 m (4.2 ft) diameter oak tree, 3.20 m (10.5 ft)
ESE of the water spigot. 



                         BENCH MARK STAMPING:  8701 H 1981
                         DESIGNATION:          866 8701 H TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4522
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CK1995
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32° 18.2' N (  32.30330)          LONGITUDE:  81°  7.3' W ( -81.12170)


The bench mark is a disk set flush in a concrete monument set at the north edge
of the yard of the house at the west end of the driveway, 60.96 m (200.0 ft)
north of the centerline of the dirt entrance road, 35.23 m (115.6 ft) NNE of a
service pole with a light, 7.47 m (24.5 ft) NNW  of the NE corner of a metal
shed, and 1.89 m (6.2 ft) east of the center of the eastern face of the concrete
block garden wall.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8668701                         PUBLICATION DATE:  05/12/2004
Name:       PURRYSBURG LANDING, SAVANNAH RIVER                
            SC
NOAA Chart: 11514                           Latitude:   32° 18.2' N (  32.30330)
USGS Quad:  HARDEEVILLE                     Longitude:  81°  7.3' W ( -81.12170)


                            T I D A L   D A T U M S 


Tidal datums at PURRYSBURG LANDING, SAVANNAH RIVER based on:

     LENGTH OF SERIES:      6 MONTHS
     TIME PERIOD:           July 1980 - December 1980
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8670870 FORT PULASKI, SAVANNAH RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.006
     MEAN HIGH WATER                            MHW    =  0.949
     MEAN SEA LEVEL                             MSL    =  0.520
     MEAN TIDE LEVEL                            MTL    =  0.488
     MEAN LOW WATER                             MLW    =  0.026
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.518

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8701 D 1979                                 4.520    3.571
     8701 E 1979                                 4.218    3.269
     8701 F 1979                                 4.529    3.580
     8701 G 1981                                 4.608    3.659
     8701 H 1981                                 4.928    3.979


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

                                                                                
Station ID: 8668701                         PUBLICATION DATE:  05/12/2004
Name:       PURRYSBURG LANDING, SAVANNAH RIVER                
            SC
NOAA Chart: 11514                           Latitude:   32° 18.2' N (  32.30330)
USGS Quad:  HARDEEVILLE                     Longitude:  81°  7.3' W ( -81.12170)


                             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 8668701 Purrysburg Landing, Savannah River, SC

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