U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8669601                         PUBLICATION DATE:  04/01/2004
Name:       PINE ISLAND, RAMSHORN CREEK                       
            SC
NOAA Chart: 11512                           Latitude:   32°  7.3' N (  32.12170)
USGS Quad:  FORT PULASKI                    Longitude:  80° 53.9' W ( -80.89830)


To reach the tidal bench marks by boat from the ramp at Harbour Town, Hilton
Head Island, proceed NW across Calibogue Sound to Cooper River, then proceed SW
on Cooper River for 6.0 km (3.7 mi) to Ramshorn Creek, then proceed south on
Ramshorn Creek for 1.3 km (0.8 mi)  to Pine Island.  The bench marks are located
on Pine Island.  The tide gage and staff were located on an offshore platform on
the west side of the creek.  Note: Care should be taken to anchor the boat
offshore of the clay bank, which is exposed at low water.  The wake from a
passing vessel can literally lift a small craft onto these banks, causing it to
become stranded.


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


                 PRIMARY BENCH MARK STAMPING:  9601 D 1980
                         DESIGNATION:          866 9601 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4673
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   32°  7.3' N (  32.12170)          LONGITUDE:  80° 53.9' W ( -80.89830)


The primary bench mark is a disk located 8.96 m (29.4 ft) north of a palmetto
tree on the bluff edge, 6.28 m (20.6 ft) WNW of a 0.46 m (1.5 ft) diameter pine
tree, 5.97 m (19.6 ft) ESE of a double oak tree, 2.41 m (7.9 ft) ESE of a
witness post, and 0.91 m (3.0 ft) south of a witness post with a sign.  The
bench mark is set 6 cm (0.2 ft) below ground level, crimped to the top of a
stainless steel rod driven 12.2 m (40 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: 8669601                         PUBLICATION DATE:  04/01/2004
Name:       PINE ISLAND, RAMSHORN CREEK                       
            SC
NOAA Chart: 11512                           Latitude:   32°  7.3' N (  32.12170)
USGS Quad:  FORT PULASKI                    Longitude:  80° 53.9' W ( -80.89830)


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


                         BENCH MARK STAMPING:  9601 A 1980
                         DESIGNATION:          866 9601 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4672
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   32°  7.3' N (  32.12170)          LONGITUDE:  80° 53.9' W ( -80.89830)


The bench mark is a disk located 18 m (59 ft) SE of a cluster of five oak trees,
8.84 m (29.0 ft) NE of a 0.61 m (2.0 ft) diameter oak tree, 5.12 m (16.8 ft) WNW
of the bluff edge, and 0.55 m (1.8 ft) SE of a metal witness post with sign. 
The bench mark is set 6 cm (0.2 ft) below ground level, crimped to the top of a
stainless steel rod driven 12.2 m (40 ft) to refusal, and encased in a 4-inch
PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  9601 F 1981
                         DESIGNATION:          866 9601 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4674
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32°  7.3' N (  32.12170)          LONGITUDE:  80° 53.9' W ( -80.89830)


The bench mark is a disk set in a concrete monument, 68.28 m (224.0 ft) ENE of
bench mark 9601 G 1981, 42.82 m (140.5 ft) WSW of bench mark 9601 A 1980, 3.38 m
(11.1 ft) south of 0.30 m (1.0 ft) diameter oak tree, and 0.52 m (1.7 ft) NE of
a metal witness post with sign. 

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8669601                         PUBLICATION DATE:  04/01/2004
Name:       PINE ISLAND, RAMSHORN CREEK                       
            SC
NOAA Chart: 11512                           Latitude:   32°  7.3' N (  32.12170)
USGS Quad:  FORT PULASKI                    Longitude:  80° 53.9' W ( -80.89830)


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


                         BENCH MARK STAMPING:  9601 G 1981
                         DESIGNATION:          866 9601 G TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4675
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32°  7.3' N (  32.12170)          LONGITUDE:  80° 53.9' W ( -80.89830)


The bench mark is a disk set in a concrete monument, 52.64 m (172.7 ft) NE of
bench mark 9601 H 1981, 3.11 m (10.2 ft) SE of 0.55 m (1.8 ft) diameter forked
trunk oak tree, and 0.64 m (2.1 ft) east of a metal witness post with sign. 



                         BENCH MARK STAMPING:  9601 H 1981
                         DESIGNATION:          866 9601 H TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         4676
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32°  7.3' N (  32.12170)          LONGITUDE:  80° 53.9' W ( -80.89830)


The bench mark is a disk set in a concrete monument, 45.57 m (149.5 ft) NNE of
bench mark 9601 D 1980, 13.72 m (45.0 ft) ESE of 0.61 m (2.0 ft) diameter oak
tree, 7.10 m (23.3 ft) WNW of a 0.61 m (2.0 ft) diameter loblolly pine tree, and
1.19 m (3.9 ft) NE of a metal witness post with sign. 

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

                                                                                
Station ID: 8669601                         PUBLICATION DATE:  04/01/2004
Name:       PINE ISLAND, RAMSHORN CREEK                       
            SC
NOAA Chart: 11512                           Latitude:   32°  7.3' N (  32.12170)
USGS Quad:  FORT PULASKI                    Longitude:  80° 53.9' W ( -80.89830)


                            T I D A L   D A T U M S 


Tidal datums at PINE ISLAND, RAMSHORN CREEK based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           September 1981 - November 1981
     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   =  2.359
     MEAN HIGH WATER                            MHW    =  2.245
     MEAN SEA LEVEL                             MSL    =  1.233
     MEAN TIDE LEVEL                            MTL    =  1.153
     MEAN LOW WATER                             MLW    =  0.061
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     9601 D 1980                                 2.835    0.590
     9601 A 1980                                 3.452    1.207
     9601 F 1981                                 3.417    1.172
     9601 G 1981                                 3.448    1.203
     9601 H 1981                                 3.322    1.077


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

                                                                                
Station ID: 8669601                         PUBLICATION DATE:  04/01/2004
Name:       PINE ISLAND, RAMSHORN CREEK                       
            SC
NOAA Chart: 11512                           Latitude:   32°  7.3' N (  32.12170)
USGS Quad:  FORT PULASKI                    Longitude:  80° 53.9' W ( -80.89830)


                             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.