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

                                                                                
Station ID: 8663535                         PUBLICATION DATE:  03/09/2004
Name:       QUINBY BRIDGE, QUINBY CREEK                       
            SC
NOAA Chart:                                 Latitude:   33°  5.7' N (  33.09500)
USGS Quad:  HUGER                           Longitude:  79° 48.5' W ( -79.80830)


To reach the tidal bench marks from the intersection of State Highway 41 and
County Road S-8-98 (Cainhoy Road) in Huger, proceed 0.2 km (0.1 mi) SW on County
Road S-8-98 to the bridge over Quinby Creek.  The tidal bench marks are on the
bridge and along County Road S-8-98 north of the bridge.  The tide gage and
staff were on the east side of the bridge.


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


                 PRIMARY BENCH MARK STAMPING:  866 C 3535 1976
                         DESIGNATION:          866 3535 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3989
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1205
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33°  5.7' N (  33.09500)          LONGITUDE:  79° 48.5' W ( -79.80830)


The primary bench mark is a disk located near an historical marker at the east
end of a boat ramp parking area at the Quinby Creek bridge, 59.04 m (193.7 ft)
ENE of the NE corner of the bridge, 8.66 m (28.4 ft) SSE of a 1 m (3 ft)
diameter twin trunk oak tree, 8.35 m (27.4 ft) NNW of the centerline of County
Road S-8-98, 1.46 m (4.8 ft) SW of an historical marker, and 0.88 m (2.9 ft) NNE
of a metal witness post.  The bench mark is set 3 cm (1 ft) below road level,
crimped to the top of a copper-clad steel rod driven 7.0 m (23 ft) to refusal,
and encased in a 5-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: 8663535                         PUBLICATION DATE:  03/09/2004
Name:       QUINBY BRIDGE, QUINBY CREEK                       
            SC
NOAA Chart:                                 Latitude:   33°  5.7' N (  33.09500)
USGS Quad:  HUGER                           Longitude:  79° 48.5' W ( -79.80830)


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


                         BENCH MARK STAMPING:  3535 A 1976
                         DESIGNATION:          866 3535 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3987
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1203
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   33°  5.7' N (  33.09500)          LONGITUDE:  79° 48.5' W ( -79.80830)


The bench mark is a disk set in the south concrete abutment of the Quinby Creek
bridge, 7.68 m (25.2 ft) ENE of the SW corner of the abutment across the road,
3.81 m (12.5 ft) ESE of the centerline of County Road S-8-98, 1.68 m (5.5 ft)
NNE of the SE corner of the bridge, and 0.3 m (1 ft) above road level.



                         BENCH MARK STAMPING:  3535 B 1976
                         DESIGNATION:          866 3535 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3988
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1204
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   33°  5.7' N (  33.09500)          LONGITUDE:  79° 48.5' W ( -79.80830)


The bench mark is a disk set in the north concrete abutment of the Quinby Creek
bridge, 28.32 m (92.9 ft) NNW of bench mark 3535 A 1976, 7.62 m (25.0 ft) WSW of
the abutment across the road, 3.81 m (12.5 ft) west of the centerline of County
Road S-8-98, 1.28 m (4.2 ft) SW of the NW bridge abutment, and 0.3 m (1 ft)
above road level.

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

                                                                                
Station ID: 8663535                         PUBLICATION DATE:  03/09/2004
Name:       QUINBY BRIDGE, QUINBY CREEK                       
            SC
NOAA Chart:                                 Latitude:   33°  5.7' N (  33.09500)
USGS Quad:  HUGER                           Longitude:  79° 48.5' W ( -79.80830)


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


                         BENCH MARK STAMPING:  3535 F 1982
                         DESIGNATION:          866 3535 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3991
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1206
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   33°  5.7' N (  33.09500)          LONGITUDE:  79° 48.3' W ( -79.80500)


The bench mark is a disk located in the SW corner of the intersection of State
Highway 41 and County Road S-8-98, 29.32 m (96.2 ft) NNE of bench mark VERT 8
092 1984, 20.42 m (67.0 ft) SSE of the centerline of County Road S-8-98, 15.91 m
(52.2 ft) west of the centerline of State Highway 41, 10.88 m (35.7 ft) ESE of
the NE corner of a 1 m (4 ft) square concrete storm drain, and 2.44 m (8.0 ft)
NNW of a 1 m (3 ft) diameter pine tree.  The bench mark is set 3 cm (1 ft) below
road level, crimped to the top of a stainless steel rod driven 8.2 m (27 ft) to
refusal, and encased in a 5-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  VERT 8 092 1984
                         DESIGNATION:          8 092

MONUMENTATION:           Bench Mark disk                       VM#:         3992
AGENCY:                  South Carolina Geodetic Society (SCGS) IDB PID#:  DD1207
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   33°  5.7' N (  33.09500)          LONGITUDE:  79° 48.3' W ( -79.80500)


The bench mark is a disk set in a concrete monument near a power pole in the SW
corner of the intersection of State Highway 41 and County Road S-8-98, 48.34 m
(158.6 ft) SSW of the centerline of County Road S-8-98, 20.18 m (66.2 ft) WNW of
the centerline of State Highway 41, 7.53 m (24.7 ft) SSW of a blazed 0.61 m (2.0
ft) diameter pine tree, 1.92 m (6.3 ft) NNE of the power pole, 0.49 m (1.6 ft)
ESE of a witness post, and 0.61 m (2.0 ft) below highway level.

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

                                                                                
Station ID: 8663535                         PUBLICATION DATE:  03/09/2004
Name:       QUINBY BRIDGE, QUINBY CREEK                       
            SC
NOAA Chart:                                 Latitude:   33°  5.7' N (  33.09500)
USGS Quad:  HUGER                           Longitude:  79° 48.5' W ( -79.80830)


                            T I D A L   D A T U M S 


Tidal datums at QUINBY BRIDGE, QUINBY CREEK based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           September 1976 - December 1976
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8663665 RICHMOND PLANTATION, E. BR. COOPER RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.981
     MEAN HIGH WATER                            MHW    =  0.921
     MEAN SEA LEVEL                             MSL    =  0.562
     MEAN TIDE LEVEL                            MTL    =  0.502
     North American Vertical Datum              NAVD88 =  0.182
     MEAN LOW WATER                             MLW    =  0.082
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     866 C 3535 1976                             1.689    0.768
     3535 A 1976                                 2.245    1.324
     3535 B 1976                                 2.246    1.325
     3535 F 1982                                 6.521    5.600
     VERT 8 092 1984                             6.457    5.536


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

                                                                                
Station ID: 8663535                         PUBLICATION DATE:  03/09/2004
Name:       QUINBY BRIDGE, QUINBY CREEK                       
            SC
NOAA Chart:                                 Latitude:   33°  5.7' N (  33.09500)
USGS Quad:  HUGER                           Longitude:  79° 48.5' W ( -79.80830)


                             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.