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

                                                                                
Station ID: 8661609                         PUBLICATION DATE:  06/16/2004
Name:       OAKS CR. INLET, MURRELLS INLET                    
            SC
NOAA Chart: 11535                           Latitude:   33° 31.8' N (  33.53000)
USGS Quad:  BROOKGREEN                      Longitude:  79°  2.6' W ( -79.04330)


To reach the tidal bench marks from the surfaced ramp in the town of Murrells
Inlet, proceed by boat south on the dredged channel for about 4.3 km (2.3 nm) to
the entrance of Oaks Creek, continue west on Oaks Creek for 0.8 km (0.4 nm) to
the NE end of Drunken Jack Island.  The tidal bench marks are along the NE side
and end of Drunken Jack Island.  The tide gage and staff were on a small
offshore structure in the middle of the creek.


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


                 PRIMARY BENCH MARK STAMPING:  O.C.I. NO 2 1975
                         DESIGNATION:          866 1609 O.C.I. NO 2

MONUMENTATION:           Tidal Station disk                    VM#:         3839
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 31.8' N (  33.53000)          LONGITUDE:  79°  2.6' W ( -79.04330)


The primary bench mark is a disk located on an irregularly shaped mound on the
NE end of Drunken Jack Island, 27 m (90 ft) south of Oaks Creek, 27 m (90 ft)
east of a slough, and 2.10 m (6.9 ft) east of a metal witness post with sign. 
The bench mark is set 1 m (2 ft) above marsh level, crimped to the top of a
copper-clad steel rod driven 14.0 m (46 ft) to refusal, and encased in a 4-inch
PVC pipe.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8661609                         PUBLICATION DATE:  06/16/2004
Name:       OAKS CR. INLET, MURRELLS INLET                    
            SC
NOAA Chart: 11535                           Latitude:   33° 31.8' N (  33.53000)
USGS Quad:  BROOKGREEN                      Longitude:  79°  2.6' W ( -79.04330)


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


                         BENCH MARK STAMPING:  O.C.I. NO 3 1975
                         DESIGNATION:          866 1609 O.C.I. NO 3

MONUMENTATION:           Tidal Station disk                    VM#:         3840
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 31.8' N (  33.53000)          LONGITUDE:  79°  2.6' W ( -79.04330)


The bench mark is a disk located on an irregularly shaped mound on the NE end of
Drunken Jack Island, 165 m (540 ft) SSE of bench mark O.C.I. NO 2 1975, 52 m
(172 ft) WNW of bench mark O.C.I. NO 4 1975, 46 m (150 ft) south of a slough, 37
m (120 ft) NE of the tree line, and 2.35 m (7.7 ft) SW of a metal witness post
with sign.  The bench mark is set 1 m (2 ft) above marsh level, crimped to the
top of a copper-clad steel rod driven 12.2 m (40 ft) to refusal, and encased in
a 4-inch PVC pipe.



                         BENCH MARK STAMPING:  O.C.I. NO 4 1975
                         DESIGNATION:          866 1609 O.C.I. NO 4

MONUMENTATION:           Tidal Station disk                    VM#:         3841
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 31.8' N (  33.53000)          LONGITUDE:  79°  2.6' W ( -79.04330)


The bench mark is a disk located on the NE side of Drunken Jack Island, 192 m
(630 ft) south of Oaks Creek, 134 m (438 ft) ESE of bench mark O.C.I. NO 5 1975,
 9 m (30 ft) east of the tree line,  5 m (15 ft) SSW of a lone scrub pine tree,
and 3.54 m (11.6 ft) west of a metal witness post.  The bench mark is crimped to
the top of a copper-clad steel rod driven 15.2 m (50 ft) to substantial
resistance, and encased in a 4-inch PVC pipe.

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

                                                                                
Station ID: 8661609                         PUBLICATION DATE:  06/16/2004
Name:       OAKS CR. INLET, MURRELLS INLET                    
            SC
NOAA Chart: 11535                           Latitude:   33° 31.8' N (  33.53000)
USGS Quad:  BROOKGREEN                      Longitude:  79°  2.6' W ( -79.04330)


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


                         BENCH MARK STAMPING:  O.C.I. NO 5 1975
                         DESIGNATION:          866 1609 O.C.I. NO 5

MONUMENTATION:           Tidal Station disk                    VM#:         3842
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper pipe                           OPUS PID:        
LATITUDE:   33° 31.8' N (  33.53000)          LONGITUDE:  79°  2.6' W ( -79.04330)


The bench mark is a disk brazed to the top of a 1.07 m (3.5 ft) long 2-inch
copper pipe in the center of a 15 m (50 ft) diameter low mound on the NE side of
Drunken Jack Island,  91 m (300 ft) west of bench mark O.C.I. NO 3 1975, 64 m
(210 ft) south of a slough, 27 m (90 ft) north of the tree line, 1.62 m (5.3 ft)
east of a metal witness post with sign, 1.52 m (5.0 ft) east of a lone pine
tree, and 0.15 m (0.5 ft) above grade.

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

                                                                                
Station ID: 8661609                         PUBLICATION DATE:  06/16/2004
Name:       OAKS CR. INLET, MURRELLS INLET                    
            SC
NOAA Chart: 11535                           Latitude:   33° 31.8' N (  33.53000)
USGS Quad:  BROOKGREEN                      Longitude:  79°  2.6' W ( -79.04330)


                            T I D A L   D A T U M S 


Tidal datums at OAKS CR. INLET, MURRELLS INLET based on:

     LENGTH OF SERIES:      7 MONTHS
     TIME PERIOD:           May 1975 - November 1975
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8661559 SMITH'S DOCK, MURRELLS INLET


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.474
     MEAN HIGH WATER                            MHW    =  1.357
     MEAN SEA LEVEL                             MSL    =  0.715
     MEAN TIDE LEVEL                            MTL    =  0.706
     MEAN LOW WATER                             MLW    =  0.055
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     O.C.I. NO 2 1975                            1.879    0.522
     O.C.I. NO 3 1975                            1.634    0.277
     O.C.I. NO 4 1975                            1.936    0.579
     O.C.I. NO 5 1975                            2.285    0.928


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

                                                                                
Station ID: 8661609                         PUBLICATION DATE:  06/16/2004
Name:       OAKS CR. INLET, MURRELLS INLET                    
            SC
NOAA Chart: 11535                           Latitude:   33° 31.8' N (  33.53000)
USGS Quad:  BROOKGREEN                      Longitude:  79°  2.6' W ( -79.04330)


                             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.