U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


To reach the tidal bench marks from the intersection of East Bay Street and the
crosstown highway at the south foot of the northbound Cooper River Bridge,
proceed SE on East Bay Street for 2.6 km (1.6 mi).  Turn left onto Market Street
for 0.2 km (0.1 mi) to Concord Street.  Turn right and travel 0.08 km (0.05 mi)
to the drive of South Carolina Port Authority.  Turn left and follow the drive
to a dock.  The bench marks are in the vicinity of U.S. Custom House, along East
Bay Street, and along Broad Street.  The tide gage and staff are on the south
end of the dock.


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


                 PRIMARY BENCH MARK STAMPING:  NO 13 1928 ELEV 8.264 FT
                         DESIGNATION:          866 5530 TIDAL 13

MONUMENTATION:           Tidal Station disk                    VM#:          611
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0085
SETTING CLASSIFICATION:  Concrete dock                         OPUS PID#: CJ0085
LATITUDE:   32° 46.9' N (  32.78169)          LONGITUDE:  79° 55.5' W ( -79.92500)


The primary bench mark is a disk set near the east end of the concrete portion
of the dock and beyond the guard railway of a concrete pier landing on the
approach walkway to the Ports Authority Union Pier Loading Building (note:  key
must be obtained to access the walkway), 18.14 m (59.5 ft) east of the north
gate post at the walkway entrance, 5.46 m (17.9 ft) south of the north edge of
the concrete dock, 2.41 m (7.9 ft) north of the north edge of the concrete curb
at the walkway to the loading building, and 0.40 m (1.3 ft) west of the east
edge of the concrete dock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          9.3=EXTRA
                         ALIAS:                NO STAMPING 1

MONUMENTATION:           Chiseled Cross                        VM#:          613
AGENCY:                  Unknown                               IDB PID#:  CJ0091
SETTING CLASSIFICATION:   Step                                 OPUS PID:        
LATITUDE:   32° 46.9' N (  32.78169)          LONGITUDE:  79° 55.5' W ( -79.92500)


The bench mark is a chiseled cross in the top of the south end of the bottom
step on the east side entrance of the U.S. Customhouse, at the intersection of
Market and Concord Streets, 0.3 m (1 ft) south of an iron railing fence, 0.09 m
(0.3 ft) north of south end of step, and about 0.15 m (0.5 ft) above walk.



                         BENCH MARK STAMPING:  9.311 1918
                         DESIGNATION:          9

MONUMENTATION:           Traverse Station disk                 VM#:          614
AGENCY:                  US Geological Survey (USGS)           IDB PID#:  CJ0084
SETTING CLASSIFICATION:  Granite step                          OPUS PID:        
LATITUDE:   32° 46.8' N (  32.78000)          LONGITUDE:  79° 55.5' W ( -79.92500)


The bench mark is a disk set in the north end of the bottom granite step at the
east entrance to the U.S. Customhouse, at the intersection of Market and Concord
Streets, 24.57 m (80.6 ft) west of the center of Concord Street, and 0.30 m (1.0
ft) south of the wrought iron railing.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  7 1921 ELEV 13.612 FT
                         DESIGNATION:          866 5530 TIDAL 7

MONUMENTATION:           Tidal Station disk                    VM#:          615
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0090
SETTING CLASSIFICATION:  Window ledge                          OPUS PID:        
LATITUDE:   32° 46.8' N (  32.78000)          LONGITUDE:  79° 55.5' W ( -79.92500)


The bench mark is a disk set in the top of the east end of a window ledge at the
U.S. Customhouse at the intersection of Market and East Bay Streets, in the
second basement window west of the SE corner of the east wing of the building,
3.51 m (11.5 ft) west of the centerline of the steps on the south side of the
building and 1.40 m (4.6 ft) above ground level.



                         BENCH MARK STAMPING:  8 1921 ELEV 11.109 FT
                         DESIGNATION:          866 5530 TIDAL 8

MONUMENTATION:           Tidal Station disk                    VM#:          616
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0094
SETTING CLASSIFICATION:  Stone doorsill                        OPUS PID:        
LATITUDE:   32° 46.7' N (  32.77831)          LONGITUDE:  79° 55.6' W ( -79.92669)


The bench mark is a disk set flush in the north corner of a stone doorsill at
the entrance to 185 East Bay Street, on the west side of East Bay Street across
from the driveway between 184 and 186 East Bay Street, 4.21 m (13.8 ft) SSW of
an unnumbered light pole, and 2.87 m (9.4 ft) south of the NE corner of a store
front.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  9 1921 ELEV 11.394 FT
                         DESIGNATION:          866 5530 TIDAL 9

MONUMENTATION:           Tidal Station disk                    VM#:          617
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0095
SETTING CLASSIFICATION:  Stone step                            OPUS PID:        
LATITUDE:   32° 46.7' N (  32.77831)          LONGITUDE:  79° 55.6' W ( -79.92669)


The bench mark is a disk set flush at the south end of the top curved step of
the East Bay Trading Company Restaurant, at the intersection of East Bay and
Queen Streets, 9.75 m (32.0 ft) west of the centerline of East Bay Street, 6.80
m (22.3 ft) south of the centerline of Queen Street, and 4.97 m (16.3 ft) WNW of
a fire hydrant.



                         BENCH MARK STAMPING:  11 1921 ELEV 14.108 FT
                         DESIGNATION:          866 5530 TIDAL 11

MONUMENTATION:           Tidal Station disk                    VM#:          618
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0152
SETTING CLASSIFICATION:  Stone doorsill                        OPUS PID:        
LATITUDE:   32° 46.6' N (  32.77669)          LONGITUDE:  79° 55.6' W ( -79.92669)


The bench mark is a disk set flush on the east side of a stone doorsill of the
Peoples Office Building at 18 Broad Street, at the junction of Broad and State
Streets, 19.81 m (65.0 ft) west of the centerline of State Street, 11.03 m (36.2
ft) north of the centerline of Broad Street, 1.28 m (4.2 ft) east of the
centerline of the entrance to the building, and 0.15 m (0.5 ft) above Broad
Street.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  12 1921 ELEV 16.552 FT
                         DESIGNATION:          866 5530 TIDAL 12

MONUMENTATION:           Tidal Station disk                    VM#:          619
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0098
SETTING CLASSIFICATION:  Step                                  OPUS PID:        
LATITUDE:   32° 46.6' N (  32.77669)          LONGITUDE:  79° 55.9' W ( -79.93169)


The bench mark is a disk set flush in the top step of the northernmost Meeting
Street entrance to the old Post Office, at the intersection of Broad and Meeting
Streets, 17.22 m (56.5 ft) south of the centerline of Broad Street, 11.28 m
(37.0 ft) west of the centerline of Meeting Street, 0.67 m (2.2 ft) north of the
center of the entrance door, and 1.68 m (5.5 ft) above Broad Street.



                         BENCH MARK STAMPING:  NO 14 1928 RESET ELEV 8.327 FT
                         DESIGNATION:          866 5530 TIDAL 14 RESET

MONUMENTATION:           Tidal Station disk                    VM#:          620
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0089
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   32° 46.8' N (  32.78000)          LONGITUDE:  79° 55.5' W ( -79.92500)


The bench mark is a disk set in a granite retaining wall at the boat slip across
Concord Street from the east entrance to the U.S. Customhouse, near the southern
entrance to the South Carolina Port Authority Terminal, 11.13 m (36.5 ft) east
of the centerline of Concord Street, 8.96 m (62.2 ft) north of power pole No.
320450, 1.10 m (3.6 ft) east of the west edge of the retaining wall, 0.43 m (1.4
ft) west of the east edge of the retaining wall, and 0.15 m (0.5 ft) above
Concord Street.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  U 16 1933 9.117
                         DESIGNATION:          U 16

MONUMENTATION:           Bench Mark disk                       VM#:          622
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0081
SETTING CLASSIFICATION:  Building                              OPUS PID:        
LATITUDE:   32° 46.8' N (  32.78000)          LONGITUDE:  79° 55.6' W ( -79.92669)


The bench mark is a disk set vertically in a brick wall near the east corner of
the L.A. Grill Restaurant, at the intersection of East Bay and North Market
Streets, 3.29 m (10.8 ft) north of the north curb of North Market Street,  0.64
m (2.1 ft) west of the east corner of a brick building entrance way, and 1.04 m
(3.4 ft) above the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  PORT 1962
                         DESIGNATION:          PORT

MONUMENTATION:           Survey disk                           VM#:          623
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  CJ0326
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID#: CJ0326
LATITUDE:   32° 46.8' N (  32.78078)          LONGITUDE:  79° 55.4' W ( -79.92364)


The bench mark is a disk set flush on the SE edge of the passenger terminal pier
of the South Carolina Port Authority, 3.08 m (10.1 ft) SSE of the SE corner of
the 3x3 m (9x9 ft) concrete block building housing the U.S. Department of
Commerce National Ocean Service Tide Station, 1.80 m (5.9 ft) NE of the SW edge
of the pier, and 1.25 m (4.1 ft) NW of the SE edge of the pier.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


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


                         BENCH MARK STAMPING:  10.945
                         DESIGNATION:          866 5530 TIDAL BASIC
                         ALIAS:                BASIC

MONUMENTATION:           Bench Mark disk                       VM#:          624
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0093
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   32° 46.8' N (  32.78000)          LONGITUDE:  79° 55.5' W ( -79.92500)


The bench mark is a disk set in an 18-inch concrete post near the west entrance
steps to the U.S. Custom House, 33.50 m (109.9 ft) east of the center of East
Bay Street, 11.52 m (37.8 ft) ESE of the southernmost of two flag poles, 9.54 m
(31.3 ft) south of the south face of the large landing at the west entrance
steps, 4.18 m (13.7 ft) north of the north edge of the granite curbing of a
grassy area, 3.26 m (10.7 ft) WNW of a 0.27 m (0.9 ft) palmetto tree, and
projecting 0.67 m (2.2 ft). The west face of the post has formation of colored
rocks spelling United States Coast and Geodetic Survey Basic Bench  Mark.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


                            T I D A L   D A T U M S 


Tidal datums at CHARLESTON, COOPER RIVER ENTRANCE based on:

     LENGTH OF SERIES:      19 YEARS
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (09/21/1989)         =  3.817
     MEAN HIGHER HIGH WATER                     MHHW   =  1.757
     MEAN HIGH WATER                            MHW    =  1.648
     North American Vertical Datum              NAVD88 =  0.957
     MEAN SEA LEVEL                             MSL    =  0.891
     MEAN TIDE LEVEL                            MTL    =  0.853
     MEAN LOW WATER                             MLW    =  0.057
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (03/13/1993)         = -1.245

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 13 1928 ELEV 8.264 FT                    3.177    1.529
     9.3=EXTRA                                   3.496    1.848
     9.311 1918                                  3.499    1.851
     7 1921 ELEV 13.612 FT                       4.812    3.163
     8 1921 ELEV 11.109 FT                       4.054    2.406
     9 1921 ELEV 11.394 FT                       4.126    2.478
     11 1921 ELEV 14.108 FT                      4.953    3.304
     12 1921 ELEV 16.552 FT                      5.711    4.062
     NO 14 1928 RESET ELEV 8.327 FT              3.188    1.539
     U 16 1933 9.117                             3.443    1.794
     PORT 1962                                   3.491    1.842
     10.945                                      3.983    2.334


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 10 of 10

                                                                                
Station ID: 8665530                         PUBLICATION DATE:  04/29/2003
Name:       CHARLESTON, COOPER RIVER ENTRANCE                 
            SC
NOAA Chart: 11524                           Latitude:   32° 46.9' N (  32.78170)
USGS Quad:  CHARLESTON                      Longitude:  79° 55.5' W ( -79.92500)


                             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.