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Bench Mark Sheet for 8658501, ORTON POINT, CAPE FEAR RIVER NC

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8658501                         PUBLICATION DATE:  06/16/2004
Name:       ORTON POINT, CAPE FEAR RIVER                      
            NC
NOAA Chart: 11537                           Latitude:   34°  3.4' N (  34.05670)
USGS Quad:  CAROLINA BEACH                  Longitude:  77° 56.4' W ( -77.94000)


To reach the tidal bench marks from Southport, proceed by boat north on the Cape
Fear River for about 19.8 km (12.3 statue mi) to the forward range marker at the
north end of Upper Midnight Channel Range (also near the SW end of Lower Liliput
Range).  The bench marks are located on a dirt levee separating the salt marsh
from the rice fields of Orton Planatation, west and NW of the range marker.  The
tide gage and staff were located at the NW corner of the forward range marker.


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


                 PRIMARY BENCH MARK STAMPING:  8501 A 1976
                         DESIGNATION:          865 8501 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3586
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified steel rod                 OPUS PID:        
LATITUDE:   34°  3.4' N (  34.05670)          LONGITUDE:  77° 56.4' W ( -77.94000)


The primary bench mark is a disk located on the Orton Plantation levee west of
the SW end of Lower Lilput Range, in line with the NW corner of the forward
range marker and a dredging range mark adjacent to the shore.  The bench mark is
set at ground level and crimped to the top of an unspecified steel rod driven
1.2 m (4 ft).

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

                                                                                
Station ID: 8658501                         PUBLICATION DATE:  06/16/2004
Name:       ORTON POINT, CAPE FEAR RIVER                      
            NC
NOAA Chart: 11537                           Latitude:   34°  3.4' N (  34.05670)
USGS Quad:  CAROLINA BEACH                  Longitude:  77° 56.4' W ( -77.94000)


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


                         BENCH MARK STAMPING:  8501 B 1976
                         DESIGNATION:          865 8501 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3587
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified steel rod                 OPUS PID:        
LATITUDE:   34°  3.4' N (  34.05670)          LONGITUDE:  77° 56.4' W ( -77.94000)


The bench mark is a disk located on the Orton Plantation levee, 65 m (214 ft)
north of bench mark 8501 A 1976.  The bench mark is set at ground level and
crimped to the top of an unspecified steel rod driven 1.2 m (4 ft).



                         BENCH MARK STAMPING:  8501 C 1976
                         DESIGNATION:          865 8501 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3588
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified steel rod                 OPUS PID:        
LATITUDE:   34°  3.4' N (  34.05670)          LONGITUDE:  77° 56.4' W ( -77.94000)


The bench mark is a disk located on the Orton Plantation Levee, 76 m (250 ft)
north of bench mark 8501 B 1976.  The bench mark is set at ground level and
crimped to the top of an unspecified steel rod driven 1.2 m (4 ft).

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

                                                                                
Station ID: 8658501                         PUBLICATION DATE:  06/16/2004
Name:       ORTON POINT, CAPE FEAR RIVER                      
            NC
NOAA Chart: 11537                           Latitude:   34°  3.4' N (  34.05670)
USGS Quad:  CAROLINA BEACH                  Longitude:  77° 56.4' W ( -77.94000)


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


                         BENCH MARK STAMPING:  8501 D 1976
                         DESIGNATION:          865 8501 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3589
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified steel rod                 OPUS PID:        
LATITUDE:   34°  3.4' N (  34.05670)          LONGITUDE:  77° 56.4' W ( -77.94000)


The bench mark is a disk located on the Orton Plantation levee, 84 m (275 ft)
north of bench mark 8501 C 1976.  The bench mark is set at ground level and
crimped to the top of an unspecified steel rod driven 1.2 m (4 ft).



                         BENCH MARK STAMPING:  8501 E 1976
                         DESIGNATION:          865 8501 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3590
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified steel rod                 OPUS PID:        
LATITUDE:   34°  3.4' N (  34.05670)          LONGITUDE:  77° 56.4' W ( -77.94000)


The bench mark is a disk located on the Orton Plantation levee, 76 m (250 ft)
north of bench mark 8501 D 1976.  The bench mark is set at ground level and
crimped to the top of an unspecified steel rod driven 1.2 m (4 ft).

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

                                                                                
Station ID: 8658501                         PUBLICATION DATE:  06/16/2004
Name:       ORTON POINT, CAPE FEAR RIVER                      
            NC
NOAA Chart: 11537                           Latitude:   34°  3.4' N (  34.05670)
USGS Quad:  CAROLINA BEACH                  Longitude:  77° 56.4' W ( -77.94000)


                            T I D A L   D A T U M S 


Tidal datums at ORTON POINT, CAPE FEAR RIVER based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           April 1976 - June 1976
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8658120 WILMINGTON, CAPE FEAR RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.407
     MEAN HIGH WATER                            MHW    =  1.317
     MEAN SEA LEVEL                             MSL    =  0.699
     MEAN TIDE LEVEL                            MTL    =  0.682
     MEAN LOW WATER                             MLW    =  0.047
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8501 A 1976                                 2.683    1.366
     8501 B 1976                                 2.898    1.581
     8501 C 1976                                 3.099    1.782
     8501 D 1976                                 2.607    1.290
     8501 E 1976                                 2.688    1.371


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

                                                                                
Station ID: 8658501                         PUBLICATION DATE:  06/16/2004
Name:       ORTON POINT, CAPE FEAR RIVER                      
            NC
NOAA Chart: 11537                           Latitude:   34°  3.4' N (  34.05670)
USGS Quad:  CAROLINA BEACH                  Longitude:  77° 56.4' W ( -77.94000)


                             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 8658501 ORTON POINT, CAPE FEAR RIVER, NC

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