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Bench Mark Sheet for 8658120, Wilmington 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


To reach the tidal bench marks from the draw bridge over the Cape Fear River
Highway 17 South, take the first exit pass bridge to the U.S. North Carolina
Battleship Memorial and Battleship Drive.  Turn right on road across from the
Battleship and proceed 1.9 km (1.2 mi) to the main entrance of the U.S. Corp of
Engineers, Eagle Island maintenance yard and docks.  The bench marks are in the
general vicinity of the yard.  The tide station is located in the NE corner of
the dock.


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


                 PRIMARY BENCH MARK STAMPING:  8120 D 1976
                         DESIGNATION:          865 8120 D

MONUMENTATION:           Tidal Station disk                    VM#:          554
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   34° 13.3' N (  34.22170)          LONGITUDE:  77° 57.2' W ( -77.95330)


The primary bench mark is a disk located at the U.S. Army Corps of Engineers
Eagle Island Maintenance Yard, 11.58 m (38.0 ft) south of the north face of the
sheet pile bulkhead, 9.75 m (32.0 ft) east of the center of a concrete boat
ramp, and 0.61 m (2.0 ft) north of the northern side of a concrete foundation
(for the old welding shop).  The bench mark is at ground level, crimped to the
top of a copper-clad steel rod driven to an unspecified depth, encased in a
5-inch PVC pipe and concrete kickblock which projects 0.15 m (0.5 ft) above the
ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


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


                         BENCH MARK STAMPING:  8120 C 1976
                         DESIGNATION:          865 8120 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          556
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  EA3077
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   34° 13.6' N (  34.22670)          LONGITUDE:  77° 57.2' W ( -77.95330)


The bench mark is a disk located at the U.S. Corps of Engineers (COE) Eagle
Island Maintenance Yard, on the SW side of the COE property line, 23.47 m (77.0
ft) SE of the SE corner of the shop and office building, 8.35 m (27.4 ft) SW of
the SW corner of the building, and 0.70 m (2.3 ft) NE of the SW fence line and
behind the electrical shop. The bench mark is crimped to the top of a
copper-clad steel rod driven to an unspecified depth, encased in a 5-inch PVC
pipe and concrete kickblock.



                         BENCH MARK STAMPING:  8120 E 1982
                         DESIGNATION:          865 8120 E

MONUMENTATION:           Tidal Station disk                    VM#:          557
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   34° 13.7' N (  34.22830)          LONGITUDE:  77° 57.3' W ( -77.95500)


The bench mark is a disk located near the SW corner of the U.S. Corps of
Engineers (COE) Eagle Island Maintenance Yard, 39.32 m (129.0 ft) SSW of the
centerline of the road leading into the yard, 8.53 m (28.0 ft) east of the
centerline of State Road 1300, 2.01 m (6.6 ft) NE of the NW corner of the fence
around the Gregory-Poole Equipment Yard, and 0.91 m (3.0 ft) NW of the SW corner
of the fence around the yard.  The bench mark is crimped to the top of a
galvanized steel rod driven 12.5 m (41 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  3 of  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


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


                         BENCH MARK STAMPING:  8120 G 1989
                         DESIGNATION:          865 8120 G

MONUMENTATION:           Tidal Station disk                    VM#:          560
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   34° 13.6' N (  34.22670)          LONGITUDE:  77° 57.3' W ( -77.95500)


The bench mark is a disk located at the U.S. Army Corps of Engineers (COE) Eagle
Island MaintenanceYard, 31.21 M (102.4 FT) north of the centerline of the COE
entrance road,11.52 m (37.8 ft) SSW of the centerline of the drive entrance to
the COE parking lot, 8.41 m (27.6 ft) east of the centerline of State Road 1300,
and 0.79 m (2.6 ft) west of a chainlink fence.  The bench mark is 12 cm (0.4 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 5-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  8120 J 1989
                         DESIGNATION:          865 8120 J

MONUMENTATION:           Tidal Station disk                    VM#:          562
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete bridge support               OPUS PID:        
LATITUDE:   34° 13.7' N (  34.22830)          LONGITUDE:  77° 57.3' W ( -77.95500)


The bench mark is a disk set vertically in the SW of two concrete supports of
the third bent east of the west end of the U.S. Highway 17 bridge over the Cape
Fear River, 94.49 m (310.0 ft) west of State Road 1300, 51.82 m (170.0 ft) east
of the base of the concrete headwall for the bridge abutement, and 1.52 m (5.0
ft) above the ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


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


                         BENCH MARK STAMPING:  5 1937
                         DESIGNATION:          865 8120 TIDAL 5 USE

MONUMENTATION:           Tidal Station disk                    VM#:        16965
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  EA0555
SETTING CLASSIFICATION:  Concrete doorsill                     OPUS PID:        
LATITUDE:   34° 13.6' N (  34.22670)          LONGITUDE:  77° 57.2' W ( -77.95330)


The bench mark is a disk set inside of a 4-inch pipe in the top of the concrete
doorsill of the north entrance to the storage warehouse, 4.67 m (15.3 ft) east
of the east face of the office and warehouse building, 0.15 m (0.5 ft) west of
teh east end of the doorsill, and about level with the sidewalk.   NOTE: The
bench mark cannot be leveled with standard barcode rods. (Use steel ruler or
short rod instead.)



                         BENCH MARK STAMPING:  8120 N 2014
                         DESIGNATION:          865 8120 N

MONUMENTATION:           Tidal Station disk                    VM#:        21248
AGENCY:                  US Army Corps of Engineers            IDB PID:         
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID:        
LATITUDE:   34° 13.6' N (  34.22736)          LONGITUDE:  77° 57.2' W ( -77.95361)


The bench mark is a disk set flush in a concrete pad at the E end of the Corps
Of Engineers Maint. Yard property near the NOAA Tide Station, 40.51 m (132.9 ft)
ENE of the NE corner of the welding shop, 6.86 m (22.5 ft) W of the E edge of
the waterfront concrete pad leading to the bulkhead, 0.22 m (0.7 ft) E of the W
edge of a concrete pad next to the tide station building.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


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


                         BENCH MARK STAMPING:  8120 P 2014
                         DESIGNATION:          865 8120 P

MONUMENTATION:           Tidal Station disk                    VM#:        21249
AGENCY:                  US Army Corps of Engineers            IDB PID:         
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID:        
LATITUDE:   34° 13.6' N (  34.22728)          LONGITUDE:  77° 57.2' W ( -77.95364)


The mark is a disk 0.25 m (0.8 ft) E of the W edge of the SW corner set flush in
a concrete pad at the E end of the Corps Of Engineers Maint. Yard property near
the NOAA Tide Station, 35.47 m (116.37 ft) E of the NE corner of the welding
shop, 21.97 m (72.08 ft) S of the SE corner of the NOAA Tide Station house, 6.95
m (22.8 ft) W of E the waterfront concrete pad, 1.73 m (5.7 ft) WSW of SW corner
of concrete pad.



                         BENCH MARK STAMPING:  8120 R 2015
                         DESIGNATION:          865 8720 R

MONUMENTATION:           Tidal Station disk                    VM#:        21808
AGENCY:                  NOS                                   IDB PID:         
SETTING CLASSIFICATION:  Set in a bridge support column        OPUS PID:        
LATITUDE:   34° 13.7' N (  34.22870)          LONGITUDE:  77° 57.3' W ( -77.95522)


The mark is vertically set in the second north support column of the Cape Fear
Memorial Bridge, 31.10 m (102.0 ft) W of centerline of Battleship Rd NE, 26.20 m
(86.0 ft) S of large column holding a billboard, 10.25 m (33.6 ft) E of adjacent
support column in second row, 1.35 m (4.4 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


                            T I D A L   D A T U M S 


Tidal datums at WILMINGTON, CAPE FEAR RIVER 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 (10/08/2016)         =  2.489
     MEAN HIGHER HIGH WATER                     MHHW   =  1.427
     MEAN HIGH WATER                            MHW    =  1.351
     North American Vertical Datum              NAVD88 =  0.792
     MEAN SEA LEVEL                             MSL    =  0.743
     MEAN TIDE LEVEL                            MTL    =  0.699
     MEAN LOW WATER                             MLW    =  0.047
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (02/12/1981)         = -0.567

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8120 D 1976                                 1.707    0.356
     8120 C 1976                                 1.912    0.561
     8120 E 1982                                 1.846    0.495
     8120 G 1989                                 1.655    0.304
     8120 J 1989                                 3.239    1.888
     5 1937                                      1.655    0.304
     8120 N 2014                                 2.306    0.955
     8120 P 2014                                 2.226    0.875
     8120 R 2015                                 3.440    2.089


Foot Notes:

Bench mark 8120 R 2015 is issed on one differential leveling connection and does
not meet the quality control standards of the NOS. Therefore, caution should be
used when deriving elevations for these marks.

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

                                                                                
Station ID: 8658120                         PUBLICATION DATE:  10/06/2017
Name:       WILMINGTON, CAPE FEAR RIVER                       
            NC
NOAA Chart: 11537                           Latitude:   34° 13.6' N (  34.22750)
USGS Quad:  WILMINGTON                      Longitude:  77° 57.2' W ( -77.95361)


                             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 8658120 Wilmington, NC

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services