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Bench Mark Sheet for 8659898, SUNSET BEACH BRIDGE 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Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8659898                         PUBLICATION DATE:  07/26/2004
Name:       SUNSET BEACH BRIDGE                               
            NC
NOAA Chart: 11536                           Latitude:   33° 52.9' N (  33.88170)
USGS Quad:  CALABASH                        Longitude:  78° 30.6' W ( -78.51000)


To reach the tidal bench marks from the post office in Little River, proceed
north on U.S. Highway 17 for 1.9 km (1.2 mi), then turn right and proceed east
on State Highway 179 for 12.1 km (7.5 mi) through the town of Calabash and
across Calabash Creek, turn right and go south on State Highway 1172 (Sunset
Boulevard North) for 0.2 km (0.1 mi) to the bridge over Intracoastal Waterway. 
The bench marks are along State Highways 179 and 1172.  The tide gauge and staff
were located on the east side of the State Highway 1172 bridge.


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


                 PRIMARY BENCH MARK STAMPING:  S.B. NO 1 1975
                         DESIGNATION:          865 9898 S.B. TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         3647
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID#: BBCX95
LATITUDE:   33° 53.0' N (  33.88330)          LONGITUDE:  78° 34.2' W ( -78.57000)


The primary bench mark is a disk located north of the bridge on the west side of
Sunset Boulevard North, 110 m (360 ft) north of the bridge to Sunset Beach over
the Intracoastal Waterway, 13.72 m (45.0 ft) south of the SE corner of Island
Grocery, 11.89 m (39.0 ft) west of the centerline of the median of State Highway
1172, 0.85 m (2.8 ft) south of a witness post, and 0.55 m (1.8 ft) NE of the
center of a power pole.  The bench mark is set 6 cm (0.2 ft) below the ground,
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 and concrete kickblock.

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

                                                                                
Station ID: 8659898                         PUBLICATION DATE:  07/26/2004
Name:       SUNSET BEACH BRIDGE                               
            NC
NOAA Chart: 11536                           Latitude:   33° 52.9' N (  33.88170)
USGS Quad:  CALABASH                        Longitude:  78° 30.6' W ( -78.51000)


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


                         BENCH MARK STAMPING:  S.B. NO 2 1975
                         DESIGNATION:          865 9898 S.B. TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:         3648
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD4652
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 53.0' N (  33.88330)          LONGITUDE:  78° 30.7' W ( -78.51170)


The bench mark is a disk located along the south side of State Route 179, 38.77
m (127.2 ft) west of State Highway 1172, 12.89 m (42.3 ft) WNW of the NW corner
of the Island Grocery, 7.41 m (24.3 ft) south of the centerline of State Highway
179, 1.58 m (5.2 ft) NW of an unnumbered power pole, and 0.24 m (0.8 ft) north
of a steel witness post.  The bench mark is set at ground level, crimped to the
top of a copper-clad steel rod driven 14.6 m (48 ft) to refusal, and encased in
a 4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  S.B. NO 3 1975
                         DESIGNATION:          865 9898 S.B. TIDAL 3

MONUMENTATION:           Tidal Station disk                    VM#:         3649
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD4651
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 53.0' N (  33.88330)          LONGITUDE:  78° 30.8' W ( -78.51330)


The bench mark is a disk located along the south side of State Route 179, 128 m
(420 ft) west of bench mark S.B. NO 2 1975, 48 m (156 ft) west of the centerline
of a driveway belonging to Wray O. King, 16.12 m (52.9 ft) ENE of a fire
hydrant, 9.36 m (30.7 ft) south of the centerline of State Highway 179, 6.86 m
(22.5 ft) north of the westernmost triple trunk Laurel Oak tree, 1.80 m (5.9 ft)
west of an unnumbered power pole, and 1.07 m (3.5 ft) east of a steel witness
post.  The bench mark is set 6 cm (0.2 ft) below the ground, crimped to the top
of a copper-clad steel rod driven 13.4 m (44 ft) to refusal, and encased in a
4-inch PVC pipe and concrete kickblock.

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

                                                                                
Station ID: 8659898                         PUBLICATION DATE:  07/26/2004
Name:       SUNSET BEACH BRIDGE                               
            NC
NOAA Chart: 11536                           Latitude:   33° 52.9' N (  33.88170)
USGS Quad:  CALABASH                        Longitude:  78° 30.6' W ( -78.51000)


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


                         BENCH MARK STAMPING:  S.B. NO 4 1975
                         DESIGNATION:          865 9898 S.B. TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:         3650
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD4650
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 53.0' N (  33.88330)          LONGITUDE:  78° 30.8' W ( -78.51330)


The bench mark is a disk located along the south side of State Route 179, 57.52
m (188.7 ft) WSW of bench mark S.B. NO 3 1975, 41.39 m (135.8 ft) WSW of a fire
hydrant, 9.39 m (30.8 ft) south of the centerline of State Highway 179, 2.29 m
(7.5 ft) west of power pole #C-15, and 1.01 m (3.3 ft) east of a steel witness
post.  The bench mark is 3 cm (0.1 ft)  below the ground, crimped to the top of
a copper-clad steel rod driven 13.4 m (44 ft) to refusal, and encased in a
4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  S.B. NO 5 1975
                         DESIGNATION:          865 9898 S.B. TIDAL 5

MONUMENTATION:           Tidal Station disk                    VM#:         3651
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD4653
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 53.0' N (  33.88330)          LONGITUDE:  78° 30.7' W ( -78.51170)


The bench mark is a disk located along the east side of State Route 179, 101 m
(330 ft) NE of bench mark S.B. NO 2 1975, 30.94 m (101.5 ft) north of the NE
corner of ABC Store, 14.33 m (47.0 ft) west of the centerline of the median of
State Highway 179, 1.40 m (4.6 ft) south of an unnumbered power pole, and 0.24 m
(0.8 ft) west of a steel witness post.  The bench mark is set 3 cm (0.1 ft)
below the ground, crimped to the top of a copper-clad steel rod driven 13.4 m
(44 ft) to refusal, and encased in a 4-inch PVC pipe and concrete kickblock.

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

                                                                                
Station ID: 8659898                         PUBLICATION DATE:  07/26/2004
Name:       SUNSET BEACH BRIDGE                               
            NC
NOAA Chart: 11536                           Latitude:   33° 52.9' N (  33.88170)
USGS Quad:  CALABASH                        Longitude:  78° 30.6' W ( -78.51000)


                            T I D A L   D A T U M S 


Tidal datums at SUNSET BEACH BRIDGE based on:

     LENGTH OF SERIES:      6 MONTHS
     TIME PERIOD:           December 1974 - May 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   =  1.608
     MEAN HIGH WATER                            MHW    =  1.489
     MEAN SEA LEVEL                             MSL    =  0.785
     MEAN TIDE LEVEL                            MTL    =  0.769
     MEAN LOW WATER                             MLW    =  0.050
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     S.B. NO 1 1975                              5.089    3.600
     S.B. NO 2 1975                              5.319    3.830
     S.B. NO 3 1975                              6.767    5.278
     S.B. NO 4 1975                              6.974    5.485
     S.B. NO 5 1975                              3.837    2.348


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

                                                                                
Station ID: 8659898                         PUBLICATION DATE:  07/26/2004
Name:       SUNSET BEACH BRIDGE                               
            NC
NOAA Chart: 11536                           Latitude:   33° 52.9' N (  33.88170)
USGS Quad:  CALABASH                        Longitude:  78° 30.6' W ( -78.51000)


                             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 8659898 SUNSET BEACH BRIDGE, NC

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