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Bench Mark Sheet for 8660642, NORTH MYRTLE BEACH SC

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8660642                         PUBLICATION DATE:  06/28/2004
Name:       NORTH MYRTLE BEACH                                
            SC
NOAA Chart: 11535                           Latitude:   33° 46.0' N (  33.76670)
USGS Quad:  NIXONVILLE                      Longitude:  78° 48.9' W ( -78.81500)


To reach the tidal bench marks from the intersection of U.S. Highway 17 Business
(Kings Highway) and U.S. Highway 501 (Main Street) in Myrtle Beach, proceed NW
on U.S. Highway 501 for 3.5 km (2.2 mi) to U.S. Highway 17 Bypass, then NE on
U.S. Highway 17 Bypass for 11.4 km (7.1 mi) to State Road 317, then NW on State
Road 317 for 0.24 km (0.15 mi) to the Myrtle Beach Tennis Club entrance.  The
bench marks are along a path to the Intracoastal Waterway and near the tennis
club parking lot.  The tide gage and staff were on a U.S. Army Corps of
Engineers constructed pier at the end of the path behind the tennis club pro
shop.


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


                 PRIMARY BENCH MARK STAMPING:  0642 A 1977
                         DESIGNATION:          866 0642 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3720
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1594
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 45.9' N (  33.76500)          LONGITUDE:  78° 48.9' W ( -78.81500)


The primary bench mark is a disk crimped to a copper-clad steel rod, located set
near two blazed oak trees at the edge of the Intracoastal Waterway, 80.80 m
(265.1 ft) SW of Bench Mark 0642 C 1977, 6.00 m (19.7 ft) SSE of the edge of the
waterway, 1.16 m (3.8 ft) east of the blazed 0.8-foot (0.2 m) diameter oak tree,
and 9.14 m (3.0 ft) SW of the blazed 0.40 m (1.3 ft) diameter oak tree.  The
bench mark is level with the ground, crimped to a copper-clad steel rod driven 6
m (20 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: 8660642                         PUBLICATION DATE:  06/28/2004
Name:       NORTH MYRTLE BEACH                                
            SC
NOAA Chart: 11535                           Latitude:   33° 46.0' N (  33.76670)
USGS Quad:  NIXONVILLE                      Longitude:  78° 48.9' W ( -78.81500)


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


                         BENCH MARK STAMPING:  0642 C 1977
                         DESIGNATION:          866 0642 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3721
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1593
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 46.0' N (  33.76670)          LONGITUDE:  78° 48.9' W ( -78.81500)


The bench mark is a disk crimped to a copper-clad steel rod, set near a
double-trunk oak tree at the edge of the Intracoastal Waterway, 44.68 m (146.6
ft) SW of Bench Mark 0642 D 1977, 7.25 m (23.8 ft) NE of a blazed 0.52 m (1.7
ft) diameter oak tree, 6.71 m (22.2 ft) SW of the double-trunk oak tree, and 4 m
(13 ft) SE of the edge of the waterway.  The bench mark is level with the
ground, crimped to a copper-clad steel rod driven 4 m (13 ft) to refusal, and
encased in a 4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  0642 D 1977
                         DESIGNATION:          866 0642 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3722
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1592
SETTING CLASSIFICATION:  Copper clad steel rod                 OPUS PID:        
LATITUDE:   33° 46.0' N (  33.76670)          LONGITUDE:  78° 48.9' W ( -78.81500)


The bench mark is a disk crimped to a copper-clad steel rod, set near a blazed
oak tree at the edge of the Intracoastal Waterway, 35.91 m (117.8 ft) NW of the
NW corner of the clubhouse, 16.40 m (53.8 ft) WNW of a 0.3 m (1 ft) diameter
lone cedar tree, 12.22 m (40.1 ft) NNE of a 1.7-foot (0.5 m) diameter pine tree,
and 6 m (20 ft) ENE of the blazed 0.24 m (0.8 ft) diameter oak tree.  The bench
mark is level with the ground, crimped to a copper-clad steel rod driven 4 m (13
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: 8660642                         PUBLICATION DATE:  06/28/2004
Name:       NORTH MYRTLE BEACH                                
            SC
NOAA Chart: 11535                           Latitude:   33° 46.0' N (  33.76670)
USGS Quad:  NIXONVILLE                      Longitude:  78° 48.9' W ( -78.81500)


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


                         BENCH MARK STAMPING:  0642 E 1982
                         DESIGNATION:          866 0642 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3723
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1591
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   33° 45.9' N (  33.76500)          LONGITUDE:  78° 48.7' W ( -78.81170)


The bench mark is a disk crimped to a stainless steel rod, set in a wooded area
where the pavement ends, 98 m (320 ft) SE of the pro-shop flag pole, 30.91 m
(101.4 ft) south of the south corner of a 2 m (7 ft) high chain link fence
surrounding a tennis court, 13 m (43 ft) NNE of the centerline of the paved
road, 12.98 m (42.6 ft) east of a 0.52 m (1.7 ft) diameter pine tree, and 9.30 m
(30.5 ft) west of a blazed 0.40 m (1.3 ft) diameter pine tree.  The bench mark
is level with the ground, crimped to a stainless steel rod driven 10 m (34 ft)
to refusal, and encased in a PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  0642 F 1982
                         DESIGNATION:          866 0642 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         3724
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DD1590
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   33° 45.8' N (  33.76330)          LONGITUDE:  78° 48.7' W ( -78.81170)


The bench mark is a disk crimped to a stainless steel rod, set near a row of
three pine trees in the north angle of the paved road leading to Myrtle Beach
Tennis Club, 44.81 m (147.0 ft) SW of utility pole #18, 29.99 m (98.4 ft) NW of
the centerline of the southbound lanes of the highway, 8.75 m (28.7 ft) NE of
the centerline of the paved road, and 2.01 m (6.6 ft) west of the middle tree. 
The bench mark is level with the ground, crimped to a stainless steel rod driven
14 m (46 ft) to refusal, and encased in a PVC pipe and concrete kickblock.

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

                                                                                
Station ID: 8660642                         PUBLICATION DATE:  06/28/2004
Name:       NORTH MYRTLE BEACH                                
            SC
NOAA Chart: 11535                           Latitude:   33° 46.0' N (  33.76670)
USGS Quad:  NIXONVILLE                      Longitude:  78° 48.9' W ( -78.81500)


                            T I D A L   D A T U M S 


Tidal datums at NORTH MYRTLE BEACH based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           April 1977 - July 1977
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8660854 COMBINATION BRIDGE


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.657
     MEAN HIGH WATER                            MHW    =  0.591
     MEAN TIDE LEVEL                            MTL    =  0.320
     MEAN SEA LEVEL                             MSL    =  0.302
     North American Vertical Datum              NAVD88 =  0.104
     MEAN LOW WATER                             MLW    =  0.049
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     0642 A 1977                                 8.244    7.653
     0642 C 1977                                 8.099    7.508
     0642 D 1977                                 7.793    7.202
     0642 E 1982                                 8.644    8.053
     0642 F 1982                                11.440   10.849


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

                                                                                
Station ID: 8660642                         PUBLICATION DATE:  06/28/2004
Name:       NORTH MYRTLE BEACH                                
            SC
NOAA Chart: 11535                           Latitude:   33° 46.0' N (  33.76670)
USGS Quad:  NIXONVILLE                      Longitude:  78° 48.9' W ( -78.81500)


                             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 8660642 NORTH MYRTLE BEACH, SC

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