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Bench Mark Sheet for 8728229, SHELL POINT, WALKER CREEK FL

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


To reach the tidal bench marks from the intersection of U.S. Highway 98 and its
Y intersection with State Highway 367, proceed south on State Highway 367 for 3
km (2 mi) to its Y intersection with State Highway 367A, continue on State
Highway 367 for 5.6 km (3.5 mi) to Shell Point.  The bench marks are on the boat
ramp and along the bulkhead behind the Shell Point Resort Marina.  The tide gage
and staff are located at the NE corner of the pier next to the floating dock.


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


                 PRIMARY BENCH MARK STAMPING:  NO 1 1973
                         DESIGNATION:          872 8229 TIDAL 1

MONUMENTATION:           Survey disk                           VM#:         8298
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BE1802
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.5' W ( -84.29170)


The primary bench mark is a disk set flush in a concrete bulkhead of the boat
launching ramp at Shell Point Marina, 8.53 m (28.0 ft) west of the west bulkhead
of the sailboat canal and directly in front of the tide house, 1.92 m (6.3 ft)
south of the north end of the east wall, and 0.18 m (0.6 ft) east of the west
edge of the wall.

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

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


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


                         BENCH MARK STAMPING:  SHELL POINT II 1933
                         DESIGNATION:          SHELL POINT 2

MONUMENTATION:           Triangulation Station disk            VM#:         8296
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BE1938
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   30°  3.5' N (  30.05830)          LONGITUDE:  84° 17.3' W ( -84.28830)


The bench mark is a disk set flush in a concrete monument 33.53 m (110.0 ft)
north of the shoreline of Apalachee Bay, 21.64 m (71.0 ft) east of a 0.46 m (1.5
ft) diameter cedar tree, 18 m (58 ft) south of the centerline of a main paved
road, 11 m (37 ft) SW of a 0.76 m (2.5 ft) diameter cedar tree located on an
island in the paved road, 0.24 m (0.8 ft) north of a witness post with a sign,
and 0.15 m (0.5 ft) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


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


                         BENCH MARK STAMPING:  SHELL POINT II 1933 NO 3 1972
                         DESIGNATION:          SHELL POINT 2 RM 3

MONUMENTATION:           Azimuth Mark disk                     VM#:         8297
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BE1939
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   30°  3.5' N (  30.05830)          LONGITUDE:  84° 17.3' W ( -84.28830)


The bench mark is a disk set flush in a concrete monument, 32.31 m (106.0 ft) SE
of Bench Mark Shell Point II 1933, 28.35 m (93.0 ft) SE of a 0.46 m (1.5 ft)
diameter cedar tree, 13.41 m (44.0 ft) north of the shoreline of Apalachee Bay,
0.15 m (0.5 ft) north of a witness post, and 0.61 m (2.0 ft) above ground level
due to beach erosion.



                         BENCH MARK STAMPING:  NO 2 1973
                         DESIGNATION:          872 8229 TIDAL 2

MONUMENTATION:           Survey disk                           VM#:         8299
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BE1801
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.5' W ( -84.29170)


The bench mark is a disk set flush in a concrete bulkhead of the boat launching
ramp at the Shell Point Marina, 26.91 m (88.3 ft) south of Bench Mark NO 1 1973,
17.28 m (56.7 ft) NW of a transformer and utility pole #TEC-A3-131, 2.04 m (6.7
ft) north of the south end of the east wall, and 0.18 m (0.6 ft) east of the
west edge of the wall.

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

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


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


                         BENCH MARK STAMPING:  NO 3 1973
                         DESIGNATION:          872 8229 TIDAL 3

MONUMENTATION:           Survey disk                           VM#:         8300
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BE1800
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.5' W ( -84.29170)


The bench mark is a disk set flush in a concrete bulkhead of the boat launching
ramp, 9.69 m (31.8 ft) west of Bench Mark NO 2 1973, 1.77 m (5.8 ft) north of
the south end of the concrete bulkhead, and 0.18 m (0.6 ft) east of the west
edge of the west wall.



                         BENCH MARK STAMPING:  NO 4 1973
                         DESIGNATION:          872 8229 TIDAL 4

MONUMENTATION:           Survey disk                           VM#:         8301
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BE1799
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.5' W ( -84.29170)


The bench mark is a disk set flush in a 1 m x 1 m (3 ft x 3 ft) concrete
foundation, 7.71 m (25.3 ft) west of the NW corner of the west wall of a
launching ramp, 3.23 m (10.6 ft) east of the west bulkhead west of the ramp, and
2.96 m (9.7 ft) south of the north bulkhead on the west side of the boat ramp.

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

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


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


                         BENCH MARK STAMPING:  NO 5 1973
                         DESIGNATION:          872 8229 TIDAL 5

MONUMENTATION:           Survey disk                           VM#:         8302
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BE1798
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.5' W ( -84.29170)


The bench mark is a disk set flush in a concrete seawall on the west bulkhead,
west of the launching ramp of the Shell Point Marina, 23.90 m (78.4 ft) south of
the north end of the west bulkhead, 5.18 m (17.0 ft) north of the north end of
the fuel dock, and 0.18 m (0.6 ft) east of the west edge of the bulkhead.



                         BENCH MARK STAMPING:  FLORIDA D.N.R. U
                         DESIGNATION:          872 8229 D.N.R. U

MONUMENTATION:           Survey disk                           VM#:         8303
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   30°  3.6' N (  30.06000)          LONGITUDE:  84° 17.4' W ( -84.29000)


The bench mark is a disk set flush in the top of a concrete monument, encased in
a 4-inch PVC pipe, located at the south end (dead end) of State Highway 367,
58.22 m (191.0 ft) SW of the south corner of the NW wing of the Shell Point
Motel, 48.77 m (160.0 ft) east of the NE corner of a single story concrete block
residence, 32.61 m (107.0 ft) south of the centerline of a dead end dirt road
leading west from State Highway 367, 23.47 m (77.0 ft) north of the shoreline of
Apalachee Bay, 7.62 m (25.0 ft) east of the centerline of the west fork of State
Highway 367, 0.30 m (1.0 ft) east of a survey marker witness sign, and 0.15 m
(0.5 ft) above ground level.

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

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


                            T I D A L   D A T U M S 


Tidal datums at SHELL POINT based on:

     LENGTH OF SERIES:      12 Years
     TIME PERIOD:           1/1974 - 12/1981 ; 1/1983 - 12/1986
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8727520 CEDAR KEY, GULF OF MEXICO


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

     HIGHEST OBSERVED WATER LEVEL (11/21/1985)         =  2.978
     MEAN HIGHER HIGH WATER                     MHHW   =  1.085
     MEAN HIGH WATER                            MHW    =  1.012
     MEAN TIDE LEVEL                            MTL    =  0.609
     MEAN SEA LEVEL                             MSL    =  0.595
     North American Vertical Datum              NAVD88 =  0.589
     MEAN LOW WATER                             MLW    =  0.205
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/17/1981)         = -1.134

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 1 1973                                   2.338    1.326
     SHELL POINT II 1933                         2.695    1.683
     SHELL POINT II 1933 NO 3 1972               2.096    1.084
     NO 2 1973                                   2.391    1.379
     NO 3 1973                                   2.440    1.428
     NO 4 1973                                   2.032    1.020
     NO 5 1973                                   1.552    0.540
     FLORIDA D.N.R. U                            2.149    1.137


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

                                                                                
Station ID: 8728229                         PUBLICATION DATE:  04/21/2003
Name:       SHELL POINT                                       
            FL
NOAA Chart:                                 Latitude:   30°  3.6' N (  30.06000)
USGS Quad:                                  Longitude:  84° 17.4' W ( -84.29000)


                             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 8728229 SHELL POINT, WALKER CREEK, FL

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