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Bench Mark Sheet for 8724964, COON KEY PASS, GULLIVAN BAY 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8724964                         PUBLICATION DATE:  09/27/2010
Name:       COON KEY PASS, GULLIVAN BAY                       
            FL
NOAA Chart: 11429                           Latitude:   25° 53.8' N (  25.89670)
USGS Quad:  MARCO ISLAND                    Longitude:  81° 38.2' W ( -81.63670)


To reach the tidal bench marks from Goodland, proceed by boat SE through Cook
Key Pass for 2.6 km (1.8 nm) to the SW end of Tripod Key.  The bench marks are
located on the highest ridge on the SW end of Tripod Key.  The tide gage and
staff were located on a small offshore platform, about 18 m (60 ft) SW of the SW
end of Tripod Key.


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


                 PRIMARY BENCH MARK STAMPING:  4964 A 1978
                         DESIGNATION:          872 4964 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9725
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   25° 53.8' N (  25.89670)          LONGITUDE:  81° 38.2' W ( -81.63670)


The primary bench mark is a disk located on the shoreline, 56 m (184 ft) WNW of
bench mark 4964 C 1978, 0.34 m (1.1 ft) south of a new witness sign and 0.15 m
(0.5 ft) south of an old witness sign.  The bench mark is 0.55 m (1.8 ft) above
ground level, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft)
to refusal, and encased in 6-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: 8724964                         PUBLICATION DATE:  09/27/2010
Name:       COON KEY PASS, GULLIVAN BAY                       
            FL
NOAA Chart: 11429                           Latitude:   25° 53.8' N (  25.89670)
USGS Quad:  MARCO ISLAND                    Longitude:  81° 38.2' W ( -81.63670)


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


                         BENCH MARK STAMPING:  4964 B 1978
                         DESIGNATION:          872 4964 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9726
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   25° 53.8' N (  25.89670)          LONGITUDE:  81° 38.2' W ( -81.63670)


The bench mark is a disk located 34 m (111 ft) ESE of bench mark 4964 A 1978, 6
m (19 ft) ESE of the approximate high water line, 0.30 m (1 ft) SW of a new
witness post, and 0.15 m (0.5 ft) SW of an old witness sign.  The bench mark is
3 cm (0.1 ft) above the pipe, crimped to the top of a galvanized steel rod
driven 9.8 m (32 ft) to refusal, and encased in a 4-inch steel pipe and concrete
kickblock.



                         BENCH MARK STAMPING:  4964 C 1978
                         DESIGNATION:          872 4964 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9727
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   25° 53.8' N (  25.89670)          LONGITUDE:  81° 38.2' W ( -81.63670)


The bench mark is a disk located 22 m (73 ft) SE of bench mark 4964 B 1978, 20 m
(66 ft) ESE of the approximate high water line, 0.37 m (1.2 ft) SW of a new
witness post, and 0.15 m (0.5 ft) SW of an old witness sign. The bench mark is 3
cm (0.1 ft) above the pipe, crimped to the top of a galvanized steel rod driven
9.8 m (32 ft) to refusal, and encased in a 4-inch steel pipe and concrete
kickblock.

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

                                                                                
Station ID: 8724964                         PUBLICATION DATE:  09/27/2010
Name:       COON KEY PASS, GULLIVAN BAY                       
            FL
NOAA Chart: 11429                           Latitude:   25° 53.8' N (  25.89670)
USGS Quad:  MARCO ISLAND                    Longitude:  81° 38.2' W ( -81.63670)


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


                         BENCH MARK STAMPING:  4964 D 1978
                         DESIGNATION:          872 4964 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9728
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   25° 53.8' N (  25.89670)          LONGITUDE:  81° 38.2' W ( -81.63670)


The bench mark is a disk located 17.07 m (56.0 ft) ESE of the approximate high
water line, 8.05 m (26.4 ft) south of bench mark 4964 C 1978, 3 m (10 ft) NE of
the approximate shoreline, 0.34 m (1.1 ft) SW of the new witness post, and 0.15
m (0.5 ft) SW of the old witness post.  The bench mark is 0.21 m (0.7 ft) above
ground level, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft)
to refusal, and encased in a 4-inch steel pipe and concrete kickblock.



                         BENCH MARK STAMPING:  4964 F 1984
                         DESIGNATION:          872 4964 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9729
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   25° 53.8' N (  25.89670)          LONGITUDE:  81° 38.2' W ( -81.63670)


The bench mark is a disk located 16.61 m (54.5 ft) NW of bench mark 4964 B 1978,
15.97 m (52.4 ft) ENE of bench mark 4964 A 1978, 9 m (30 ft) NE of the
approximate shoreline, and 0.46 m (1.5 ft) SW of a witness post.  The bench mark
is level with the ground, crimped to the top of a stainless steel rod driven 8.5
m (28 ft) to refusal, and encased in a 6-inch PVC pipe.

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

                                                                                
Station ID: 8724964                         PUBLICATION DATE:  09/27/2010
Name:       COON KEY PASS, GULLIVAN BAY                       
            FL
NOAA Chart: 11429                           Latitude:   25° 53.8' N (  25.89670)
USGS Quad:  MARCO ISLAND                    Longitude:  81° 38.2' W ( -81.63670)


                            T I D A L   D A T U M S 


Tidal datums at COON KEY PASS, GULLIVAN BAY based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           March 1978 and May 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8724967 MARCO ISLAND, CAXAMBAS PASS


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.156
     MEAN HIGH WATER                            MHW    =  1.073
     MEAN TIDE LEVEL                            MTL    =  0.631
     MEAN SEA LEVEL                             MSL    =  0.627
     MEAN LOW WATER                             MLW    =  0.189
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4964 A 1978                                 1.670    0.597
     4964 B 1978                                 1.705    0.632
     4964 C 1978                                 2.476    1.403
     4964 D 1978                                 2.414    1.341
     4964 F 1984                                 1.634    0.561


Foot Notes:

Bench mark 4964 F 1984 is based 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 this mark.

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

                                                                                
Station ID: 8724964                         PUBLICATION DATE:  09/27/2010
Name:       COON KEY PASS, GULLIVAN BAY                       
            FL
NOAA Chart: 11429                           Latitude:   25° 53.8' N (  25.89670)
USGS Quad:  MARCO ISLAND                    Longitude:  81° 38.2' W ( -81.63670)


                             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 8724964 COON KEY PASS, GULLIVAN BAY, FL

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