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Bench Mark Sheet for 8728619, CAT POINT, APALACHICOLA 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


To reach the tidal bench mark from the post office in Eastpoint, proceed west on
U.S. Highway 98 for 1.93 km (1.2 mi) to State Road 65 (Bayshore Drive), then
turn left and proceed south on State Road 65 for 1.45 km (0.9 mi) to County Road
G1A (Island Drive/Bryant Patton Bridge Highway), then turn right and proceed
south on G1A to a point about 121.92 m (400.0 ft) north of a toll booth, then
turn left onto a road that runs parallel to G1A and continue south for 0.16 km
(0.1 mi) to an abandoned ferry landing.  The bench marks are located in the
vicinity of the abandoned ferry landing, toll booth, and on the bridge.  The
tide gage and staff were located at the east end of a walkway constructed across
the abandoned ferry pier.


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


                 PRIMARY BENCH MARK STAMPING:  8619 B 1977
                         DESIGNATION:          872 8619 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9848
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AS0512
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID#: AS0512
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 53.3' W ( -84.88833)


The primary bench mark is a disk located 68.58 m (225.0 ft) WSW of bench mark
8619 A 1977, 60.96 m (200.0 ft) WNW of a ramp to the old ferry landing, 16.46 m
(54.0 ft) east of a chain link fence which borders the approach to Bryant Patton
Bridge to St. George Island, 7.83 m (25.7 ft) east of the centerline of a dirt
road, and 0.09 m (0.3 ft) north of a metal witness post.  The bench mark is
crimped to the top of a copper-clad steel rod driven 12.19 m (40.0 ft) to
refusal, and encased in a 4-inch PVC pipe and concrete kick-block.  

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  8619 A 1977
                         DESIGNATION:          872 8619 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9847
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AS0513
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 53.2' W ( -84.88670)


The bench mark is a disk located NW of the abandoned ferry pier in a small grove
of trees, 26 m (85 ft) WNW of the approximate high water line on the beach,
11.67 m (38.3 ft) ESE of the SE corner of the foundation of a destroyed
building, 3.57 m (11.7 ft) SE of a two-trunked cedar tree, 2 m (7.0 ft) NNE of a
0.46 m (1.5 ft) diameter live oak tree, and 0.37 m (1.2 ft) WSW of a metal
witness post.  The bench mark is set 9 cm (0.3 ft) below ground level, 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.



                         BENCH MARK STAMPING:  8619 C 1977
                         DESIGNATION:          872 8619 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9849
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AS0510
SETTING CLASSIFICATION:  Concrete island                       OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 53.2' W ( -84.88670)


The bench mark is a disk set in the north end of the concrete island of a toll
booth for Bryant Patton Bridge to St. George Island, 4 m (13 ft) NNW of the NE
corner of the toll booth, 3 m (10 ft) west of the center of the east lane of the
toll booth, and 2.99 m (9.8 ft) east of the center of the west lane of the toll
booth.  NOTE: Mark not found in 1997 by US Power Squadron.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  8619 D 1977
                         DESIGNATION:          872 8619 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9850
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AS0509
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   29° 43.6' N (  29.72670)          LONGITUDE:  84° 53.3' W ( -84.88830)


The bench mark is a disk set in a concrete monument north of the toll booth for
Bryant Patton Bridge to St. George Island, 36 m (118 ft) NW of and across the
road from a telephone pole, 14.17 m (46.5 ft) south of power pole R-46, 12.19 m
(40.0 ft) west of the centerline of S-65, and 0.64 m (2.1 ft) east of a metal
witness post, and level with the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  C 689 2007
                         DESIGNATION:          C 689

MONUMENTATION:           Flange-encased Rod                    VM#:        19020
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   29° 44.7' N (  29.74500)          LONGITUDE:  84° 51.8' W ( -84.86333)


The bench mark is a flange encased rod located 18.90 m (62.0 ft) north of the
centerline of U.S. Highway 98, 12.50 m (41.0 ft) NE of a fire hydrant, 4.21 m
(13.8 ft) east of the centerline of 7th Street, 0.58 km (1.9 ft) SE of an
information sign (WATCH FOR CHILDREN), and 0.55 m (1.8 ft) SE of a carsonite
witness post.  The datum point is recessed 0.12 m (0.4 ft) below the level of
the NGS logo cap, being the top of a stainless steel rod in a sleeve, driven to
refusal at a depth of 17.37 m (57.0 ft) with a NGS logo cap flush with the
ground and 0.30 m (1.0 ft) below the level of the highway, and encased in a
5-inch NGS logo cap containing a magnet.      

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  B 689 2007
                         DESIGNATION:          B 689

MONUMENTATION:           Flange-encased Rod                    VM#:        19021
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   29° 44.3' N (  29.73833)          LONGITUDE:  84° 52.5' W ( -84.87500)


The bench mark is a flange-encased rod located about 146.30 m (480.0 ft) SW of
the centerline of 1st Street, about 87.48 m (287.0 ft) NE of the centerline of
the school road, 12.50 m (41.0 ft) north of the centerline of U.S. Highway 98,
3.14 m (10.3 ft) SE of the SE corner of a vacant metal building, 0.30 m (1.0 ft)
north of the north edge of a concrete sidewalk, and 0.30 m (1.0 ft) south of a
carsonite witness post.  The datum point is recessed 0.06 m (0.2 ft) below the
level of the logo cap, being the top of a stainless steel rod in a sleeve,
driven to refusal at a depth of 19.20 m (63.0 ft) flush with the ground and 0.30
m (1.0 ft) below the level of the U.S. Highway 98, and encased in a 5-inch NGS
logo cap (containing a magnet) flush with the ground.    

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  A 689 2007
                         DESIGNATION:          A 689

MONUMENTATION:           Flange-encased Rod                    VM#:        19022
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   29° 44.2' N (  29.73667)          LONGITUDE:  84° 53.3' W ( -84.88833)


The bench mark is a flange-encased rod located 12.31 m (40.4 ft) north of the
centerline of U.S. Highway 98, 5.88 m (19.3 ft) east of the centerline of
Norvell Street, 1.46 m (4.8 ft) SW of a wooden powerpole with five guy wires
attached, 1.43 m (4.7 ft) SW of a carsonite witness post, and 0.58 m (1.9 ft)
south of the south edge of a concrete sidewalk.  The datum point is recessed
0.09 m (0.3 ft) below the level of the NGS logo cap, being the top of a
stainless steel rod in a sleeve, driven to refusal at a depth of 13.11 m (43.0
ft) flush with the ground and 0.30 m (1.0 ft) below the level of the U.S.
Highway 98, and encased in a 5-inch NGS logo cap (containing a magnet) flush
with the ground.      

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


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


                         BENCH MARK STAMPING:  8619 E
                         DESIGNATION:          872 8619 E TIDAL

MONUMENTATION:           Survey disk                           VM#:        19023
AGENCY:                  Florida Dept. of Transportation (FLDOT)IDB PID#:        
SETTING CLASSIFICATION:  Concrete Guardrail                    OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 53.3' W ( -84.88833)


The bench mark is a disk set flush in the top of the guardrail above the
abutment at the NE end of the bridge, 7.04 m (23.1 ft) east of the centerline of
the highway, 6.37 m (20.9 ft) south of the end of the asphalt pavement
approaching the bridge, 1.83 m (6.0 ft) east of bench mark 8619 F, 0.85 m (2.8
ft) above the level of the State Highway 300, and 0.18 m (0.6 ft) south of the
north end of the second guardrail section south of the end of the asphalt
pavement approaching the bridge.  



                         BENCH MARK STAMPING:  8619 F
                         DESIGNATION:          872 8619 F TIDAL

MONUMENTATION:           Survey disk                           VM#:        19024
AGENCY:                  Florida Dept. of Transportation (FLDOT)IDB PID#:        
SETTING CLASSIFICATION:  Concrete Guardrail                    OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 53.3' W ( -84.88833)


The bench mark is a disk set flush in the top of the guardrail above the
abutment at the NW end of the bridge, 14.02 m (46.0 ft) west of bench mark 8619
E, 6.95 m (22.8 ft) west of the centerline of the highway, 6.40 m (21.0 ft)
south of the end of the asphalt pavement approaching the bridge, 0.85 m (2.8 ft)
above the level of the State Highway 300, and 0.18 m (0.6 ft) south of the north
end of the second guardrail section south of the end of the asphalt pavement
approaching the bridge.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


                            T I D A L   D A T U M S 


Tidal datums at CAT POINT, APALACHICOLA BAY based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           March 1984 - March 1984
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8728690 APALACHICOLA, APALACHICOLA RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.802
     MEAN HIGH WATER                            MHW    =  0.709
     North American Vertical Datum              NAVD88 =  0.511
     MEAN TIDE LEVEL                            MTL    =  0.467
     MEAN SEA LEVEL                             MSL    =  0.462
     MEAN LOW WATER                             MLW    =  0.225
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8619 B 1977                                 2.266    1.557
     8619 A 1977                                 1.550    0.841
     8619 C 1977                                 2.244    1.535
     8619 D 1977                                 1.334    0.625
     C 689 2007                                  3.185    2.476
     B 689 2007                                  2.327    1.618
     A 689 2007                                  4.590    3.881
     8619 E                                      8.117    7.408
     8619 F                                      7.273    6.564


Foot Notes:

Geodetic heights of the bench marks meet all NOAA/NOS/NGS quality control
standards for Second Order, Class 1 leveling.  It is advised that a confirmation
set of levels be established for bench marks 8619 E, 8619 F, A 689 2007, B 689
2007, and C 689 2007 to verify height differences before using tidal bench mark
elevation information.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of  9

                                                                                
Station ID: 8728619                         PUBLICATION DATE:  03/10/2011
Name:       CAT POINT, APALACHICOLA BAY                       
            FL
NOAA Chart: 11401                           Latitude:   29° 43.4' N (  29.72330)
USGS Quad:  APALACHICOLA                    Longitude:  84° 53.2' W ( -84.88670)


                             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 8728619 CAT POINT, APALACHICOLA BAY, FL

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