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Bench Mark Sheet for 8726533, JOHNS PASS 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


To reach the tidal bench marks from the intersection of Gulf Boulevard (County
Road 699) and Madeira Beach Causeway (Tom Stuart Causeway), proceed south on
Gulf Boulevard for 2.6 km (1.6 mi) to 129th Avenue West, then turn left and
proceed NE on 129th Avenue West for 0.2 km (0.1 mi) to Gulf Boulevard East, then
turn right onto Gulf Boulevard East and proceed SE to the waters edge.  The
bench marks are near the drawbridge and at the end of Gulf Boulevard East.  The
tide gage and staff were located on the west side of the western dock belonging
to Atlantis Boat Docks.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


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


                 PRIMARY BENCH MARK STAMPING:   
                         DESIGNATION:          BRIDGE FLDT
                         ALIAS:                SRD (NORTH)

MONUMENTATION:           Bench Mark disk                       VM#:         6546
AGENCY:                  Florida State Road Department (FLSRD) IDB PID#:  AG7412
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   27° 47.1' N (  27.78500)          LONGITUDE:  82° 47.0' W ( -82.78330)


The primary bench mark is a disk set in the top of a 1.07 m (3.5 ft) high
concrete wall between the southbound and northbound lanes of Gulf Boulevard at
the north end of the bridge over Johns Pass, and 1 m (4 ft) above the level of
the highway.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


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


                         BENCH MARK STAMPING:  BM NO 5 1951
                         DESIGNATION:          872 6533 TIDAL 5
                         ALIAS:                TIDAL STA 3 51

MONUMENTATION:           Tidal Station disk                    VM#:         6542
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG5439
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   27° 47.1' N (  27.78500)          LONGITUDE:  82° 46.9' W ( -82.78170)


The bench mark is a disk set in the top of a concrete monument near the north
end of the former Johns Pass bridge, 18 m (60 ft) south of 128th Avenue East, 9
m (30 ft) west of Gulf Boulevard East, 0.46 m (1.5 ft) west of the west curb of
the former Johns Pass bridge, and 0.15 m (0.5 ft) above the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


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


                         BENCH MARK STAMPING:  RAINEY 1973
                         DESIGNATION:          RAINEY

MONUMENTATION:           Survey disk                           VM#:         6543
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG5449
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   27° 47.0' N (  27.78330)          LONGITUDE:  82° 47.0' W ( -82.78330)


The bench mark is a disk set in a concrete sidewalk on the Johns Pass
drawbridge, 5.33 m (17.5 ft) west of the centerline of the southbound lane of
Gulf Boulevard, and 2 m (8 ft) north of a metal light pole.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


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


                         BENCH MARK STAMPING:  RAINEY NO 1 1973
                         DESIGNATION:          RAINEY RM 1

MONUMENTATION:           Reference Mark disk                   VM#:         6544
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG0826
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   27° 46.9' N (  27.78170)          LONGITUDE:  82° 46.9' W ( -82.78170)


The bench mark is a disk set in a concrete sidewalk on the Johns Pass
drawbridge, on the east side of the southbound highway, 5.33 m (17.5 ft) east of
the centerline of the southbound lane of Gulf Boulevard, and 0.76 m (2.5 ft)
east of the west edge of the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


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


                         BENCH MARK STAMPING:  RAINEY NO 2 1973
                         DESIGNATION:          RAINEY RM 2

MONUMENTATION:           Reference Mark disk                   VM#:         6545
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG0825
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   27° 46.9' N (  27.78170)          LONGITUDE:  82° 46.9' W ( -82.78170)


The bench mark is a disk set in a concrete sidewalk on the Johns Pass
drawbridge, on the west side of the southbound highway, 5.33 m (17.5 ft) west of
the centerline of the southbound lane of Gulf Boulevard, and 1 m (2 ft) east of
the west wall of the bridge.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  8

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


                            T I D A L   D A T U M S 


Tidal datums at JOHNS PASS based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           June 1976 - July 1976
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8726724 CLEARWATER BEACH, GULF OF MEXICO


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.684
     MEAN HIGH WATER                            MHW    =  0.576
     North American Vertical Datum              NAVD88 =  0.436
     MEAN TIDE LEVEL                            MTL    =  0.356
     MEAN SEA LEVEL                             MSL    =  0.353
     MEAN LOW WATER                             MLW    =  0.136
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     BRIDGE FLDT                                 6.160    5.584
     BM NO 5 1951                                2.409    1.833
     RAINEY 1973                                 9.578    9.002
     RAINEY NO 1 1973                            9.613    9.037
     RAINEY NO 2 1973                            9.255    8.679


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

                                                                                
Station ID: 8726533                         PUBLICATION DATE:  02/05/2004
Name:       JOHNS PASS                                        
            FL
NOAA Chart: 11412                           Latitude:   27° 47.1' N (  27.78500)
USGS Quad:  SEMINOLE                        Longitude:  82° 46.9' W ( -82.78170)


                             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 8726533 JOHNS PASS, FL

Revised: 08/08/2018
NOAA / National Ocean Service
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