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Bench Mark Sheet for 8722429, HOBE SOUND BRIDGE, HOBE SOUND

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


To reach the tidal bench marks from the intersection of U.S. Highway 1 and State
Road 708, proceed 1.45 km (0.9 mi) east on State Road 708 to the Hobe Sound
Bridge over the Intracoastal Waterway.  The bench marks are located on the
bridge and adjacent to State Road 708 east of the bridge.  The tide gage and
staff were located on the north end of the west fender of the Hobe Sound Bridge.


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


                 PRIMARY BENCH MARK STAMPING:  2429 A 1980
                         DESIGNATION:          872 2429 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5481
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AF6979
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   27°  3.9' N (  27.06500)          LONGITUDE:  80°  7.2' W ( -80.12000)


The primary bench mark is a disk located 7.44 m (24.4 ft) NNW of State Road 707
centerline, 1.43 m (4.7 ft) NNW of a Drawbridge Ahead sign, 2.35 m (7.7 ft) SSE
of the edge of a bike path, 8.87 m (29.1 ft) WSW of a ficus tree, 7.92 m (26.0
ft) ENE of another ficus tree, and 0.85 m (2.8 ft) SSE of a witness post.



                         BENCH MARK STAMPING:  2429 B 1980
                         DESIGNATION:          872 2429 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5482
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AF6980
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   27°  3.9' N (  27.06500)          LONGITUDE:  80°  7.1' W ( -80.11833)


The bench mark is a disk located 8.84 m (29.0 ft) WSW of a ficus tree, 7.77 m
(25.5 ft) ENE of another ficus tree, 5.88 m (19.3 ft) SSE of State Road 707
centerline, and 0.43 m 0.43 m (1.4 ft) NNW of a witness post.

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


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


                         BENCH MARK STAMPING:  2429 C 1980
                         DESIGNATION:          872 2429 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5483
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AF6981
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   27°  4.0' N (  27.06670)          LONGITUDE:  80°  7.1' W ( -80.11833)


The bench mark is a disk located 14.48 m (47.5 ft) NNE of the junction of Gomez
Road with State Road 707, 6.83 m (22.4 ft) NNW of State Road 707 centerline,
2.23 m (7.3 ft) SSE of the south edge of a bike path, and 1.07 m (3.5 ft) NNE of
the junction of Gomez Road with State Road 707.



                         BENCH MARK STAMPING:  2429 D 1980
                         DESIGNATION:          872 2429 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5484
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AF6983
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   27°  4.0' N (  27.06670)          LONGITUDE:  80°  7.0' W ( -80.11667)


The bench mark is a disk located 34.14 m (112.0 ft) west of a sea wall, 3.41 m
(11.2 ft) north of the north edge of the park parking lot, 0.43 m (1.4 ft) south
of a 5-foot high concrete block wall painted white, and 0.27 m (0.9 ft) south of
a witness post.

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


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


                         BENCH MARK STAMPING:  H 309 1970
                         DESIGNATION:          H 309

MONUMENTATION:           Bench Mark disk                       VM#:         5488
AGENCY:                  US Coastal and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AF3022
SETTING CLASSIFICATION:  Copper-Clad Steel Rod                 OPUS PID:        
LATITUDE:   27°  4.0' N (  27.06670)          LONGITUDE:  80°  7.0' W ( -80.11670)


The bench mark is a disk located 12.19 m (40.0 ft) NE of the center of the
intersection of Highway 707 and a paved drive leading north, near the entrance
to a parking area for the beach 10.06 m (33.0 ft) east of the center line of the
paved road, 7.62 m (25.0 ft) north of the center line of a driveway through the
parking area, 4.27 m (14.0 ft) west of the center line of a NS driveway, 0.61 m
(2.0 ft) north of a power pole, 0.15 m (0.5 ft) west of a metal witness post,
and about level with the road.  The bench mark is set on the top of a 5/8-inch
copper coated rod that projects 1-inch driven to refusal at a depth of 6.71 m
(22.0 ft) and is encased in a 4-inch metal witness pipe which projects 3-inches
above the surface of the ground.on the top   

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


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


                         BENCH MARK STAMPING:  M 308 1970
                         DESIGNATION:          M 308

MONUMENTATION:           Bench Mark disk                       VM#:        18925
AGENCY:                  US Coastal and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AF3020
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   24°  2.7' N (  24.04500)          LONGITUDE:  80°  6.4' W ( -80.10667)


The bench mark is a disk set in the top of a concrete post projecting 0.61 m
(2.0 in) above the level of the ground, 13.11 m (43.0 ft) SW of the center of
the junction of Highway A1A and Devonshire Lane, 12.19 m (40.0 ft) west of the
center line of Highway A1A, 4.27 m (14.0 ft) south of the center line of
Devonshire Lane, 0.79 m (2.6 ft) east of the NE corner of a high fence around a
private tennis court, in line with a 6 foot high concrete east-west fence line,
and 0.18 m (0.6 ft) west of a metal witness post.  The bench mark is 0.30 m (1.0
ft) below the level of the highway, about level with the street.  

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


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


                         BENCH MARK STAMPING:  L 308 1970
                         DESIGNATION:          L 308

MONUMENTATION:           Bench Mark disk                       VM#:        18926
AGENCY:                  US Coastal and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AF3021
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   27°  3.3' N (  27.05500)          LONGITUDE:  80°  6.7' W ( -80.11167)


The benchmark is a disk set in the top of a concrete post projecting 1-inch
above the level of the ground, 25.60 m (84.0 ft) SE of the SE edge of the green
at the 7th hole of a golf course, 4.88 m (16.0 ft) west of the center line of
State Highway A1A, 3.05 m (10.0 ft) south of the extended centerline of a
driveway leading east, 0.76 m (2.5 ft) south of a 10-inch palm tree, 0.21 m (0.7
ft) west of a metal witness post.  The bench mark is 0.30 m (1.0 ft) above the
level of the highway.  

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


                            T I D A L   D A T U M S 


Tidal datums at HOBE SOUND BRIDGE, HOBE SOUND based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           August 1969 - July 1970
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8723170 MIAMI BEACH (CITY PIER)


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

     HIGHEST OBSERVED WATER LEVEL (10/31/1969)         =  1.042
     North American Vertical Datum              NAVD88 =  0.645
     MEAN HIGHER HIGH WATER                     MHHW   =  0.534
     MEAN HIGH WATER                            MHW    =  0.497
     MEAN SEA LEVEL                             MSL    =  0.271
     MEAN TIDE LEVEL                            MTL    =  0.269
     MEAN LOW WATER                             MLW    =  0.040
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (04/24/1970)         = -0.336

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     2429 A 1980                                 1.751    1.254
     2429 B 1980                                 1.883    1.386
     2429 C 1980                                 2.698    2.201
     2429 D 1980                                 4.905    4.408
     H 309 1970                                  4.004    3.507
     M 308 1970                                  4.667    4.170
     L 308 1970                                  4.844    4.347


Foot Notes:

Bench marks M 308 1970 and L 308 1970 are based on one differential leveling
connection and do not meet the quality control standards of the NOS. Therefore,
caution should be used when deriving elevations for these marks.

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

                                                                                
Station ID: 8722429                         PUBLICATION DATE:  07/14/2009
Name:       HOBE SOUND BRIDGE, HOBE SOUND                     
            FL
NOAA Chart: 11474                           Latitude:   27°  3.9' N (  27.06500)
USGS Quad:  HOBE SOUND                      Longitude:  80°  7.4' W ( -80.12330)


                             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 8722429 HOBE SOUND BRIDGE, HOBE SOUND,

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