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Bench Mark Sheet for 8726573, GADSDEN POINT, TAMPA 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


To reach the tidal bench marks in Tampa, proceed to MacDill Air Force Base.  The
bench marks are located along Marina Drive.  The tide gage and staff were
located on the MacDill Air Force Base Marina pier.


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


                 PRIMARY BENCH MARK STAMPING:  NO 4 1975
                         DESIGNATION:          872 6573 TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:         6573
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AG7535
SETTING CLASSIFICATION:  Concrete manhole collar               OPUS PID:        
LATITUDE:   27° 50.3' N (  27.83830)          LONGITUDE:  82° 29.2' W ( -82.48670)


The primary bench mark is a disk set flush in the NE corner of a concrete
manhole collar, near the intersection of Marina Drive and South Shore Road, 88 m
(290 ft) SE of bench mark Bunker 2 1956, 20 m (65 ft) NE of a "30 MPH" sign, and
7.80 m (25.6 ft) east of the centerline of Marina Drive.



                         BENCH MARK STAMPING:  NO 2 1975
                         DESIGNATION:          872 6573 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:         6571
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   27° 49.3' N (  27.82170)          LONGITUDE:  82° 29.1' W ( -82.48500)


The bench mark is a disk located 53 m (174 ft) north of the NE corner of the
Snack Bar (Building 692), 4 m (14 ft) north of the centerline of Flagpole Road,
52 m (171 ft) west of Tinker Avenue and Flagpole Road, and 0.49 m (1.6 ft) west
of power pole No. 4-24.  The bench mark is set level with the ground, crimped to
the top of a copper-clad steel rod driven an unspecified depth to refusal, and
encased in a PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


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


                         BENCH MARK STAMPING:  F3-3X 1975
                         DESIGNATION:          F 3 3 X USE

MONUMENTATION:           Bench Mark disk                       VM#:         6574
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  AG7536
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   27° 49.7' N (  27.82830)          LONGITUDE:  82° 29.2' W ( -82.48670)


The bench mark is a disk set in the top of a concrete post, 15.64 m (51.3 ft)
NNW of a utility pole, 4 m (14 ft) NW of a pine tree with a witness post
attached, 4.21 m (13.8 ft) east of the centerline of Marina Drive, 0.37 m (1.2
ft) east of the east edge of the road, and 0.15 m (0.5 ft) below ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


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


                         BENCH MARK STAMPING:  TH-110 1975
                         DESIGNATION:          TH 110 USE

MONUMENTATION:           Bench Mark disk                       VM#:         6575
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  AG7539
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   27° 49.4' N (  27.82330)          LONGITUDE:  82° 29.1' W ( -82.48500)


The bench mark is a disk set flush in the west concrete sea wall at the MacDill
Air Force Base Marina (Building 663), 36 m (118 ft) SSE of the NW corner of the
boat basin, and 23.62 m (77.5 ft) north of the NE corner of Building 663.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


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


                         BENCH MARK STAMPING:  BUNKER 2 1956
                         DESIGNATION:          BUNKER 2

MONUMENTATION:           Traverse Station disk                 VM#:         6576
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG6114
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   27° 50.3' N (  27.83830)          LONGITUDE:  82° 29.2' W ( -82.48670)


The bench mark is a disk at the SW corner of the intersection of South Shore
Road and Marina Drive, 10.18 m (33.4 ft) west of the centerline of Marina Drive,
5 m (18 ft) south of the centerline of South Shore Road, 0.15 m (0.5 ft) north
of the wing wall of a culvert at a point of the west wing, and 6 cm (0.2 ft)
below ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


                            T I D A L   D A T U M S 


Tidal datums at GADSDEN POINT, TAMPA BAY based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           December 1975 - December 1975
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8726520 ST. PETERSBURG, TAMPA BAY


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.750
     MEAN HIGH WATER                            MHW    =  0.674
     North American Vertical Datum              NAVD88 =  0.493
     MEAN SEA LEVEL                             MSL    =  0.415
     MEAN TIDE LEVEL                            MTL    =  0.397
     MEAN LOW WATER                             MLW    =  0.120
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 4 1975                                   2.059    1.385
     NO 2 1975                                   2.060    1.386
     F3-3X 1975                                  2.002    1.328
     TH-110 1975                                 1.864    1.190
     BUNKER 2 1956                               2.222    1.548


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

                                                                                
Station ID: 8726573                         PUBLICATION DATE:  02/13/2004
Name:       GADSDEN POINT, TAMPA BAY                          
            FL
NOAA Chart: 11412                           Latitude:   27° 49.3' N (  27.82170)
USGS Quad:  GIBSONTON                       Longitude:  82° 29.1' W ( -82.48500)


                             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 8726573 GADSDEN POINT, TAMPA BAY, FL

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