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Bench Mark Sheet for 8724493, BOCA CHICA MARINA 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  7

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


To reach the tidal bench marks from gate No. 2 at the Boca Chica Naval Air
Station, proceed south on a black-topped road for 1.0 km (0.6 mi) to the Boca
Chica Marina. The bench marks are in the vicinity of the marina and along the
road. The tide gauge was located along the bulkhead near the picnic area.


                         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  7

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


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


                 PRIMARY BENCH MARK STAMPING:  N 329 1970
                         DESIGNATION:          N 329

MONUMENTATION:           Bench Mark disk                       VM#:        16097
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AA0086
SETTING CLASSIFICATION:  Concrete base of manhole              OPUS PID:        
LATITUDE:   24° 34.3' N (  24.57170)          LONGITUDE:  81° 42.2' W ( -81.70330)


The primary bench mark is a disk set on top of the west side of a 2x2 m (7x7 ft)
concrete base with large iron manhole cover, near the west end of the east-west
runway at Boca Chica Naval Air Station, 94 m (307 ft) north of the extended
centerline of the east-west runway, 6.71 m (22.0 ft) west of the centerline of
the north-south street, 0.12 m (0.4 ft) east of the west edge of the base, 0.09
m (0.3 ft) above the ground level and level with the street.

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

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


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


                         BENCH MARK STAMPING:  H 329 1970
                         DESIGNATION:          H 329

MONUMENTATION:           Bench Mark disk                       VM#:        16098
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AA0070
SETTING CLASSIFICATION:  Loading platform                      OPUS PID:        
LATITUDE:   24° 34.9' N (  24.58170)          LONGITUDE:  81° 42.8' W ( -81.71330)


The bench mark is a disk set on top of the east end of the loading ramp along
the north side of building No. A 1116 at the weapons storage area at Boca Chica
Naval Air Station, 49.96 m (163.9 ft) east of bench mark J 329 1970, 6.86 m
(22.5 ft) NW of the NE corner of the building, 4 m (12 ft) north of the north
face of the building, 0.18 m (0.6 ft) south of the north edge of platform, 0.15
m (0.5 ft) west of the east end of the ramp, and 1.07 m (3.5 ft) above ground
level.

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

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


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


                         BENCH MARK STAMPING:  J 329 1970
                         DESIGNATION:          J 329

MONUMENTATION:           Bench Mark disk                       VM#:        16099
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AA0069
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   24° 34.9' N (  24.58170)          LONGITUDE:  81° 42.8' W ( -81.71330)


The bench mark is a disk set on the top of the north end of the top step of 5
steps leading to top of loading dock for building A 1116, at the weapons storage
area at Boca Chica Naval Air Station, 5 m (18 ft) east of the NW corner of the
building, 1.10 m (3.6 ft) north of the north face of the building, 0.3 m (1 ft)
south of the north end of the step, and 0.82 m (2.7 ft) above ground level.



                         BENCH MARK STAMPING:  4499 M 2000
                         DESIGNATION:          872 4499 M

MONUMENTATION:           Tidal Station disk                    VM#:        16100
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   24° 34.5' N (  24.57500)          LONGITUDE:  81° 42.5' W ( -81.70830)


The bench mark is a disk set in top of a concrete bulkhead at Boca Chica Marina
at Boca Chica Naval Air Station, about 0.64 km (0.40 mi) from gate No. 2 along a
black-topped road, 29.87 m (98.0 ft) NW of the NE corner of Building No. 1132,
16.30 m (53.5 ft) NE of the SW corner of the bulkhead, and 2.60 m (8.53 ft) SE
of the NW corner of the bulkhead.

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

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


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


                         BENCH MARK STAMPING:  4499 N 2000
                         DESIGNATION:          872 4499 N

MONUMENTATION:           Tidal Station disk                    VM#:        16101
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Manhole foundation                    OPUS PID:        
LATITUDE:   24° 34.4' N (  24.57330)          LONGITUDE:  81° 42.3' W ( -81.70500)


The bench mark is a disk set in a large concrete foundation for a manhole near a
pump station at Boca Chica Naval Air Station, 0.72 km (0.45 mi) along a black
topped road from gate No.2, 9.64 m (31.6 ft) NE of the NE corner of Building
No.1103, and 8.80 m (28.9 ft) NNW of the NE corner of Building No.1332.



                         BENCH MARK STAMPING:  4499 P 2000
                         DESIGNATION:          872 4499 P

MONUMENTATION:           Tidal Station disk                    VM#:        16102
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Large utility foundation              OPUS PID:        
LATITUDE:   24° 34.3' N (  24.57170)          LONGITUDE:  81° 42.3' W ( -81.70500)


The bench mark is set in a large concrete foundation at Boca Bhica Naval Air
Station, about 0.72 km (0.45 mi) from gate No.2 along a black-topped road at the
intersection of two black-topped roads, 30.78 m (101.0 ft) SSW of a transformer,
5.35 m (17.6 ft) SW of the SW corner of the concrete sign foundation, 3.19 m
(10.5 ft) SE of the west corner of the concrete foundation.

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

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


                            T I D A L   D A T U M S 


Tidal datums at BOCA CHICA MARINA based on:

     LENGTH OF SERIES:      3 Months
     TIME PERIOD:           March 2000 - May 2000
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8724580 KEY WEST


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

     North American Vertical Datum              NAVD88 =  0.438
     MEAN HIGHER HIGH WATER                     MHHW   =  0.381
     MEAN HIGH WATER                            MHW    =  0.305
     MEAN SEA LEVEL                             MSL    =  0.200
     MEAN TIDE LEVEL                            MTL    =  0.178
     MEAN LOW WATER                             MLW    =  0.052
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     N 329 1970                                  1.224    0.919
     H 329 1970                                  2.901    2.596
     J 329 1970                                  2.764    2.459
     4499 M 2000                                 1.776    1.471
     4499 N 2000                                 2.039    1.734
     4499 P 2000                                 1.355    1.050


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

                                                                                
Station ID: 8724493                         PUBLICATION DATE:  04/21/2003
Name:       BOCA CHICA MARINA                                 
            FL
NOAA Chart: 11445                           Latitude:   24° 34.5' N (  24.57500)
USGS Quad:  BOCA CHICA KEY                  Longitude:  81° 42.5' W ( -81.70830)


                             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 8724493 BOCA CHICA MARINA, FL

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