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Bench Mark Sheet for 8724947, CAPE ROMANO ISLAND 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8724947                         PUBLICATION DATE:  02/05/2004
Name:       CAPE ROMANO ISLAND                                
            FL
NOAA Chart: 11429                           Latitude:   25° 51.2' N (  25.85330)
USGS Quad:  CAPE ROMANO                     Longitude:  81° 40.5' W ( -81.67500)


To reach the tidal bench marks from the County Road 953 bridge over Big Marco
River at Goodland, proceed by boat in a southerly direction for 5 km (3 statute
mi) through the marked channel to Day Beacon "R2", then SW for 4.0 km (2.9 nm)
to a small cottage on pilings with a dock on the west shore of Cape Romano
Island.  The bench marks are in the vicinity of the cottage owned by Mr. Ted
Currie and to the south of the dock.  The tide gage and staff were located on
the dock.


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


                 PRIMARY BENCH MARK STAMPING:  4947 A 1978
                         DESIGNATION:          872 4947 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9705
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   25° 51.2' N (  25.85330)          LONGITUDE:  81° 40.5' W ( -81.67500)


The primary bench mark is a disk located 8.26 m (27.1 ft) NW of the NE corner of
the cottage, 8.05 m (26.4 ft) NE of the NW corner of the cottage, and 0.24 m
(0.8 ft) south of a witness post.  The bench mark is set 0.30 m (1.0 ft) above
ground level, crimped to the top of an unspecified steel rod driven 9.8 m (32
ft) to resistance and encased in a 4-inch steel pipe projecting 0.40 m (1.3 ft).

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8724947                         PUBLICATION DATE:  02/05/2004
Name:       CAPE ROMANO ISLAND                                
            FL
NOAA Chart: 11429                           Latitude:   25° 51.2' N (  25.85330)
USGS Quad:  CAPE ROMANO                     Longitude:  81° 40.5' W ( -81.67500)


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


                         BENCH MARK STAMPING:  4947 B 1978
                         DESIGNATION:          872 4947 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9706
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   25° 51.2' N (  25.85330)          LONGITUDE:  81° 40.5' W ( -81.67500)


The bench mark is a disk located 47 m (154 ft) WNW of bench mark 4947 A 1978,
5.43 m (17.8 ft) east of the east end of a canal, and 0.40 m (1.3 ft) east of a
witness post.  The bench mark is set 0.27 m (0.9 ft) above ground level, crimped
to the top of an unspecified steel rod driven 9.8 m (32 ft) to resistance and
encased in a 4-inch steel pipe projecting 0.46 m (1.5 ft).



                         BENCH MARK STAMPING:  4947 C 1978
                         DESIGNATION:          872 4947 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9707
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   25° 51.2' N (  25.85330)          LONGITUDE:  81° 40.5' W ( -81.67500)


The bench mark is a disk located 48.77 m (160.0 ft) south of bench mark 4947 B
1978, 24 m (80 ft) west of the approximate shoreline, and 0.40 m (1.3 ft) NNE of
a witness post.  The bench mark is set 0.18 m (0.6 ft) above ground level,
crimped to the top of an unspecified steel rod driven 9.8 m (32 ft) to
resistance and encased in a 4-inch steel pipe projecting 0.37 m (1.2 ft).

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8724947                         PUBLICATION DATE:  02/05/2004
Name:       CAPE ROMANO ISLAND                                
            FL
NOAA Chart: 11429                           Latitude:   25° 51.2' N (  25.85330)
USGS Quad:  CAPE ROMANO                     Longitude:  81° 40.5' W ( -81.67500)


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


                         BENCH MARK STAMPING:  4947 D 1978
                         DESIGNATION:          872 4947 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9708
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   25° 51.2' N (  25.85330)          LONGITUDE:  81° 40.5' W ( -81.67500)


The bench mark is a disk located  69.19 m (227.0 ft) SSW of bench mark 4947 C
1978, 23 m (75 ft) NW of the approximate shoreline, and 0.3 m (1 ft) NNE of a
witness post.  The bench mark is set 0.37 m (1.2 ft) above ground level, crimped
to the top of an unspecified steel rod driven 9.8 m (32 ft) to resistance and
encased in a 4-inch steel pipe projecting 0.46 m (1.5 ft).



                         BENCH MARK STAMPING:  4947 E 1978
                         DESIGNATION:          872 4947 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9709
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   25° 51.2' N (  25.85330)          LONGITUDE:  81° 40.5' W ( -81.67500)


The bench mark is a disk located 88 m (289 ft) SSW of bench mark 4947 D 1978, 17
m (55 ft) NNE of the NW corner of a shanty on pilings, 4.94 m (16.2 ft) ENE of a
0.21 m (0.7 ft) diameter Sabal palm, and 0.40 m (1.3 ft) east of a witness post.
 The bench mark is set 0.24 m (0.8 ft) above ground level, crimped to the top of
an unspecified steel rod driven 9.8 m (32 ft) to resistance and encased in a
4-inch steel pipe projecting 0.30 m (1.0 ft).

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8724947                         PUBLICATION DATE:  02/05/2004
Name:       CAPE ROMANO ISLAND                                
            FL
NOAA Chart: 11429                           Latitude:   25° 51.2' N (  25.85330)
USGS Quad:  CAPE ROMANO                     Longitude:  81° 40.5' W ( -81.67500)


                            T I D A L   D A T U M S 


Tidal datums at CAPE ROMANO ISLAND based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           May 1978 - August 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8724919 CHOKOLOSKEE


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.049
     MEAN HIGH WATER                            MHW    =  0.975
     MEAN TIDE LEVEL                            MTL    =  0.579
     MEAN SEA LEVEL                             MSL    =  0.559
     MEAN LOW WATER                             MLW    =  0.183
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4947 A 1978                                 1.668    0.693
     4947 B 1978                                 2.315    1.340
     4947 C 1978                                 2.174    1.199
     4947 D 1978                                 2.018    1.043
     4947 E 1978                                 1.761    0.786


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

                                                                                
Station ID: 8724947                         PUBLICATION DATE:  02/05/2004
Name:       CAPE ROMANO ISLAND                                
            FL
NOAA Chart: 11429                           Latitude:   25° 51.2' N (  25.85330)
USGS Quad:  CAPE ROMANO                     Longitude:  81° 40.5' W ( -81.67500)


                             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 8724947 CAPE ROMANO ISLAND, FL

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