U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8724970                         PUBLICATION DATE:  02/05/2004
Name:       FAKA UNION BAY                                    
            FL
NOAA Chart: 11429                           Latitude:   25° 54.2' N (  25.90330)
USGS Quad:  ROYAL PALM HAMMOCK              Longitude:  81° 30.8' W ( -81.51330)


To reach the tidal bench marks from the Remuda Ranch Marina on State Highway 91,
proceed by boat from the Marina along the Faka Union River to the mouth of the
river at the Faka Union Bay.  The tide gage and staff were SW of the mouth of
the river.  The bench marks are located NW of the gage site, marker NO. 51, and
along a path leading through the mangrove.


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


                 PRIMARY BENCH MARK STAMPING:  4970 A 1978
                         DESIGNATION:          872 4970 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9738
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   25° 54.2' N (  25.90330)          LONGITUDE:  81° 30.8' W ( -81.51330)


The primary bench mark is a disk located 110 m (360 ft) NW of channel marker NO.
51, 18.78 m (61.6 ft) west of the mangrove line, 0.15 m (0.5 ft) north of a
witness post.  The bench mark is 0.24 m (0.8 ft) above ground level, crimped to
the top of a copper-clad steel rod driven 9.8 m (32 ft) to substantial
resistance and encased in a steel pipe and concrete kickblock.

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

                                                                                
Station ID: 8724970                         PUBLICATION DATE:  02/05/2004
Name:       FAKA UNION BAY                                    
            FL
NOAA Chart: 11429                           Latitude:   25° 54.2' N (  25.90330)
USGS Quad:  ROYAL PALM HAMMOCK              Longitude:  81° 30.8' W ( -81.51330)


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


                         BENCH MARK STAMPING:  4970 B 1978
                         DESIGNATION:          872 4970 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9739
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   25° 54.2' N (  25.90330)          LONGITUDE:  81° 30.8' W ( -81.51330)


The bench mark is a disk located NW of the gage site, 28.35 m (93.0 ft) west of
the mangrove edge, 13.20 m (43.3 ft) north of bench mark 4970 A 1978, and 0.24 m
(0.8 ft) SE of a witness post.  The bench mark is 0.27 m (0.9 ft) above ground
level, crimped to the top of a copper-clad steel rod driven 9.8 m (32 ft) to
substantial resistance and encased in a steel pipe and concrete kickblock.  



                         BENCH MARK STAMPING:  4970 C 1978
                         DESIGNATION:          872 4970 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9740
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   25° 54.2' N (  25.90330)          LONGITUDE:  81° 30.8' W ( -81.51330)


The bench mark is a disk located NW of the gage site, 10.79 m (35.4 ft) WNW of
bench mark 4970 B 1978, and 0.24 m (0.8 ft) SE of a witness post. The bench mark
is 0.34 m (1.1 ft) above ground level, crimped to the top of a copper-clad steel
rod driven 9.8 m (32 ft) to substantial resistance and encased in a steel pipe
and concrete kickblock.

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

                                                                                
Station ID: 8724970                         PUBLICATION DATE:  02/05/2004
Name:       FAKA UNION BAY                                    
            FL
NOAA Chart: 11429                           Latitude:   25° 54.2' N (  25.90330)
USGS Quad:  ROYAL PALM HAMMOCK              Longitude:  81° 30.8' W ( -81.51330)


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


                         BENCH MARK STAMPING:  4970 D 1978
                         DESIGNATION:          872 4970 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9741
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   25° 54.2' N (  25.90330)          LONGITUDE:  81° 30.8' W ( -81.51330)


The bench mark is a disk located NW of the gage site, 46 m (150 ft) west of the
mangrove line, 13.75 m (45.1 ft) WSW of bench mark 4970 C 1978, and 0.27 m (0.9
ft) SE of a witness post. The bench mark is 15 cm (0.5 ft) above ground level,
crimped to the top of a copper-clad steel rod driven 9.8 m (32 ft) to
substantial resistance and encased in a steel pipe and concrete kickblock.  



                         BENCH MARK STAMPING:  4970 E 1978
                         DESIGNATION:          872 4970 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9742
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   25° 54.2' N (  25.90330)          LONGITUDE:  81° 30.8' W ( -81.51330)


The bench mark is a disk located NW of the gage site, 42.67 m (140.0 ft) NW of
the mangrove line, 17.50 m (57.4 ft) SW of bench mark 4970 D 1978, and 0.24 m
(0.8 ft) NNE of a witness post.  The bench mark is 0.12 m (0.4 ft) above ground
level, crimped to the top of a copper-clad steel rod driven 9.8 m (32 ft) to
substantial resistance and encased in a steel pipe and concrete kickblock.

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

                                                                                
Station ID: 8724970                         PUBLICATION DATE:  02/05/2004
Name:       FAKA UNION BAY                                    
            FL
NOAA Chart: 11429                           Latitude:   25° 54.2' N (  25.90330)
USGS Quad:  ROYAL PALM HAMMOCK              Longitude:  81° 30.8' W ( -81.51330)


                            T I D A L   D A T U M S 


Tidal datums at FAKA UNION BAY based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           December 1977 - March 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8725110 NAPLES, GULF OF MEXICO


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.853
     MEAN HIGH WATER                            MHW    =  0.775
     MEAN TIDE LEVEL                            MTL    =  0.440
     MEAN SEA LEVEL                             MSL    =  0.418
     MEAN LOW WATER                             MLW    =  0.105
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4970 A 1978                                 0.884    0.109
     4970 B 1978                                 0.984    0.209
     4970 C 1978                                 1.085    0.310
     4970 D 1978                                 0.995    0.220
     4970 E 1978                                 0.958    0.183


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

                                                                                
Station ID: 8724970                         PUBLICATION DATE:  02/05/2004
Name:       FAKA UNION BAY                                    
            FL
NOAA Chart: 11429                           Latitude:   25° 54.2' N (  25.90330)
USGS Quad:  ROYAL PALM HAMMOCK              Longitude:  81° 30.8' W ( -81.51330)


                             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.