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

                                                                                
Station ID: 8725259                         PUBLICATION DATE:  11/13/2003
Name:       LITTLE HICKORY BAY                                
            FL
NOAA Chart: 11426                           Latitude:   26° 19.8' N (  26.33000)
USGS Quad:  BONITA SPRINGS                  Longitude:  81° 50.3' W ( -81.83830)


To reach the tidal bench marks from the intersection of U.S. Highway 41 (South
Tamiami Trail) and Bonita Beach Road, proceed west on Bonita Beach Road for 3.5
km (2.2 mi) to Little Hickory Bay Bridge.  The bench marks are located on the
bridge and to the west of the bridge.  The tide gage and staff were located due
west of a two story apartment house NW of the bridge.


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


                 PRIMARY BENCH MARK STAMPING:  5259 C 1978
                         DESIGNATION:          872 5259 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7858
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD7881
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   26° 19.9' N (  26.33170)          LONGITUDE:  81° 50.3' W ( -81.83830)


The primary bench mark is a disk set in the top of a concrete monument west of
the bridge, 79 m (258 ft) west of Bench Mark 5259 B 1978, 61 m (200 ft) west of
the  west end of the bridge, 17.65 m (57.9 ft) north of the centerline of Bonita
Beach Road, and 0.37 m (1.2 ft) west of a utility pole.  NOTE: Mark not found by
US Power Squadron in 1998 and 1999.

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

                                                                                
Station ID: 8725259                         PUBLICATION DATE:  11/13/2003
Name:       LITTLE HICKORY BAY                                
            FL
NOAA Chart: 11426                           Latitude:   26° 19.8' N (  26.33000)
USGS Quad:  BONITA SPRINGS                  Longitude:  81° 50.3' W ( -81.83830)


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


                         BENCH MARK STAMPING:  Z 245 1 5259
                         DESIGNATION:          Z 245

MONUMENTATION:           Survey disk                           VM#:         7855
AGENCY:                  Florida State Road Department (FLSRD) IDB PID#:  AD1301
SETTING CLASSIFICATION:  Concrete bridge                       OPUS PID:        
LATITUDE:   26° 19.8' N (  26.33000)          LONGITUDE:  81° 50.2' W ( -81.83670)


The bench mark is a disk set in the NE corner of the bridge, 5.61 m (18.4 ft)
north of the centerline of Bonita Beach Road, and about level with the road. 
NOTE: Mark not found by US Power Squadron in 1998.



                         BENCH MARK STAMPING:  5259 B 1978
                         DESIGNATION:          872 5259 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7857
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD7880
SETTING CLASSIFICATION:  Sea wall                              OPUS PID:        
LATITUDE:   26° 19.9' N (  26.33170)          LONGITUDE:  81° 50.2' W ( -81.83670)


The bench mark is a disk set flush in a sea wall north of the bridge, 34 m (112
ft) south of the NE corner of the sea wall, 15 m (50 ft) north of the west end
of the bridge, 4.94 m (16.2 ft) SE of the SE corner of a real estate office, and
0.30 m (1.0 ft) north of the south end of the sea wall.  NOTE: Mark not found by
US Power Squadron in 1999.

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

                                                                                
Station ID: 8725259                         PUBLICATION DATE:  11/13/2003
Name:       LITTLE HICKORY BAY                                
            FL
NOAA Chart: 11426                           Latitude:   26° 19.8' N (  26.33000)
USGS Quad:  BONITA SPRINGS                  Longitude:  81° 50.3' W ( -81.83830)


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


                         BENCH MARK STAMPING:  5259 D 1978
                         DESIGNATION:          872 5259 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7859
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   26° 19.8' N (  26.33000)          LONGITUDE:  81° 50.3' W ( -81.83830)


The bench mark is a disk located 104 m (340 ft) west of Bench Mark 5259 C 1978,
17.34 m (56.9 ft) north of the centerline of Bonita Beach Road, 0.37 m (1.2 ft)
south of United System utility pole #2065, and 0.15 m (0.5 ft) south of a
witness sign.  The bench mark is 0.09 m (0.3 ft) above the ground, crimped to
the top of a galvanized steel rod driven 11.0 m (36 ft) to refusal, and encased
in a 4-inch PVC pipe.

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

                                                                                
Station ID: 8725259                         PUBLICATION DATE:  11/13/2003
Name:       LITTLE HICKORY BAY                                
            FL
NOAA Chart: 11426                           Latitude:   26° 19.8' N (  26.33000)
USGS Quad:  BONITA SPRINGS                  Longitude:  81° 50.3' W ( -81.83830)


                            T I D A L   D A T U M S 


Tidal datums at LITTLE HICKORY BAY based on:

     LENGTH OF SERIES:      6 MONTHS
     TIME PERIOD:           March 1978 - August 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8725235 WIGGINS PASS, INSIDE


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.256
     North American Vertical Datum              NAVD88 =  0.214
     MEAN HIGH WATER                            MHW    =  0.207
     MEAN TIDE LEVEL                            MTL    =  0.122
     MEAN SEA LEVEL                             MSL    =  0.118
     MEAN LOW WATER                             MLW    =  0.036
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5259 C 1978                                 1.332    1.125
     Z 245 1 5259                                4.723    4.516
     5259 B 1978                                 1.045    0.838
     5259 D 1978                                 1.142    0.935


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

                                                                                
Station ID: 8725259                         PUBLICATION DATE:  11/13/2003
Name:       LITTLE HICKORY BAY                                
            FL
NOAA Chart: 11426                           Latitude:   26° 19.8' N (  26.33000)
USGS Quad:  BONITA SPRINGS                  Longitude:  81° 50.3' W ( -81.83830)


                             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.