U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


To reach the tidal bench marks from the intersection of U.S. Highway 98 and
State Highway 363 in St. Marks, proceed west on U.S. Highway 98 for 3.2 km (2.0
mi) to Manatee Way, just before the bridge over Wakulla River, then turn right
and proceed NW on Manatee Way for 11 m (35 ft) to a fork in the road, then turn
left and proceed NW on Manatee Lane for 23 m (75 ft) to another fork, then turn
right and proceed NNW for 0.2 km (0.1 mi) to a private residence on the Wakulla
River.  The bench marks are located along U.S. Highway 98 and near the
residence.  The tide gage and staff were located on the bulkhead behind the
residence.


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


                 PRIMARY BENCH MARK STAMPING:  8171 A 1977
                         DESIGNATION:          872 8171 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8291
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  BE3967
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   30° 10.7' N (  30.17830)          LONGITUDE:  84° 14.8' W ( -84.24670)


The primary bench mark is a disk, located 13.26 m (43.5 ft) NNE of gate entrance
to the private residence, 7.35 m (24.1 ft) SW of the centerline of the sand
road, 6.61 m (21.7 ft) SSE of the NE fence corner of the property, and 0.76 m
(2.5 ft) east of a witness sign attached to the fence.  The bench mark is
crimped to the top of a copper-coated steel rod driven 2.4 m (8 ft) to refusal,
and encased in a 4-inch PVC pipe and concrete kickblock.

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

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


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


                         BENCH MARK STAMPING:  8171 B 1977
                         DESIGNATION:          872 8171 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8292
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  BE3969
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   30° 10.6' N (  30.17670)          LONGITUDE:  84° 14.7' W ( -84.24500)


The bench mark is a disk located NE of the NE end of the U.S. Highway 98 bridge
over the Wakulla River, 19 m (62 ft) NW of the centerline of U.S. Highway 98, 15
m (49 ft) NE of the centerline of Manatee Way, 6.95 m (22.8 ft) east of a 1 m (3
ft) diameter live oak tree, and 0.40 m (1.3 ft) SE of a metal witness post.  The
bench mark is crimped to the top of a copper-coated steel rod driven 4.9 m (16
ft) to refusal, and encased in a 4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  8171 C 1977
                         DESIGNATION:          872 8171 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8293
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  BE3968
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   30° 10.6' N (  30.17670)          LONGITUDE:  84° 14.7' W ( -84.24500)


The bench mark is a disk located near the NE end of the U.S. Highway 98 bridge
over the Wakulla River, 41.45 m (136.0 ft) NW of the centerline of U.S. Highway
98, 12 m (38 ft) NE of the edge of the swamp, and 0.40 m (1.3 ft) SE of a metal
witness post.  The bench mark is set 3 cm (0.1 ft) below ground level, crimped
to the top of a copper-coated steel rod driven 2.4 m (8 ft) 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  3 of  6

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


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


                         BENCH MARK STAMPING:  15.022
                         DESIGNATION:          15.022
                         ALIAS:                FLA SRD 15.022

MONUMENTATION:           Survey disk                           VM#:         8294
AGENCY:                  Florida State Road Department (FLSRD) IDB PID#:  BE1922
SETTING CLASSIFICATION:  Concrete bridge abutment              OPUS PID:        
LATITUDE:   30° 10.5' N (  30.17500)          LONGITUDE:  84° 14.7' W ( -84.24500)


The bench mark is a disk set in the top of the SE abutment at the SW end of the
U.S. Highway 98 bridge over the Wakulla River, 6 m (20 ft) SE of the centerline
of the highway, and 0.21 m (0.7 ft) above highway level.

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

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          NO STAMPING 1
                         ALIAS:                FLA SRD

MONUMENTATION:           Bench Mark disk                       VM#:         8295
AGENCY:                  Florida State Road Department (FLSRD) IDB PID#:  BE3970
SETTING CLASSIFICATION:  Concrete bridge abutment              OPUS PID:        
LATITUDE:   30° 10.6' N (  30.17670)          LONGITUDE:  84° 14.7' W ( -84.24500)


The bench mark is a disk set in the top of the NW abutment at the NE end of the
U.S. Highway 98 bridge over the Wakulla River, 6.16 m (20.2 ft) NW of the
centerline of the highway, 0.24 m (0.8 ft) above the level of the highway.

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

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


                            T I D A L   D A T U M S 


Tidal datums at WAKULLA RIVER based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           March 1977 - June 1977
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8728229 SHELL POINT, WALKER CREEK


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.344
     MEAN HIGH WATER                            MHW    =  0.310
     MEAN TIDE LEVEL                            MTL    =  0.183
     MEAN SEA LEVEL                             MSL    =  0.166
     MEAN LOW WATER                             MLW    =  0.056
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.352

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8171 A 1977                                 2.309    1.999
     8171 B 1977                                 1.727    1.417
     8171 C 1977                                 0.393    0.083
     15.022                                      4.053    3.743
     NO STAMPING 1                               4.058    3.748


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

                                                                                
Station ID: 8728171                         PUBLICATION DATE:  05/20/2004
Name:       WAKULLA RIVER                                     
            FL
NOAA Chart: 11405                           Latitude:   30° 10.6' N (  30.17670)
USGS Quad:  ST. MARKS                       Longitude:  84° 14.8' W ( -84.24670)


                             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.