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

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


To reach the tidal bench marks from the intersection of U.S. Highway 98 and
State Route 295 (Navy Boulevard), proceed west on U.S. Highway 98  for 14.0 km
(8.7 mi) to Perdido Manor Road, then turn left and proceed south on Perdido
Manor Drive for 0.6 km (0.4 mi) to the J.E. Mattis residence.  The bench marks
are at the Mattis residence and along U.S. Highway 98.  The tide gage and staff
were located on the dock at the Mattis residence.


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


                 PRIMARY BENCH MARK STAMPING:  1 1973
                         DESIGNATION:          872 9962 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:        10327
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BG3410
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   30° 23.7' N (  30.39500)          LONGITUDE:  87° 25.4' W ( -87.42330)


The primary bench mark is a disk set in the top of a concrete sea wall, 101 m
(330 ft) west of the NW corner of the Mattis house, 4.27 m (14.0 ft) east of the
east end of a wood pier, 1.71 m (5.6 ft) west of a post with flood lights, and
0.61 m (2.0 ft) south of a witness post.

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

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


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


                         BENCH MARK STAMPING:  2 1973
                         DESIGNATION:          872 9962 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:        10328
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  BG3409
SETTING CLASSIFICATION:  Concrete walkway                      OPUS PID:        
LATITUDE:   30° 23.8' N (  30.39670)          LONGITUDE:  87° 25.4' W ( -87.42330)


The bench mark is a disk set in top of the concrete walkway in front of the
Mattis house, 41 m (135 ft) SW of the centerline of Perdido Manor Road, 1.98 m
(6.5 ft) NE of the north side of the garage, 0.76 m (2.5 ft) east of east
walkway at the Mattis house, and 0.12 m (0.4 ft) south of the porch.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


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


                         BENCH MARK STAMPING:  K 5 1940
                         DESIGNATION:          K 5 USGS

MONUMENTATION:           Bench Mark disk                       VM#:        10331
AGENCY:                  US Geological Survey (USGS)           IDB PID#:  BG3406
SETTING CLASSIFICATION:  Concrete culvert head wall            OPUS PID:        
LATITUDE:   30° 23.9' N (  30.39830)          LONGITUDE:  87° 25.0' W ( -87.41670)


The bench mark is a disk set in top of a concrete culvert head wall, 36.58 m
(120.0 ft) SW of the SW corner of house # 318 (U.S. Highway 98), 26.82 m (88.0
ft) NW of telephone pole # LH 187, 6.19 m (20.3 ft) NW of a fence corner, 5.49 m
(18.0 ft) south of the centerline of U.S. Highway 98, and 1.37 m (4.5 ft) west
of a witness post.



                         BENCH MARK STAMPING:  9962 D 1993
                         DESIGNATION:          872 9962 D

MONUMENTATION:           Tidal Station disk                    VM#:        16555
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete driveway                     OPUS PID:        
LATITUDE:   30° 23.7' N (  30.39500)          LONGITUDE:  87° 25.5' W ( -87.42500)


The bench mark is a disk set flush in the concrete driveway at 1130 Spanish Moss
Drive, 30.72 m (100.8 ft) east of the centerline of Perdido Manor Drive, 14.66 m
(48.1 ft) south of the SW corner of the house, and 6.37 m (20.9 ft) north of the
centerline of Spanish Moss Drive.

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

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


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


                         BENCH MARK STAMPING:  9962 E 1993
                         DESIGNATION:          872 9962 E

MONUMENTATION:           Tidal Station disk                    VM#:        16556
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete driveway                     OPUS PID:        
LATITUDE:   30° 23.7' N (  30.39500)          LONGITUDE:  87° 25.5' W ( -87.42500)


The bench mark is a disk set flush in the concrete driveway at 1070 Spanish Moss
Drive, 10.21 m (33.5 ft) south of the centerline of Spanish Moss Drive, 6.34 m
(20.8 ft) east of the city water meter cover, 17.10 m (56.1 ft) north of the NE
corner of the house at the residence of J. R. Van Landingham.



                         BENCH MARK STAMPING:  9962 G 1984
                         DESIGNATION:          872 9962 G TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        16558
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  BG3647
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   30° 24.0' N (  30.40000)          LONGITUDE:  87° 25.4' W ( -87.42330)


The bench mark is a disk located 0.3 km (0.2 mi) SE of bench mark 9962 F, 10.39
m (34.1 ft) SW of the centerline of U.S. Highway 98, 8.90 m (29.2 ft) SE of the
centerline of Perdido Manor Road, 3.05 m (10.0 ft) east of a 0.3 m (1 ft)
diameter pine tree, 0.67 m (2.2 ft) SW of a metal right-of-way marker, and 0.37
m (1.2 ft) NE of a witness post.  The bench mark is crimped to the top of a
stainless steel rod driven 15.5 m (51.0 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  5 of  6

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


                            T I D A L   D A T U M S 


Tidal datums at PERDIDO BAY based on:

     LENGTH OF SERIES:      5 Years
     TIME PERIOD:           June 1973 - May 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8729840 PENSACOLA, PENSACOLA BAY


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

     HIGHEST OBSERVED WATER LEVEL (02/11/1994)         =  0.397
     MEAN HIGHER HIGH WATER                     MHHW   =  0.218
     MEAN HIGH WATER                            MHW    =  0.214
     MEAN TIDE LEVEL                            MTL    =  0.108
     MEAN SEA LEVEL                             MSL    =  0.105
     MEAN LOW WATER                             MLW    =  0.003
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.012
     LOWEST  OBSERVED WATER LEVEL (02/01/1994)         = -0.274

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1 1973                                      0.563    0.349
     2 1973                                      3.365    3.151
     K 5 1940                                    6.519    6.305
     9962 D 1993                                 3.278    3.064
     9962 E 1993                                 3.306    3.091
     9962 G 1984                                 1.906    1.692


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

                                                                                
Station ID: 8729962                         PUBLICATION DATE:  09/16/2003
Name:       PERDIDO BAY                                       
            FL
NOAA Chart: 11382                           Latitude:   30° 23.6' N (  30.39330)
USGS Quad:  LILLIAN                         Longitude:  87° 25.5' W ( -87.42500)


                             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.