U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


To reach the tidal bench marks from the main entrance to the Pensacola Naval Air
Station, proceed 2.33 km (1.45 mi) SE on Murry Boulevard to Saufley Street, then
turn left and proceed east on Saufley Street for 0.5 km (0.3 mi) to East Avenue,
then turn right and proceed south on East Avenue for 0.5 km (0.3 mi) to Dallas
Avenue, then turn right and proceed 0.40 km (0.25 mi) west on Dallas Avenue to
Building No. 75 on the south side of Dallas Avenue.  The bench marks are located
in area along Dallas Avenue and the sea wall.  The tide gage and staff were
located on a concrete dock south of building No. 75.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


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


                 PRIMARY BENCH MARK STAMPING:  7.792 K 9 1918
                         DESIGNATION:          K 9

MONUMENTATION:           Bench Mark disk                       VM#:        10281
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BG1813
SETTING CLASSIFICATION:  Brick wall                            OPUS PID:        
LATITUDE:   30° 20.8' N (  30.34670)          LONGITUDE:  87° 16.3' W ( -87.27170)


The primary bench mark is a disk set vertically in the west face of a brick wall
between Jayne and West Avenues, 18.75 m (61.5 ft) east and across Jayne Avenue
from the SE corner of building No. 216, 11.58 m (38.0 ft) north of the
centerline of Dallas Street, 6.40 m (21.0 ft) east of the centerline of Jayne
Avenue, and 0.30 m (1.0 ft) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


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


                         BENCH MARK STAMPING:  7.507 L 9 1918
                         DESIGNATION:          L 9

MONUMENTATION:           Bench Mark disk                       VM#:        10282
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BG1814
SETTING CLASSIFICATION:  Building wall                         OPUS PID:        
LATITUDE:   30° 20.7' N (  30.34500)          LONGITUDE:  87° 16.2' W ( -87.27000)


The bench mark is a disk set vertically in the north face of building No. 27, 91
m (300 ft) SSE of the junction of South and West Avenues, 78 m (255 ft) south of
the centerline of South Avenue, 0.27 m (0.9 ft) west of the NE corner of
building No. 27, and 0.61 m (2.0 ft) above the level of the pavement.



                         BENCH MARK STAMPING:  NO 1 1934
                         DESIGNATION:          872 9868 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:        10283
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BG1815
SETTING CLASSIFICATION:  Concrete curb                         OPUS PID:        
LATITUDE:   30° 20.7' N (  30.34500)          LONGITUDE:  87° 16.1' W ( -87.26830)


The bench mark is a disk set the in top of the concrete curb of the south
foundation of building No. 71, 87 m (285 ft) south of the centerline of South
Avenue, 9.14 m (30.0 ft) north of the sea wall on the north shore of Pensacola
Bay, and 0.15 m (0.5 ft) above pavement level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


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


                         BENCH MARK STAMPING:  B 161 1955
                         DESIGNATION:          B 161

MONUMENTATION:           Bench Mark disk                       VM#:        10284
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BG1810
SETTING CLASSIFICATION:  Concrete pillar                       OPUS PID:        
LATITUDE:   30° 20.9' N (  30.34830)          LONGITUDE:  87° 16.6' W ( -87.27670)


The bench mark is a disk set vertically in the west face of a large concrete
pillar at the SW corner of the porch of building No. 624, at the junction of
Fisher Avenue and Dallas Street, on the south side of the building, 0.30 m (1.0
ft) north of the SW corner of the porch, and 0.55 m (1.8 ft) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


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


                         BENCH MARK STAMPING:  C 161 1955
                         DESIGNATION:          C 161

MONUMENTATION:           Bench Mark disk                       VM#:        10285
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  BG1809
SETTING CLASSIFICATION:  Building foundation                   OPUS PID:        
LATITUDE:   30° 20.8' N (  30.34670)          LONGITUDE:  87° 16.8' W ( -87.28000)


The bench mark is a disk set vertically in the north face of the concrete
foundation of building No. 632, 5.49 m (18.0 ft) south of the south curb of
Dallas Street, 0.46 m (1.5 ft) west of the NE corner of the building, and 0.61 m
(2.0 ft) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


                            T I D A L   D A T U M S 


Tidal datums at PENSACOLA, NAVAL AIR STATION based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           March 1977 - June 1977
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8729840 PENSACOLA, PENSACOLA BAY


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.364
     MEAN HIGH WATER                            MHW    =  0.354
     MEAN TIDE LEVEL                            MTL    =  0.183
     MEAN SEA LEVEL                             MSL    =  0.177
     North American Vertical Datum              NAVD88 =  0.086
     MEAN LOW WATER                             MLW    =  0.011
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7.792 K 9 1918                              2.403    2.049
     7.507 L 9 1918                              2.313    1.959
     NO 1 1934                                   1.571    1.217
     B 161 1955                                  3.734    3.380
     C 161 1955                                  3.508    3.154


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 8729868                         PUBLICATION DATE:  02/05/2004
Name:       PENSACOLA, NAVAL AIR STATION                      
            FL
NOAA Chart: 11382                           Latitude:   30° 20.7' N (  30.34500)
USGS Quad:  FORT BARRANCAS                  Longitude:  87° 16.4' W ( -87.27330)


                             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.