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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


To reach the tidal bench marks from the post office at the intersection of 1st
Avenue North and 4th Street in St Petersburg, proceed west on 1st Avenue North
for 4.0 km (2.5 mi) to 34th Street (U.S. Highway 19), then south on U.S. Highway
19 for 5.8 km (3.6 mi) to Pinellas Bayway, then west on Pinellas Bayway for 3.7
km (2.3 mi), continue south on Pinellas Bayway for 10.6 km (6.6 mi) to Anderson
Boulevard, go SW on Anderson Boulevard for 1.69 km (l.05 mi) to old Fort DeSoto,
then 0.6 km (0.4 mi) south along a paved road that leads to the parking area and
fishing pier at the old fort.  The bench marks are in the area between the fort
and the fishing pier.  The tide gage and staff were on the fishing pier.


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


                 PRIMARY BENCH MARK STAMPING:  6364 A 1976
                         DESIGNATION:          872 6364 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        11302
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AG0290
SETTING CLASSIFICATION:  Concrete culvert                      OPUS PID:        
LATITUDE:   27° 36.9' N (  27.61500)          LONGITUDE:  82° 43.8' W ( -82.73000)


The primary bench mark is a disk set in the top of a concrete culvert in Fort
Desoto Park between pier 1 and pier 2, 70 m (231 ft) north of the shoreline, 9 m
(29 ft) east of the centerline of the asphalt road, and 3.11 m (10.2 ft) NW of
the SE end of the culvert.

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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


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


                         BENCH MARK STAMPING:  10 1957
                         DESIGNATION:          872 6364 TIDAL 10
                         ALIAS:                TIDAL 10 STA III 34

MONUMENTATION:           Tidal Station disk                    VM#:        11300
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG5204
SETTING CLASSIFICATION:  Concrete base                         OPUS PID:        
LATITUDE:   27° 36.9' N (  27.61500)          LONGITUDE:  82° 44.2' W ( -82.73670)


The bench mark is a disk set in the top of the NE corner of a 1.83 m (6.0 ft)
square concrete and shell base for a partially destroyed 12 m (40 ft) high
observation tower, about 0.4 km (0.3 mi) SW of Fort Desoto, 89 m (291 ft) SE of
the SE corner of the fishing pier, 32.09 m (105.3 ft) NE of a sea wall, and 1 m
(3 ft) above ground level.

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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


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


                         BENCH MARK STAMPING:  12 1957
                         DESIGNATION:          872 6364 TIDAL 12
                         ALIAS:                TIDAL 12 STA III 34

MONUMENTATION:           Tidal Station disk                    VM#:        11301
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AG5203
SETTING CLASSIFICATION:  Concrete platform                     OPUS PID:        
LATITUDE:   27° 36.8' N (  27.61330)          LONGITUDE:  82° 44.2' W ( -82.73670)


The bench mark is a disk set in the top of the SE corner of a 5 x 4 x 1 m (16 x
12 x 2 ft) high concrete platform, 180 m (592 ft) east of Bench Mark 10 1957,
122 m (400 ft) north of the shoreline, 46 m (150 ft) west of the centerline of
the brick pavement, and 30 m (100 ft) north of the projected centerline of the
east-west brick pavement.



                         BENCH MARK STAMPING:  6364 B 1990
                         DESIGNATION:          872 6364 B TIDAL

MONUMENTATION:           Flange-encased Rod                    VM#:        11303
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AG9426
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AG9426
LATITUDE:   27° 37.0' N (  27.61670)          LONGITUDE:  82° 43.6' W ( -82.72670)


The bench mark is a flange-encased rod located near the west end of the sign for
the fishing pier, 73 m (240 ft) NE of the east edge of the south entrance to the
pier parking lot, 22.10 m (72.5 ft) SE of a paved road, 19.23 m (63.1 ft) north
of the north edge of the parking lot, and 1.28 m (4.2 ft) NW of the SW corner of
the fishing pier sign. The datum point is the top of a stainless steel rod
driven 18.3 m (60 ft) to refusal, and encased in 5-inch logo cap.

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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          PINELLAS
                         ALIAS:                872 6364 TIDAL

MONUMENTATION:           Survey disk                           VM#:        11304
AGENCY:                  Pinellas County                       IDB PID#:  AG9428
SETTING CLASSIFICATION:  Sea wall                              OPUS PID:        
LATITUDE:   27° 36.9' N (  27.61500)          LONGITUDE:  82° 43.6' W ( -82.72670)


The bench mark is a disk set in the surface of the concrete sea wall on the NE
side of the fishing pier, 83 m (272 ft) NW of the concession building, 57 m (186
ft) east of the rest room building, 52 m (169 ft) SE of the SE edge of the paved
parking lot, 5 m (15 ft) NE of the NE side of the concrete pier, and 1 m (3 ft)
below pier level.

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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


                            T I D A L   D A T U M S 


Tidal datums at MULLET KEY, TAMPA BAY based on:

     LENGTH OF SERIES:      2 Years
     TIME PERIOD:           June 1990 - May 1991
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8726520 ST. PETERSBURG, TAMPA BAY


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

     HIGHEST OBSERVED WATER LEVEL (12/03/1990)         =  1.041
     MEAN HIGHER HIGH WATER                     MHHW   =  0.634
     MEAN HIGH WATER                            MHW    =  0.556
     North American Vertical Datum              NAVD88 =  0.464
     MEAN SEA LEVEL                             MSL    =  0.338
     MEAN TIDE LEVEL                            MTL    =  0.331
     MEAN LOW WATER                             MLW    =  0.106
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/19/1977)         = -0.659

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     6364 A 1976                                 1.417    0.861
     10 1957                                     2.088    1.532
     12 1957                                     2.742    2.186
     6364 B 1990                                 1.276    0.720
     PINELLAS                                    2.283    1.727


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

                                                                                
Station ID: 8726364                         PUBLICATION DATE:  04/21/2003
Name:       MULLET KEY, TAMPA BAY                             
            FL
NOAA Chart: 11414                           Latitude:   27° 36.9' N (  27.61500)
USGS Quad:  ANNA MARIA                      Longitude:  82° 43.6' W ( -82.72670)


                             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.