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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


To reach the tidal bench marks from the junction of State Road 776 (South McCall
Road) and State Road 775 (Placidia Road/Pine Street) in Englewood, proceed west
on State Road 776 for 0.8 km (0.5 mi) to Beach Road, then turn left and proceed
SW to the Tom Adams Bridge.  The bench marks are in the vicinity of the bridge. 
The tide gage and staff were located west of the bridge tender's house.


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


                 PRIMARY BENCH MARK STAMPING:  NO 1 1973
                         DESIGNATION:          872 5747 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         6048
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AG7835
SETTING CLASSIFICATION:  Concrete culvert abutment             OPUS PID:        
LATITUDE:   26° 56.0' N (  26.93330)          LONGITUDE:  82° 21.2' W ( -82.35330)


The primary bench mark is a disk set in the top of a concrete culvert head wall,
59 m (195 ft) south of the south corner of the bridge, 9 m (30 ft) SE of the
center line of the highway, 5 m (18 ft) south of the SW end of the bridge
bulkhead, 3 m (10 ft) SSE of the Tom Adams Bridge Monument, 3 m (10 ft) SE of a
manhole cover, and 0.3 m (1 ft) below the level of the highway.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


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


                         BENCH MARK STAMPING:  IWCH 21 1965
                         DESIGNATION:          IWCH 21

MONUMENTATION:           Survey disk                           VM#:         6047
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  AG7833
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   26° 56.0' N (  26.93397)          LONGITUDE:  82° 21.2' W ( -82.35336)


The bench mark is a disk set flush in the center of the sidewalk between the
bridge guard rail and the concrete sidewalk rail on the SE side of the Tom Adams
Bridge, 32 m (105 ft) SW of the drawbridge span, and 20 m (65 ft) NE of the SW
traffic lift gate.

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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


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


                         BENCH MARK STAMPING:  5747 B
                         DESIGNATION:          872 5747 B TIDAL
                         ALIAS:                FLORIDA SRD (SEAWALL)

MONUMENTATION:           Survey disk                           VM#:         6051
AGENCY:                  Florida Department of Transportation
                         (FLDOT)                               IDB PID#:  AG7830
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   26° 56.1' N (  26.93500)          LONGITUDE:  82° 21.1' W ( -82.35170)


The bench mark is a disk set in the top of a concrete bulkhead at the NE end of
the Tom Adams Bridge, 6 m (20 ft) NW of the north corner of the bridge, 2 m (8
ft) below the bridge deck, and 0.15 m (0.5 ft) from the offshore edge of the
bulkhead.  NOTE: The bench mark is historically known as FLORIDA SRD (SEAWALL).

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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


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


                         BENCH MARK STAMPING:  5747 C
                         DESIGNATION:          872 5747 C TIDAL
                         ALIAS:                FLORIDA SRD (NW)

MONUMENTATION:           Survey disk                           VM#:         6052
AGENCY:                  Florida Department of Transportation
                         (FLDOT)                               IDB PID#:  AG7832
SETTING CLASSIFICATION:  Concrete bridge curb                  OPUS PID:        
LATITUDE:   26° 56.1' N (  26.93500)          LONGITUDE:  82° 21.1' W ( -82.35170)


The bench mark is a disk set flush in the top center of the 0.3 m (1 ft) high
concrete bridge curb supporting a metal guardrail at the NW corner of the Tom
Adams bridge, 4.11 m (13.5 ft) NW of the centerline of the highway, 9 m (30 ft)
south of a concrete power pole, 3 m (10 ft) south of the north end of the
abutment, 1 m (4 ft) SE of the concrete handrail, and 0.3 m (1 ft) SW of the
seam at the NE end where the bridge meets the highway.  NOTE: The bench mark is
historically known as FLORIDA SRD (NW).

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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


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


                         BENCH MARK STAMPING:  5747 D
                         DESIGNATION:          872 5747 D TIDAL
                         ALIAS:                FLORIDA SRD (SW)

MONUMENTATION:           Survey disk                           VM#:         6053
AGENCY:                  Florida Department of Transportation
                         (FLDOT)                               IDB PID#:  AG7834
SETTING CLASSIFICATION:  Concrete walkway curb                 OPUS PID:        
LATITUDE:   26° 56.0' N (  26.93330)          LONGITUDE:  82° 21.2' W ( -82.35330)


The bench mark is a disk set flush in the top center of the SW concrete walkway
curb on the Tom Adams bridge, 3 m (10 ft) NE of the SW bridge abutment, 1 m (4
ft) NW of a concrete handrail, and 0.3 m (1 ft) NE of the seam at the SW end of
the bridge where it meets the highway.  NOTE: The bench mark is historically
known as FLORIDA SRD (SW).

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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


                            T I D A L   D A T U M S 


Tidal datums at ENGLEWOOD, LEMON BAY based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           March 1976 - February 1977
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8725110 NAPLES, GULF OF MEXICO


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

     HIGHEST OBSERVED WATER LEVEL (05/15/1976)         =  0.918
     MEAN HIGHER HIGH WATER                     MHHW   =  0.478
     North American Vertical Datum              NAVD88 =  0.439
     MEAN HIGH WATER                            MHW    =  0.398
     MEAN TIDE LEVEL                            MTL    =  0.246
     MEAN SEA LEVEL                             MSL    =  0.244
     MEAN LOW WATER                             MLW    =  0.093
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/19/1977)         = -0.377

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 1 1973                                   1.665    1.267
     IWCH 21 1965                                7.047    6.649
     5747 B                                      1.341    0.943
     5747 C                                      4.012    3.614
     5747 D                                      3.932    3.534


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

                                                                                
Station ID: 8725747                         PUBLICATION DATE:  02/05/2004
Name:       ENGLEWOOD, LEMON BAY                              
            FL
NOAA Chart: 11425                           Latitude:   26° 56.0' N (  26.93330)
USGS Quad:  ENGLEWOOD                       Longitude:  82° 21.2' W ( -82.35330)


                             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.