U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8721374                         PUBLICATION DATE:  06/08/2009
Name:       ALLENHURST,HAULOVER CANAL                         
            FL
NOAA Chart: 11484                           Latitude:   28° 44.0' N (  28.73330)
USGS Quad:  MIMS                            Longitude:  80° 45.4' W ( -80.75670)


To reach the tidal bench marks from the intersection of U.S. Highway 1 and State
Road 402 in Titusville, proceed east on State Road 402 for about 13 km (8 mi) to
State Road 3, then north on State Road 3 for 2.29 m (7.5 mi) to the drawbridge
over the Intracoastal Waterway.  The bench marks are in the area around the
bridge.  The tide gage and staff were on the bridge fender.


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


                 PRIMARY BENCH MARK STAMPING:  IWBV USE 106
                         DESIGNATION:          872 1374 MBV USE 106

MONUMENTATION:           Survey disk                           VM#:         5327
AGENCY:                  US Army Corps Of Engineers (USE)      IDB PID#:  AK0721
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID#: AK0721
LATITUDE:   28° 44.2' N (  28.73670)          LONGITUDE:  80° 45.3' W ( -80.75500)


The bench mark is a disk set in the top of a concrete monument, SW of the Bridge
over Haulover Canal, 15 m (49 ft) SW of the centerline of the old highway, 6 m
(19 ft) NW of the centerline of a sand road leading SW, and about level with the
old highway.



                         BENCH MARK STAMPING:  NO 3 1941
                         DESIGNATION:          872 1374 TIDAL 3

MONUMENTATION:           Survey disk                           VM#:         5322
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AK0718
SETTING CLASSIFICATION:  Set in drill hole near step           OPUS PID:        
LATITUDE:   28° 44.2' N (  28.73670)          LONGITUDE:  80° 45.3' W ( -80.75500)


The bench mark is a disk set in a drill hole near the north end of the third
concrete step from the bottom of the remaining steps of the destroyed Post
Office and General Store, NW of the bridge over the Haulover Canal, and 10 m (32
ft) west of the centerline of the old highway.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8721374                         PUBLICATION DATE:  06/08/2009
Name:       ALLENHURST,HAULOVER CANAL                         
            FL
NOAA Chart: 11484                           Latitude:   28° 44.0' N (  28.73330)
USGS Quad:  MIMS                            Longitude:  80° 45.4' W ( -80.75670)


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


                         BENCH MARK STAMPING:  318 JLR 1962
                         DESIGNATION:          872 1374 318 JLR

MONUMENTATION:           Survey disk                           VM#:         5323
AGENCY:                  US Army Corps Of Engineers (USE)      IDB PID#:  AK0722
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   28° 44.2' N (  28.73670)          LONGITUDE:  80° 45.3' W ( -80.75500)


The primary bench mark is a disk set in the top of a concrete monument 0.3 km
(0.2 mi) south of Bench Mark IWBV 106, 17.53 m (57.5 ft) SE of a cabbage palm,
8.69 m (28.5 ft) west of the centerline of the old highway, midway between two
white witness posts, 0.61 m (2.0 ft) above the level of the highway, and 0.24 m
(0.8 ft) above ground level.



                         BENCH MARK STAMPING:  NO 1 1972
                         DESIGNATION:          872 1374 TIDAL 1

MONUMENTATION:           Survey disk                           VM#:         5324
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AK7010
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   28° 44.2' N (  28.73670)          LONGITUDE:  80° 45.3' W ( -80.75500)


The bench mark is a disk set flush in the NW end of the concrete bulkhead under
the north end of the bridge, 10.49 m (34.4 ft) west of the west side of the
bridge.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8721374                         PUBLICATION DATE:  06/08/2009
Name:       ALLENHURST,HAULOVER CANAL                         
            FL
NOAA Chart: 11484                           Latitude:   28° 44.0' N (  28.73330)
USGS Quad:  MIMS                            Longitude:  80° 45.4' W ( -80.75670)


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


                         BENCH MARK STAMPING:  NO 2 1972
                         DESIGNATION:          872 1374 TIDAL 2

MONUMENTATION:           Survey disk                           VM#:         5325
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AK7012
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   28° 44.2' N (  28.73670)          LONGITUDE:  80° 45.3' W ( -80.75500)


The bench mark is a disk set flush in the SW end of the concrete bulkhead under
the south end of the bridge.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8721374                         PUBLICATION DATE:  06/08/2009
Name:       ALLENHURST,HAULOVER CANAL                         
            FL
NOAA Chart: 11484                           Latitude:   28° 44.0' N (  28.73330)
USGS Quad:  MIMS                            Longitude:  80° 45.4' W ( -80.75670)


                            T I D A L   D A T U M S 


Tidal datums at ALLENHURST,HAULOVER CANAL based on:

     LENGTH OF SERIES:      5 MONTHS
     TIME PERIOD:           December 1982 - April 1983
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8721456 TITUSVILLE, INDIAN RIVER


Elevations of tidal datums referred to Mean Sea Level (MSL), in METERS:

     North American Vertical Datum              NAVD88 =  0.173
     MEAN SEA LEVEL                             MSL    =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                                MSL

     IWBV USE 106                                         2.238
     NO 3 1941                                            2.756
     318 JLR 1962                                         2.427
     NO 1 1972                                            1.301
     NO 2 1972                                            1.306


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

                                                                                
Station ID: 8721374                         PUBLICATION DATE:  06/08/2009
Name:       ALLENHURST,HAULOVER CANAL                         
            FL
NOAA Chart: 11484                           Latitude:   28° 44.0' N (  28.73330)
USGS Quad:  MIMS                            Longitude:  80° 45.4' W ( -80.75670)


                             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.