U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  4

                                                   PUBLICATION DATE:  12/16/1991
Station ID: 8722706                                SUPERCEDED DATE:   04/21/2003
Name:       BOYNTON BEACH, LAKE WORTH                         
            FLORIDA
NOAA Chart: 11466                                  Latitude:         26° 32.9' N
USGS Quad:  LAKE WORTH                             Longitude:        80°  3.2' W


To reach the tidal bench marks from the junction of State Highway 804 (NE 2nd
Avenue) with U.S. Highway 1 in Boynton Beach, proceed north on U.S. Highway 1
for 1.4 miles (2.3 km) to the entrance to Shooters Restaurant located at 2280
North Federal Highway, continue east on the paved drive for 0.1 mile (0.2 km) to
the restaurant.  The bench marks are on the bulkhead, north of the restaurant,
and across U.S. Highway 1 at the entrance.  The tide gauge and staff were on the
north side of the restaurant boat basin.


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


                 PRIMARY BENCH MARK STAMPING:  U 233 1965

MONUMENTATION:           Survey Disk                               VM#:     7453
AGENCY:                                                            PID#:  AD2743
SETTING CLASSIFICATION:  Concrete Monument


The primary bench mark is set in the top of a concrete monument across U.S.
Highway 1 from the entrance to Shooters Restaurant, 0.2 mile (0.3 km) north of
mile post 311, 186.0 feet (56.7 m) south of a road crossing, 22.9 feet (7.0 m)
west of the west rail of the railroad tracks, 3.0 feet (0.9 m) south of the
first power pole south of the crossing, 1.5 feet (0.5 m) north of a witness
post, and level with the rail.



                         BENCH MARK STAMPING:  2706 F 1986

MONUMENTATION:           Survey Disk                               VM#:     7454
AGENCY:                                                            PID#:  AD8076
SETTING CLASSIFICATION:  Concrete Sea Wall


The bench mark is set in the top of the north end of a concrete sea wall just to
the north of the boat basin at Shooters Restaurant, at the east end of Las
Palmas Avenue, and 115 feet (35 m) north of the extended centerline of Las
Palmas Avenue and a wooden dock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  4

                                                   PUBLICATION DATE:  12/16/1991
Station ID: 8722706                                SUPERCEDED DATE:   04/21/2003
Name:       BOYNTON BEACH, LAKE WORTH                         
            FLORIDA
NOAA Chart: 11466                                  Latitude:         26° 32.9' N
USGS Quad:  LAKE WORTH                             Longitude:        80°  3.2' W


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


                         BENCH MARK STAMPING:  2706 G 1986

MONUMENTATION:           Survey Disk                               VM#:     7455
AGENCY:                                                            PID#:  AD8077
SETTING CLASSIFICATION:  Concrete Sea Wall


The bench mark is set in the top of and near the center of a concrete sea wall
just to the north of the boat basin at Shooters Restaurant, 110 feet (34 m)
south of the north end of the sea wall, 100 feet (30 m) east of the end of Las
Palmas Avenue, and 4 feet (1 m) north of the centerline of a wooden dock.



                         BENCH MARK STAMPING:  2706 H 1986

MONUMENTATION:           Survey Disk                               VM#:     7456
AGENCY:                                                            PID#:  AD8078
SETTING CLASSIFICATION:  Concrete Sea Wall


The bench mark is set in the top of the south end of a concrete sea wall just to
the north of the boat basin at Shooters Restaurant, 110 feet (34 m) south of the
centerline of a wooden dock.



                         BENCH MARK STAMPING:  2706 J 1986

MONUMENTATION:           Survey Disk                               VM#:     7457
AGENCY:                                                            PID#:  AD8075
SETTING CLASSIFICATION:  Concrete Storm Drain


The bench mark is set in the top of a concrete drain 275 feet   (84 m) south of
the centerline of Las Palmas Avenue, 72.5 feet (22.1 m) south of the centerline
of the south entrance drive to Shooters Restaurant and 12 feet (4 m) north of
powerline pole #6-8111-7019-0-5.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  4

                                                   PUBLICATION DATE:  12/16/1991
Station ID: 8722706                                SUPERCEDED DATE:   04/21/2003
Name:       BOYNTON BEACH, LAKE WORTH                         
            FLORIDA
NOAA Chart: 11466                                  Latitude:         26° 32.9' N
USGS Quad:  LAKE WORTH                             Longitude:        80°  3.2' W


                            T I D A L   D A T U M S 


Tidal datums at BOYNTON BEACH, LAKE WORTH based on:

     LENGTH OF SERIES:      40 MONTHS
     TIME PERIOD:           MAY 1970 - OCTOBER 1973
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  8723170 MIAMI BEACH


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

     HIGHEST OBSERVED WATER LEVEL (10/25/1973)         =   4.86
     MEAN HIGHER HIGH WATER                     MHHW   =   2.86
     MEAN HIGH WATER                            MHW    =   2.69
     MEAN TIDE LEVEL                            MTL    =   1.43
   * NATIONAL GEODETIC VERTICAL DATUM           NGVD29 =   0.95
     MEAN LOW WATER                             MLW    =   0.16
     MEAN LOWER LOW WATER                       MLLW   =   0.00
     LOWEST  OBSERVED WATER LEVEL (04/24/1970)         =  -0.81

   * NGVD is based on elevations published in Quad 260801, 2/72 and NOS leveling
     of 1981. 
North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In FEET above:

     Stamping or Designation                    MLLW        MHW

     U 233 1965                                 12.35      9.66
     2706 F 1986                                 6.21      3.52
     2706 G 1986                                 6.21      3.52
     2706 H 1986                                 6.18      3.49
     2706 J 1986                                11.04      8.35


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

                                                   PUBLICATION DATE:  12/16/1991
Station ID: 8722706                                SUPERCEDED DATE:   04/21/2003
Name:       BOYNTON BEACH, LAKE WORTH                         
            FLORIDA
NOAA Chart: 11466                                  Latitude:         26° 32.9' N
USGS Quad:  LAKE WORTH                             Longitude:        80°  3.2' W


                             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 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.