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

                                                                                
Station ID: 8722621                         PUBLICATION DATE:  03/08/2009
Name:       PALM BEACH, BRAZILIAN DOCK,                       
            FL
NOAA Chart: 11466                           Latitude:   26° 42.3' N (  26.70500)
USGS Quad:  PALM BEACH                      Longitude:  80°  2.7' W ( -80.04500)


To reach the tidal bench marks from the east end of the Royal Palm Bridge
(center of three bridges to Palm Beach) proceed 0.80 km (0.5 mi) east on Royal
Palm Way to the junction of Lake Drive, then 0.16 km (0.1 mi) south on Lake
Drive to the junction of Brazilian Avenue and the entrance to Brazilian Dock. 
The bench marks are in the area between Royal Palm Way and Brazilian Dock.  The
tide gage and staff were located on the dock.


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


                 PRIMARY BENCH MARK STAMPING:  A 2621 1976
                         DESIGNATION:          872 2621 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5603
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD5809
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   26° 42.3' N (  26.70500)          LONGITUDE:  80°  2.7' W ( -80.04500)


The primary bench mark is a disk set in a concrete retaining wall along the east
bank of the Intracoastal Waterway, 128.90 m (422.9 ft) south of the highway
centerline, 40.69 m (133.5 ft) south of bench mark A 2621 1976, 9.39 m (30.8 ft)
north of the NE corner of the Brazilian dock masters office, and 6.19 m (20.3
ft) east of and level with the center of a paved path.  

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

                                                                                
Station ID: 8722621                         PUBLICATION DATE:  03/08/2009
Name:       PALM BEACH, BRAZILIAN DOCK,                       
            FL
NOAA Chart: 11466                           Latitude:   26° 42.3' N (  26.70500)
USGS Quad:  PALM BEACH                      Longitude:  80°  2.7' W ( -80.04500)


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


                         BENCH MARK STAMPING:  E 233 1965
                         DESIGNATION:          E 233

MONUMENTATION:           Bench Mark disk                       VM#:         5602
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AD2823
SETTING CLASSIFICATION:  Concrete abutment                     OPUS PID:        
LATITUDE:   26° 42.3' N (  26.70500)          LONGITUDE:  80°  2.6' W ( -80.04330)


The bench mark is a disk set flush on the top center of the SE concrete abutment
of Royal Palm Bridge, 9.60 m (31.5 ft) south of the centerline of the bridge,
2.23 m (7.3 ft) west of the east end of the SE abutment, and 1.01 m (3.3 ft)
above the sidewalk.



                         BENCH MARK STAMPING:  B 2621 1976
                         DESIGNATION:          872 2621 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5604
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD5808
SETTING CLASSIFICATION:  Concrete Retaining Wall               OPUS PID:        
LATITUDE:   26° 42.3' N (  26.70500)          LONGITUDE:  80°  2.7' W ( -80.04500)


The bench mark is a disk set in a concrete retaining wall along the east bank of
the Intracoastal Waterway, 88.21 m (289.4 ft) south of the highway centerline,
45.29 m (148.6 ft) south of bench mark C 26211976, 40.69 m (133.5 ft) north of
bench mark A 2621 1976, and 6.19 m (20.3 ft) east of and level with the center
of a paved path.

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

                                                                                
Station ID: 8722621                         PUBLICATION DATE:  03/08/2009
Name:       PALM BEACH, BRAZILIAN DOCK,                       
            FL
NOAA Chart: 11466                           Latitude:   26° 42.3' N (  26.70500)
USGS Quad:  PALM BEACH                      Longitude:  80°  2.7' W ( -80.04500)


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


                         BENCH MARK STAMPING:  C 2621 1976
                         DESIGNATION:          872 2621 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5605
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD5807
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   26° 42.3' N (  26.70500)          LONGITUDE:  80°  2.7' W ( -80.04500)


The bench mark is a disk set in a concrete retaining wall along the east bank of
the Intracoastal Waterway, 45.29 m (148.6 ft) north of bench mark B 2621 1976,
42.89 m (140.7 ft) south of the highway centerline, 33.31 m (109.3 ft) south of
bench mark E 233 1965, and 6.19 m (20.3 ft) west of and level with the center of
a paved path.



                         BENCH MARK STAMPING:  E2621 1976
                         DESIGNATION:          872 2621 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5606
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AD5806
SETTING CLASSIFICATION:  Concrete abutment                     OPUS PID:        
LATITUDE:   26° 42.4' N (  26.70670)          LONGITUDE:  80°  2.7' W ( -80.04500)


The bench mark is a disk set flush on the top center of the NE concrete abutment
of Royal Palm Bridge, 9.60 m (31.5 ft)  north of the centerline of the bridge,
2.26 m (7.4 ft) west of the east end of the NE abutment, and 1.01 m (3.3 ft)
above the sidewalk.

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

                                                                                
Station ID: 8722621                         PUBLICATION DATE:  03/08/2009
Name:       PALM BEACH, BRAZILIAN DOCK,                       
            FL
NOAA Chart: 11466                           Latitude:   26° 42.3' N (  26.70500)
USGS Quad:  PALM BEACH                      Longitude:  80°  2.7' W ( -80.04500)


                            T I D A L   D A T U M S 


Tidal datums at PALM BEACH, BRAZILIAN DOCK, based on:

     LENGTH OF SERIES:      10 YEARS
     TIME PERIOD:           January 1977 - December 1986
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8724580 KEY WEST


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

     HIGHEST OBSERVED WATER LEVEL (11/23/1984)         =  1.531
     MEAN HIGHER HIGH WATER                     MHHW   =  0.887
     MEAN HIGH WATER                            MHW    =  0.830
     North American Vertical Datum              NAVD88 =  0.735
     MEAN TIDE LEVEL                            MTL    =  0.439
     MEAN SEA LEVEL                             MSL    =  0.431
     MEAN LOW WATER                             MLW    =  0.047
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (03/18/1980)         = -0.380

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     A 2621 1976                                 1.718    0.888
     E 233 1965                                  4.523    3.693
     B 2621 1976                                 1.717    0.887
     C 2621 1976                                 1.705    0.875
     E2621 1976                                  4.528    3.698


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

                                                                                
Station ID: 8722621                         PUBLICATION DATE:  03/08/2009
Name:       PALM BEACH, BRAZILIAN DOCK,                       
            FL
NOAA Chart: 11466                           Latitude:   26° 42.3' N (  26.70500)
USGS Quad:  PALM BEACH                      Longitude:  80°  2.7' W ( -80.04500)


                             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.