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

                                                   PUBLICATION DATE:  11/09/1990
Station ID: 9751540                                SUPERCEDED DATE:   04/21/2003
Name:       ST THOMAS, RED HOOK BAY                           
            VIRGIN ISLANDS
NOAA Chart: 25647                                  Latitude:         18° 19.5' N
USGS Quad:  EASTERN ST THOMAS                      Longitude:        64° 51.0' W


To reach the tidal bench marks from the intersection of Mafolic Road and Sugar
Estate Road (Route 38) in downtown Charlotte Amalie, proceed east on Route 38
(turns into Weymouth Reymer Highway) for 3 miles (5 km) to Turpentine Run Road
(Route 32), then SE on Route 32 for 1 mile (2 km) to Redhook Road (Route 32),
then east on Redhook Road for 1.5 miles (2.4 km) to the entrance to National
Park Service (NPS) Redhook Bay Park, continue into the park for 0.5 mile    (0.8
km) to NPS Redhook Bay Visitors Station.  The bench marks are near the visitors
station.  The tide gage and staff were on the NPS pier.


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


                 PRIMARY BENCH MARK STAMPING:  NO 1 1973

MONUMENTATION:           Survey Disk                               VM#:     7933
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Foundation


The bench mark is set flush in the center of the concrete foundation of the NPS
antenna tower, 21.7 feet (6.6 m) west of the SW corner of the NPS Visitors
Station building.



                         BENCH MARK STAMPING:  NO 2 1973

MONUMENTATION:           Survey Disk                               VM#:     7934
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Foundation


The bench mark is set flush in the concrete foundation on the south side of the
NPS Visitors Station building, 37 feet (11 m) east of the south entrance to the
building.

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

                                                   PUBLICATION DATE:  11/09/1990
Station ID: 9751540                                SUPERCEDED DATE:   04/21/2003
Name:       ST THOMAS, RED HOOK BAY                           
            VIRGIN ISLANDS
NOAA Chart: 25647                                  Latitude:         18° 19.5' N
USGS Quad:  EASTERN ST THOMAS                      Longitude:        64° 51.0' W


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


                         BENCH MARK STAMPING:  NO 3 1973

MONUMENTATION:           Survey Disk                               VM#:     7935
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Footing


The bench mark is set flush in the concrete footing on the NW corner of the NPS
headquarters office building, 34 feet (10 m) from the entrance to the building.



                         BENCH MARK STAMPING:  USDI 1 ELEV 2.82 NPS

MONUMENTATION:           Survey Disk                               VM#:     7936
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Foundation


The bench mark is set flush in the NE corner of the concrete bulkhead
foundation, 39 feet (12 m) NE of the NE corner of the NPS Visitors Station
building, and 1 foot (0.3 m) SW of the NE corner.



                         BENCH MARK STAMPING:  USDI 2 ELEV 2.85 NPS

MONUMENTATION:           Survey Disk                               VM#:     7937
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Foundation


The bench mark is set flush in the concrete bulkhead foundation, 35.5 feet  
(10.8 m) NE of the NW bulkhead corner, and 4 feet (1 m) SW of the foot of the
pier.

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

                                                   PUBLICATION DATE:  11/09/1990
Station ID: 9751540                                SUPERCEDED DATE:   04/21/2003
Name:       ST THOMAS, RED HOOK BAY                           
            VIRGIN ISLANDS
NOAA Chart: 25647                                  Latitude:         18° 19.5' N
USGS Quad:  EASTERN ST THOMAS                      Longitude:        64° 51.0' W


                            T I D A L   D A T U M S 


Tidal datums at ST THOMAS, RED HOOK BAY based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           FEBRUARY-MARCH 1975
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  9751639 CHARLOTTE AMALIE


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

     HIGHEST OBSERVED WATER LEVEL (11/12/1973)         =   1.82
     MEAN HIGHER HIGH WATER                     MHHW   =   1.14
     MEAN HIGH WATER                            MHW    =   0.97
     MEAN TIDE LEVEL                            MTL    =   0.56
     MEAN LOW WATER                             MLW    =   0.15
     MEAN LOWER LOW WATER                       MLLW   =   0.00
     LOWEST  OBSERVED WATER LEVEL (02/04/1975)         =  -0.32



Bench Mark Elevation Information                In FEET above:

     Stamping or Designation                    MLLW        MHW

     NO 1 1973                                   3.55      2.58
     NO 2 1973                                   3.36      2.39
     NO 3 1973                                   7.63      6.66
     USDI 1 ELEV 2.82 NPS                        3.08      2.11
     USDI 2 ELEV 2.85 NPS                        3.10      2.13


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

                                                   PUBLICATION DATE:  11/09/1990
Station ID: 9751540                                SUPERCEDED DATE:   04/21/2003
Name:       ST THOMAS, RED HOOK BAY                           
            VIRGIN ISLANDS
NOAA Chart: 25647                                  Latitude:         18° 19.5' N
USGS Quad:  EASTERN ST THOMAS                      Longitude:        64° 51.0' 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 any other fixed island datum.

This tide station location has a local island datum.  Island datums
are specific fixed geodetic datums whose elevation relationship 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.