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Bench Mark Sheet for 9751768, Dorothea Bay, Saint Thomas VI

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


To reach the tidal bench marks from the Cyril E. King Airport on St. Thomas,
exit the airport and turn right onto the Moravian Highway Route 30 and travel
east for 0.6 km (0.4 mi), then turn left on Crown Mountain Road Route 33 and
travel 1.1 km (0.7 mi) north, then turn right on Scott Free Road winding
northward for 1.9 km (1.2 mi) to Route 40, turn left onto Theodore Boschulte
Drive Route 40 traveling NW for 0.1km (0.06 mi) to a large intersection, take a
slight left onto the western most road Route 33 Lionel Pierre Berry Scenic
Drive, continue generally NW for 2.0 km (1.25 mi), then turn right onto Route
333 a poorly marked road heading north and downhill for 0.9 km (0.5 mi) to a
three way fork in the road, continue downhill 1.0 km (0.6 mi) on the center
unmarked unnamed road that is slightly to the left to a turn around and un-gated
private driveway to a condo complex, continue on the driveway that circles the
complex to the west for 0.13 km (0.1 mi) to the end of the road, then travel by
foot on a horse trail that starts just west of the last parking area and winds
up the hill to the west 0.5 km (0.3 mi) north to the end of Ruy Point and the
bench marks are in the bedrock surrounding the end of the point.


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


                 PRIMARY BENCH MARK STAMPING:  1768 A 2010
                         DESIGNATION:          975 1768 A

MONUMENTATION:           Tidal Station disk                    VM#:        19767
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock Outcrop                       OPUS PID:        
LATITUDE:   18° 22.3' N (  18.37136)          LONGITUDE:  64° 57.8' W ( -64.96367)


The primary bench mark is set flush in bedrock on the eastern side of the end of
Ruy Point just north of a large diagonal sheet of volcanic bedrock that runs
from the tree line down to the water, 21.72 m (71.2 ft) SE of bench mark 975
1768 B, 14.85 m (48.7 ft) slope distance east of the center of the footpath
where it emerges from the tree line,  12.59 m (41.3 ft) west of a blunt pinnacle
rock surrounded by red bedrock at the water line, 12.10 m (39.7 ft) slope
distance east from the grass line, and 0.55 m (1.8 ft) above the surrounding
bedrock  that flattens out as it approaches the water.  

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


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


                         BENCH MARK STAMPING:  1768 B 2010
                         DESIGNATION:          975 1768 B

MONUMENTATION:           Tidal Station disk                    VM#:        19768
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock Outcrop                       OPUS PID:        
LATITUDE:   18° 22.3' N (  18.37144)          LONGITUDE:  64° 57.8' W ( -64.96333)


The bench mark is set flush in bedrock on the eastern side of the largest and
most eastern of three bedrock points that extend north into the water from the
end of Ruy Point, 21.72 m (71.2 ft) NW of bench mark 975 1768 A, 15.31 m (50.2
ft) SE of bench mark 975 1768 C, 9.37 m (30.7 ft) west of the southern of two
jointed bedrock pinnacle points at the water line, 8.16 m (26.8 ft) slope
distance NE down from the grass line at the beginning of this bedrock point, 
5.96 m (19.6 ft) slope distance east of the ridge of this bedrock point. 



                         BENCH MARK STAMPING:  1768 C 2010
                         DESIGNATION:          975 1768 C

MONUMENTATION:           Tidal Station disk                    VM#:        19769
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock Outcrop                       OPUS PID#: BBCJ02
LATITUDE:   18° 22.3' N (  18.37153)          LONGITUDE:  64° 57.8' W ( -64.96342)


The bench mark is set flush in bedrock on the largest and most eastern of three
bedrock points extending north into the water from the end of Ruy Point, 41.65 m
(136.6 ft) sloped north of the center of the footpath at the tree line, 30.17 m
(99.0 ft) NE of bench mark 975 1768 D, 19.25 m (63.15 ft) slope distance north
of the grass line at the top of the bluff, 15.77 m (51.7 ft) NW of the southern
of two jointed bedrock pinnacle points at the water line on the east side of Ruy
Point, 15.31 m (50.2 ft) NW of bench mark 975 1768 C, 2.77 m (9.08 ft) north of
the end of the primary ridge of the bedrock point.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


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


                         BENCH MARK STAMPING:  1768 D 2010
                         DESIGNATION:          975 1768 D

MONUMENTATION:           Tidal Station disk                    VM#:        19770
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock Outcrop                       OPUS PID:        
LATITUDE:   18° 22.3' N (  18.37136)          LONGITUDE:  64° 57.8' W ( -64.96367)


The bench mark is set flush in bedrock on the western side of the base of the
center of three bedrock points extending north into the water from the end of
Ruy Point, 30.17 m (99.0 ft) SW of bench mark 975 1768 C, 14.56 m (47.8 ft)
south of the northern end of the center bedrock point, 5.14 m (16.9 ft) slope
distance north of the grass line at the top of this bedrock point, 2.83 m (9.3
ft) slope distance west of the ridgeline of the center bedrock point, 0.86 m
(2.8 ft) east of the eastern edge of a small, coral and stone beach in between
the western and center bedrock points, and 1.14 m (3.7 ft) above the level of
the beach.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


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


                         BENCH MARK STAMPING:  1768 E 2010
                         DESIGNATION:          975 1768 E

MONUMENTATION:           Tidal Station disk                    VM#:        19771
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock Outcrop                       OPUS PID:        
LATITUDE:   18° 22.3' N (  18.37125)          LONGITUDE:  64° 57.8' W ( -64.96378)


The bench mark is set flush in bedrock in the middle of the western most of
three bedrock points that extend north into the water from Ruy Point, 19.25 m
(63.2 ft) NE of the northern edge of a large stone beach that is oriented
north-south turning to the west and to sand on the southern end, 18.02 m (64.4
ft) SW of bench mark 975 1768 D, 10.45 m (34.28 ft) slope distance north of the
tree line, 3.31 m (10.8 ft) west of the small coral and stone beach separating
the western and center bedrock points, 1.61 m (5.3 ft) above the level of the
small coral and stone beach.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


                            T I D A L   D A T U M S 


Tidal datums at RUY POINT, ST THOMAS based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           December 2010 - March 2011
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9755371 SAN JUAN, LA PUNTILLA, SAN JUAN BAY


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.393
     MEAN HIGH WATER                            MHW    =  0.318
     MEAN SEA LEVEL                             MSL    =  0.177
     MEAN TIDE LEVEL                            MTL    =  0.176
     MEAN LOW WATER                             MLW    =  0.034
     MEAN LOWER LOW WATER                       MLLW   =  0.000



Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1768 A 2010                                 4.804    4.486
     1768 B 2010                                 5.348    5.030
     1768 C 2010                                 2.580    2.262
     1768 D 2010                                 2.506    2.188
     1768 E 2010                                 2.458    2.140


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

                                                                                
Station ID: 9751768                         PUBLICATION DATE:  11/18/2011
Name:       RUY POINT, ST THOMAS                              
            VI
NOAA Chart: 25641                           Latitude:   18° 22.3' N (  18.37125)
USGS Quad:  CENTRAL ST THOMAS               Longitude:  64° 57.8' W ( -64.96347)


                             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 defined island datum (VIVD09).  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.

Virgin Islands Vertical Datum of 2009 (VIVD09) is a fixed datum derived from
a simultaneous, least squares, minimum constraint adjustment of leveling
observations.  Local mean sea level relative to the 1983-2001 National Tidal
Datum Epoch observed at tide stations 9751401 located at Lime Tree Bay,
St. Croix, 9751381 located at Lameshur Bay, St. John, and 9751639 located at
Charlotte Amalie, St Thomas was held fixed as the single initial constraint.
VIVD09 replaces all previous height system as the national standard geodetic
reference for heights in the Virgin Islands.  Bench mark elevations relative
to VIVD09 are available from NGS through the World Wide Web at 
National Geodetic Survey.

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 VIVD09 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have VIVD09 elevations.
The VIVD09 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, VIVD09 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from VIVD09 elevations listed for
each bench mark in the NGS database.

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Products available at 9751768 Dorothea Bay, Saint Thomas, VI

Revised: 08/08/2018
NOAA / National Ocean Service
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