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Bench Mark Sheet for 8455083, POINT JUDITH, HARBOR OF REFUGE RI

Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8455083                         PUBLICATION DATE:  04/01/2004
Name:       POINT JUDITH, HARBOR OF REFUGE                    
            RI
NOAA Chart: 13219                           Latitude:   41° 21.8' N (  41.36330)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 29.4' W ( -71.49000)


To reach the tidal bench marks from the intersection of State Highway 108 and
Ocean Road in Point Judith, proceed 0.8 km (0.5 mi) south on Ocean Road, then
bear right at a turn in the road and continue to the entrance of Breakwater
Village, then turn left on a dirt drive after passing through the entrance gate
and continue down the hill, through the trailer park, to the small boat basin. 
The bench marks are located in the vicinity of the boat basin and the eastern
breakwater of the Harbor of Refuge.  The tide gage is located at the SW corner
of a breakwater on the east side of the small boat basin.  The tide staff is
located on a cluster of pilings just inside the mouth of the basin on the east
side.


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


                 PRIMARY BENCH MARK STAMPING:  5083 D 1987
                         DESIGNATION:          845 5083 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2212
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Granite Boulder                       OPUS PID:        
LATITUDE:   41° 21.8' N (  41.36330)          LONGITUDE:  71° 29.4' W ( -71.49000)


The primary bench mark is a disk set in a large granite boulder on the south
side of a small boat basin at Breakwater Village, 38 m (124 ft) WNW of power
pole #4584, 12 m (41 ft) WSW of a three pile cluster at the SE corner of the
boat basin, 3 m (10 ft) WSW of an abandoned steel pole base filled with
concrete, 2 m (6 ft) SE of the easternmost of four abandoned dock pilings,  0.85
m (2.8 ft) east of the east edge of a wooden walkway leading to a floating dock,
and 0.21m ( 0.7 ft) above the walkway.

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

                                                                                
Station ID: 8455083                         PUBLICATION DATE:  04/01/2004
Name:       POINT JUDITH, HARBOR OF REFUGE                    
            RI
NOAA Chart: 13219                           Latitude:   41° 21.8' N (  41.36330)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 29.4' W ( -71.49000)


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


                         BENCH MARK STAMPING:  NO 7 1948
                         DESIGNATION:          845 5083 TIDAL 7

MONUMENTATION:           Tidal Station disk                    VM#:         2210
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Concrete head wall                    OPUS PID:        
LATITUDE:   41° 21.8' N (  41.36330)          LONGITUDE:  71° 29.4' W ( -71.49000)


The bench mark is a disk set in the south end of a 2 m (6 ft) long concrete
headwall on the west side of an abandoned gun emplacement which is located
between the Point Judith Coast Guard Station and the eastern breakwater of the
Harbor of Refuge, 39 m (128 ft) east of the center of a large rock on the beach,
31 m (101 ft) NW of the center of a concrete manhole structure on the beach,
0.12 m (0.4 ft) north of the south end of the head wall, and 0.61 m (2.0 ft)
above ground level.

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

                                                                                
Station ID: 8455083                         PUBLICATION DATE:  04/01/2004
Name:       POINT JUDITH, HARBOR OF REFUGE                    
            RI
NOAA Chart: 13219                           Latitude:   41° 21.8' N (  41.36330)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 29.4' W ( -71.49000)


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


                         BENCH MARK STAMPING:  5083 E 1989
                         DESIGNATION:          845 5083 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2213
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 21.8' N (  41.36330)          LONGITUDE:  71° 29.4' W ( -71.49000)


The bench mark is disk set along the NE shoulder of the gravel parking lot of
the Camp Cronin Fishing Area off of Ocean Road, in line with the east face of
the eastern breakwater of the Harbor of Refuge, 122 m (400 ft) NW of bench mark
NO 7 1948, 56 m (185 ft) SE of the northernmost boulder of the group of boulders
at the NW edge of the parking lot, 52 m (170 ft) NE of the shore end of the
eastern breakwater, and 2.56 m( 8.4 ft) NE of the approximate edge of the
parking lot.  The bench mark is set 0.61 (2.0 ft) below the level of the parking
lot, crimped to the top of a stainless steel rod driven 12.2 m (40 ft) to
refusal and encased in a PVC pipe.



                         BENCH MARK STAMPING:  5083 F 1989
                         DESIGNATION:          84505083 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2214
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete manhole                      OPUS PID:        
LATITUDE:   41° 21.8' N (  41.36330)          LONGITUDE:  71° 29.4' W ( -71.49000)


The bench mark is a disk set in the north corner of a concrete manhole at the NE
side of an abandoned gun emplacement located between the Point Judith Coast
Guard Station and the eastern breakwater of the Harbor or Refuge, 7.99 m (26.2
ft) SE of the center of the gravel road leading to the Camp Cronin Fishing Area,
1.04 m (3.4 ft) NW of the east corner of the manhole, and 0.30 m (1.0 ft) south
of a NOS witness post.

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

                                                                                
Station ID: 8455083                         PUBLICATION DATE:  04/01/2004
Name:       POINT JUDITH, HARBOR OF REFUGE                    
            RI
NOAA Chart: 13219                           Latitude:   41° 21.8' N (  41.36330)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 29.4' W ( -71.49000)


                            T I D A L   D A T U M S 


Tidal datums at POINT JUDITH, HARBOR OF REFUGE based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           August 1987 - October 1987
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8452660 NEWPORT, NARRAGANSETT BAY


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.030
     MEAN HIGH WATER                            MHW    =  0.953
     MEAN TIDE LEVEL                            MTL    =  0.496
     MEAN SEA LEVEL                             MSL    =  0.468
     MEAN LOW WATER                             MLW    =  0.038
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5083 D 1987                                 2.029    1.076
     NO 7 1948                                   5.273    4.320
     5083 E 1989                                 4.310    3.357
     5083 F 1989                                 5.881    4.928


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

                                                                                
Station ID: 8455083                         PUBLICATION DATE:  04/01/2004
Name:       POINT JUDITH, HARBOR OF REFUGE                    
            RI
NOAA Chart: 13219                           Latitude:   41° 21.8' N (  41.36330)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 29.4' W ( -71.49000)


                             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.

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Products available at 8455083 POINT JUDITH, HARBOR OF REFUGE, RI

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services