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Bench Mark Sheet for 8453742, WEST JAMESTOWN 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


To reach the tidal bench marks from Newport, Rhode Island proceed west across
the Newport Bridge on State Road 138 onto Conanicut Island, turn left (south)
and travel 1.6 km (1 mi) to Narragansett Avenue, turn right (west) onto
Narragansett Avenue and travel 3 km (2 mi) until the road terminates at the
wharf at Dutch Harbor.  The bench marks are located in the vicinity of the
parking area at the wharf.  The tide gage and staff were located on the south
side of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  3742 A 1977
                         DESIGNATION:          845 3742 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2189
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.2' W ( -71.38670)


The primary bench mark is a disk set flush in the concrete slab at the entrance
to the Dutch Harbor Marine Inc. Office, 13 m (42 ft) north of the centerline of
Narragansett Avenue, 1.07 m (3.5 ft) north of the south end of the concrete
slab, and 0.21 m (0.7 ft) west of the front wall of the Office.

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

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


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


                         BENCH MARK STAMPING:  3742 B 1977
                         DESIGNATION:          845 3742 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2190
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.2' W ( -71.38670)


The bench mark is a disk set flush in top of a small curb-like seawall on the
north side of the parking area and west of the Dutch Harbor Marine Inc. Office,
23 m (75 ft) north of the centerline of Narragansett Avenue (extended) 11 m (37
ft) SE of the shoreline at the east end of the seawall (parking lot curb).



                         BENCH MARK STAMPING:  3742 C 1977
                         DESIGNATION:          845 3742 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2191
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.2' W ( -71.38670)


The bench mark is a disk set flush in top of a small curb-like seawall on the
north side of the parking area, and west of the Dutch Harbor Marine Inc. Office,
19 m (61 ft) north of the centerline of Narragansett Avenue (extended), 10 m (33
ft) west of bench mark 3742 B 1977, and 7 m (24 ft) SE of the shoreline.

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

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


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


                         BENCH MARK STAMPING:  3742 D 1977
                         DESIGNATION:          845 3742 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2192
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.2' W ( -71.38670)


The bench mark is a disk set flush in top of a small curb-like seawall that is
north of the parking area and west of the Dutch Harbor Marine Inc. Office, 13 m
(44 ft) north of the centerline of Narragansett Avenue (extended) 12 m (41 ft)
west of bench mark 3742 C 1977, in the vicinity where the shoreline meets the
seawall.



                         BENCH MARK STAMPING:  3742 E 1977
                         DESIGNATION:          845 3742 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         2193
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.2' W ( -71.38670)


The bench mark is a disk set flush in top of a small curb-like seawall north of
the parking area and west of the Dutch Harbor Marine Inc. Office, 15 m (48 ft)
west of bench mark 3742 D 1977, 7 m (24 ft) north of the centerline of
Narragansett Avenue (extended), 2.29 m (7.5 ft) east of the end of the wooden
pier, at the western end of the seawall.

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

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


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


                         BENCH MARK STAMPING:  NO 10 1930
                         DESIGNATION:          TIDAL 10 STA 16

MONUMENTATION:           Tidal Station disk                    VM#:         2194
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:  LW0631
SETTING CLASSIFICATION:  Sea wall                              OPUS PID:        
LATITUDE:   41° 29.8' N (  41.49670)          LONGITUDE:  71° 23.1' W ( -71.38500)


The bench mark is a disk set flush in top of a stone seawall south of
Narragansett Avenue, 5.06 m (16.6 ft) south of the north end of the seawall,
west of the shoreline.

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

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


                            T I D A L   D A T U M S 


Tidal datums at WEST JAMESTOWN based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           September 1977 - September 1977
     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   =  1.168
     MEAN HIGH WATER                            MHW    =  1.096
     MEAN TIDE LEVEL                            MTL    =  0.570
     MEAN SEA LEVEL                             MSL    =  0.529
     MEAN LOW WATER                             MLW    =  0.044
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     3742 A 1977                                 2.967    1.871
     3742 B 1977                                 2.353    1.257
     3742 C 1977                                 2.352    1.256
     3742 D 1977                                 2.359    1.263
     3742 E 1977                                 2.342    1.246
     NO 10 1930                                  2.788    1.692


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

                                                                                
Station ID: 8453742                         PUBLICATION DATE:  05/21/2004
Name:       WEST JAMESTOWN                                    
            RI
NOAA Chart: 13223                           Latitude:   41° 29.8' N (  41.49670)
USGS Quad:  NARRAGANSETT PIER               Longitude:  71° 23.2' W ( -71.38670)


                             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 8453742 WEST JAMESTOWN, RI

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services