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Bench Mark Sheet for 8414781, WINTERPORT, PENOBSCOT RIVER ME

Superseded Epoch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Small blue map location marker Unpublished bench mark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  4

                                                                                
Station ID: 8414781                         PUBLICATION DATE:  05/20/2004
Name:       WINTERPORT, PENOBSCOT RIVER                       
            ME
NOAA Chart: 13309                           Latitude:   44° 38.2' N (  44.63670)
USGS Quad:  BUCKSPORT                       Longitude:  68° 50.5' W ( -68.84170)


To reach the tidal bench marks from the Post Office in Winterport, proceed north
on U.S. Highway 1A for 1.1 km (0.7 mi) to Commercial Street, turn right onto
Commercial Street and go 0.24 km (0.15 mi) to Winterport Marina at the end of
Commercial Street.  The bench marks are within the marina complex and along
Water Street.  The tide gage and staff were on the marina pier.


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


                 PRIMARY BENCH MARK STAMPING:  NO 1 1970
                         DESIGNATION:          841 4781 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         1855
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Granite foundation                    OPUS PID#: BBBG22
LATITUDE:   44° 38.2' N (  44.63670)          LONGITUDE:  68° 50.5' W ( -68.84170)


The primary bench mark is a disk set flush in the granite foundation of an old
well, 18.0 m (59.0 ft) north of the center of the intersection of Commercial
Street and a paved road north, and 9.3 m (30.5 ft) west of power light pole
#575.



                         BENCH MARK STAMPING:  NO 2 1970
                         DESIGNATION:          841 4781 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:         1857
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Granite boulder                       OPUS PID:        
LATITUDE:   44° 38.2' N (  44.63670)          LONGITUDE:  68° 50.5' W ( -68.84170)


The bench mark is a disk set flush in a granite boulder, 56 m (185 ft) north of
bench mark NO 1 1970, 10.2 m (33.5 ft) north of the west end of a corrugated
pipe culvert, and 7 m (22 ft) west of the centerline of the paved road.

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

                                                                                
Station ID: 8414781                         PUBLICATION DATE:  05/20/2004
Name:       WINTERPORT, PENOBSCOT RIVER                       
            ME
NOAA Chart: 13309                           Latitude:   44° 38.2' N (  44.63670)
USGS Quad:  BUCKSPORT                       Longitude:  68° 50.5' W ( -68.84170)


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


                         BENCH MARK STAMPING:  4781-4
                         DESIGNATION:          841 4781-4

MONUMENTATION:           Tidal Station disk                    VM#:         1858
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   44° 38.2' N (  44.63670)          LONGITUDE:  68° 50.5' W ( -68.84170)


The bench mark is a disk set flush in a concrete monument, SW of the fifth shed
in a row of five sheds, 4.2 m (13.8 ft) north of a wooden bulkhead, 3.8 m (12.6
ft) south of the doorway of the shed, and 0.2 m (0.7 ft) south of the SW corner
of the fifth shed.

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

                                                                                
Station ID: 8414781                         PUBLICATION DATE:  05/20/2004
Name:       WINTERPORT, PENOBSCOT RIVER                       
            ME
NOAA Chart: 13309                           Latitude:   44° 38.2' N (  44.63670)
USGS Quad:  BUCKSPORT                       Longitude:  68° 50.5' W ( -68.84170)


                            T I D A L   D A T U M S 


Tidal datums at WINTERPORT, PENOBSCOT RIVER based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           August 1984 - September 1984
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8415490 ROCKLAND


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

     MEAN HIGHER HIGH WATER                     MHHW   =  3.828
     MEAN HIGH WATER                            MHW    =  3.689
     MEAN TIDE LEVEL                            MTL    =  1.897
     MEAN SEA LEVEL                             MSL    =  1.888
     MEAN LOW WATER                             MLW    =  0.105
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 1 1970                                   6.829    3.140
     NO 2 1970                                   7.051    3.362
     4781-4                                      4.983    1.294


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

                                                                                
Station ID: 8414781                         PUBLICATION DATE:  05/20/2004
Name:       WINTERPORT, PENOBSCOT RIVER                       
            ME
NOAA Chart: 13309                           Latitude:   44° 38.2' N (  44.63670)
USGS Quad:  BUCKSPORT                       Longitude:  68° 50.5' W ( -68.84170)


                             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 8414781 WINTERPORT, PENOBSCOT RIVER, ME

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