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Bench Mark Sheet for 9462645, Biorka Village, Biverly Inlet AK

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 9462645                         PUBLICATION DATE:  05/26/2010
Name:       BIORKA VILLAGE, BEAVER INLET                      
            AK
NOAA Chart: 16520                           Latitude:   53° 49.7' N (  53.82892)
USGS Quad:  UNALASKA (C-1)                  Longitude: 166° 13.0' W (-166.21625)


To reach the tidal bench marks by boat from the city dock in Dutch Harbor,
proceed NNE 19.0 km (10.3 nm) to Priest Rock, turn right and proceed ESE 10.0 km
(5.4 nm) to Unalga Pass, turn right and proceed SSE 12.0 km (6.5 nm) to the
entrance to Beaver Inlet, turn right and proceed SW 10.0 km (5.4 nm) to the
rocky point at the NE corner of the entrance to Udamat Bay on the south side of
Beaver Inlet.  The bench marks are located in rock outcrops along the eastern
shore of Udamat Bay, south from the entrance.  The tide station was located at
the second cobble beach south of the entrance to the bay.


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


                 PRIMARY BENCH MARK STAMPING:  BM 1 1934
                         DESIGNATION:          946 2645 TIDAL 1

MONUMENTATION:           Bench Mark disk                       VM#:        18572
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   53° 49.7' N (  53.82830)          LONGITUDE: 166° 13.0' W (-166.21700)


The primary bench mark is a disk set on a rock pinnacle on the furthest west
rock outcrop from Biorka Village, 23.10 m (76.1 ft) west from tidal bench mark
946 2645 TIDAL 2, 18 m (58 ft) SW from the base of the grass bluff, 5 m (18 ft)
east from the seaward point of the outcrop, and 5 m (16 ft) SW from the
beginning of the bare rock point and the end of the vegetation.

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

                                                                                
Station ID: 9462645                         PUBLICATION DATE:  05/26/2010
Name:       BIORKA VILLAGE, BEAVER INLET                      
            AK
NOAA Chart: 16520                           Latitude:   53° 49.7' N (  53.82892)
USGS Quad:  UNALASKA (C-1)                  Longitude: 166° 13.0' W (-166.21625)


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


                         BENCH MARK STAMPING:  BM 2 1934
                         DESIGNATION:          946 2645 TIDAL 2

MONUMENTATION:           Bench Mark disk                       VM#:        18573
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   53° 49.7' N (  53.82830)          LONGITUDE: 166° 13.0' W (-166.21700)


The bench mark is a disk set on the south side of a rock face, 23.10 m (76.1 ft)
east from 946 2645 TIDAL 1, a slope distance of 12 m (41 ft) SSE from the top of
the grass bluff above the monument, and 1 m (4 ft) north from seaward point of
rock.



                         BENCH MARK STAMPING:  BM 3 1934
                         DESIGNATION:          946 2645 TIDAL 3

MONUMENTATION:           Bench Mark disk                       VM#:        18574
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   53° 49.7' N (  53.82830)          LONGITUDE: 166° 12.9' W (-166.21500)


The bench mark is a disk set in a rock outcrop, 9 m (30 ft) west from the top of
the high grassy knob, 7 m (24 ft) east from the seaward extent of the outcrop at
low tide, 5 m (17 ft) west from the rock face/beginning of vegetation, and 4 m
(13 ft) south from the north side of the rock outcrop.

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

                                                                                
Station ID: 9462645                         PUBLICATION DATE:  05/26/2010
Name:       BIORKA VILLAGE, BEAVER INLET                      
            AK
NOAA Chart: 16520                           Latitude:   53° 49.7' N (  53.82892)
USGS Quad:  UNALASKA (C-1)                  Longitude: 166° 13.0' W (-166.21625)


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


                         BENCH MARK STAMPING:  2645 A 2007
                         DESIGNATION:          946 2645 A

MONUMENTATION:           Tidal Station disk                    VM#:        18575
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID#: BBBF92
LATITUDE:   53° 49.8' N (  53.83000)          LONGITUDE: 166° 13.0' W (-166.21700)


The bench mark is a disk set on a large rock outcrop west of Biorka Village, 15
m (50 ft) WNW from a 6 m (20 ft) tall rock point and the beginning of
vegetation, 10 m (34 ft) from the south side of the rock point at high tide, 6 m
(18 ft) east from the seaward extent of rock point, 3.10 m (10.2 ft) south from
the north side of the outcrop.



                         BENCH MARK STAMPING:  2645 B 2007
                         DESIGNATION:          946 2645 B

MONUMENTATION:           Tidal Station disk                    VM#:        18576
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   53° 49.7' N (  53.82830)          LONGITUDE: 166° 12.9' W (-166.21500)


The bench mark is a disk set in a rock outcrop 50 m (165 ft) NNW from the
northern face of large rock outcrop that is at the south end of the cobble
beach, 8 m (27 ft) NNE from the seaward extent of the rock point at low tide, 5
m ( 15 ft) WSW slope distance from the top of the grassy knoll, 4 m (12 ft) WSW
from the base of bluff, 1 m (3 ft) WSW from the end of vegetation and the rock
face.

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

                                                                                
Station ID: 9462645                         PUBLICATION DATE:  05/26/2010
Name:       BIORKA VILLAGE, BEAVER INLET                      
            AK
NOAA Chart: 16520                           Latitude:   53° 49.7' N (  53.82892)
USGS Quad:  UNALASKA (C-1)                  Longitude: 166° 13.0' W (-166.21625)


                            T I D A L   D A T U M S 


Tidal datums at BIORKA VILLAGE, BEAVER INLET based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           July 2007 - July 2007
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9459881 KING COVE, DEER PASSAGE, PACIFIC OCEAN


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.554
     MEAN HIGH WATER                            MHW    =  1.422
     MEAN TIDE LEVEL                            MTL    =  0.887
     MEAN SEA LEVEL                             MSL    =  0.877
     MEAN LOW WATER                             MLW    =  0.352
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     BM 1 1934                                   4.153    2.731
     BM 2 1934                                   3.763    2.341
     BM 3 1934                                   3.217    1.795
     2645 A 2007                                 3.649    2.227
     2645 B 2007                                 2.814    1.392


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

                                                                                
Station ID: 9462645                         PUBLICATION DATE:  05/26/2010
Name:       BIORKA VILLAGE, BEAVER INLET                      
            AK
NOAA Chart: 16520                           Latitude:   53° 49.7' N (  53.82892)
USGS Quad:  UNALASKA (C-1)                  Longitude: 166° 13.0' W (-166.21625)


                             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 9462645 Biorka Village, Biverly Inlet, AK

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