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Bench Mark Sheet for 9451467, Red Bluff Bay, Baranof Island 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Superseded Epoch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Small blue map location marker Unpublished bench mark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: 9451467                         PUBLICATION DATE:  08/13/2013
Name:       RED BLUFF BAY, BARANOF ISLAND                     
            AK
NOAA Chart: 17336                           Latitude:   56° 51.4' N (  56.85670)
USGS Quad:  PORT ALEXANDER                  Longitude: 134° 43.4' W (-134.72300)


To reach the tidal bench marks from Sitka, AK, by boat, start at the rock jetty
entrance to the small boat harbor and proceed for 0.36 nm (0.67 km) on course, 
then proceed for 2.08 nm (3.84km) past Passage Islands, then proceed for 14.99
nm (27.76 km) past Biorka Island, then proceed for 52.87nm (97.91 km) to the
most southern point of Baranof Island, then proceed for 3.40 nm (6.30 km) to
past Wooden Island, then proceed for 29.55 nm (54.73 km), then proceed for 11.74
nm (21.73km), then proceed for 1.29 nm (2.39 km) to the entrance of Red Bluff
Bay, then proceed for 0.21 nm (0.40 km), then proceed for 0.18 nm (0.34 km),
then proceed for 0.27 nm (0.49 km), then proceed for 0.17 nm (0.31 km) then
proceed for 0.34 nm (0.63 km), and finally, proceed for 0.29 nm (0.54 km).  The
bench marks are located on the northeastern portion of Red Bluff Bay, at an old
cannery site, set in boulders and bedrock along the beach.   


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


                 PRIMARY BENCH MARK STAMPING:  A 1926
                         DESIGNATION:          945 1467 A

MONUMENTATION:           Survey disk                           VM#:        14132
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   56° 51.3' N (  56.85575)          LONGITUDE: 134° 43.5' W (-134.72461)


The primary benchmark is a set flush in a crevice in the top of a large pointed
boulder,  2.6 km (8530 ft) NE of the reference peak across the bay, 65.64 m
(215.35 ft) SE of bench mark 945 1467 TIDAL 1, 65.49 m (214.86 ft) SE of bench
mark 945 1467 B, 59.56 m (195.41 ft) WNW of bench mark 945 1467 TIDAL 3, and
36.12 m (118.50 ft) WNW of bench mark 945 1467 C.

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

                                                                                
Station ID: 9451467                         PUBLICATION DATE:  08/13/2013
Name:       RED BLUFF BAY, BARANOF ISLAND                     
            AK
NOAA Chart: 17336                           Latitude:   56° 51.4' N (  56.85670)
USGS Quad:  PORT ALEXANDER                  Longitude: 134° 43.4' W (-134.72300)


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


                         BENCH MARK STAMPING:  B 1926
                         DESIGNATION:          945 1467 B

MONUMENTATION:           Survey disk                           VM#:        14133
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   56° 51.4' N (  56.85622)          LONGITUDE: 134° 43.5' W (-134.72528)


The benchmark is set flush on top of a large flat boulder adjacent to an old
cannery boiler on the extreme eastern edge of the grassy beach, 2.9 km (9514 ft)
NE of the reference peak across the bay, 123.77 m (406.07 ft) WNW of the bench
mark 945 1467 TIDAL 3, 100.54 m (329.86 ft) WNW of bench mark 945 1467 C, 65.49
m (214.86 ft) NNW of bench mark 945 1467 A, and 22.29 m (73.13 ft) NE of bench
mark 945 1467 TIDAL 1.



                         BENCH MARK STAMPING:  C 1926
                         DESIGNATION:          945 1467 C

MONUMENTATION:           Survey disk                           VM#:        14134
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   56° 51.3' N (  56.85544)          LONGITUDE: 134° 43.5' W (-134.72442)


The benchmark is set flush on the point of a ledge of bedrock, 2.2 km (7218 ft)
ENE of  the reference peak across the bay, 100.54 m (329.86 ft) ESE of bench
mark 945 1467 B, 97.16 m (318.77 ft) SE of bench mark 945 1467 TIDAL 1, 36.12 m
(118.50 ft) ESE of bench mark 945 1467 A, and 23.56 m (77.30 ft) WNW of bench
mark 945 1467 3.

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

                                                                                
Station ID: 9451467                         PUBLICATION DATE:  08/13/2013
Name:       RED BLUFF BAY, BARANOF ISLAND                     
            AK
NOAA Chart: 17336                           Latitude:   56° 51.4' N (  56.85670)
USGS Quad:  PORT ALEXANDER                  Longitude: 134° 43.4' W (-134.72300)


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


                         BENCH MARK STAMPING:  1 1926
                         DESIGNATION:          945 1467 TIDAL 1

MONUMENTATION:           Survey disk                           VM#:        14135
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   56° 51.4' N (  56.85608)          LONGITUDE: 134° 43.5' W (-134.72553)


The benchmark is a set flush in a boulder near the center of the obvious flat
grassy beach, 2.9 km (9514 ft) NE  of the reference peak across the bay (Mt.
Harding), 119.49 m (392.03 ft) NW of bench mark 945 1467 TIDAL 3, 97.16 m
(318.77 ft) NW of bench mark 945 1467 C, 65.64 m (215.35 ft) WNW of bench mark
945 1467 A , and 22.29 m (73.13 ft) SW of bench mark 945 1467 B. 

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

                                                                                
Station ID: 9451467                         PUBLICATION DATE:  08/13/2013
Name:       RED BLUFF BAY, BARANOF ISLAND                     
            AK
NOAA Chart: 17336                           Latitude:   56° 51.4' N (  56.85670)
USGS Quad:  PORT ALEXANDER                  Longitude: 134° 43.4' W (-134.72300)


                            T I D A L   D A T U M S 


Tidal datums at RED BLUFF BAY, BARANOF ISLAND based on:

     LENGTH OF SERIES:      30 Days
     TIME PERIOD:           May 30 2013 - June 28 2013
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9451054 PORT ALEXANDER, BARANOF ISLAND


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

     MEAN HIGHER HIGH WATER                     MHHW   =  3.904
     MEAN HIGH WATER                            MHW    =  3.631
     MEAN SEA LEVEL                             MSL    =  2.069
     MEAN TIDE LEVEL                            MTL    =  2.048
     MEAN LOW WATER                             MLW    =  0.465
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     A 1926                                      2.916   -0.715
     B 1926                                      3.312   -0.319
     C 1926                                      2.587   -1.043
     1 1926                                      2.694   -0.937


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

                                                                                
Station ID: 9451467                         PUBLICATION DATE:  08/13/2013
Name:       RED BLUFF BAY, BARANOF ISLAND                     
            AK
NOAA Chart: 17336                           Latitude:   56° 51.4' N (  56.85670)
USGS Quad:  PORT ALEXANDER                  Longitude: 134° 43.4' W (-134.72300)


                             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 9451467 Red Bluff Bay, Baranof Island, AK

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