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Superseded Bench Mark Sheet for 9451497, Saginaw Bay, Kuiu Island AK

Present Epoch

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  4

                                                   PUBLICATION DATE:  10/23/2000
Station ID: 9451497                                SUPERCEDED DATE:   04/21/2003
Name:       SAGINAW BAY, KUIU ISLAND                          
            ALASKA
NOAA Chart: 17368                                  Latitude:         56° 54.2' N
USGS Quad:  PORT ALEXANDER (D-1)                   Longitude:       134° 18.2' W


To reach the tidal bench marks from Cornwallis Point Light on Kuiu Island,
proceed 3.7 km (2.0 nm) SW across Saginaw Bay to the small peninsula which
points NE and is distinguished from the surrounding terrain by its light colored
brush, and marks the western entrance of a small bay at the SW shore of the
entrance to the Saginaw Bay. The bench marks are along the SE shore of the
peninsula.  The tide gage and sensor were also on the SE shore of the peninsula.


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


                 PRIMARY BENCH MARK STAMPING:  NO 1 1967
                         DESIGNATION:          945 1497 TIDAL 1

MONUMENTATION:           Tidal Station disk                        VM#:    13099
AGENCY:                  US Coast & Geodetic Survey (USC&GS)       PID:         
SETTING CLASSIFICATION:  Rock outcrop


The primary bench mark is a disk set on a high rock along the SE shore of the
small peninsula, about 100 m (328 ft) NNE of bench mark NO 3 1967, 20 m (66 ft)
NNE of bench mark NO 2 1967, 5 m (16 ft) SE of the brush line, and 3 M (10 ft)
NW of the apparent high water line.



                         BENCH MARK STAMPING:  NO 2 1967
                         DESIGNATION:          945 1497 TIDAL 2

MONUMENTATION:           Tidal Station disk                        VM#:    13100
AGENCY:                  US Coast & Geodetic Survey (USC&GS)       PID:         
SETTING CLASSIFICATION:  Rock outcrop


The bench mark is a disk set along the SE shore of the small peninsula, about 80
m (262 ft) NNE of bench mark NO 3 1967, 20 m (66 ft) SSW of bench mark NO 1
1967, 10 m (33 ft) NW of the apparent high water line, and 5 m (16 ft) SE of the
brush line.

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

                                                   PUBLICATION DATE:  10/23/2000
Station ID: 9451497                                SUPERCEDED DATE:   04/21/2003
Name:       SAGINAW BAY, KUIU ISLAND                          
            ALASKA
NOAA Chart: 17368                                  Latitude:         56° 54.2' N
USGS Quad:  PORT ALEXANDER (D-1)                   Longitude:       134° 18.2' W


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


                         BENCH MARK STAMPING:  NO 3 1967
                         DESIGNATION:          945 1497 TIDAL 3

MONUMENTATION:           Tidal Station disk                        VM#:    13101
AGENCY:                  US Coast & Geodetic Survey (USC&GS)       PID:         
SETTING CLASSIFICATION:  Rock outcrop


The bench mark is a disk set on a high rock located along the SE shore of a
small peninsula, about 100 m (328 ft) SSW of bench mark NO 1 1967, about 80 m
(262 ft) SSW of bench mark NO 2 1967, 25 m (82 ft) east of the tree line, and
about 8 m (26 ft) NW of the apparent high water line.



                         BENCH MARK STAMPING:  1497 D 1989
                         DESIGNATION:          945 1497 D

MONUMENTATION:           Tidal Station disk                        VM#:    13102
AGENCY:                  National Ocean Service (NOS)              PID:         
SETTING CLASSIFICATION:  Rock outcrop


The bench mark is a disk set in bedrock on a small ledge that extends 2 m (6 ft)
out from a cliff face, 45 m (147 ft) SW of bench mark NO 2 1967, 30 m (98 ft)
WNW of bench mark NO 3 1967, and 2 m (7 ft) above the apparent high water line.



                         BENCH MARK STAMPING:  1497 E 1989
                         DESIGNATION:          945 1497 E

MONUMENTATION:           Tidal Station disk                        VM#:    13103
AGENCY:                  National Ocean Service (NOS)              PID:         
SETTING CLASSIFICATION:  Rock outcrop


The bench mark is a disk set in bedrock 94.34 m (309.5 ft) south of bench mark
NO 2 1967, 19.05 m (62.5 ft) SSE of bench mark NO 3 1967, 10 m (33 ft) ENE of
the treeline on a small east-west running outcrop, and 5 m (16 ft) above the
apparent high water line.

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

                                                   PUBLICATION DATE:  10/23/2000
Station ID: 9451497                                SUPERCEDED DATE:   04/21/2003
Name:       SAGINAW BAY, KUIU ISLAND                          
            ALASKA
NOAA Chart: 17368                                  Latitude:         56° 54.2' N
USGS Quad:  PORT ALEXANDER (D-1)                   Longitude:       134° 18.2' W


                            T I D A L   D A T U M S 


Tidal datums at SAGINAW BAY, KUIU ISLAND based on:

     LENGTH OF SERIES:      65 hws and 64 lws
     TIME PERIOD:           March 14 - April 16, 1989
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  9450460 KETCHIKAN, TONGASS NARROWS


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

     MEAN HIGHER HIGH WATER                     MHHW   =  4.167
     MEAN HIGH WATER                            MHW    =  3.917
     MEAN SEA LEVEL                             MSL    =  2.210
     MEAN TIDE LEVEL                            MTL    =  2.188
     MEAN LOW WATER                             MLW    =  0.460
     MEAN LOWER LOW WATER                       MLLW   =  0.000



Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 1 1967                                   6.368    2.452
     NO 2 1967                                   5.191    1.275
     NO 3 1967                                   6.137    2.221
     1497 D 1989                                 5.036    1.120
     1497 E 1989                                 5.367    1.450


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

                                                   PUBLICATION DATE:  10/23/2000
Station ID: 9451497                                SUPERCEDED DATE:   04/21/2003
Name:       SAGINAW BAY, KUIU ISLAND                          
            ALASKA
NOAA Chart: 17368                                  Latitude:         56° 54.2' N
USGS Quad:  PORT ALEXANDER (D-1)                   Longitude:       134° 18.2' W


                             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 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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Revised: 08/08/2018
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