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Bench Mark Sheet for 9448614, BOWMAN BAY, FIDALGO ISLAND WA

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 9448614                         PUBLICATION DATE:  01/23/2004
Name:       RESERVATION BAY                                   
            WA
NOAA Chart: 18427                           Latitude:   48° 24.9' N (  48.41500)
USGS Quad:  DECEPTION PASS                  Longitude: 122° 39.1' W (-122.65200)


To reach the tidal bench marks from Anacortes, proceed 16 km (10 mi) south to
the south coast of Fidalgo Island and Deception Pass State Park.  The bench
marks are within the park, along the coastline of Bowman (Reservation) Bay from
Rosario Head to the park pier.  The tide gage and staff were located on the
south side of the pier, 122 m (400 ft) west of the east end of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  BM 8 1973
                         DESIGNATION:          944 8614 TIDAL 8

MONUMENTATION:           Tidal Station disk                    VM#:         9261
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   48° 24.9' N (  48.41500)          LONGITUDE: 122° 39.1' W (-122.65200)


The primary bench mark is a disk set in the NW corner of the concrete foundation
of the Deception Pass State Park service shed, 4 m (12 ft) east of the NW corner
of the foundation, and 1 m (3 ft) NW of the NW corner of the shed.



                         BENCH MARK STAMPING:  BM 6 1973
                         DESIGNATION:          944 8614 TIDAL 6

MONUMENTATION:           Tidal Station disk                    VM#:         9259
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   48° 24.9' N (  48.41500)          LONGITUDE: 122° 39.1' W (-122.65200)


The bench mark is a disk set in the NW corner of the concrete foundation of the
second recreation shelter, with a 6 m (20 ft) long cook pit, north of the
Deception Pass State Park parking lot.

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

                                                                                
Station ID: 9448614                         PUBLICATION DATE:  01/23/2004
Name:       RESERVATION BAY                                   
            WA
NOAA Chart: 18427                           Latitude:   48° 24.9' N (  48.41500)
USGS Quad:  DECEPTION PASS                  Longitude: 122° 39.1' W (-122.65200)


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


                         BENCH MARK STAMPING:  BM 7 1973
                         DESIGNATION:          944 8614 TIDAL 7

MONUMENTATION:           Tidal Station disk                    VM#:         9260
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   48° 24.9' N (  48.41500)          LONGITUDE: 122° 39.1' W (-122.65200)


The bench mark is a disk set in the SW corner of the concrete foundation of the
first recreation shelter north of the Deception Pass State Park parking lot, 79
m (260 ft) SE of bench mark BM 6 1973, and 2 m (5 ft) NE of the SW support pole
of the shelter.

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

                                                                                
Station ID: 9448614                         PUBLICATION DATE:  01/23/2004
Name:       RESERVATION BAY                                   
            WA
NOAA Chart: 18427                           Latitude:   48° 24.9' N (  48.41500)
USGS Quad:  DECEPTION PASS                  Longitude: 122° 39.1' W (-122.65200)


                            T I D A L   D A T U M S 


Tidal datums at RESERVATION BAY based on:

     LENGTH OF SERIES:      2 YEARS
     TIME PERIOD:           November 1973 - October 1975
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9444900 PORT TOWNSEND, ADMIRALTY INLET


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

     HIGHEST OBSERVED WATER LEVEL (01/15/1974)         =  3.200
     MEAN HIGHER HIGH WATER                     MHHW   =  2.352
     MEAN HIGH WATER                            MHW    =  2.154
     MEAN TIDE LEVEL                            MTL    =  1.450
     MEAN SEA LEVEL                             MSL    =  1.410
     MEAN LOW WATER                             MLW    =  0.746
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/07/1974)         = -1.137

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     BM 8 1973                                   4.018    1.864
     BM 6 1973                                   3.875    1.721
     BM 7 1973                                   2.937    0.783


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

                                                                                
Station ID: 9448614                         PUBLICATION DATE:  01/23/2004
Name:       RESERVATION BAY                                   
            WA
NOAA Chart: 18427                           Latitude:   48° 24.9' N (  48.41500)
USGS Quad:  DECEPTION PASS                  Longitude: 122° 39.1' W (-122.65200)


                             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 9448614 BOWMAN BAY, FIDALGO ISLAND, WA

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