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Bench Mark Sheet for 9445296, SEABECK, HOOD CANAL 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


To reach the tidal bench marks from the post office in Seabeck, Washington,
proceed 0.40 km (0.25 mi) NE along Seabeck Highway NW to the wood pier at
Seabeck Marina.  The bench marks are located along both sides of Seabeck Highway
NW, north and south of the pier.  The tide gage and staff were mounted at the NE
corner of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  5296 A 1978
                         DESIGNATION:          944 5296 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9042
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The bench mark is a disk set flush in top of a concrete sea wall on north side
of the pier, 90 m (295 ft) SE of the seaward end of the pier, 24.23 m (79.5 ft)
NW of the centerline of the road, 10 m (32 ft) NW of a telephone pole and 9 m
(30 ft) NW from the land end of the pier, and level with the surrounding
pavement.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


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


                         BENCH MARK STAMPING:  5296 B 1978
                         DESIGNATION:          944 5296 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9043
AGENCY:                  National Ocean  Survey (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete base for flagpole            OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The bench mark is a disk set flush in the concrete base for the flag pole at the
Seabeck Post Office, 13.26 m (43.5 ft) NW of the centerline of Seabeck Highway
NW, 6.22 m (20.4 ft) SW of the SW corner of the village post office and 0.34 m
(1.1 ft) NE of the flagpole.



                         BENCH MARK STAMPING:  5296 C 1978
                         DESIGNATION:          944 5296 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9044
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete footing                      OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The bench mark is a disk set flush into the concrete footing supporting the
vertical members of a 4 m (12 ft) high timber arched entrance structure marking
the entrance to the Seabeck Conference Grounds, set between between two westerly
vertical posts that support the south end of the gateway, 50 m (164 ft) SW from
the Seabeck Post Office, 5.80 m (19.0 ft) NE of a large storm sewer, 2.44 m (8.0
ft) NW of the west end of the wood bridge leading over a lagoon to the Seabeck
Conference Grounds.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


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


                         BENCH MARK STAMPING:  5296 D 1978
                         DESIGNATION:          944 5296 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         9045
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The bench mark is a disk set flush in the top of a concrete sea wall which leads
NW from the NE landward corner of the wood pier at Seabeck Marina, 26 m (86 ft)
NE of the east die of the Seabeck Landing General Store, 24.23 m (79.5 ft) NE of
the centerline of Seabeck Highway NW and 19.99 m (65.6 ft) NE of bench mark 5296
A 1978.



                         BENCH MARK STAMPING:  NO 2 1935
                         DESIGNATION:          944 5296 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:         9046
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:        
SETTING CLASSIFICATION:  Concrete slab                         OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The primary bench mark is a disk set flush in top of a concrete slab which is
the top of an abandoned septic tank, 0.40 km (0.25 mi) NE along Seabeck Highway
NW from the post office, behind and between the beach and a summer home, 14 m
(45 ft) north of the NW corner of the summer home and 11 m ( 36 ft) west of the
SW corner of the first house, 0.61 m (2.0 ft) east of the west edge and 15 cm
(0.5 ft) north of the south edge of the concrete slab.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


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


                         BENCH MARK STAMPING:  NO 4 1935
                         DESIGNATION:          944 5296 TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:         9047
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:        
SETTING CLASSIFICATION:  Concrete slab                         OPUS PID:        
LATITUDE:   47° 38.5' N (  47.64170)          LONGITUDE: 122° 49.7' W (-122.82800)


The bench mark is a disk about 0.40 km (0.25 mi) SW along Seabeck Highway NW
from the post office, set flush in top of a concrete slab which is the top of an
abandoned septic tank, SW of the south entrance to the Seabeck Conference
Grounds, 22 m (71 ft) SW of utility pole No. C240 with a single guy wire, 8 m
(26 ft) SE of the centerline of the road, 1.58 m (5.2 ft) SW of the NW corner
and 0.24 m (0.8 ft) SE of the NW edge of the concrete slab.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


                            T I D A L   D A T U M S 


Tidal datums at SEABECK, HOOD CANAL based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           February 1978 - February 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9447130 SEATTLE, PUGET SOUND


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

     MEAN HIGHER HIGH WATER                     MHHW   =  3.504
     MEAN HIGH WATER                            MHW    =  3.214
     MEAN TIDE LEVEL                            MTL    =  2.063
     MEAN SEA LEVEL                             MSL    =  2.058
     MEAN LOW WATER                             MLW    =  0.912
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5296 A 1978                                 4.533    1.319
     5296 B 1978                                 4.469    1.255
     5296 C 1978                                 4.176    0.962
     5296 D 1978                                 4.305    1.091
     NO 2 1935                                   4.703    1.489
     NO 4 1935                                   4.344    1.130


Foot Notes:

Bench marks NO 2 1935 and NO 4 1935 are based on one differential leveling
connection and do not meet the quality control standards of the NOS. Therefore,
caution should be used when deriving elevations for these marks.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  6

                                                                                
Station ID: 9445296                         PUBLICATION DATE:  08/03/2004
Name:       SEABECK, HOOD CANAL                               
            WA
NOAA Chart: 18441                           Latitude:   47° 38.5' N (  47.64170)
USGS Quad:  WILDCAT LAKE                    Longitude: 122° 49.7' W (-122.82800)


                             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 9445296 SEABECK, HOOD CANAL, WA

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