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Bench Mark Sheet for 9444900, Port Townsend 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Superseded Epoch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Small blue map location marker Unpublished bench mark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 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


To reach the tidal bench marks, from Seattle depart on the Winslow Ferry and
take Highway 305 north to Highway 3 towards the Hood Canal Bridge.  From the
west side of the Hood Canal Bridge travel west on Route 104 to the Port
Townsend/Chimacum turn-off onto County Road 12.  Drive 23 km (14 mi) to Route 20
and turn right.  Then go 6 km (4 mi) on Route 20 into Port Townsend.  Continue
on Water Street (Route 20) to the Washington State Ferries Dock on the right. 
The bench marks are located along Water Street (Route 20) towards Point Hudson. 
The tide gauge is located in the middle of three rooms in a wooden storage
garage at the SW corner of the dock.


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


                 PRIMARY BENCH MARK STAMPING:  TIDAL BM 18 1975
                         DESIGNATION:          944 4900 BM 18

MONUMENTATION:           Tidal Station disk                    VM#:         3145
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Concrete loading dock                 OPUS PID:        
LATITUDE:   48°  6.8' N (  48.11306)          LONGITUDE: 122° 45.5' W (-122.75814)


The primary bench mark is a disk set flush in the east corner of the Port
Townsend Bay Variety Loading Dock, 0.5 km (0.3 mi) SW of City Hall, 9.30 m (30.5
ft) NW of seawall, 6.71 m (22.0 ft) SE of the NE corner of the dock, and 1.22 m
(4.0 ft) above the parking lot ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  NO 9 1952
                         DESIGNATION:          944 4900 TIDAL 9

MONUMENTATION:           Tidal Station disk                    VM#:         1122
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID:         
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   48°  6.7' N (  48.11170)          LONGITUDE: 122° 45.5' W (-122.75800)


The bench mark is a disk set on foundation of concrete wall around the storage
tanks near Point Hudson at Union Oil Dock, 0.21 m (0.7 ft) south of the south
corner of wall, 0.21 m (0.7 ft) from east side of foundation, and 0.09 m (0.3
ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  R 257 1944
                         DESIGNATION:          R 257

MONUMENTATION:           Bench Mark disk                       VM#:         1123
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TR0559
SETTING CLASSIFICATION:  Brick wall                            OPUS PID:        
LATITUDE:   48°  7.0' N (  48.11583)          LONGITUDE: 122° 45.2' W (-122.75342)


The bench mark is a disk set vertically in SE brick wall of City Hall at the
intersection of Water and Madison Streets, 0.3 m (1 ft) from south corner of
wall, and 1.52 m (5.0 ft) above the sidewalk.



                         BENCH MARK STAMPING:  NO 10 1952
                         DESIGNATION:          944 4900 TIDAL 10

MONUMENTATION:           Tidal Station disk                    VM#:         1124
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID:         
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   48°  6.7' N (  48.11170)          LONGITUDE: 122° 45.5' W (-122.75800)


The bench mark is a disk set on top at the west corner of the concrete wall
around storage tanks on Point Hudson at Union Oil Dock, on the south side of
Water Street, 0.09 m (0.3 ft) from north side of the wall, 0.3 m (1 ft) from
west side of wall, and 1.07 m (3.5 ft) above street.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  TIDAL 13 1972
                         DESIGNATION:          944 4900 TIDAL 13

MONUMENTATION:           Tidal Station disk                    VM#:         1125
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   48°  7.0' N (  48.11603)          LONGITUDE: 122° 45.2' W (-122.75344)


The bench mark is a disk set in concrete foundation, at the south corner of the
lower section of a 1.22 x 2.44 m (4 x 8 ft) concrete sewer pumping station,
11.58 m (38.0 ft)  south of centerline of intersection of Monroe and Water
Streets, 0.76 m (2.5 ft) south of the center of an iron "sewer" manhole cover,
and 0.06 m (0.2 ft) above the ground.



                         BENCH MARK STAMPING:  NO 14 1974
                         DESIGNATION:          944 4900 TIDAL 14

MONUMENTATION:           Tidal Station disk                    VM#:         1126
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Brick wall                            OPUS PID:        
LATITUDE:   48°  6.9' N (  48.11489)          LONGITUDE: 122° 45.3' W (-122.75528)


The bench mark is a disk set vertically in the SE brick wall of the Seattle
First National Bank located on the northern corner of the intersection of Water
and Adams Streets, 30.02 m (98.5 ft) NE of the centerline of Adams Street, 12.04
m (39.5 ft) NW of the centerline of Water Street, and 0.31 m (1.0 ft) above
sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  TIDAL BM 16 1975
                         DESIGNATION:          944 4900 TIDAL BM 16

MONUMENTATION:           Tidal Station disk                    VM#:         1127
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   48°  7.0' N (  48.11642)          LONGITUDE: 122° 45.2' W (-122.75408)


The bench mark is a disk set vertically in the SE concrete wall of the Jefferson
County Memorial Athletic field at the intersection of  Washington and Madison
Streets, 2.74 m (9.0 ft) NE of the entrance to the field, 1.52 m (5.0 ft) west
of the brass cannon monument, and 1.22 m (4.0 ft) above the ground.



                         BENCH MARK STAMPING:  TIDAL BM 17 1975
                         DESIGNATION:          944 4900 TIDAL BM 17

MONUMENTATION:           Tidal Station disk                    VM#:         1128
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Window curb                           OPUS PID:        
LATITUDE:   48°  6.9' N (  48.11442)          LONGITUDE: 122° 45.4' W (-122.75736)


The bench mark is a disk set flush in the SW window curb of the  James Hastings
Building, 0.4 km (0.3 mi) SW of City Hall, at the north corner of Tyler and
Water Streets, 20.42 m (67.0 ft) NW of centerline of Water Street, 11.28 m (37.0
ft) NE of centerline of Tyler Street, in the second window curb from the
intersection, and 0.06 m (0.2 ft) above the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  4900 A 1978 TIDAL
                         DESIGNATION:          944 4900 TIDAL A

MONUMENTATION:           Tidal Station disk                    VM#:         1129
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   48°  7.0' N (  48.11686)          LONGITUDE: 122° 45.2' W (-122.75325)


The bench mark is a disk located on the west corner of the intersection of
Monroe and Washington Streets, 78.94 m (259.0 ft) NE of bench mark TIDAL BM 16
1975, 14.48 m (47.5 ft) SW of the centerline of Monroe Street, and 5.94 m (19.5
ft) north of a fire plug.  The bench mark is crimped to the top of a copper-clad
steel rod driven 14.5 m (48 ft), and encased in a 4-inch PVC pipe extending 0.15
m (0.5 ft) above the natural grade.



                         BENCH MARK STAMPING:  4900 C 1982
                         DESIGNATION:          944 4900 C

MONUMENTATION:           Tidal Station disk                    VM#:         1131
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   48°  7.0' N (  48.11611)          LONGITUDE: 122° 45.3' W (-122.75503)


The bench mark is a disk located near the north corner of the intersection of
Quincy and Washington Streets, 0.08 km (0.05 mi) SW of bench mark TIDAL BM 16
1975, 20.42 m (67.0 ft) NW of the SW corner of a tan building at 280 Quincy St.
(corner of Quincy and Washington), 2.13 m (7.0 ft) NW of a stop sign, 0.70 m
(2.3 ft) NW of the NW edge of the sidewalk, 0.37 m (1.2 ft) south of the south
corner of Jefferson County Memorial Athletic Field.  The bench mark is set  2.5
cm (0.08 ft) above the natural grade, crimped to the top of a galvanized steel
rod driven 12.2 m (40 ft) to refusal, and encased in a 4-inch PVC pipe.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  4900 D 1990
                         DESIGNATION:          944 4900 D

MONUMENTATION:           Tidal Station disk                    VM#:         3146
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AI2202
SETTING CLASSIFICATION:  Concrete footing                      OPUS PID:        
LATITUDE:   48°  6.7' N (  48.11200)          LONGITUDE: 122° 45.3' W (-122.75500)


The bench mark is a disk set flush on the concrete footing of a concrete/steel
guard rail, located at the NW head of the new Washington State Ferry Pier where
the pier face bends from running east to west, to running SE to NW, 26.91 m
(88.3 ft) east of the eastern corner of the green transformer situated at the
north head of pier, 13.50 m (44.3 ft) NW of the northern-most light pole on the
pier, 1.16 m (3.8 ft) SE of the angled corner on the NW face of pier, and 0.15 m
(0.5 ft) SE of an access panel inside of the guard rail.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


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


                         BENCH MARK STAMPING:  S 257 RESET 1983
                         DESIGNATION:          S 257 RESET

MONUMENTATION:           Bench Mark disk                       VM#:         6447
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TR2726
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   48°  6.9' N (  48.11578)          LONGITUDE: 122° 45.2' W (-122.75344)


The bench mark is a disk set flush in a concrete seawall sidewalk, 0.9 km (0.6
mi) SW of City Hall and opposite a high bluff, 57.91 m (190.0 ft) NE of NE
corner of Bayview Restaurant, 9.30 m (30.5 ft) SE of the centerline of Water
Street, 5.91m (19.4 ft) NE of SW end of seawall, and 0.52 m (1.7 ft) NW of
seaward edge of seawall.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


                            T I D A L   D A T U M S 


Tidal datums at PORT TOWNSEND, ADMIRALTY INLET based on:

     LENGTH OF SERIES:      19 Years
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (12/10/1993)         =  3.574
     MEAN HIGHER HIGH WATER                     MHHW   =  2.596
     MEAN HIGH WATER                            MHW    =  2.389
     MEAN TIDE LEVEL                            MTL    =  1.575
     MEAN SEA LEVEL                             MSL    =  1.522
     MEAN LOW WATER                             MLW    =  0.760
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (12/12/1985)         = -1.287

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     TIDAL BM 18 1975                            5.534    3.145
     NO 9 1952                                   3.521    1.132
     R 257 1944                                  6.196    3.807
     NO 10 1952                                  5.216    2.827
     TIDAL 13 1972                               4.323    1.934
     NO 14 1974                                  4.946    2.557
     TIDAL BM 16 1975                            6.339    3.950
     TIDAL BM 17 1975                            4.829    2.440
     4900 A 1978 TIDAL                           4.915    2.526
     4900 C 1982                                 4.980    2.591
     4900 D 1990                                 5.260    2.871
     S 257 RESET 1983                            5.417    3.028


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 10 of 10

                                                                                
Station ID: 9444900                         PUBLICATION DATE:  04/21/2003
Name:       PORT TOWNSEND, ADMIRALTY INLET                    
            WA
NOAA Chart: 18464                           Latitude:   48°  6.7' N (  48.11170)
USGS Quad:  NORDLAND                        Longitude: 122° 45.5' W (-122.75800)


                             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 9444900 Port Townsend, WA

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