U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 10/25/1984
Station ID: 9447427 SUPERCEDED DATE: 04/21/2003
Name: EDMONDS, PUGET SOUND
WASHINGTON
NOAA Chart: 18446 Latitude: 47° 48.8' N
USGS Quad: EDMONDS WEST Longitude: 122° 23.0' W
To reach the tidal bench marks from the intersection of the Burlington North-
ern railroad tracks and Main Street in Edmonds, proceed west to the Washington
State Ferry Pier. The bench marks are located in the vicincity of Main Street
and the pier. The gage site was at the west end of the ferry pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1927
MONUMENTATION: Survey Disk VM#: 9195
AGENCY: PID#: SY0126
SETTING CLASSIFICATION: Concrete Base
The bench mark is set into the top of the SW corner of a former concrete base
for a railroad signal tower, 225 feet (69 m) north of the center of the Main
Street and railroad crossing intersection, and 30 feet (9 m) east of the
centerline of the railroad tracks.
BENCH MARK STAMPING: 7427 H 1977
MONUMENTATION: Survey Disk VM#: 9196
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Cap
The bench mark is in the concrete cap of a sheet pile bulkhead of the extreme
west end of the filled portion of the Washington State Ferry Dock, 492 feet (150
m) west of the toll booth building, 43 feet (13 m) SW of a fire hydrant, 24.6
feet (7.5 m) north of the road leading to the ferry slip, 20 feet (6 m) south of
a light pole, and 0.5 foot (0.2 m) east of a north-south pipe railing.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 10/25/1984
Station ID: 9447427 SUPERCEDED DATE: 04/21/2003
Name: EDMONDS, PUGET SOUND
WASHINGTON
NOAA Chart: 18446 Latitude: 47° 48.8' N
USGS Quad: EDMONDS WEST Longitude: 122° 23.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: BM NO 5 1966
MONUMENTATION: Survey Disk VM#: 9197
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Curb
The bench mark is set flush into the top of the east concrete curb of the
north-south road on the east side of Edmonds Yacht Club, 92 feet (28 m) NE of
the NE corner of the Northwest Fur Breeders Cooperative building.
BENCH MARK STAMPING: TIDAL 9 1969
MONUMENTATION: Survey Disk VM#: 9198
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Post
The bench mark is about 2.5 feet (0.8 m) south of the SW corner of the Edmonds
Yacht Club building, in a shrubbery bed between the sidewalk and the building,
set into the top of a concrete post projecting 0.3 foot (0.1 m) above ground
level.
BENCH MARK STAMPING: N 7 1956 RESET
MONUMENTATION: Survey Disk VM#: 9199
AGENCY: PID#: SY0128
SETTING CLASSIFICATION: Concrete Wall
The bench mark is set into the top of a 3.5 foot (1.1 m) high concrete wall
around a flower bed at the NW corner of the Great Northern Railroad station, 32
feet (10.8 m) SE of the SE rail of the main track, 3.5 feet (1.1 m) north of the
north corner of the depot, and 1.5 feet (0.5 m) above the asphalt parking
surface.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 10/25/1984
Station ID: 9447427 SUPERCEDED DATE: 04/21/2003
Name: EDMONDS, PUGET SOUND
WASHINGTON
NOAA Chart: 18446 Latitude: 47° 48.8' N
USGS Quad: EDMONDS WEST Longitude: 122° 23.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: TS 31.30 BM 31.28
MONUMENTATION: Survey Disk VM#: 9200
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Post
The bench mark is set into the top of an 0.7 foot (0.2 m) diameter concrete
monument projecting 0.1 foot (0.03 m) above ground, 165 feet (50 m) SE of the
centerline of the intersection of Admiral Way and Dayton Street, 57 feet (17 m)
SW of the centerline of Dayton Street, 14.4 feet (4.4 m) SW of a witness post
and, 8 feet (2 m) NW of the west rail of the main track of the Great Northern
Railroad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 10/25/1984
Station ID: 9447427 SUPERCEDED DATE: 04/21/2003
Name: EDMONDS, PUGET SOUND
WASHINGTON
NOAA Chart: 18446 Latitude: 47° 48.8' N
USGS Quad: EDMONDS WEST Longitude: 122° 23.0' W
T I D A L D A T U M S
Tidal datums at EDMONDS, PUGET SOUND based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: MARCH - MAY 1978
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 9447130 SEATTLE
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (11/15/1977) = 12.91
MEAN HIGHER HIGH WATER MHHW = 10.91
MEAN HIGH WATER MHW = 10.06
MEAN TIDE LEVEL MTL = 6.43
MEAN LOW WATER MLW = 2.80
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (05/24/1978) = -2.80
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 1 1927 15.86 5.80
7427 H 1977 16.68 6.62
BM NO 5 1966 14.94 4.88
TIDAL 9 1969 15.57 5.51
N 7 1956 RESET 15.81 5.75
TS 31.30 BM 31.28 13.02 2.96
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 10/25/1984
Station ID: 9447427 SUPERCEDED DATE: 04/21/2003
Name: EDMONDS, PUGET SOUND
WASHINGTON
NOAA Chart: 18446 Latitude: 47° 48.8' N
USGS Quad: EDMONDS WEST Longitude: 122° 23.0' 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.