U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 04/20/1984
Station ID: 9446254 SUPERCEDED DATE: 04/21/2003
Name: BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR
WASHINGTON
NOAA Chart: 18448 Latitude: 47° 23.7' N
USGS Quad: VASHON Longitude: 122° 27.8' W
To reach the tidal bench marks in City of Burton, proceed north to the west
shore of Quartermaster Harbor, then north to the Quartermasters Yacht Club. The
bench marks are located along road leading to the yacht club and the tide gage
and staff were lcoated on the yacht club dock.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: TIDAL 1 1975
MONUMENTATION: Survey Disk VM#: 9118
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Footing
The bench mark is set in the concrete footing of a boat house on the west shore
of Quartermaster Harbor, 285 feet (87 m) north of the inshore end of the pier of
the Quartermaster Yacht Club at the base of the bluff.
BENCH MARK STAMPING: TIDAL 2 1975
MONUMENTATION: Survey Disk VM#: 9119
AGENCY: PID:
SETTING CLASSIFICATION: Rock
The bench mark is set in a 1 foot (0.3 m) high boulder on the beach, 324 feet
(99 m) north of the inshore end of the pier ofthe Quartermaster Yacht Club, 39
feet (12 m) NNE of Bench Mark Tidal 1 1975 and 12 feet (4 m) east of the
bulkhead in front of a private residence.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 04/20/1984
Station ID: 9446254 SUPERCEDED DATE: 04/21/2003
Name: BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR
WASHINGTON
NOAA Chart: 18448 Latitude: 47° 23.7' N
USGS Quad: VASHON Longitude: 122° 27.8' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: TIDAL 3 1975
MONUMENTATION: Survey Disk VM#: 9120
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Curb
The bench mark is set in a concrete curb along the east side of the driveway
leading to the Quartermaster Harbor Marina, 405 feet (123 m) north of the
centerline intersection of 103 Avenue SW and 240 Street SW, 18.9 feet (5.8 m) NW
of the NW corner of the Burton Post Office, 8.2 feet (2.5 m) NW of a flagpole
and flush with the curb.
BENCH MARK STAMPING: TIDAL 4 1975
MONUMENTATION: Survey Disk VM#: 9121
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set in the top of the NE corner of a 2 foot (1 m) square
concrete base of a steel pole that supports a SHELL sign, 92.2 feet (28.1 m) NNW
of the centerline intersection of 103 Avenue SW and 240 Street SW, 42.5 feet
(13.0 m) west of the centerline of 103 Avenue SW, and 0.2 foot (0.1 m) above
ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 04/20/1984
Station ID: 9446254 SUPERCEDED DATE: 04/21/2003
Name: BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR
WASHINGTON
NOAA Chart: 18448 Latitude: 47° 23.7' N
USGS Quad: VASHON Longitude: 122° 27.8' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 2 1917
MONUMENTATION: Survey Disk VM#: 9122
AGENCY: PID#: SY0647
SETTING CLASSIFICATION: Concrete Post
The bench mark is set in top of a square concrete post flush with the first
north-south road east of dock, 450 feet (137 m) south of the intersection of
99th Avenue SW and 240th Street SW, 300 feet (91 m) north of beach road, at the
NW corner of an orchard, in front of a house, 18 feet (6 m) east of east edge of
the north-south street, 9 feet (3 m) south of the centerline of a driveway and 3
feet (1 m) south of the south gate post at entrance to yard.
BENCH MARK STAMPING: NO 3 1917
MONUMENTATION: Survey Disk VM#: 9123
AGENCY: PID#: SY0646
SETTING CLASSIFICATION: Concrete Post
The bench mark is set in top of a 1 foot (0.3 m) square concrete post, on
private property, 960 feet (293 m) east of inshore end of the dock, 21.5 feet
(6.6 m) SW of a lone pine tree in center of lawn, 13 feet (4 m) north of the
centerline of Beach Road, 2 feet (1 m) east of fence post at end of fence along
west side of lawn, 2 feet (1 m) north of the north edge of beach road and at
ground level.
BENCH MARK STAMPING: NO 2 1935
MONUMENTATION: Survey Disk VM#: 9124
AGENCY: PID#: SY0645
SETTING CLASSIFICATION: Rock
The bench mark is set in a boulder imbedded in the ground, 60 feet (18 m) east
of the foot of 103 Avenue SW, 45 feet (14 m) east of inner end of yacht club
dock, 40 feet (12 m) SE of a 4-trunk madrona tree and at ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 04/20/1984
Station ID: 9446254 SUPERCEDED DATE: 04/21/2003
Name: BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR
WASHINGTON
NOAA Chart: 18448 Latitude: 47° 23.7' N
USGS Quad: VASHON Longitude: 122° 27.8' W
T I D A L D A T U M S
Tidal datums at BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: FEBRUARY 1975
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 (02/01/1975) = 13.97
MEAN HIGHER HIGH WATER MHHW = 12.05
MEAN HIGH WATER MHW = 11.14
MEAN TIDE LEVEL MTL = 7.01
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 6.40
MEAN LOW WATER MLW = 2.88
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (12/24/1975) = -2.01
* NGVD reference based on adjustment of 1959 and NOS levels of 1/17/75.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
TIDAL 1 1975 11.06 -0.08
TIDAL 2 1975 9.64 -1.50
TIDAL 3 1975 28.54 17.40
TIDAL 4 1975 37.55 26.41
NO 2 1917 27.08 15.94
NO 3 1917 16.09 4.95
NO 2 1935 14.93 3.79
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 04/20/1984
Station ID: 9446254 SUPERCEDED DATE: 04/21/2003
Name: BURTON INSIDE, VASHON ISLAND, QUARTERMASTER HARBOR
WASHINGTON
NOAA Chart: 18448 Latitude: 47° 23.7' N
USGS Quad: VASHON Longitude: 122° 27.8' 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.