U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 12/22/1982
Station ID: 9432864 SUPERCEDED DATE: 04/21/2003
Name: EMPIRE, COOS BAY
OREGON
NOAA Chart: 18587 Latitude: 43° 23.6' N
USGS Quad: EMPIRE Longitude: 124° 16.8' W
To reach the tidal bench marks from the post office in Empire proceed west along
Newmark Street to Mill Street and Coos Bay. The tide gage and staff were
located on the Empire Fuel Company Dock.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 10 1924
MONUMENTATION: Survey Disk VM#: 8799
AGENCY: PID#: OA0513
SETTING CLASSIFICATION: Concrete Post
The bench mark is located at SE corner of the intersection of Newmark and Mill
Streets, 97.0 feet (29.6 m) east of the NE corner of the US Engineer Yard (on
slope of northwest point of bluff), 67.0 feet (20.4 m) east of the centerline of
Mill Street, 34.0 feet (10.4 m) south of the centerline of Newmark Street, 2.0
feet (0.6 m) south of north boundary fence (extended) of US Engineer Yard, and
2.0 feet (0.6 m) SE of white marker post. The bench mark is set in a 10 inches
square concrete post with a 2-inch by 4-inch indentation at each corner, 3 feet
(0.9 m) deep and projecting 0.25 feet (0.08 m) above ground.
BENCH MARK STAMPING: EMPIRE TIDAL NO 3 1976
MONUMENTATION: Survey Disk VM#: 8797
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Boat Ramp
The bench mark is located at west end of Holland Street, west of intersection of
Mill and Holland Streets and in NE corner of concrete boat ramp at end of
Holland Street.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 12/22/1982
Station ID: 9432864 SUPERCEDED DATE: 04/21/2003
Name: EMPIRE, COOS BAY
OREGON
NOAA Chart: 18587 Latitude: 43° 23.6' N
USGS Quad: EMPIRE Longitude: 124° 16.8' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9 1924
MONUMENTATION: Survey Disk VM#: 8798
AGENCY: PID#: OA0514
SETTING CLASSIFICATION: Concrete Post
The bench mark is located in NE corner of US Engineer yard at the foot of
Newmark Street, 42.5 feet (13.0 m) north of the edge of a concrete driveway,
42.0 feet (12.8 m) west of the eastern boundary fence of the yard, 10 feet (3 m)
south of the northern boundary fence, and 2.0 feet (0.6 m) east of a 4-inch
square marker post. The bench mark is set in a concrete post 10 inch square
concrete post with a 2-inch by 4-inch indentation at each corner, 3 feet (0.9 m)
deep, and the top 4-inches are below the surface of the lawn.
BENCH MARK STAMPING: EMPIRE NORTH BASE 1945
MONUMENTATION: Survey Disk VM#: 8800
AGENCY: PID#: OA0632
SETTING CLASSIFICATION: Unknown
The bench mark is located at the west end of Michigan Avenue, west of
intersection of Michigan Avenue and Mill Street, 40.0 feet (12.2 m) south of
Michigan Avenue and 20.0 feet (6.1 m) east of a high bank.
BENCH MARK STAMPING: COOS BAY RGE L-B
MONUMENTATION: Survey Disk VM#: 8801
AGENCY: PID:
SETTING CLASSIFICATION: Unknown
The bench mark is located at west end of Michigan Avenue, west of intersection
of Michigan Avenue and Mill Street, 21.0 feet (6.4 m) south of centerline of
roadway and 5.0 feet (1.5 m) east of a high bank.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 12/22/1982
Station ID: 9432864 SUPERCEDED DATE: 04/21/2003
Name: EMPIRE, COOS BAY
OREGON
NOAA Chart: 18587 Latitude: 43° 23.6' N
USGS Quad: EMPIRE Longitude: 124° 16.8' W
T I D A L D A T U M S
Tidal datums at EMPIRE, COOS BAY based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: NOVEMBER - DECEMBER 1976
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 9432780 CHARLESTON
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (10/24/1976) = 9.44
MEAN HIGHER HIGH WATER MHHW = 7.66
MEAN HIGH WATER MHW = 7.00
MEAN TIDE LEVEL MTL = 4.14
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 4.08
MEAN LOW WATER MLW = 1.28
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (11/21/1976) = -1.80
* NGVD reference based on adjustment of 1965 and NOS levels of 1976.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
10 1924 23.89 16.89
EMPIRE TIDAL NO 3 1976 10.53 3.53
9 1924 13.24 6.24
EMPIRE NORTH BASE 1945 12.77 5.77
COOS BAY RGE L-B 12.99 5.99
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 12/22/1982
Station ID: 9432864 SUPERCEDED DATE: 04/21/2003
Name: EMPIRE, COOS BAY
OREGON
NOAA Chart: 18587 Latitude: 43° 23.6' N
USGS Quad: EMPIRE Longitude: 124° 16.8' 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.