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Bench Mark Sheet for 9434938, DRIFT CREEK, ALSEA RIVER

Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 9434938                         PUBLICATION DATE:  05/23/2003
Name:       DRIFT CREEK, ALSEA RIVER                          
            OR
NOAA Chart: 18561                           Latitude:   44° 24.8' N (  44.41330)
USGS Quad:  TIDEWATER                       Longitude: 123° 59.4' W (-123.99000)


To reach the tidal bench marks from the intersection of U.S. Highway 101 and
State Highway 34 in Waldport, proceed east on State Highway 34 for about 8 km (5
mi) to 4015 Highway 34 and Drift Creek Boat Dock on Alsea River.  The bench
marks are located along State Highway 34 at Oakland's Fish Camp and at Bosworths
Boat Repair.  The tide gage and staff were located on the Boat Dock.


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


                 PRIMARY BENCH MARK STAMPING:  4938 B 1976
                         DESIGNATION:          943 4938 B

MONUMENTATION:           Tidal Station disk                    VM#:         8821
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   44° 24.8' N (  44.41330)          LONGITUDE: 123° 59.4' W (-123.99000)


The primary bench mark is a disk located 49 m (162 ft) north of the centerline
of State Highway 34, 30.18 m (99.0 ft) east of bench mark 4938 A 1976, 21.34 m
(70.0 ft) NNW of the NW corner of Bosworths Boat Repair Shop, 0.61 m (2.0 ft)
north of a utility pole, and 0.43 m (1.4 ft) north of a metal witness post.  The
bench mark is set at ground level, crimped to the top of an unspecified steel
rod driven to an unspecified depth, and encased in a 4-inch plastic pipe with a
concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 9434938                         PUBLICATION DATE:  05/23/2003
Name:       DRIFT CREEK, ALSEA RIVER                          
            OR
NOAA Chart: 18561                           Latitude:   44° 24.8' N (  44.41330)
USGS Quad:  TIDEWATER                       Longitude: 123° 59.4' W (-123.99000)


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


                         BENCH MARK STAMPING:  4938 A 1976
                         DESIGNATION:          943 4938 A

MONUMENTATION:           Tidal Station disk                    VM#:         8820
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete boat ramp                    OPUS PID:        
LATITUDE:   44° 24.8' N (  44.41330)          LONGITUDE: 123° 59.4' W (-123.99000)


The bench mark is a disk set flush in concrete at the SW corner of the foot of
the boat ramp at Oakland's Fish Camp, 53 m (174 ft) north of the centerline of
State Highway 34, 8.11 m (26.6 ft) WSW of the SW corner of a house, and 3.23 m
(10.6 ft) SE of the SE corner of Oaklands Marina building.



                         BENCH MARK STAMPING:  4938 C 1976
                         DESIGNATION:          943 4938 C

MONUMENTATION:           Tidal Station disk                    VM#:         8822
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   44° 24.8' N (  44.41330)          LONGITUDE: 123° 59.4' W (-123.99000)


The bench mark is a disk set flush in concrete at the north side of the garage
door on the west side of Bosworths Boat Repair Shop, 29.02 m (95.2 ft) SE of
bench mark 4938 B 1976, and 21.64 m (71.0 ft) north of the centerline of State
Highway 34.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 9434938                         PUBLICATION DATE:  05/23/2003
Name:       DRIFT CREEK, ALSEA RIVER                          
            OR
NOAA Chart: 18561                           Latitude:   44° 24.8' N (  44.41330)
USGS Quad:  TIDEWATER                       Longitude: 123° 59.4' W (-123.99000)


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


                         BENCH MARK STAMPING:  4938 D 1976
                         DESIGNATION:          943 4938 D

MONUMENTATION:           Tidal Station disk                    VM#:         8823
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   44° 24.8' N (  44.41330)          LONGITUDE: 123° 59.4' W (-123.99000)


The bench mark is a disk located 27.13 m (89.0 ft) SW of the SW corner of
Bosworths Boat Repair Shop, 11.13 m (36.5 ft) south of the centerline of State
Highway 34, 3.35 m (11.0 ft) ENE of a utility pole, and 0.30 m (1.0 ft) NE of a
metal witness post.  The bench mark is set 0.03 m (0.1 ft) above ground level,
crimped to the top of an unspecified steel rod driven to an unspecified depth to
refusal, and encased in a 4-inch plastic pipe with a concrete kickblock.



                         BENCH MARK STAMPING:  4938 E 1976
                         DESIGNATION:          943 4938 E

MONUMENTATION:           Tidal Station disk                    VM#:         8824
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Unspecified deep rod                  OPUS PID:        
LATITUDE:   44° 24.8' N (  44.41330)          LONGITUDE: 123° 59.4' W (-123.99000)


The bench mark is a disk located 66 m (216 ft) SW of bench mark 4938 A 1976,
12.19 m (40.0 ft) north of the centerline of State Highway 34, 7.62 m (25.0 ft)
east of a utility pole, and 0.52 m (1.7 ft) SE of a metal witness post.  The
bench mark is set 0.03 m (0.1 ft) above ground level, crimped to the top of an
unspecified steel rod driven an unspecified depth to refusal, and encased in a
4-inch plastic pipe with a concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 9434938                         PUBLICATION DATE:  05/23/2003
Name:       DRIFT CREEK, ALSEA RIVER                          
            OR
NOAA Chart: 18561                           Latitude:   44° 24.8' N (  44.41330)
USGS Quad:  TIDEWATER                       Longitude: 123° 59.4' W (-123.99000)


                            T I D A L   D A T U M S 


Tidal datums at DRIFT CREEK, ALSEA RIVER based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           January 1977 - December 1977
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9432780 CHARLESTON, COOS BAY


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

     HIGHEST OBSERVED WATER LEVEL (01/05/1978)         =  3.272
     MEAN HIGHER HIGH WATER                     MHHW   =  1.966
     MEAN HIGH WATER                            MHW    =  1.756
     MEAN TIDE LEVEL                            MTL    =  0.980
     MEAN SEA LEVEL                             MSL    =  0.902
     MEAN LOW WATER                             MLW    =  0.203
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (07/15/1977)         = -0.337

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4938 B 1976                                 5.695    3.939
     4938 A 1976                                 3.407    1.651
     4938 C 1976                                 5.938    4.182
     4938 D 1976                                 7.442    5.686
     4938 E 1976                                 5.588    3.832


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

                                                                                
Station ID: 9434938                         PUBLICATION DATE:  05/23/2003
Name:       DRIFT CREEK, ALSEA RIVER                          
            OR
NOAA Chart: 18561                           Latitude:   44° 24.8' N (  44.41330)
USGS Quad:  TIDEWATER                       Longitude: 123° 59.4' W (-123.99000)


                             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 9434938 DRIFT CREEK, ALSEA RIVER,

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