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Bench Mark Sheet for 9418739, RED BLUFF, HUMBOLDT BAY CA

Superseded Epoch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Small blue map location marker Unpublished bench mark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  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


To reach the tidal bench marks from Eureka, proceed south on U.S. Highway 101
for 9.7 km (6.0 mi) to the King Salmon Avenue exit, then proceed west on King
Salmon Avenue to King Salmon Slough.  The bench marks are located off King
Salmon Road near King Salmon Slough.  The tide gage and staff were located on
Humboldt County Bridge 4C 230 over King Salmon Slough.


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


                 PRIMARY BENCH MARK STAMPING:  8739 B 1978
                         DESIGNATION:          941 8739 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8717
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  LV0653
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID#: LV0653
LATITUDE:   40° 43.5' N (  40.72500)          LONGITUDE: 124° 13.0' W (-124.21631)


The primary bench mark is a disk located 28.35 m (93.0 ft) south of the south
end of bridge 4C 230 along King Salmon Road, 10.1 m (33.0 ft) WSW of the
centerline of King Salmon Road, and 3.0 m (10.0 ft) NNW of the centerline of a
dirt road.  The bench mark is set 6 cm (0.2 ft) below ground level, crimped to
the top of a galvanized steel rod driven 15.5 m (51 ft), and encased in concrete
and a PVC pipe extending 0.21 m (0.7 ft) above grade.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


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


                         BENCH MARK STAMPING:  8739 C 1978
                         DESIGNATION:          941 8739 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8718
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  LV0652
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   40° 44.2' N (  40.73714)          LONGITUDE: 124° 12.7' W (-124.21158)


The bench mark is a disk located 29.0 m (95.0 ft) west of a wooden P.G. and E
Humboldt Power Plant sign, 13.50 m (44.3 ft) NW of the centerline of a private
paved road, and 11.49 m (37.7 ft) SW of the centerline of King Salmon Road.  The
bench mark is set 6 cm (0.2 ft) below ground level, crimped to the top of a
galvanized steel rod driven 14.6 m (48 ft), and encased in concrete and a PVC
pipe extending 0.15 m (0.5 ft) above grade.



                         BENCH MARK STAMPING:  8739 D 1978
                         DESIGNATION:          941 8739 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8719
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   40° 44.3' N (  40.73830)          LONGITUDE: 124° 12.7' W (-124.21200)


The bench mark is a disk located 16.76 m (55.0 ft) south of the centerline of
King Salmon Road, 11.89 m (39.0 ft) west of the centerline of the southbound
entrance ramp to U.S. Highway 101 at King Salmon Road, and 4.88 m (16.0 ft)
south of freeway entrance sign.  The bench mark is set 6 cm (0.2 ft) below
ground level, crimped to a galvanized steel rod driven 9.4 m (31 ft), and
encased in concrete and a PVC pipe.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


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


                         BENCH MARK STAMPING:  P 1087 1967
                         DESIGNATION:          P 1087

MONUMENTATION:           Bench Mark disk                       VM#:         8720
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LV0263
SETTING CLASSIFICATION:  Concrete guardrail                    OPUS PID:        
LATITUDE:   40° 43.5' N (  40.72472)          LONGITUDE: 124° 12.9' W (-124.21489)


The bench mark is a disk set in top of the east concrete guard rail of the
Orchard Avenue overpass No. 4.122 at U.S. Highway 101 mileage post 72.03, 5.49 m
(18.0 ft) east of the centerline of the east lanes of the highway, 1.07 m (3.5
ft) above the highway, and 0.30 m (1.0 ft) north of the south end of the east
guard rail of Orchard Avenue overpass 4.122.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


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


                         BENCH MARK STAMPING:  Q 1087 1967
                         DESIGNATION:          Q 1087

MONUMENTATION:           Bench Mark disk                       VM#:         8721
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LV0264
SETTING CLASSIFICATION:  Concrete guardrail                    OPUS PID:        
LATITUDE:   40° 44.2' N (  40.73592)          LONGITUDE: 124° 12.6' W (-124.21042)


The bench mark is a disk set in the top of the SW end of the SE concrete
guardrail of King Salmon Avenue underpass No. 4-67R at U.S. Highway 101 mileage
post 72.88, 6.10 m (20.0 ft) SE of the centerline of the SE lanes of the
highway, and 1.07 m (3.5 ft) above the highway.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


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


                         BENCH MARK STAMPING:  R 1087 1967
                         DESIGNATION:          R 1087

MONUMENTATION:           Bench Mark disk                       VM#:         8722
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LV0266
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID:        
LATITUDE:   40° 44.7' N (  40.74500)          LONGITUDE: 124° 11.8' W (-124.19700)


The bench mark is a disk set vertically in the SW face of the SW concrete pier
supporting Spruce Point Overpass No. 4.71 at U.S. Highway 101 mileage post 73.72
between the lanes of the highway, 11.28 m (37.0 ft) NW of the centerline of the
SE lanes, 10.06 m (33.0 ft) SE of the centerline of the NW lanes, and 1.07 m
(3.5 ft) above the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


                            T I D A L   D A T U M S 


Tidal datums at RED BLUFF, HUMBOLDT BAY based on:

     LENGTH OF SERIES:      6 MONTHS
     TIME PERIOD:           May 1978 - October 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9419750 CRESCENT CITY, PACIFIC OCEAN


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

     MEAN HIGHER HIGH WATER                     MHHW   =  2.052
     MEAN HIGH WATER                            MHW    =  1.837
     MEAN SEA LEVEL                             MSL    =  1.109
     MEAN TIDE LEVEL                            MTL    =  1.105
     MEAN LOW WATER                             MLW    =  0.372
     North American Vertical Datum              NAVD88 =  0.160
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     8739 B 1978                                 2.743    0.906
     8739 C 1978                                 2.929    1.092
     8739 D 1978                                 2.811    0.974
     P 1087 1967                                10.952    9.115
     Q 1087 1967                                 9.926    8.089
     R 1087 1967                                 5.284    3.447


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

                                                                                
Station ID: 9418739                         PUBLICATION DATE:  02/26/2004
Name:       RED BLUFF, HUMBOLDT BAY                           
            CA
NOAA Chart: 18622                           Latitude:   40° 44.4' N (  40.74000)
USGS Quad:  FIELDS LANDING                  Longitude: 124° 12.7' W (-124.21200)


                             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 9418739 RED BLUFF, HUMBOLDT BAY, CA

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