NOAA Web Site Link Tides and Currents Home Page Transparent placeholder image

On Saturday, June 23rd, 2018 starting at 7:30 a.m to 8 p.m. EDT, there will be a system maintenance performed affecting the Tides and Currents web site (https://tidesandcurrents.noaa.gov). During this time, the Tides and Currents website will be running with limited capabilities. Click here for more information.

Bench Mark Sheet for 9411406, Oil Platform Harvest 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 9411406                         PUBLICATION DATE:  11/18/2011
Name:       OIL PLATFORM HARVEST (TOPEX PROJECT)              
            CA
NOAA Chart: 18721                           Latitude:   34° 28.1' N (  34.46830)
USGS Quad:  NONE                            Longitude: 120° 40.4' W (-120.67300)


TO REACH THE TIDE STATION:  NOTE: All directions are referenced to Platform
coordinates.  True north is actually +45 degrees east from Platform north.  The
deck level location for each reference point is included in the name.


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


                 PRIMARY BENCH MARK STAMPING:   
                         DESIGNATION:          941 1406 NO STAMPING 1
                         ALIAS:                +20 LEG

MONUMENTATION:           See descriptive text                  VM#:        12166
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Platform leg                          OPUS PID:        
LATITUDE:   34° 28.1' N (  34.46908)          LONGITUDE: 120° 40.9' W (-120.68189)


The bench mark is the high point of a 2-inch lip of the 1.83 m (6.0 ft) diameter
platform leg where it is welded at a junction, 12.80 m (42.0 ft) west of bench
mark 941 1406 NO STAMPING 2, 12.71 m (41.7 ft) south of the NW corner leg, and
1.43 m (4.7 ft) above the steel floor grating of the +20 Boat Deck.  The lip is
directly above a 16-inch horizontal diagonal pipe which leads to the NE leg of
the platform.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          941 1406 NO STAMPING 2
                         ALIAS:                +20 PIPE EYE

MONUMENTATION:           See descriptive text                  VM#:        12167
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Pipe eye                              OPUS PID:        
LATITUDE:   34° 28.1' N (  34.46908)          LONGITUDE: 120° 40.9' W (-120.68189)


The mark is the highest point of a 7-inch wide eye on top of the eastern-most
pipe protruding up through the second east-west catwalk from the north end of
the platform, about 12 m (40 ft) SSW of the NE main support pile, 5 m (15 ft)
west of the platform east side railing, 1 m (3 ft) south of the north railing of
the catwalk, and 1 m (3 ft) above deck level.  10/93: Top of eye sprayed with
blue spray paint.

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

                                                                                
Station ID: 9411406                         PUBLICATION DATE:  11/18/2011
Name:       OIL PLATFORM HARVEST (TOPEX PROJECT)              
            CA
NOAA Chart: 18721                           Latitude:   34° 28.1' N (  34.46830)
USGS Quad:  NONE                            Longitude: 120° 40.4' W (-120.67300)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          941 1406 NO STAMPING 3
                         ALIAS:                +47 STAIR TOP

MONUMENTATION:           See descriptive text                  VM#:        12168
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Metal stair                           OPUS PID:        
LATITUDE:   34° 28.1' N (  34.46908)          LONGITUDE: 120° 40.9' W (-120.68189)


The mark is a raised weld point at the top junction of the western-most pin eye
at the top of the stairs leading from the +47 deck to the +20 deck, 0.2 m (0.8
ft) south of the southern end of the western railing on the +47 deck, 0.1 m (0.3
ft) east of the SW corner of the +47 deck, and 0.1 m (0.2 ft) NW of the center
of the pin.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          941 1406 NO STAMPING 5
                         ALIAS:                +124 DECK

MONUMENTATION:           See descriptive text                  VM#:        12170
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Deck                                  OPUS PID:        
LATITUDE:   34° 28.1' N (  34.46908)          LONGITUDE: 120° 40.9' W (-120.68189)


The mark is the high point of a notch in the center of a vertical 6x1.5x1/4
channel cableway located near the platform NE corner stairway, 1.5 m (5.0 ft)
south of the first step down the stairway, 1.4 m (4.6 ft) east of the center of
a 1-foot diameter crane boom rest support, 0.2 m (0.7 ft) east of the platform
east side railing, 0.1 m (0.2 ft) north of an alarm station stanchion, and 0.1 m
(0.3 ft) below deck level.  5/92: Painted yellow.

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

                                                                                
Station ID: 9411406                         PUBLICATION DATE:  11/18/2011
Name:       OIL PLATFORM HARVEST (TOPEX PROJECT)              
            CA
NOAA Chart: 18721                           Latitude:   34° 28.1' N (  34.46830)
USGS Quad:  NONE                            Longitude: 120° 40.4' W (-120.67300)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          941 1406 NO STAMPING 6
                         ALIAS:                PENTHOUSE DECK

MONUMENTATION:           See descriptive text                  VM#:        12171
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Deck                                  OPUS PID:        
LATITUDE:   ' °deg (0)          LONGITUDE:  ' °deg (0)




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

                                                                                
Station ID: 9411406                         PUBLICATION DATE:  11/18/2011
Name:       OIL PLATFORM HARVEST (TOPEX PROJECT)              
            CA
NOAA Chart: 18721                           Latitude:   34° 28.1' N (  34.46830)
USGS Quad:  NONE                            Longitude: 120° 40.4' W (-120.67300)


                            T I D A L   D A T U M S 


Tidal datums at OIL PLATFORM HARVEST (TOPEX PROJECT) based on:

     LENGTH OF SERIES:      165 MONTHS
     TIME PERIOD:           November 1996 - July 2010
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9410660 LOS ANGELES, OUTER HARBOR


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

     HIGHEST OBSERVED WATER LEVEL (06/06/1997)         =  2.275
     MEAN HIGHER HIGH WATER                     MHHW   =  1.598
     MEAN HIGH WATER                            MHW    =  1.373
     MEAN TIDE LEVEL                            MTL    =  0.838
     MEAN SEA LEVEL                             MSL    =  0.830
     MEAN LOW WATER                             MLW    =  0.304
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (06/03/1992)         = -0.676

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     941 1406 NO STAMPING 1                      6.486    5.113
     941 1406 NO STAMPING 2                      5.991    4.618
     941 1406 NO STAMPING 3                     13.257   11.884
     941 1406 NO STAMPING 5                     36.599   35.226
     941 1406 NO STAMPING 6                     48.523   47.150


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

                                                                                
Station ID: 9411406                         PUBLICATION DATE:  11/18/2011
Name:       OIL PLATFORM HARVEST (TOPEX PROJECT)              
            CA
NOAA Chart: 18721                           Latitude:   34° 28.1' N (  34.46830)
USGS Quad:  NONE                            Longitude: 120° 40.4' W (-120.67300)


                             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.

Return to Top
Products available at 9411406 Oil Platform Harvest, CA

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services