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Bench Mark Sheet for 9414958, Bolinas, Bolinas Lagoon 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' W


To reach the tidal bench marks from US Highway 101travel NW to Stinson Beach,
turn west onto Calle Del Arroyo, Continue NW approximately 300 meters until you
reach the security gate for the Seadrift Community, pass throught the gate and
veer right on Seadrift Road, travel approximately 0.3 miles to the community
recreation center on the right side of the road, near the tennis courts.  The
tide gauge is located behind the building housing the bathrooms.  The bench
marks are located along the sea wall, near the end of Seadrift Road, and in the
town of Bolinas.


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


                 PRIMARY BENCH MARK STAMPING:  4958 F 2009
                         DESIGNATION:          941 4958 F

MONUMENTATION:           Tidal Station disk                        VM#:    19225
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The primary bench mark is a metal rod set 41.50 m (136.2 ft) west of the SW
corner of tennis court "3", 30.70 m (100.7 ft) NW of the north corner of a fence
located at 358 Seadrift Road, and 12.25 m (40.2 ft) south of the southern most
gate post marking a sand road leading to the Bolinas Channel. The datum point is
the top of  a stainless steel deep rod driven 15.1 m (49.7 ft)  to refusal and
encased in a 6" PVC in a concrete kick block.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' W


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


                         BENCH MARK STAMPING:  4958 B 1979
                         DESIGNATION:          941 4958 B

MONUMENTATION:           Tidal Station disk                        VM#:    11857
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Concrete sea wall


The bench mark is a disk set in top of a concrete seawall, 4.00 m (13.1 ft) ENE
of the centerline of Wharf Road, 2.74 m (9.0 ft) NW of the NW corner of the
garage at 95 Wharf Road, and 1.22 m (4.0 ft) NNW of the south end of the
seawall.



                         BENCH MARK STAMPING:  4958 C 1979
                         DESIGNATION:          941 4958 C

MONUMENTATION:           Tidal Station disk                        VM#:    11858
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Concrete sea wall


The bench mark is a disk set in top of a concrete seawall, 33.00 m (108.3 ft)
SSE of the SW corner of the last house on Wharf Road, 12.00 m (39.4 ft) NNW of
the south end of the seawall (south end of Wharf Road), and 4.57 m (15.0 ft) ENE
of the centerline of Wharf Road.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' W


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


                         BENCH MARK STAMPING:  4958 G 2009
                         DESIGNATION:          941 4958 G

MONUMENTATION:           Tidal Station disk                        VM#:    19226
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Sea wall


The bench mark is a disk set in centerline on top of a concrete seawall along
the lagoon basin a top of sheet-pile, 24.50 m (80.4 ft) NW of a flag pole
located on the east side of the Seadrift Association bath house, 14.20 m (46.6
ft) north of the NW corner of a of the Seadrift Association bath house, and 5.66
m (18.6 ft) NE of the west corner end of the seawall.



                         BENCH MARK STAMPING:  4958 H 2009
                         DESIGNATION:          941 4958 H

MONUMENTATION:           Tidal Station disk                        VM#:    19227
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Sea wall


The bench mark is set in centerline on top of a concrete seawall along the
lagoon basin a top of sheet-pile, 30.45 m (99.9 ft) NE of a flagpole located on
the east side of the Seadrift Association bath house, 14.29 m (32.8 ft) west of
the inside corner of a bend in the concrete cap, and 3.3 m (10.8 ft) north of
the NE corner of a 10 ft by 8 ft concrete slab located south of cap .

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' W


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


                         BENCH MARK STAMPING:  4958 J 2009
                         DESIGNATION:          941 4958 J

MONUMENTATION:           Tidal Station disk                        VM#:    19228
AGENCY:                  National Ocean Service (NOS)              PID:         
SETTING CLASSIFICATION:  Concrete sea wall


The bench mark is a disk set in centerline on top of a concrete seawall along
the lagoon basin a top of sheet-pile, 12.8 m west of the property line between
345 Seadrift and 347 (vacant lot) Seadrift Avenue, 10.00 m (32.8 ft) east of the
property line between 345 Seadrift and 347 (vacant lot) Seadrift Avenue, and
0.52 m (1.7 ft) south of north edge of a concrete cap of the seawall of the
lagoon,.



                         BENCH MARK STAMPING:  4958 K 2013
                         DESIGNATION:          941 4958 K

MONUMENTATION:           Tidal Station disk                        VM#:    20643
AGENCY:                  National Ocean Service (NOS)              PID:         
SETTING CLASSIFICATION:  Concrete foundation


The bench mark is a disk set in top of a concrete foundation for the fence
around the tennis court at Seadrift community beach, located at base of fourth
fence post north of SE corner of court, 26.73 m (87.7 ft) WNW of a yellow fire
hydrant at entrance to parking area, 24.33 m (79.8 ft) south of the NE corner of
tennis court, 12.40 m (40.7 ft) north of the SE corner of court, 0.20 m (0.7 ft)
east of east edge of court.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' W


                            T I D A L   D A T U M S 


Tidal datums at BOLINAS, BOLINAS LAGOON based on:

     LENGTH OF SERIES:      3 YEARS
     TIME PERIOD:           July 2009 - June 2011 and Nov. 2012 - Oct. 2013
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9415020 POINT REYES, DRAKES BAY


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

     HIGHEST OBSERVED WATER LEVEL (03/20/2011)         =  2.135
     MEAN HIGHER HIGH WATER                     MHHW   =  1.341
     MEAN HIGH WATER                            MHW    =  1.156
     MEAN SEA LEVEL                             MSL    =  0.708
     MEAN TIDE LEVEL                            MTL    =  0.698
     MEAN LOW WATER                             MLW    =  0.241
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (06/07/2012)         = -0.331



Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4958 F 2009                                 4.144    2.988
     4958 B 1979                                 3.680    2.524
     4958 C 1979                                 4.411    3.255
     4958 G 2009                                 2.779    1.623
     4958 H 2009                                 2.770    1.614
     4958 J 2009                                 2.745    1.589
     4958 K 2013                                 3.217    2.061


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

                                                                                
Station ID: 9414958                                PUBLICATION DATE:  02/05/2014
Name:       BOLINAS, BOLINAS LAGOON                           
            CA
NOAA Chart: 18649                                  Latitude:         37° 54.5' N
USGS Quad:  BOLINAS                                Longitude:       122° 40.7' 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.

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Products available at 9414958 Bolinas, Bolinas Lagoon, CA

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