U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 9414837 PUBLICATION DATE: 03/09/2004
Name: POINT CHAUNCEY, RICHARDSON BAY
CALIFORNIA
NOAA Chart: 18649 Latitude: 37° 53.5' N
USGS Quad: SAN QUENTIN Longitude: 122° 26.6' W
To reach the tidal bench marks proceed north along U.S. Highway 101 through
Sausalito, over Richardson Bay Bridge, right at clover leaf intersection to
Route 131, left after crossing Northwestern Pacific railroad tracks, and then
south along Paradise Drive to Point Chaunrey. The tide gage and staff were
located on the inside of the L-shaped NOAA Southwest Marine Fisheries Pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 11 1946
DESIGNATION: TIDAL 11 1946
MONUMENTATION: Tidal Station disk VM#: 8442
AGENCY: US Coast and Geodetic Survey (USC&GS) PID#: HT1059
SETTING CLASSIFICATION: Concrete coping
The bench mark is a disk set in top of the concrete coping forming the door
entrance to the machine and electric shop of the U.S. Naval Net Depot, at the
south corner of the shop, 33.53 m (110.0 ft) north of bench mark 10 1937, 2.07 m
(6.8 ft) west of the center of the westernmost of a group of doorways, 0.21 m
(0.7 ft) south of the SW corner of the building, and 0.18 m (0.6 ft) above the
ground.
BENCH MARK STAMPING: 10 1937
DESIGNATION: TIDAL 10 1937
MONUMENTATION: Tidal Station disk VM#: 8441
AGENCY: US Coast and Geodetic Survey (USC&GS) PID#: HT1060
SETTING CLASSIFICATION: Concrete shelf
The bench mark is a disk set on a low narrow concrete shelf on the NE side of
the large abandoned gantry crane track support on the California Nautical School
ground, 55 m (160 ft) SE of the Administration Building, 33.74 m (110.7 ft)
south of the SW corner of building # 21, 8.63 m (28.3 ft) south of the north end
the gantry crane, 0.46 m (1.5 ft) north of the north face of a concrete column,
and 1.01 m (3.3 ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 9414837 PUBLICATION DATE: 03/09/2004
Name: POINT CHAUNCEY, RICHARDSON BAY
CALIFORNIA
NOAA Chart: 18649 Latitude: 37° 53.5' N
USGS Quad: SAN QUENTIN Longitude: 122° 26.6' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 12 1946
DESIGNATION: TIDAL 12 1946
MONUMENTATION: Tidal Station disk VM#: 8443
AGENCY: US Coast and Geodetic Survey (USC&GS) PID#: HT1061
SETTING CLASSIFICATION: Concrete floor
The bench mark is a disk set in the concrete floor of the main entrance to the
south warehouse at the US Naval Net Depot, 237.74 m (780 ft) south of the
Administration Building, 2.26 m (7.4 ft) south of the approximate center of the
main entrance to the building, 0.21 m (0.7 ft) NW of the NW face of the steel
column of the door support, and 0.18 m (0.6 ft) NE of the NE side of the steel
door runner.
BENCH MARK STAMPING: CO RD 1975
DESIGNATION: 941 4837 CO RD 1975
MONUMENTATION: Survey disk VM#: 8444
AGENCY: US Army Corps of Engineers (USE) PID:
SETTING CLASSIFICATION: Concrete monument
The bench mark is a disk set horizontally in a concrete monument, 20 m (65 ft)
east of a power pole, 8 m (27 ft) north of bench mark 10 1937, and 0.15 m (0.5
ft) north of the NE corner of the concrete column at the northermost and of a
large abandoned gantry crane track support.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 9414837 PUBLICATION DATE: 03/09/2004
Name: POINT CHAUNCEY, RICHARDSON BAY
CALIFORNIA
NOAA Chart: 18649 Latitude: 37° 53.5' N
USGS Quad: SAN QUENTIN Longitude: 122° 26.6' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NET HYDRO
DESIGNATION: 941 4837 NET HYDRO
MONUMENTATION: Survey disk VM#: 12525
AGENCY: US Army Corps of Engineers (USE) PID:
SETTING CLASSIFICATION: Concrete sea wall
The bench mark is a disk set in the top of the concrete seawall, 50 m (163 ft)
NW of the NW corner of the L-shaped curbing along the edge of the paved area,
and 46 m (152 ft) SE of the NW corner of the sea wall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 9414837 PUBLICATION DATE: 03/09/2004
Name: POINT CHAUNCEY, RICHARDSON BAY
CALIFORNIA
NOAA Chart: 18649 Latitude: 37° 53.5' N
USGS Quad: SAN QUENTIN Longitude: 122° 26.6' W
T I D A L D A T U M S
Tidal datums at POINT CHAUNCEY, RICHARDSON BAY based on:
LENGTH OF SERIES: 5 MONTHS
TIME PERIOD: March 1993 - July 1993
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9414290 SAN FRANCISCO, SAN FRANCISCO BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER (MHHW) = 1.754
MEAN HIGH WATER (MHW) = 1.573
MEAN TIDE LEVEL (MTL) = 0.953
MEAN SEA LEVEL (MSL) = 0.933
MEAN LOW WATER (MLW) = 0.333
MEAN LOWER LOW WATER (MLLW) = 0.000
National Geodetic Vertical Datum (NGVD 29)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
11 1946 4.662 3.089
10 1937 4.784 3.211
12 1946 5.007 3.434
CO RD 1975 3.917 2.344
NET HYDRO 3.262 1.689
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 9414837 PUBLICATION DATE: 03/09/2004
Name: POINT CHAUNCEY, RICHARDSON BAY
CALIFORNIA
NOAA Chart: 18649 Latitude: 37° 53.5' N
USGS Quad: SAN QUENTIN Longitude: 122° 26.6' 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 (NAVD 88).
NGVD 29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD 29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD 29 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 NGVD 29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD 88 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. NAVD 88 replaces NGVD 29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD 88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD 29 and NAVD 88 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 NAVD 88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD 88 elevations.
The NAVD 88 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, NAVD 88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD 88 elevations listed for
each bench mark in the NGS database.