U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
To reach the tidal bench marks from Marshall, CA, go 0.3 km (0.2 mi) south of
the post office in Marshall on State Highway 1, pass Marshall Tavern and go to
Tony's Seafood Restaurant Wharf. The bench amrks were located along the State
Highway 1 in the vicinity. The tide gauge was located on the Tony's Seafood
Restaurant Wharf.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5320 A 1994
DESIGNATION: 941 5320 A
MONUMENTATION: Tidal Station disk VM#: 12519
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete culvert head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The primary bench mark is a disk set flush in top of a concrete culvert headwall
at milepost 37.09 on the NE side of U.S. Highway One, SE of Marshall,
California, 10.42 m (34.2 ft) SW of utility pole #272, 4.18 m (13.7 ft) SSE of
center line of U.S. Highway One, 1.62 m (5.3 ft) nw of the milepost 37.09 on NE
side of U.S. Highway One, and 0.06 m (0.2 ft) below road level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5320 B 1994
DESIGNATION: 941 5320 B
MONUMENTATION: Tidal Station disk VM#: 12520
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete culvert head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark Is a disk set flush in a concrete culvert headwall at milepost
37.38 on the NE side of U.S. Highway One, across from the Marshall Boat Works at
Marshall, California, 18.14 m (59.5 ft) SE of the stop sign at the U.S. Post
Office, 5.52 m (18.1 ft) NE of the center line of U.S. Highway One, 1.52 m (5.0
ft) north of milepost 37.38 on NE side of U.S. Highway One, and 0.61 m (2.0 ft)
below road level.
BENCH MARK STAMPING: 5320 C 1994
DESIGNATION: 941 5320 C
MONUMENTATION: Tidal Station disk VM#: 12521
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete culvert head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark is a disk set flush in the top of a concrete culvert headwall at
milepost 37.62 on the NE side of U.S. Highway One at Marshall, California, 27.28
m (89.5 ft) east of utility pole # 289 with transformer, 5.88 m (19.3 ft) NE of
the center line of U.S. Highway One, 0.30 m (1.0 ft) NE of milepost 37.62 on NE
side of U.S. Highway One, and 0.15 m (0.5 ft) NW of the east end of the
headwall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 71 FMK 1975
DESIGNATION: 941 5320 71 FMK
MONUMENTATION: Bench Mark disk VM#: 12522
AGENCY: US Department of Interior (DI) IDB PID#:
SETTING CLASSIFICATION: Concrete head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark is a disk set flush in top of a concrete culvert headwall at
milepost 36.90 on the NE side of U.S. Highway One, SE of Marshall, California,
10.27 m (33.7 ft) south of utility pole # 266 with transformer, 5.03 m (16.5 ft)
NE of the center line of U.S. Highway One, 1.68 m (5.5 ft) north of milepost
36.90, and 0.21 m (0.7 ft) NW of SE end of headwall.
BENCH MARK STAMPING: 76 FMK 1975
DESIGNATION: 941 5320 76 FMK
MONUMENTATION: Bench Mark disk VM#: 12523
AGENCY: US Department of Interior (DI) IDB PID#:
SETTING CLASSIFICATION: Concrete head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark is a disk set flush in top of a concrete culvert headwall at
milepost 37.93 on the NE side of U.S. Highway One in Marshall, California, 35.87
m (117.7 ft) SE of power pole # 298 with tansformer, 5.49 m (18.0 ft) east of
center line of U.S. Highway One, 0.30 m (1.0 ft) north of milepost 37.93 on U.S.
Highway One, and 0.30 m (1.0 ft) above ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 77 FMK 1975
DESIGNATION: 941 5320 77 FMK
MONUMENTATION: Bench Mark disk VM#: 12524
AGENCY: US Department of Interior (DI) IDB PID#:
SETTING CLASSIFICATION: Concrete head wall OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark is a disk set flush in top of a concrete culvert headwall at
milepost 38.03 on the NE side of U.S. Highway One, 11.43 m (37.5 ft) ENE of
utility pole # 300, 4.57 m (15.0 ft) east of the center line of U.S. Highway
One, and 0.61 m (2.0 ft) north of milepost 38.03 on U.S. Highway One.
BENCH MARK STAMPING: NO 1 1931
DESIGNATION: 941 5320 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 13561
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID:
LATITUDE: 38° 8.8' N ( 38.14670) LONGITUDE: 122° 53.0' W (-122.88300)
The bench mark is a disk set in a rock located NW side of the bight forming the
harbor of Marshall, 156 m (513 ft) west of bridge crossing slough, 48 m (157 ft)
NE of the large offlying rock, 6 m (20 ft) south of the old rail road bed, and
about 1 m (2 ft) above the apparent high water line.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
T I D A L D A T U M S
Tidal datums at REYNOLDS, TOMALES BAY based on:
LENGTH OF SERIES: 2 Months
TIME PERIOD: April 1994 - May 1994
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:
MEAN HIGHER HIGH WATER MHHW = 1.649
MEAN HIGH WATER MHW = 1.427
MEAN TIDE LEVEL MTL = 0.859
MEAN SEA LEVEL MSL = 0.838
MEAN LOW WATER MLW = 0.290
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
5320 A 1994 4.023 2.596
5320 B 1994 3.024 1.597
5320 C 1994 3.012 1.585
71 FMK 1975 2.253 0.826
76 FMK 1975 3.567 2.140
77 FMK 1975 3.065 1.638
NO 1 1931 1.937 0.510
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 9415320 PUBLICATION DATE: 04/21/2003
Name: REYNOLDS, TOMALES BAY
CA
NOAA Chart: 18643 Latitude: 38° 8.8' N ( 38.14670)
USGS Quad: Tomales Longitude: 122° 53.0' W (-122.88300)
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.