U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
To reach the tidal bench marks traveling north on Highway 101 from San Rafael,
take the Hamilton part of the Alameda Del Prado exit, turn right on Main Gate
Road, then right on South Palm Drive, then right on Hamilton Parkway. Go right
at traffic circle and take Sunset Drive, then left at stop sign to Las Lomas
Drive and then proceed to traffic circle and take Caliente Real Road. Go right
at bottom of hill and proceed until road gets to edge of slough adjacent to San
Francisco Bay. The bench marks are located in the vicinity along the road
leading to approach lights and also along the road leading to rescue towers.
The tide station is on the wooden pier at the inshore end of the slough.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5126 D 2000
DESIGNATION: 941 5126 D
MONUMENTATION: Flange-encased Rod VM#: 16030
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The primary bench mark is a flanged encased rod mark, set in a grass triangle
area between Casa Grande Real and Las Lomas Drive, located at the U.S. Coast
Guard housing area in San Rafael, 20 m (65 ft) south of the north point of the
triangle, 15.30 m (50.2 ft) west of a fire plug in front of house on 293 Casa
Grande Real, 8 m (27 ft) east of the centerline of Las Lomas Drive. The datum
point is set 7 cm (0.25 ft) below ground, being the top of a stainless steel
rod driven 2.7 m (9 ft) to refusal, and encased with a 5'" logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HAMILTON FIELD 2 1951
DESIGNATION: 941 5126 HAMILTON FIELD 2
MONUMENTATION: Bench Mark disk VM#: 16022
AGENCY: US Army Corps of Engineers (USE) IDB PID#: JT2533
SETTING CLASSIFICATION: Concrete pavement OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a brass disk set in concrete pavement near U.S Coast Guard
housing above Hamilton AFB, 50m (165 ft) ESE down the slope from the Admirals
quarters on Casa Grande street, 31 m (102 ft) from the point, 11 m (35 ft)
above tide flats, and 2 m (8 ft) SE of a lone scrub oak tree.
BENCH MARK STAMPING: STA ONE 1986 67TH ENGR
DESIGNATION: 941 5126 STA ONE 67 ENGR
MONUMENTATION: Bench Mark disk VM#: 16023
AGENCY: US Army Corps of Engineers (USE) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a brass disk set in a 2.45 m x 2.15 m (7.0 ft x 8.0 ft)
concrete pad resting on the remains of Hamilton AFB rescue tower pier, 0.64 km
(0.4 mi) east of the Marin County Sheriff Warehouse Building #82, 53 m (174 ft)
north of east end of cyclone fence, 21 m (69 ft) south of centerline of a road
leading to approach lights, 1.80 m (5.9 ft) west of east face of concrete pad,
1.65m (5.4 ft) north of south edge of pad, and 0.8 m (2.6 ft ) above landing
adjacent to pier.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5126 A 2000
DESIGNATION: 941 5126 A
MONUMENTATION: Tidal Station disk VM#: 16027
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete drain foundation OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a red-brass disk set in the SW corner of a storm drain on
Hamilton AFB north of road leading to rescue tower, 143 m (470 ft) east of the
Marin County Sheriff Warehouse building #82, 9.00 m (29.5 ft) north of
centerline of road, 2.01 m (6.6 ft) SW from NE face, and 0.5 m (1.6 ft) above
ground.
BENCH MARK STAMPING: 5126 B 2000
DESIGNATION: 941 5126 B
MONUMENTATION: Tidal Station disk VM#: 16028
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete culvert OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a red-brass disk set in west elbow of a concrete irrigation
culvert on Hamilton AFB at the corner of Hanger Avenue and the road leading to
the rescue tower, 0.2 km (0.1 mi) west of a cyclone gate, 19 m (62 ft) east of
the centerline of Hanger Avenue, 2.59 m (8.5 ft) east of NE corner of a storm
grate, and 0.3 m (1.0 ft) below grade.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5126 C 2000
DESIGNATION: 941 5126 C
MONUMENTATION: Tidal Station disk VM#: 16029
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete storm drain OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a red-brass disk set in a concrete storm drain on Caliente
Real near Hamilton AFB and U.S. Coast Guard housing area, 108 m (354 ft ) west
of centerline of Hanger Avenue, 90 m (295 ft) east of NE corner of a utility
shed at the top of Caliente Real, 4.21 m (13.8 ft) north of centerline of
Caliente Real, and 0.21 m (0.7 ft) above grade.
BENCH MARK STAMPING: 5126 E 2000
DESIGNATION: 941 5126 E
MONUMENTATION: Flange-encased Rod VM#: 16031
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a flanged encased rod mark located on Hamilton AFB near
rescue tower, 0.8 km (0.5 mi) east of the Marin County Sheriff training
warehouse building # 82, 26 m (85 ft) SE of centerline of a road leading to
approach lights, 25m (82 ft) north of north bank of channel leading to rescue
tower, and 0.70 m (2.3 ft) north of an orange NOS witness post. The datum point
is set 7 cm (0.25 ft) below ground, being the top of a stainless steel rod
driven 28.7 m (94 ft) to refusal, and encased in a 5" logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING:
DESIGNATION: 941 5126 BOLT
ALIAS: ALL THREAD
MONUMENTATION: Bolt VM#: 16032
AGENCY: Unknown IDB PID#:
SETTING CLASSIFICATION: Concrete utility vault OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a 1/2 x 4 inch bolt end, protruding from a concrete utility
vault on the road leading to rescue tower and approach lights at Hamilton AFB,
0.3 km (0.2 mi ) east of the Marin County Sheriff Warehouse building #82, 115 m
(377 ft) west of a fork in road, 16.8 m (55.1 ft) north of centerline of road,
1.31 m (4.3 ft) east of NW face of vault, 1.28 m (4.2 ft) SW of NE face of
vault, 0.49 m (1.6 ft) NE of SW face of vault, and 0.27 m (0.9 ft) above grade.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 5
DESIGNATION: 941 5126 NO 5 USE
ALIAS: 5 USE
MONUMENTATION: Bench Mark disk VM#: 16198
AGENCY: US Army Corps of Engineers (USE) IDB PID#: JT0811
SETTING CLASSIFICATION: Window sill OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a disk set in the window sill at NW face at the NE corner of
Hangar NO 1, at the U.S. Coast Guard station, 40 m (130 ft) WSW of bench mark
T736 1944, 2.10 m (6.9 ft) SW of the NE corner of the Hangar, 0.15 m (0.5 ft) SE
of the NW edge of the window sill, and 0.91 m (3.0 ft) above ground. Note: The
access to Coast Guard base is restricted, contact the USCG Pacific Strike Team
at (415) 883-3311 for access to tide station and bench marks.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: T 736 1944
DESIGNATION: 941 5126 T736
ALIAS: T736
MONUMENTATION: Bench Mark disk VM#: 16199
AGENCY: National Geodetic Survey (NGS) IDB PID#: JT0813
SETTING CLASSIFICATION: Window Sill OPUS PID:
LATITUDE: 38° 2.9' N ( 38.04830) LONGITUDE: 122° 29.9' W (-122.49800)
The bench mark is a disk set in the window sill at the northwest corner of
Hangar NO 1 in the window sill, at the U.S. Coast Guard station, 40 m (130 ft)
WSW of bench mark NO 5, 2.10 m (6.9 ft) NE of the NW corner of the Hangar, 0.15
m (0.5 ft) SE of the NW edge of the window sill, and 0.91 m (3.0 ft) above
ground. Note: The access to Coast Guard base is restricted, contact the USCG
Pacific Strike Team at (415) 883-3311 for access to tide station and painted
bench mark.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
T I D A L D A T U M S
Tidal datums at HAMILTON AIR FORCE BASE INSIDE GAUGE based on:
LENGTH OF SERIES: 1 YEAR
TIME PERIOD: February 2000 - February 2001
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9414863 RICHMOND, CHEVRON OIL PIER
Elevations of tidal datums referred to Mean High Water (MHW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.174
MEAN HIGH WATER MHW = 0.000
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = -0.909
* North American Vertical Datum NAVD88 = -1.725
* The NAVD 88 value was derived through GPS observations performed by the
National Geodetic Survey (NGS). The NGVD 29 value was derived from one
leveled geodetic bench mark.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MHW
5126 D 2000 10.142
HAMILTON FIELD 2 1951 9.793
STA ONE 1986 67TH ENGR 2.218
5126 A 2000 -1.978
5126 B 2000 -1.581
5126 C 2000 6.426
5126 E 2000 0.049
941 5126 BOLT -2.367
NO 5 -0.363
T 736 1944 -0.364
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 9 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
Foot Notes:
Only high water tidal datums were determined for this station as gauge location
prevented collection of full range of tide.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 10 of 10
Station ID: 9415126 PUBLICATION DATE: 01/18/2005
Name: HAMILTON AIR FORCE BASE INSIDE GAUGE
CA
NOAA Chart: 18654 Latitude: 38° 2.9' N ( 38.04830)
USGS Quad: Petaluma Point Longitude: 122° 29.9' W (-122.49800)
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.