U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 9415316 PUBLICATION DATE: 09/05/2003
Name: RIO VISTA, SACRAMENTO RIVER
CA
NOAA Chart: 18661 Latitude: 38° 8.7' N ( 38.14500)
USGS Quad: RIO VISTA Longitude: 121° 41.5' W (-121.69200)
To reach the tidal bench marks from State Highway 12, exit southwest on Main
Street, then take a right on Second Street and follow signs to the Coast Guard
Base. The tidal bench marks are located on and near the Base. The tide gauge
was located on the Finger Pier of the Marine Railway at the north end of the
Base.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: A 904 1957
DESIGNATION: A 904
MONUMENTATION: Bench Mark disk VM#: 11925
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: JS1921
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 38° 8.7' N ( 38.14500) LONGITUDE: 121° 41.6' W (-121.69300)
The bench mark is a disk set in the concrete sidewalk on the north side of C.
Wasak Warehouse on the abandoned Rio Vista Army base, 3.90 m (12.8 ft) east of
the east side of the sliding door on the north face of the building, 0.30 (1 ft)
north of the north wall, and set at the ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 9415316 PUBLICATION DATE: 09/05/2003
Name: RIO VISTA, SACRAMENTO RIVER
CA
NOAA Chart: 18661 Latitude: 38° 8.7' N ( 38.14500)
USGS Quad: RIO VISTA Longitude: 121° 41.5' W (-121.69200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: PRC 149
DESIGNATION: PRC 149
MONUMENTATION: Bench Mark disk VM#: 11927
AGENCY: California State Lands Commission IDB PID#:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 38° 8.6' N ( 38.14330) LONGITUDE: 121° 41.6' W (-121.69300)
The bench mark is a disk set on a 10" concrete monument underneath a large sign
marking P.E. & E pipeline crossing, 21.64 m (71.0 ft) west of the edge of the
embankment, 5.64 m (18.5 ft) north of a chainlink fence which is north of the
marine railway, and 0.30 m (1 ft) above grade,
BENCH MARK STAMPING: 5316 A 1996
DESIGNATION: 941 5316 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 13128
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete footing OPUS PID:
LATITUDE: 38° 8.6' N ( 38.14330) LONGITUDE: 121° 41.6' W (-121.69300)
The bench mark is a disk located on Rio Vista Coast Guard Base in the foundation
for a met tower on the north side of the main building, 4.88 m (16.0 ft) NE of
the NW corner of the building, 1.52 m (5.0 ft) NW of the NE corner of the
building, and 0.61 m (2.0 ft) south of the south curb of the road along the
north side of the building.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 9415316 PUBLICATION DATE: 09/05/2003
Name: RIO VISTA, SACRAMENTO RIVER
CA
NOAA Chart: 18661 Latitude: 38° 8.7' N ( 38.14500)
USGS Quad: RIO VISTA Longitude: 121° 41.5' W (-121.69200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5316 B 1996
DESIGNATION: 941 5316 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 13129
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID#: BBCQ24
LATITUDE: 38° 8.6' N ( 38.14330) LONGITUDE: 121° 41.6' W (-121.69300)
The bench mark is a disk set in a 3.05 m x 4.57 m (10.0 ft x 15.0 ft) concrete
pad for a gasoline tank on the Rio Vista Coast guard base, 4.57 m (15.0 ft)
south of the NE corner of the pad, 3.05 m (10.0 ft) east of the SW corner of the
pad, and 1.83 m (6.0 ft) north of the north side of the road leading to the
pier.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 9415316 PUBLICATION DATE: 09/05/2003
Name: RIO VISTA, SACRAMENTO RIVER
CA
NOAA Chart: 18661 Latitude: 38° 8.7' N ( 38.14500)
USGS Quad: RIO VISTA Longitude: 121° 41.5' W (-121.69200)
T I D A L D A T U M S
Tidal datums at RIO VISTA, SACRAMENTO RIVER based on:
LENGTH OF SERIES: 5 MONTHS
TIME PERIOD: August 1996 - December 1996
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9415144 PORT CHICAGO, SUISUN BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.243
MEAN HIGH WATER MHW = 1.098
MEAN SEA LEVEL MSL = 0.649
MEAN TIDE LEVEL MTL = 0.639
MEAN LOW WATER MLW = 0.179
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
A 904 1957 4.477 3.379
PRC 149 7.789 6.691
5316 A 1996 7.867 6.769
5316 B 1996 7.301 6.203
Foot Notes:
CAUTION: Tidal datums at Rio Vista may be subject to change over time due to
land subsidence.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 9415316 PUBLICATION DATE: 09/05/2003
Name: RIO VISTA, SACRAMENTO RIVER
CA
NOAA Chart: 18661 Latitude: 38° 8.7' N ( 38.14500)
USGS Quad: RIO VISTA Longitude: 121° 41.5' W (-121.69200)
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.