NOAA Web Site Link Tides and Currents Home Page Transparent placeholder image

Bench Mark Sheet for 9415193, THREE MILE SLOUGH,SAN JOAQUIN R. 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Superseded Epoch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Small blue map location marker Unpublished bench mark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: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


To reach the tidal bench marks from California Highway 160 turn east on Sherman
Island levee road 4.8 km (3.0 mi) south of the junction of Highways 2 and 160,
continue on the road for 4.8 km (3.0 mi) to Channel Marker No. 1 at the junction
of Three Mile Slough and San Joaquin River.  The tide gage and staff were
located on Channel Marker No. 1.


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


                 PRIMARY BENCH MARK STAMPING:  TIDAL 4 1977
                         DESIGNATION:          941 5193 TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:        11882
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   38°  5.0' N (  38.08330)          LONGITUDE: 121° 41.1' W (-121.68500)


The primary bench mark is a disk located 114.30 m (375.0 ft) NNW of the center
of the T-intersection of the dirt and levee road, 94.49 m (310.0 ft) SSW of
Channel Marker No. 1, 4.57 m (15.0 ft) west of the centerline of the levee road,
and 1.98 m (6.5 ft) north of a witness post.  The bench mark is set  0.18 m (0.6
ft) below road level, set on a copper-clad steel rod, driven 19.20 m (63.0 ft)
to refusal.

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

                                                                                
Station ID: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


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


                         BENCH MARK STAMPING:  SHERMAN 1931 1970
                         DESIGNATION:          SHERMAN RESET

MONUMENTATION:           Tidal Station disk                    VM#:        11884
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  JS1716
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   38°  5.0' N (  38.08330)          LONGITUDE: 121° 41.1' W (-121.68500)


The bench mark is a disk set in top of a concrete post 0.06 m (0.2 ft) above
ground, 34.75 m (114.0 ft) north of the juncton of farm road leading west, 12.25
m (40.2 ft) SE of bench mark SHERMAN NO 2 1931, 5.43 m (17.8 ft) east of the
centerline of levee road, 1.07 m (3.5 ft) WNW of metal pipe 0.15 m (0.5 ft)
above grade, 0.61 m (2.0 ft) west of a metal witness post, and 0.30 m (1.0 ft)
below grade.

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

                                                                                
Station ID: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


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


                         BENCH MARK STAMPING:  SHERMAN NO 2 1931
                         DESIGNATION:          SHERMAN RM 2

MONUMENTATION:           Reference Mark disk                   VM#:        11885
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  JS1717
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   38°  5.0' N (  38.08330)          LONGITUDE: 121° 41.1' W (-121.68500)


The bench mark is a disk set in top of a concrete post 0.06 m (0.2 ft) above
ground, 66.75 m (219.0 ft) north of the center of a triangle formed by the
junction of a driveway leading west, 3.81 m (12.5 ft) west of the centerline of
the levee road, 0.46 m (1.5 ft) south of a witness post, 0.37 m (1.2 ft) east of
a fence and level with the road. 

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

                                                                                
Station ID: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


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


                         BENCH MARK STAMPING:  SHERMAN 1931 NO 3 1970
                         DESIGNATION:          SHERMAN RM 3

MONUMENTATION:           Reference Mark disk                   VM#:        11886
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  JS1719
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   38°  5.0' N (  38.08330)          LONGITUDE: 121° 41.1' W (-121.68500)


The bench mark is a disk set in top of a concrete post flush with the ground,
29.26 m (96.0 ft) north of junction of a farm road leading west, 5.39 m (17.7
ft) south of bench mark SHERMAN 1931 1970, 4.57 m (15.0 ft) east of the
centerline of the levee road, and 0.46 m (1.5 ft) below the road.



                         BENCH MARK STAMPING:  5193 A 1992
                         DESIGNATION:          941 5193 A

MONUMENTATION:           Tidal Station disk                    VM#:        11889
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Drill hole                            OPUS PID#: BBCQ22
LATITUDE:   38°  5.0' N (  38.08330)          LONGITUDE: 121° 41.1' W (-121.68500)


The bench mark is a disk set flush into a drill hole in the SW corner of the
concrete foundation, located on a concrete foundation of a gas main (designated
by a State Lands Commission Mark as PRC NO 74) manhole cover, approximately 2.50
m x 2.50 m (8.2 ft x 8.2 ft),  13.11 m (43.0 ft) WSW of a PG&E gas pipeline
crossing sign on the offshore side of the levee road, 10.06 m (33.0 ft) SE of
PG&E Utility Pole No. GT 96477, 6.10 m (20.0 ft) WSW (shore-side) of the
centerline of the levee road, and 0.15 m (0.5 ft) above the levee road.

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

                                                                                
Station ID: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


                            T I D A L   D A T U M S 


Tidal datums at THREE MILE SLOUGH,SAN JOAQUIN R. based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           July 15,1992 - September 14,1992
     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   =  1.042
     MEAN HIGH WATER                            MHW    =  0.898
     MEAN SEA LEVEL                             MSL    =  0.536
     MEAN TIDE LEVEL                            MTL    =  0.528
     MEAN LOW WATER                             MLW    =  0.159
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     TIDAL 4 1977                                3.667    2.769
     SHERMAN 1931 1970                           3.886    2.988
     SHERMAN NO 2 1931                           4.012    3.114
     SHERMAN 1931 NO 3 1970                      3.939    3.042
     5193 A 1992                                 3.691    2.794


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

                                                                                
Station ID: 9415193                         PUBLICATION DATE:  08/29/2005
Name:       THREE MILE SLOUGH,SAN JOAQUIN R.                  
            CA
NOAA Chart: 18661                           Latitude:   38°  5.2' N (  38.08670)
USGS Quad:  JERSEY ISLAND                   Longitude: 121° 41.1' W (-121.68500)


                             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.

Return to Top
Products available at 9415193 THREE MILE SLOUGH,SAN JOAQUIN R., CA

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