U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                   PUBLICATION DATE:  01/04/1985
Station ID: 9415498                                SUPERCEDED DATE:   04/21/2003
Name:       SUISUN CITY, SUISUN SLOUGH                        
            CALIFORNIA
NOAA Chart: 18656                                  Latitude:         38° 14.2' N
USGS Quad:  FAIRFIELD                              Longitude:       122°  1.8' W


To reach the tidal bench marks proceed along Marina Boulevard in Suisun City to
the Suisun-Pacific Marina on the Suisun Slough.  The bench marks are located on
the marina property.  The tide gage and staff were located on the seawall at the
marina along Suisun Slough.


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


                 PRIMARY BENCH MARK STAMPING:  5498 B 1977

MONUMENTATION:           Survey Disk                               VM#:     8691
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 53.0 feet (16.2 m) SSW from the third light pole in a row
extending SSW of the harbor master office, 15.5 feet (4.7 m) WNW of the gate
leading to floating deck A, 11.0 feet (3.4 m) SE of a concrete high voltage
utility box cover level with the ground, 3.8 feet (1.2 m) west of marina fire
hydrant No. 500, and 0.1 foot (0.03 m) below the grade.  The bench mark is on a
rod driven 60.0 feet (18.3 m), inside a PVC pipe, and 0.4 foot (0.1 m) below the
top of the PVC pipe.



                         BENCH MARK STAMPING:  5498 B1 1977

MONUMENTATION:           Survey Disk                               VM#:     8692
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Concrete Base


The bench mark is set in a concrete base of a flagpole at the Suisun-Pacific
Marina, in front of the harbor master house, 0.9 foot (0.3 m) east of the
flagpole, and flush with the concrete base.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                   PUBLICATION DATE:  01/04/1985
Station ID: 9415498                                SUPERCEDED DATE:   04/21/2003
Name:       SUISUN CITY, SUISUN SLOUGH                        
            CALIFORNIA
NOAA Chart: 18656                                  Latitude:         38° 14.2' N
USGS Quad:  FAIRFIELD                              Longitude:       122°  1.8' W


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


                         BENCH MARK STAMPING:  5498 C 1977

MONUMENTATION:           Survey Disk                               VM#:     8693
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 91.0 feet (27.7 m) ESE from the east corner of the
southwesternmost of 3 sheds, 45.0 feet (13.7 m) NE from the fourth light/power
pole of a connected series of poles, 16.9 feet (5.2 m) NNW from the center of
the gate leading to floating dock E, and 0.2 foot (0.06 m) below the grade.  The
bench mark is on a rod driven 54.0 feet (16.5 m), inside a PVC pipe, and 0.8
foot (0.2 m) below the top of the PVC pipe.



                         BENCH MARK STAMPING:  5498 D 1977

MONUMENTATION:           Survey Disk                               VM#:     8694
AGENCY:                                                            PID#:  AE7864
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is set in the concrete seawall on the NE side of Suisun-Pacific
Marina boat ramp, 910.0 feet (277.4 m) east from the north corner of the boat
ramp, 16.5 feet (5.0 m) SSE from a lamp post, and flush in the seawall.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                   PUBLICATION DATE:  01/04/1985
Station ID: 9415498                                SUPERCEDED DATE:   04/21/2003
Name:       SUISUN CITY, SUISUN SLOUGH                        
            CALIFORNIA
NOAA Chart: 18656                                  Latitude:         38° 14.2' N
USGS Quad:  FAIRFIELD                              Longitude:       122°  1.8' W


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


                         BENCH MARK STAMPING:  5498 E 1977

MONUMENTATION:           Survey Disk                               VM#:     8695
AGENCY:                                                            PID:         
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 62.5 feet (19.0 m) NE from fire hydrant No. 72 in the
Suisun-Pacific subdivision at the intersection of Marina Circle and Marina
Drive, 50.0 feet (15.2 m) ENE from the center of the intersection of Marina
Circle and Marina Drive, 20.8 feet (6.3 m) SSW from the power pole at the east
corner of Marina Circle and Marina Drive, 2.0 feet (0.6 m) NNE from the Marina
Circle road sign at the entrance to the marina, and 0.1 foot (0.03 m) above the
grade.  The bench mark is on a rod driven to 66.0 feet (20 m), inside a PVC pipe
and 0.6 foot (0.2 m) below the top of the pipe.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                   PUBLICATION DATE:  01/04/1985
Station ID: 9415498                                SUPERCEDED DATE:   04/21/2003
Name:       SUISUN CITY, SUISUN SLOUGH                        
            CALIFORNIA
NOAA Chart: 18656                                  Latitude:         38° 14.2' N
USGS Quad:  FAIRFIELD                              Longitude:       122°  1.8' W


                            T I D A L   D A T U M S 


Tidal datums at SUISUN CITY, SUISUN SLOUGH based on:

     LENGTH OF SERIES:      15 MONTHS
     TIME PERIOD:           APRIL 1977-JUNE 1978
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  9415144 PORT CHICAGO


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:

     HIGHEST OBSERVED WATER LEVEL (01/16/1978)         =   7.00
     MEAN HIGHER HIGH WATER                     MHHW   =   5.15
     MEAN HIGH WATER                            MHW    =   4.67
     MEAN TIDE LEVEL                            MTL    =   2.68
     MEAN LOW WATER                             MLW    =   0.69
     MEAN LOWER LOW WATER                       MLLW   =   0.00
     LOWEST  OBSERVED WATER LEVEL (05/05/1978)         =  -1.03

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In FEET above:

     Stamping or Designation                    MLLW        MHW

     5498 B 1977                                 7.91      3.24
     5498 B1 1977                                8.25      3.58
     5498 C 1977                                 8.23      3.56
     5498 D 1977                                 8.36      3.69
     5498 E 1977                                 4.20     -0.47


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

                                                   PUBLICATION DATE:  01/04/1985
Station ID: 9415498                                SUPERCEDED DATE:   04/21/2003
Name:       SUISUN CITY, SUISUN SLOUGH                        
            CALIFORNIA
NOAA Chart: 18656                                  Latitude:         38° 14.2' N
USGS Quad:  FAIRFIELD                              Longitude:       122°  1.8' 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 (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 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.