U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


To reach the tidal bench marks proceed NE along Harrison Street to the
Embarcadero and San Francisco City Firehouse.  The bench marks are in the
vicinity of the pier, on the Embacadero and along Harrison Street.  The tide
gage and staff were located on the west side of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  179 1925
                         DESIGNATION:          941 4317 TIDAL 179

MONUMENTATION:           Tidal Station disk                    VM#:         8094
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HT0759
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   37° 47.4' N (  37.79000)          LONGITUDE: 122° 23.3' W (-122.38800)


The primary bench mark is a disk set vertically in the NW concrete wall of the
San Francisco Fire Department Engine House (Building No. 9), 0.24 m (0.8 ft) NE
of the west corner of the building, and 0.18 m (0.6 ft) above the street.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


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


                         BENCH MARK STAMPING:  TIDAL BM NO 1 1974
                         DESIGNATION:          941 4317 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         8093
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Factory floor                         OPUS PID:        
LATITUDE:   37° 47.4' N (  37.79000)          LONGITUDE: 122° 23.2' W (-122.38700)


The bench mark is a disk set in the floor of a small alcove in the Joseph Magnin
Factory located on the SE side of Harrison Street between Spear and Steuart
Streets, 20 m (66 ft) SW of the north corner of the building, 13 m (42 ft) SE of
the centerline of Harrison Street, 0.21 m (0.7 ft) SW of the NE end of the
alcove, 1.19 m (3.9 ft) above street level, and 0.06 m (0.2 ft) above the
sidewalk.      

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


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


                         BENCH MARK STAMPING:  DD 109 1932
                         DESIGNATION:          DD 109

MONUMENTATION:           Bench Mark disk                       VM#:         8095
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HT0758
SETTING CLASSIFICATION:  Retaining wall                        OPUS PID:        
LATITUDE:   37° 47.3' N (  37.78830)          LONGITUDE: 122° 23.4' W (-122.39000)


The bench mark is a disk set in the top of the NW corner of the concrete
retaining wall of the Atchison, Tepeka, and Santa Fe Railway yards, at the SE
corner of of the intersection of Main and Harrison Streets, 4.33 m (14.2 ft)
east of the east curb of Main Street, 2.50 m (8.2 ft) south of the south curb of
Harrison Street, and level with the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


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


                         BENCH MARK STAMPING:  M 329 12.077
                         DESIGNATION:          M 329

MONUMENTATION:           Bench Mark disk                       VM#:         8096
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HT0787
SETTING CLASSIFICATION:  Pillar of pier                        OPUS PID:        
LATITUDE:   37° 47.3' N (  37.78830)          LONGITUDE: 122° 23.3' W (-122.38800)


The bench mark is a disk set vertically in the NE face of the NW pillar of the
first pier NE of the cable anchor pier of the Oakland Bay Bridge located on the
Embaracadero directly across from Pier 26, 3.11 m (10.2 ft) SE of the north
corner of the pier and 1 m (2 ft) above the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


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


                         BENCH MARK STAMPING:  V 813 1952
                         DESIGNATION:          V 813

MONUMENTATION:           Bench Mark disk                       VM#:         8097
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HT0788
SETTING CLASSIFICATION:  Pillar of pier                        OPUS PID:        
LATITUDE:   37° 47.3' N (  37.78830)          LONGITUDE: 122° 23.3' W (-122.38800)


The bench mark is a disk set vertically in the NW face of the SE pillar of the
first pier NE of the cable anchor pier of Oakland Bay Bridge, on the
Embarrcadero directly across from Pier 26, 9.30 m (30.5 ft) west of the west
rail of the Southern Pacific Company railroad track, 0.24 m (0.8 ft) SW of the
north corner of the pillar, and 0.79 m (2.6 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


                            T I D A L   D A T U M S 


Tidal datums at PIER 22 1/2, SAN FRANCISCO based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           October 1978 - October 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9414290 SAN FRANCISCO, SAN FRANCISCO BAY


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.908
     MEAN HIGH WATER                            MHW    =  1.717
     MEAN TIDE LEVEL                            MTL    =  1.029
     MEAN SEA LEVEL                             MSL    =  0.995
     MEAN LOW WATER                             MLW    =  0.341
     North American Vertical Datum              NAVD88 =  0.006
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     179 1925                                    3.516    1.799
     TIDAL BM NO 1 1974                          4.915    3.198
     DD 109 1932                                 9.680    7.963
     M 329 12.077                                4.520    2.803
     V 813 1952                                  4.355    2.638


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 9414317                         PUBLICATION DATE:  03/09/2004
Name:       PIER 22 1/2, SAN FRANCISCO                        
            CA
NOAA Chart: 18649                           Latitude:   37° 47.4' N (  37.79000)
USGS Quad:  SAN FRANCISCO NORTH             Longitude: 122° 23.2' W (-122.38700)


                             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.