U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


To reach the tidal bench marks from Yaquina Coast Guard Station in Newport,
proceed SE on SW Bay Street for 0.08 km (0.05 mi) to Cape Perpetua Seafoods
Company at the intersection of SW Bay Street and SW Bay Boulevard.  The bench
marks are near the Coast Guard Station.  The tide gage and staff were located on
the Cape Perpetua Seafoods Company pier adjacent to the southernmost of the
processing buildings.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


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


                 PRIMARY BENCH MARK STAMPING:  T 117 1941
                         DESIGNATION:          T 117

MONUMENTATION:           Survey disk                           VM#:         8838
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:  QE1204
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   44° 37.6' N (  44.62670)          LONGITUDE: 124°  3.3' W (-124.05500)


The bench mark is a disk set flush in the sidewalk on the northernmost corner of
the intersection of SW Bay Boulevard and SW Case Street, 10 m (32 ft) NE of the
centerline of SW Case Street, 8 m (26 ft) NW of the centerline of SW Bay
Boulevard, and 2 m (5 ft) SW of a fire hydrant on the NW side of SW Bay
Boulevard.

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

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


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


                         BENCH MARK STAMPING:  Y 1 1936
                         DESIGNATION:          Y 1

MONUMENTATION:           Survey disk                           VM#:         8837
AGENCY:                  Oregon Department of Transportation
                         (ORDT)                                IDB PID#:  QE1210
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   44° 37.5' N (  44.62500)          LONGITUDE: 124°  3.5' W (-124.05800)


The bench mark is a disk set flush in a concrete monument located on the NE
sidewalk on the landing at the north end of the Yaquina Bay Bridge (U.S. Highway
101) on the NW-SE centerline of the sidewalk adjacent to the roadbed, 20 m (65
ft) NW of the northernmost pair of bridge pylons, and 5 m (16 ft) from the
centerline of U.S. Highway 101.

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

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


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


                         BENCH MARK STAMPING:  YB 32 1967
                         DESIGNATION:          YB 32

MONUMENTATION:           Bench Mark disk                       VM#:         8839
AGENCY:                  Eagle GPS Surveying Corp. (EGPSSC)    IDB PID#:  QE2626
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   44° 37.5' N (  44.62500)          LONGITUDE: 124°  3.6' W (-124.06000)


The bench mark is a disk set horizontally in a concrete monument located on the
SW sidewalk on the landing at the north end of Yaquina Bay Bridge (U.S. Highway
101), 20 m (65 ft) NW of the northernmost pair of bridge pylons, and 8 m (25 ft)
SW of the centerline of U.S. Highway 101.

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

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


                            T I D A L   D A T U M S 


Tidal datums at YAQUINA USCG STA, NEWPORT based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           November 1982 - November 1982
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9435380 SOUTH BEACH, YAQUINA RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  2.500
     MEAN HIGH WATER                            MHW    =  2.316
     MEAN TIDE LEVEL                            MTL    =  1.369
     MEAN SEA LEVEL                             MSL    =  1.356
     MEAN LOW WATER                             MLW    =  0.422
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     T 117 1941                                  5.805    3.489
     Y 1 1936                                   37.217   34.901
     YB 32 1967                                 37.183   34.867


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

                                                                                
Station ID: 9435385                         PUBLICATION DATE:  07/15/2004
Name:       YAQUINA USCG STA, NEWPORT                         
            OR
NOAA Chart: 18581                           Latitude:   44° 37.6' N (  44.62670)
USGS Quad:  YAQUINA                         Longitude: 124°  3.3' W (-124.05500)


                             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.