U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


To reach the tidal bench marks from Astoria, take Highway 101/26 south toward
Seaside across Youngs Bay, after crossing the bay, take a right at the first
intersection onto East Harbor Drive, follow East Harbor Drive to Warrenton,
continue to follow East Harbor Drive toward Hammond and follow signs to Fort
Stevens, Hammond, in Hammond, turn right onto Iredale Street. The tidal bench
marks are located in the vicinity of the Hammond Boat Basin. Port of Portland
tide gauge is located on the Columbia River Bar Pilots station at the NW edge of
the boat basin near the entrance to the jetty.


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


                 PRIMARY BENCH MARK STAMPING:  9011 A 1982
                         DESIGNATION:          943 9011 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8869
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AC5405
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AC5405
LATITUDE:   46° 12.1' N (  46.20106)          LONGITUDE: 123° 57.0' W (-123.94928)


The primary bench mark is disk located in a grassy area just NE of Iredale
Street, 15.10 m (49.5 ft) NE of the centerline of the pavement of Iredale
Street, 15.90 m (52.1 ft) SW of the Warrenton Waterfront Trail sign along dirt
road, and 0.50 m (1.6 ft) SE of a witness post. The bench mark is set 10 cm (0.3
ft) below grade, crimped to the top of a  stainless steel rod driven 10.9 m (36
ft) to refusal, and encased in a 6-inch PVC pipe with concrete kickblock and
access cover.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  SHRILL NO 1 1971
                         DESIGNATION:          943 9011 SHRILL TIDAL 1

MONUMENTATION:           Survey disk                           VM#:         8867
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  AC5406
SETTING CLASSIFICATION:  Concrete slab                         OPUS PID:        
LATITUDE:   46° 12.3' N (  46.20500)          LONGITUDE: 123° 57.2' W (-123.95300)


The bench mark is a disk set flush in a 6-inch square concrete slab, 100 m (328
ft) north of a pole with a Standard Fuel sign, 24.38 m (80.0 ft) SE from the
centerline of a road where the road meets a parking area, 4.27 m (14.0 ft) south
from a large pine tree, 3.81 m (12.5 ft) east from the centerline of a road.



                         BENCH MARK STAMPING:  HAM BAY 1971
                         DESIGNATION:          943 9011 HAM BAY

MONUMENTATION:           Survey disk                           VM#:         8868
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Concrete slab                         OPUS PID:        
LATITUDE:   46° 12.1' N (  46.20153)          LONGITUDE: 123° 57.0' W (-123.95058)


The bench mark is a disk set in a 6-inch diameter irregularly shaped concrete
mass flush with ground level, 111.00 m (364.2 ft) NW of bench mark 9011 A 1982,
16.67 m (54.7 ft) NE of the centerline of Iredale Street, 15.30 m (50.2 ft) SE
of the apparent mean high water line, and 0.88 m (2.9 ft) north of a USE witness
post.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 B 1982
                         DESIGNATION:          943 9011 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8870
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AC5403
SETTING CLASSIFICATION:  Concrete retaining wall               OPUS PID:        
LATITUDE:   46° 12.0' N (  46.20000)          LONGITUDE: 123° 56.9' W (-123.94800)


The primary bench mark is a disk set in a 0.46 m (1.5 ft) wide retaining wall
located at the seaward end of a sidewalk that leads from the NMFS parking lot
through a hedge to the pier, 23.77 m (78.0 ft) NE of the NE edge of a parking
lot, 0.61 m (2.0 ft) NW of the north edge of a wooden walkway, 0.40 m (1.3 ft)
SW of an orange witness post, and 0.61 m (2.0 ft) below ground level.



                         BENCH MARK STAMPING:  9011 C 1982
                         DESIGNATION:          943 9011 C

MONUMENTATION:           Tidal Station disk                    VM#:         8871
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   46° 12.2' N (  46.20394)          LONGITUDE: 123° 57.2' W (-123.95361)


The bench mark is a disk located on the NW corner of a grassy area just NW of
the parking lot for Hammond Marina, 16.15 m (53.0 ft) SE from the north edge of
Lake Drive, 4.00 m (13.1 ft) NE of the northern edge of the parking area road,
and 2.53 m (8.3 ft) NE of a yield sign. The bench mark is set 9 cm (0.3 ft)
below grade, crimped to the top of a stainless steel rod driven 10.9 m (36 ft)
to refusal, and encased in a 4-inch PVC pipe with concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 D 1982
                         DESIGNATION:          943 9011 D

MONUMENTATION:           Tidal Station disk                    VM#:         8872
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   46° 12.0' N (  46.20000)          LONGITUDE: 123° 56.4' W (-123.94000)


The bench mark is a disk located near the east corner of the bait and tackle
building at the Hammond Marina, 80.77 m (265 ft) SE of the corner of Lake Drive
and Boat Basin Road, 5.79 m (19.0 ft) east of the east corner of the men's room,
and 0.55 m (1.8 ft) south of a witness post.  The bench mark is set 9 cm (0.3
ft) below grade, crimped to the top of a 9/16-inch stainless steel rod driven
12.2 m (40 ft) to refusal, and encased in a 4-inch PVC pipe with concrete
kickblock.



                         BENCH MARK STAMPING:  9011 E 1988
                         DESIGNATION:          943 9011 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         8873
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AC5404
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   46° 12.0' N (  46.20000)          LONGITUDE: 123° 56.9' W (-123.94800)


The bench mark is a disk set in the concrete steps leading to the northern
entrance of the main National Marine Fisheries Service Building in Hammond, on
the west side of the fourth step, 0.24 m (0.8 ft) east from the west edge, 0.09
m (0.3 ft) north of the north edge of the porch, and 0.85 m (2.8 ft) above
ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 G 1989
                         DESIGNATION:          943 9011 G

MONUMENTATION:           Tidal Station disk                    VM#:         8875
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete loading dock                 OPUS PID:        
LATITUDE:   46° 12.0' N (  46.20000)          LONGITUDE: 123° 56.4' W (-123.94000)


The bench mark is a disk set flush in the concrete loading dock adjacent to the
freezer building at Point Adams Packing Company, on the east side of the freezer
building and on the west side of the extension of Fleet Street, 0.88 m (2.9 ft)
north of the south edge of the loading dock, 0.88 m (2.9 ft) west of utility
pole #089907, 0.24 m (0.8 ft) west of the east edge of the loading dock, and
1.10 m (3.6 ft) above road level.



                         BENCH MARK STAMPING:  9011 H 1993
                         DESIGNATION:          943 9011 H

MONUMENTATION:           Tidal Station disk                    VM#:        16952
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete footing                      OPUS PID:        
LATITUDE:   46° 12.0' N (  46.20000)          LONGITUDE: 123° 56.4' W (-123.94000)


The bench mark is a disk set flush in a concrete footing at the SE end of the
Point Adams Packing Company's main building in Hammond, 25.15 m (82.5 ft) SW of
the NE corner of the packing company, 11.80 m (38.7 ft) NE of the SE corner of
the same building, 6.07 m (19.9 ft) SW of the SW end of the western-most of two
low concrete walls surrounding the loading dock trailer parking, 0.43 m (1.4 ft)
SE of the SE end of the building, 0.12 m (0.4 ft) NE of the SW end of the
footing, and 0.27 m (0.9 ft) above grade.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 J 1993
                         DESIGNATION:          943 9011 J TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        16953
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AC5402
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   46° 11.9' N (  46.19830)          LONGITUDE: 123° 56.8' W (-123.94700)


The bench mark is a disk located at the NE corner of the intersection of Highway
104 and the road leading to the NMFS office, across the street from the
Plhiladelphia Church in Hammond, 13.41 m (44 ft) NE of the centerline of Highway
104, 11 m (36 ft) east of the centerline of the road leading to the NMFS office,
2.26 m (7.4 ft) SE of a wooden telephone pole with a gray junction box, and 1.13
m (3.7 ft) north of an orange witness post.  The bench mark is crimped to the
top of a 9/16-inch stainless steel rod driven 19.5 m (64 ft) to refusal, and
encased in a 6-inch PVC pipe with an aluminum access cover stamped "9011 J".

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 K 1993
                         DESIGNATION:          943 9011 K TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        16954
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AC5401
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   46° 11.8' N (  46.19670)          LONGITUDE: 123° 56.6' W (-123.94300)


The bench mark is a disk located at the NE corner of the intersection of Highway
104 and Gray Street in Hammond, 10 m (33 ft) NE of the centerline of Highway
104, 4.57 m (15.0 ft) NW of the centerline of Gray Street, 3.20 m (10.5 ft)
north of a sewer manhole cover, 3.20 m (10.5 ft) east of a yellow fire hydrant,
0.52 m (1.7 ft) NW of a stop sign, and 0.3 m (1 ft) NE of an orange witness
post. The bench mark is crimped to the top of a 9/16-inch stainless steel rod
driven 15.8 m (52 ft) to refusal, and encased in a 6-inch PVC pipe with an
aluminum access cover stamped "9011 K".

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  9011 L 2011
                         DESIGNATION:          943 9011 L

MONUMENTATION:           Metal Rod                             VM#:        20162
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   46° 12.3' N (  46.20475)          LONGITUDE: 123° 57.1' W (-123.95106)


The bench mark is a stainless steel rod located on the edge of the corner of the
driveway leading to 1090 First Avenue, 9.24 m (30.3 ft) SE of the centerline of
the loop in Lake Drive, 22.00 m (72.2 ft) NW of the dispatch CONEX container for
the Columbia River Bar Pilots, 43.50 m (142.7 ft) NNE of a utility pole #055300,
4.70 m (15.4 ft) SW of the centerline of the driveway of 1090 First Avenue, 0.50
m (1.6 ft) north of an orange witness post.  The datum point is set 10 cm (0.3
ft) below grade, being the top of a stainless steel rod driven 24.3 m (80 ft)
encased in 6 inch PVC pipe with access cover.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


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


                         BENCH MARK STAMPING:  UNSTAMPED
                         DESIGNATION:          UNSTAMPED

MONUMENTATION:           Survey disk                           VM#:        20163
AGENCY:                  City of Hammond                       IDB PID#:        
SETTING CLASSIFICATION:  Set in concrete structure             OPUS PID:        
LATITUDE:   46° 12.2' N (  46.20261)          LONGITUDE: 123° 57.1' W (-123.95231)


The bench mark is a disk set flush in a large concrete loading ramp leading to
the center of the boat launch to the boat basin, 22.00 m (72.2 ft) North of a
the #10 light utility pole with power meter, 15.60 m (51.1 ft) SW of first metal
piling in the center of the boat ramp pier, 6.00 m (19.7 ft) NE of the edge of
the concrete ramp in the center of the boat launch, and is 0.60 m (1.9 ft) above
the ground surface of the boat launch.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 10 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


                            T I D A L   D A T U M S 


Tidal datums at HAMMOND, COLUMBIA RIVER based on:

     LENGTH OF SERIES:      2 YEARS
     TIME PERIOD:           May 2012 - April 2014
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9439040 ASTORIA, TONGUE POINT, COLUMBIA RIVER


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

     HIGHEST OBSERVED WATER LEVEL (11/24/2011)         =  3.559
     MEAN HIGHER HIGH WATER                     MHHW   =  2.546
     MEAN HIGH WATER                            MHW    =  2.330
     MEAN TIDE LEVEL                            MTL    =  1.357
     MEAN SEA LEVEL                             MSL    =  1.335
     MEAN LOW WATER                             MLW    =  0.383
     North American Vertical Datum              NAVD88 =  0.017
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (02/06/1989)         = -0.982

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     9011 A 1982                                 5.427    3.097
     SHRILL NO 1 1971                            3.477    1.147
     HAM BAY 1971                                5.156    2.826
     9011 B 1982                                 3.769    1.439
     9011 C 1982                                 3.781    1.451
     9011 D 1982                                 5.932    3.602
     9011 E 1988                                 5.723    3.393
     9011 G 1989                                 5.727    3.397
     9011 H 1993                                 5.074    2.744
     9011 J 1993                                 4.176    1.846
     9011 K 1993                                 3.721    1.391
     9011 L 2011                                 4.012    1.682
     UNSTAMPED                                   3.709    1.379


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 11 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


Foot Notes:

Bench marks 9011 H 1993, 9011 J 1993 and 9011 K 1993 are based on one
differential leveling connection and do not meet the quality control standards
of the NOS. Therefore, caution should be used when deriving elevations for these
marks.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 12 of 12

                                                                                
Station ID: 9439011                         PUBLICATION DATE:  07/27/2017
Name:       HAMMOND, COLUMBIA RIVER                           
            OR
NOAA Chart: 18521                           Latitude:   46° 12.1' N (  46.20170)
USGS Quad:  WARRENTON                       Longitude: 123° 56.7' W (-123.94500)


                             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.