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Bench Mark Sheet for 9455920, Anchorage AK

Superseded Epoch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Small blue map location marker Unpublished bench mark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 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


To reach the tidal bench marks from the Ted Stevens Anchorage International
Airport, follow International Airport Road 3.8 km (2.4 mi) east to the
northbound Minnesota exit, proceed north 5.5 km (3.4 mi) to 6th Avenue and turn
right, proceed 0.9 km (0.5 mi) east to A Street and turn left, proceed north 0.9
km (0.6 mi) and to the Port Exit in the right lane, follow this curving exit
road which becomes Ocean Dock Road 1.0 km (0.6 mi) through two security check
points, veer to the right as the road becomes Anchorage Port Road and continue
north 0.8 km (0.5 mi) to the POL-1 dock.  The tide house is located in the green
metal building at the very south end of the POL-1 dock.  The bench marks are
located from the Port of Anchorage Building south 1.3 km (0.8 mi) to the
railroad yard near the Port Exit from A Street.


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


                 PRIMARY BENCH MARK STAMPING:  NO 15 RESET 1966
                         DESIGNATION:          945 5920 TIDAL 15 1966

MONUMENTATION:           Bench Mark disk                       VM#:         1332
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TT0711
SETTING CLASSIFICATION:  Concrete dock                         OPUS PID:        
LATITUDE:   61° 14.4' N (  61.23953)          LONGITUDE: 149° 53.3' W (-149.88769)


The primary bench mark is a disk set flush with the concrete surface of the
Anchorage City Dock, 101 m ( (330 ft) NW of bench mark 5920 B 1980, 9.45 m (31.0
ft) south of the north edge of the dock, 4.85 m (15.9 ft) NW of the NE corner of
the Port of Anchorage Office building, 3.84 m (12.6 ft) NE of the north door of
the office, and 2.87 m (9.4 ft) east of a 1 m (4 ft) high concrete deck landing
for the office north door.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  B 75 1964
                         DESIGNATION:          B 75

MONUMENTATION:           Bench Mark disk                       VM#:         1334
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TT0712
SETTING CLASSIFICATION:  Concrete dock                         OPUS PID:        
LATITUDE:   61° 14.3' N (  61.23844)          LONGITUDE: 149° 53.3' W (-149.88828)


The bench mark is a disk set near the SE corner of Anchorage City Dock, 25 m (81
ft) south of the SE corner of the Port of Anchorage Office building, 12 m (40
ft) SE of the east railroad track, 4 m (12 ft) east of the NE corner of the
north end of the approach to the dock, 0.30 m (1.0 ft) north of the north side
of a concrete bull rail at the point where it makes an oblique turn to the NE,
and set flush with the concrete surface.



                         BENCH MARK STAMPING:  TIDAL 16 1966
                         DESIGNATION:          945 5920 TIDAL 16

MONUMENTATION:           Bench Mark disk                       VM#:         1335
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TT0713
SETTING CLASSIFICATION:  Concrete deck                         OPUS PID:        
LATITUDE:   61° 14.3' N (  61.23767)          LONGITUDE: 149° 53.4' W (-149.89053)


The bench mark is a disk set on the west side of the Anchorage Dock near the
south end, 10.24 m (33.6 ft) west of the SW corner of the 3 m x 4 m (10 ft x 12
ft) building which houses the tide gauges, 3.35 m (11.0 ft) north of the SW
corner of the dock, 1.52 m (5.0 ft) north of the center of a mooring bit, 0.30 m
(1.0 ft) south of the south end of the west bull rail, and flush with the
concrete surface.  NOTE:  There is a USACE survey disk within a meter of this
mark, so make sure to survey to the correct mark.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  5920 B 1980
                         DESIGNATION:          945 5920 B

MONUMENTATION:           Tidal Station disk                    VM#:         1336
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   61° 14.3' N (  61.23914)          LONGITUDE: 149° 53.2' W (-149.88586)


The bench mark is a disk set near the NW corner of the blue and white repair
shop building belonging to the Port of Anchorage, 101 m (330 ft) SE of bench
mark NO 15 RESET 1966, 27 m (90 ft) south of light pole LP 5, 0.98 m (3.2 ft)
north of the NW edge of a 5 m (15 ft) wide doorway, and 0.37 m (1.2 ft) NE of NW
corner of the repair shop.  The bench mark is 0.06 m (0.2 ft) below ground,
being the top of a disk set on a copper-clad steel rod driven to a depth of 21.6
m (71 ft).



                         BENCH MARK STAMPING:  5920 D 1980
                         DESIGNATION:          945 5920 D

MONUMENTATION:           Tidal Station disk                    VM#:         1337
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   61° 13.6' N (  61.22667)          LONGITUDE: 149° 53.3' W (-149.88892)


The bench mark is a disk set at the SE corner of the intersection of Ocean Dock
Road and West Loop Road, 46.88 m (153.8 ft) east of a fire plug, 19.08 m (62.6
ft) NE of a steel light pole, 10.76 m (35.3 ft) south of the center of a traffic
island of Loop Road, 2.32 m (7.6 ft) north of a cyclone fence, 1.40 m (4.6 ft)
east of the western end of a steel guard rail, and 0.79 m (2.6 ft) north of a
witness post.  The bench mark is set 0.06 m (0.2 ft) below ground level, set on 
copper-clad steel rod driven to a depth of 19.5 m (64 ft).

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  5920 THERMO 1 1988
                         DESIGNATION:          945 5920 THERMO 1

MONUMENTATION:           Tidal Station disk                    VM#:         1339
AGENCY:                  National Ocean Survey (NOS)           IDB PID:         
SETTING CLASSIFICATION:  Thermopile deep rod                   OPUS PID:        
LATITUDE:   61° 14.0' N (  61.23358)          LONGITUDE: 149° 53.3' W (-149.88781)


The bench mark is an aluminum disk located west of Tesoro Alaska at 1331
Tidewater Road at the intersection of Terminal Road and Anchorage Port Road,
21.85 m (71.5 ft) west of the first light pole east of the intersection on the
North side of Terminal Rd, 7.06 m (23.2 ft) NNE of the stop sign, 6.92 m (22.7
ft) east of the eastern-most rail of the railroad tracks, and 1.62 m (5.3 ft)
west of a 0.6 m (2 ft) high 6-inch square concrete post.  The bench mark is set
0.15 m (0.5 ft) above ground level, attached to a 1-inch diameter 3.20 m (10.5
ft) long thermopile cylinder driven to a depth of 3.1 m (10 ft), and encased in
a 4-inch PVC pipe with concrete kick block.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  BM 9 1918
                         DESIGNATION:          945 5920 TIDAL 9

MONUMENTATION:           Bench Mark disk                       VM#:        12645
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  TT0719
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   61° 13.6' N (  61.22592)          LONGITUDE: 149° 53.1' W (-149.88572)


The bench mark is a disk set on SE side of the concrete foundation of a 1 m (3
ft) diameter manhole cover in the yard of the Alaska Railroad, 1.5 km (0.9 mi)
south of Port of Anchorage, 41 m (136 ft) north of NE corner of Building No. 3,
40.39 m (132.5 ft) NW of fire hydrant, 27 m (89 ft) SSW of SW corner of
northwestern-most support pillar for elevated road, 15.03 m (49.3 ft) NW of the
second most northwesterly support on west side of elevated road, 14.60 m (47.9
ft) NW of an orange paint arrow on the second most northwesterly suport on the
west side of the elevated road, 0.55 m (1.8 ft) SE (directly toward the orange
paint arrow) from the center of the 3 ft diameter manhole cover lid, and 0.15 m
(0.5 ft) below the top of the manhole cover.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  5920 F 2000
                         DESIGNATION:          945 5920 F

MONUMENTATION:           Tidal Station disk                    VM#:        16233
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete platform                     OPUS PID:        
LATITUDE:   61° 14.2' N (  61.23669)          LONGITUDE: 149° 53.2' W (-149.88589)


The bench mark is a disk set in a concrete platform on the north side of steps
leading to the Horizon Lines office building at 1717 Port Road at the Port of
Anchorage, 6.72 m (22.05 ft)  east of a flagpole, 4.90 m (16.01 ft) NW from of
the double door front entrance to the office building, and 0.50 m (1.64 ft)
above sidewalk.



                         BENCH MARK STAMPING:  5920 G 2011
                         DESIGNATION:          945 5920 G

MONUMENTATION:           Tidal Station disk                    VM#:        20098
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Utility vault                         OPUS PID:        
LATITUDE:   61° 14.1' N (  61.23506)          LONGITUDE: 149° 53.2' W (-149.88714)


The bench mark is a disk set in a 1.80 m X 2.10 m concrete utility vault located
on the west side of Tidewater Road, 25.30 m (83.0 ft) east of the most eastern
rail of the railroad tracks that run north and south, 8.30 m (27.2 ft) west of
the centerline of Tidewater Road, and 7.30 m (23.9 ft) south of a yellow fire
hydrant.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


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


                         BENCH MARK STAMPING:  5920 H 2011
                         DESIGNATION:          945 5920 H

MONUMENTATION:           Tidal Station disk                    VM#:        20099
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   61° 13.8' N (  61.23025)          LONGITUDE: 149° 53.4' W (-149.89022)


The bench mark is a disk set in a concrete sidewalk on the west side of Chevron
Corporation at 459 West Bluff Road, 12.25 m (40.1 ft) north of the centerline of
West Bluff Road, 1.60 m (5.2 ft) NW of the SW corner of the Chevron Building,
1.20 m (3.9 ft) east of the most eastern rail road track, and 0.20 m (0.65 ft)
above ground level.  

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


                            T I D A L   D A T U M S 


Tidal datums at ANCHORAGE, KNIK ARM, COOK INLET based on:

     LENGTH OF SERIES:      5 YEARS
     TIME PERIOD:           January 1997 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (11/06/2002)         = 10.624
     MEAN HIGHER HIGH WATER                     MHHW   =  8.889
     MEAN HIGH WATER                            MHW    =  8.667
     MEAN SEA LEVEL                             MSL    =  5.020
     MEAN TIDE LEVEL                            MTL    =  4.676
     MEAN LOW WATER                             MLW    =  0.685
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (12/25/1999)         = -1.949

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 15 RESET 1966                           11.320    2.653
     B 75 1964                                  11.221    2.554
     TIDAL 16 1966                              12.355    3.688
     5920 B 1980                                11.875    3.208
     5920 D 1980                                13.623    4.956
     5920 THERMO 1 1988                         11.374    2.707
     BM 9 1918                                  12.570    3.903
     5920 F 2000                                12.117    3.450
     5920 G 2011                                11.369    2.702
     5920 H 2011                                11.700    3.033


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


Foot Notes:

Bench marks 5920 G 2011 and 5920 H 2011 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 10 of 10

                                                                                
Station ID: 9455920                         PUBLICATION DATE:  10/24/2011
Name:       ANCHORAGE, KNIK ARM, COOK INLET                   
            AK
NOAA Chart: 16664                           Latitude:   61° 14.3' N (  61.23831)
USGS Quad:  ANCHORAGE A-8                   Longitude: 149° 53.4' W (-149.89000)


                             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.

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Products available at 9455920 Anchorage, AK

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