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Bench Mark Sheet for 9466057, Popokamute (Kokokamute), Kuskokwim River 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 9466057                         PUBLICATION DATE:  01/12/2012
Name:       POPOKAMUTE, KUSKOKWIM RIVER                       
            AK
NOAA Chart: 16300                           Latitude:   60°  7.4' N (  60.12328)
USGS Quad:  BAIRD INLET (A-2)               Longitude: 162° 30.0' W (-162.50036)


To reach the tidal bench marks from Bethel Alaska, proceed by charter float
plane 85 km (53 mi) SSW to a small peninsula formed by the western bank of the
Kuskokwim and a tidal slough that runs NNW to SSE. The bench marks are located
along the west bank of the slough and start approximately 320 m (0.2 mi) NNW of
the mouth of the slough. Two gauges were deployed on the west bank of the slough
monitoring the water level there, and a third gauge was installed to monitor the
water level of the Kuskokwim approximately 900 m (0.56 mi) to the NNE across the
slough.


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


                 PRIMARY BENCH MARK STAMPING:  6057 A 2010
                         DESIGNATION:          946 6057 A

MONUMENTATION:           Metal Rod                             VM#:        19803
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless Steel rod                   OPUS PID:        
LATITUDE:   60°  6.9' N (  60.11486)          LONGITUDE: 162° 30.1' W (-162.50214)


The primary bench mark is a metal rod set in a grassy shoal near the mouth of an
unnamed tidal slough, 66.50 m (218.2 ft) SSW of bench mark 946 6057 B, 48.93 m
(160.5 ft) north of lone 1.4 m wide stump with growing vegetation and 15.75 m
(51.7 ft) WNW of 2 m bluff edge to slough.  The datum point is set 11 cm (0.36
ft) below grade, being the top of a stainless steel rod driven 10.91 m (35.8 ft)
to refusal and encased in a 6-inch PVC pipe with a 7-inch diameter National
Ocean Service logo cap.

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

                                                                                
Station ID: 9466057                         PUBLICATION DATE:  01/12/2012
Name:       POPOKAMUTE, KUSKOKWIM RIVER                       
            AK
NOAA Chart: 16300                           Latitude:   60°  7.4' N (  60.12328)
USGS Quad:  BAIRD INLET (A-2)               Longitude: 162° 30.0' W (-162.50036)


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


                         BENCH MARK STAMPING:  6057 B 2010
                         DESIGNATION:          946 6057 B

MONUMENTATION:           Metal Rod                             VM#:        19804
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless Steel rod                   OPUS PID:        
LATITUDE:   60°  6.9' N (  60.11539)          LONGITUDE: 162° 30.1' W (-162.50197)


The bench mark is a metal rod set in a grassy shoal near the mouth of an unnamed
tidal slough, 69.52 m (228.1 ft) SSE of bench mark 946 6057 C, 62.20 m (204.1
ft) SSE of lone 1.4 m wide stump with growing vegetation and 17.69 m (58.0 ft)
west of 2 m bluff edge to slough.  The datum point is set 4 cm (0.13 ft) below
grade, being the top of a stainless steel rod driven 10.96 m (36.0 ft) to
refusal and encased in a 6-inch PVC pipe with a 7-inch diameter National Ocean
Service logo cap.



                         BENCH MARK STAMPING:  6057 C 2010
                         DESIGNATION:          946 6057 C

MONUMENTATION:           Metal Rod                             VM#:        19805
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless Steel rod                   OPUS PID#: BBCC54
LATITUDE:   60°  7.0' N (  60.11594)          LONGITUDE: 162° 30.2' W (-162.50256)


The bench mark is a metal rod set in a grassy shoal near the mouth of an unnamed
tidal slough, 66.43 m (217.9 ft) SSE of bench mark 946 6057 D, 38.60 m (126.6
ft) WSW of high water debris line, and 8.33 m (27.3 ft) WNW of a lone 1.4 m wide
stump with growing vegetation.  The datum point is set 10 cm (0.33 ft) below
grade, being the top of a stainless steel rod driven 12.2 m (40.0 ft) to refusal
and encased in a 6-inch PVC pipe with the top of a 7-inch diameter National
Ocean Service logo.

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

                                                                                
Station ID: 9466057                         PUBLICATION DATE:  01/12/2012
Name:       POPOKAMUTE, KUSKOKWIM RIVER                       
            AK
NOAA Chart: 16300                           Latitude:   60°  7.4' N (  60.12328)
USGS Quad:  BAIRD INLET (A-2)               Longitude: 162° 30.0' W (-162.50036)


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


                         BENCH MARK STAMPING:  6057 D 2010
                         DESIGNATION:          946 6057 D

MONUMENTATION:           Metal Rod                             VM#:        19806
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless Steel rod                   OPUS PID:        
LATITUDE:   60°  6.9' N (  60.11539)          LONGITUDE: 162° 30.1' W (-162.50197)


The bench mark is a metal rod set in a grassy shoal near the mouth of an unnamed
tidal slough, 75.40 m (247.4 ft) NNW of lone 1.4 m wide stump with growing
vegetation, 65.55 m (215.1 ft) SSE of bench mark 946 6057 E and 38.29 m (125.6
ft) WSW of high water debris line on top of 2 m bluff edge to slough.  The datum
point is set 15 cm (0.49 ft) below grade, being the top of a stainless steel rod
driven 11.00 m (36.1 ft) to refusal and encased in a 6-inch PVC pipe with the
top of a 7-inch diameter National Ocean Service logo cap.



                         BENCH MARK STAMPING:  6057 E 2010
                         DESIGNATION:          9466057 E

MONUMENTATION:           Metal Rod                             VM#:        19807
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless Steel rod                   OPUS PID:        
LATITUDE:   60°  6.0' N (  60.10036)          LONGITUDE: 162° 30.2' W (-162.50361)


The bench mark is a metal rod set in a grassy shoal near the mouth of an unnamed
tidal slough, 66.56 m (218.4 ft) NW of benchmark 946 6057 D, 41.05 m (134.7 ft)
SSE of intersection of bluff and high water, 17.82 m (58.5 ft) SW of high water
debris line on top of 2 m bluff edge to slough.  The datum point is set 11 cm
(0.36 ft) below grade, being the top of a stainless steel rod driven 11.03 m
(36.2 ft) to refusal and encased in a 6-inch PVC pipe with a 7-inch diameter
National Ocean Service logo cap.

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

                                                                                
Station ID: 9466057                         PUBLICATION DATE:  01/12/2012
Name:       POPOKAMUTE, KUSKOKWIM RIVER                       
            AK
NOAA Chart: 16300                           Latitude:   60°  7.4' N (  60.12328)
USGS Quad:  BAIRD INLET (A-2)               Longitude: 162° 30.0' W (-162.50036)


                            T I D A L   D A T U M S 


Tidal datums at POPOKAMUTE, KUSKOKWIM RIVER based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           July 2011 - August 2011
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     MEAN HIGHER HIGH WATER                     MHHW   =  3.359
     MEAN HIGH WATER                            MHW    =  2.718
     MEAN SEA LEVEL                             MSL    =  1.539
     MEAN TIDE LEVEL                            MTL    =  1.453
     MEAN LOW WATER                             MLW    =  0.187
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     6057 A 2010                                 3.855    1.137
     6057 B 2010                                 3.975    1.257
     6057 C 2010                                 3.875    1.157
     6057 D 2010                                 3.893    1.175
     6057 E 2010                                 3.987    1.269


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

                                                                                
Station ID: 9466057                         PUBLICATION DATE:  01/12/2012
Name:       POPOKAMUTE, KUSKOKWIM RIVER                       
            AK
NOAA Chart: 16300                           Latitude:   60°  7.4' N (  60.12328)
USGS Quad:  BAIRD INLET (A-2)               Longitude: 162° 30.0' W (-162.50036)


                             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 9466057 Popokamute (Kokokamute), Kuskokwim River, AK

Revised: 08/08/2018
NOAA / National Ocean Service
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