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Bench Mark Sheet for 8735391, Dog River Bridge AL

Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


From the intersection of I-10 and State Hwy 163 (Dauphin Island Pkwy) in Mobile,
proceed south on Route 163 to the north end of the bridge over the Dog River,
then turn right on Marina Drive and the Dog River Marina. The station is in the
SE section of the dock. The microwave sensors are on the bridge.


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


                 PRIMARY BENCH MARK STAMPING:  5391 E 2011
                         DESIGNATION:          873 5391 E

MONUMENTATION:           Flange-encased Rod                    VM#:        20105
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID#: BBCL39
LATITUDE:   30° 34.2' N (  30.57033)          LONGITUDE:  88°  5.2' W ( -88.08642)


The primary bench mark is a rod located at the foot of the John Roberts Peavy
Bridge (Dog River) on the south bound side, between Highway 163 and Marina Drive
in a grassy median, 18.75 m (61.5 ft) north of the north end of the bridge
abutment, 8.30 m (27.2 ft) west of the west white line of the south bound lane
of Highway 163, 6.25 m (20.5 ft) east of the centerline of Marina Drive, and
5.10 m (16.7 ft) west of a NOAA witness post.  The bench mark is set flush with
the ground, driven 27.7 m (90.9 ft) to refusal, and encased in a 5 inch (13 cm)
PVC pipe with a concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


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


                         BENCH MARK STAMPING:  5391 A  2011
                         DESIGNATION:          873 5391 A

MONUMENTATION:           Tidal Station disk                    VM#:        20101
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bridge foundation            OPUS PID:        
LATITUDE:   30° 34.0' N (  30.56653)          LONGITUDE:  88°  5.2' W ( -88.08742)


The bench mark is a disk set flush in the SW corner of the seventh foundation
south of the north end of the bridge, located in the SE corner of the Turner
Marina property, 17.13 m (56.2 ft) NE of a light pole, 5.82 m (19.1 ft) east of
the SE corner of the foundation, and 5.81 m (19.1 ft) south of the NW corner of
the foundation.



                         BENCH MARK STAMPING:  5391 B 2011
                         DESIGNATION:          873 5391 B

MONUMENTATION:           Tidal Station disk                    VM#:        20102
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bridge foundation            OPUS PID:        
LATITUDE:   30° 34.0' N (  30.56719)          LONGITUDE:  88°  5.2' W ( -88.08719)


The bench mark is a disk set flush in the SW corner of the fifth foundation
south of the north end of the south bound side of the highway, 14.00 m (45.9 ft)
east of the centerline of a road leading to Turner Marina, 5.76 m (18.9 ft)
south of the NW corner of the foundation, 5.74 m (18.8 ft) west of the SE corner
of the foundation.

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

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


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


                         BENCH MARK STAMPING:  5391 C 2011
                         DESIGNATION:          873 5391 C

MONUMENTATION:           Tidal Station disk                    VM#:        20103
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bridge foundation            OPUS PID:        
LATITUDE:   30° 34.1' N (  30.56761)          LONGITUDE:  88°  5.2' W ( -88.08711)


The bench mark is a disk set flush under the bridge in the third foundation
south (no. 28) of the north end of the south bound side, 7.48 m (24.5 ft) east
of the centerline of Marina Drive, 5.73 m (18.8 ft) south of the NW corner of
the foundation, and 5.72 m (18.8 ft) west of the SE corner of the foundation.



                         BENCH MARK STAMPING:  5391 D 2011
                         DESIGNATION:          873 5391 D

MONUMENTATION:           Tidal Station disk                    VM#:        20104
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bridge foundation            OPUS PID:        
LATITUDE:   30° 34.1' N (  30.56828)          LONGITUDE:  88°  5.2' W ( -88.08700)


The bench mark is a disk set flush in the concrete foundation of the John Robert
Peavy bridge on the first footer of the north end of the south bound side under
the bridge, 9.07 m (29.8 ft) south of the centerline of a paved road leading to
the Mobile Yacht Club, 7.83 m (25.7 ft) east of the centerline of Marina Drive,
5.16 m (16.9 ft) west of the NE corner of the abutement, and 5.16 m (16.9 ft)
north of the SW corner of the abutement.

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

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


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


                         BENCH MARK STAMPING:  5391 F 2011
                         DESIGNATION:          873 5391 F

MONUMENTATION:           Tidal Station disk                    VM#:        20106
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bridge pavement                       OPUS PID:        
LATITUDE:   30° 33.9' N (  30.56533)          LONGITUDE:  88°  5.3' W ( -88.08794)


The bench mark is a disk set flush in the Dog River bridge near the crest of the
bridge and on the west side in the shoulder lane, 10.80 m (35.4 ft) south of a
light pole, 2.10 m (6.9 ft) west of the west whiteline on the south bound lane,
0.70 m (2.3 ft) east of the west edge of the bridge.

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

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


                            T I D A L   D A T U M S 


Tidal datums at STATE HIGHWAY 163 BRIDGE, DOG RIVER based on:

     LENGTH OF SERIES:      6 YEARS
     TIME PERIOD:           September 2011 - August 2017
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8737048 MOBILE STATE DOCKS, MOBILE RIVER


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

     HIGHEST OBSERVED WATER LEVEL (10/08/2017)         =  1.878
     MEAN HIGHER HIGH WATER                     MHHW   =  0.499
     MEAN HIGH WATER                            MHW    =  0.471
     MEAN TIDE LEVEL                            MTL    =  0.250
     MEAN SEA LEVEL                             MSL    =  0.245
     MEAN LOW WATER                             MLW    =  0.028
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/17/2018)         = -0.671

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5391 E 2011                                 1.178    0.707
     5391 A  2011                                2.254    1.783
     5391 B 2011                                 2.240    1.769
     5391 C 2011                                 2.255    1.784
     5391 D 2011                                 2.108    1.637
     5391 F 2011                                25.735   25.264


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

                                                                                
Station ID: 8735391                         PUBLICATION DATE:  04/18/2018
Name:       STATE HIGHWAY 163 BRIDGE, DOG RIVER               
            AL
NOAA Chart: 11376                           Latitude:   30° 33.9' N (  30.56517)
USGS Quad:  HOLLINGERS ISLAND               Longitude:  88°  5.3' W ( -88.08800)


                             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 8735391 Dog River Bridge, AL

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services