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Bench Mark Sheet for 8761385, VICINITY OF UNO CHEF MENTEUR LA

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8761385                         PUBLICATION DATE:  02/03/2015
Name:       VICINITY OF UNO CHEF MENTEUR PASS                 
            LA
NOAA Chart: 11367                           Latitude:   30°  4.1' N (  30.06875)
USGS Quad:  CHEF MENTEUR                    Longitude:  89° 48.1' W ( -89.80208)


To reach the tidal bench marks from the Hwy 90 (Chef Menteur Hwy) bridge over
Chef Menteur Pass travel NE to the first intersection after the bridge, turn
right on Marques Rd and proceed SE 0.08 km (0.05 mi) over a wooden bridge to the
University of New Orleans facility and the station.  The bench marks are located
along Marques Road and one along Highway 90.  The tide gauge is mounted to the
fixed dock on the SW side of the boathouse.


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


                 PRIMARY BENCH MARK STAMPING:  1385 A 2014
                         DESIGNATION:          876 1385 A

MONUMENTATION:           Bench Mark disk                       VM#:        21270
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID#: BBDR56
LATITUDE:   30°  4.1' N (  30.06903)          LONGITUDE:  89° 48.2' W ( -89.80308)


The primary bench mark is a disk set flush in the top of the NE wing wall of the
bridge abutment of the N side of the HWY 90 Bridge over Chef Menteur Pass, 39.32
m (129.0 ft) SW of center line of Marque Rd at HWY 90 intersection, 8.17 m (26.8
ft) NE of center of the SE side of the N most set of bridge pilings, 6.60 m
(21.6 ft) SE of centerline of HWY 90 at the N end of bridge, 1.45 m (4.7 ft) SE
of the centerline of the SE concrete guardrail, and 0.35 m (1.1 ft) above grade.



                         BENCH MARK STAMPING:  1385 B 2014
                         DESIGNATION:          876 1385 B
                         ALIAS:                 

MONUMENTATION:           Bench Mark disk                       VM#:        21271
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall cap                  OPUS PID:        
LATITUDE:   30°  4.1' N (  30.06867)          LONGITUDE:  89° 48.1' W ( -89.80153)


The bench mark is a disk set flush in the concrete top of the seawall along the
SE side of the channel cut to make the UNO facility marina, 44.65 m (146.4 ft)
NW of power pole with light and transformer GQ2 48462 51288, 32.73 m (107.3 ft)
SW of NE end of seawall, 21.32 m (69.9 ft) NNW of centerline of Marque Rd at the
corner where road turns from SW to SE, 0.31 m (1.0 ft) NW of SW edge of concrete
and 0.25 m (0.8 ft) above grade.

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

                                                                                
Station ID: 8761385                         PUBLICATION DATE:  02/03/2015
Name:       VICINITY OF UNO CHEF MENTEUR PASS                 
            LA
NOAA Chart: 11367                           Latitude:   30°  4.1' N (  30.06875)
USGS Quad:  CHEF MENTEUR                    Longitude:  89° 48.1' W ( -89.80208)


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


                         BENCH MARK STAMPING:  1385 C 2014
                         DESIGNATION:          876 1385 C

MONUMENTATION:           Bench Mark disk                       VM#:        21272
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Concrete bridge abutment              OPUS PID:        
LATITUDE:   30°  3.9' N (  30.06531)          LONGITUDE:  89° 47.9' W ( -89.79897)


The bench mark is a disk set flush in the concrete top of the NW wing wall of
the abutment on the N end of rail bridge across Cheff Menteur Pass (S of Hwy
90), 21.54 m (70.6 ft) S of the centerline of Marque Rd where it intersects with
the rail road access road, 2.77 m (9.0 ft) NW of N rail, 1.23 m (4.0 ft) N of
the NW corner of the N end of the rail bridge, 0.99 m (3.2 ft) SSE of NE end of
wing wall and 0.73 m (2.3 ft) above grade.



                         BENCH MARK STAMPING:  PENLAND 5-7-2011
                         DESIGNATION:          876 1385 PENLAND

MONUMENTATION:           Bench Mark disk                       VM#:        21273
AGENCY:                  Unknown                               IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall cap                  OPUS PID:        
LATITUDE:   30°  4.1' N (  30.06881)          LONGITUDE:  89° 48.1' W ( -89.80214)


The bench mark is a disk set flush in the concrete top of the seawall along the
NW side of the channel cut to make the UNO facility marina, 47.58 m (156.1 ft)
ESE of centerline of Marque Rd at SE end of wood bridge, 14.65 m (48.0 ft) S of
the centerline of Marque Rd at the N end of first turn after Hwy 90, 3.70 m
(12.1 ft) SW of base of exterior stairs of UNO facility,  0.31 m (1.0 ft) SE of
NW edge of concrete seawall and flush with grade.

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

                                                                                
Station ID: 8761385                         PUBLICATION DATE:  02/03/2015
Name:       VICINITY OF UNO CHEF MENTEUR PASS                 
            LA
NOAA Chart: 11367                           Latitude:   30°  4.1' N (  30.06875)
USGS Quad:  CHEF MENTEUR                    Longitude:  89° 48.1' W ( -89.80208)


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


                         BENCH MARK STAMPING:  E3146
                         DESIGNATION:          E3146

MONUMENTATION:           Bench Mark disk                       VM#:        21274
AGENCY:                  Louisiana Geological Survey (LAGS)    IDB PID#:  BH1134
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   30°  4.2' N (  30.07058)          LONGITUDE:  89° 48.1' W ( -89.80150)


The bench mark is a disk set flush in the top of a buried concrete post, 79.81 m
(261.8 ft) SW of the center line of the Chef Harbor Marina driveway, 11.52 m
(37.7 ft) SE of centerline of Hwy 90, 4.73 m (15.5 ft) SE of edge of Hwy
pavement, 4.24 m (9ft) WNW of center of AT&T buried cable junction box and 0.3 m
(0.9 ft) NW of a carsonite witness post.

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

                                                                                
Station ID: 8761385                         PUBLICATION DATE:  02/03/2015
Name:       VICINITY OF UNO CHEF MENTEUR PASS                 
            LA
NOAA Chart: 11367                           Latitude:   30°  4.1' N (  30.06875)
USGS Quad:  CHEF MENTEUR                    Longitude:  89° 48.1' W ( -89.80208)


                            T I D A L   D A T U M S 


Tidal datums at VICINITY OF UNO CHEF MENTEUR PASS based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           October 2014 - October 2014
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8761305 SHELL BEACH, LAKE BORGNE


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.346
     MEAN HIGH WATER                            MHW    =  0.337
     MEAN SEA LEVEL                             MSL    =  0.179
     MEAN TIDE LEVEL                            MTL    =  0.177
     MEAN LOW WATER                             MLW    =  0.017
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1385 A 2014                                 2.741    2.404
     1385 B 2014                                 1.455    1.118
     1385 C 2014                                 5.289    4.952
     PENLAND 5-7-2011                            1.442    1.105
     E3146                                       1.765    1.428


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

                                                                                
Station ID: 8761385                         PUBLICATION DATE:  02/03/2015
Name:       VICINITY OF UNO CHEF MENTEUR PASS                 
            LA
NOAA Chart: 11367                           Latitude:   30°  4.1' N (  30.06875)
USGS Quad:  CHEF MENTEUR                    Longitude:  89° 48.1' W ( -89.80208)


                             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 8761385 VICINITY OF UNO CHEF MENTEUR, LA

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