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.