U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8763921 PUBLICATION DATE: 12/30/2020
Name: DOIRON LANDING
LA
NOAA Chart: 11354 Latitude: 29° 45.8' N ( 29.76403)
USGS Quad: NAPOLEONVILLE Longitude: 91° 10.6' W ( -91.17589)
From the US Post Office on 1st St, proceed on 1st St NW 0.5 km (0.3 mi) to
Brashear Ave, turn right and proceed 0.8 km (0.5 mi) NE on Brashear Ave to Sixth
St, turn left on Sixth St and proceed 0.5 km (0.3 mi) NW to Marguerite St, turn
right onto Marguerite St and proceed NE 2.2 km (1.4 mi) to the intersection with
LA 70, turn right onto LA 70 and proceed north 5.8 km (3.6 mi) to Doiron's
Landing on the left. The bench marks are surround the Landing and along LA-70.
The tide gauge is located at the river's edge on the west side of the levee.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 3921 C 2019
DESIGNATION: 876 3921 C
MONUMENTATION: Flange-encased Rod VM#: 23160
AGENCY: National Ocean Service(NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBGR60
LATITUDE: 29° 45.9' N ( 29.76483) LONGITUDE: 91° 10.5' W ( -91.17542)
The primary bench mark is a flange encased rod set in the grass between the
river and the levee at the north end of Doiron's dock, 54.35 m (178.3 ft) ENE of
the NW most wooden piling that is set on land along the river bank, 18.91 m
(62.0 ft ) west of a sheet pile wall built on top of an earthen levee and 3.51 m
(11.5 ft) south of an orange carsonite witness post. The datum point is 6.0 cm
(2 inches) below ground, being the top of a stainless steel rod driven 28.04 m
(92.0 ft) to refusal and encased in a 7.25 inch NOS logo cap with concrete kick
block.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8763921 PUBLICATION DATE: 12/30/2020
Name: DOIRON LANDING
LA
NOAA Chart: 11354 Latitude: 29° 45.8' N ( 29.76403)
USGS Quad: NAPOLEONVILLE Longitude: 91° 10.6' W ( -91.17589)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 3921 A 2019
DESIGNATION: 876 3921 A
MONUMENTATION: Tidal Station disk VM#: 23158
AGENCY: National Ocean Service(NOS) IDB PID:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76367) LONGITUDE: 91° 10.5' W ( -91.17511)
The bench mark is a disk set in a concrete gate opening that leads to Doiron's
dock, 77.7 m (254.9 ft) east of the base of a concrete walkway at the boat ramp
that leads to a floating dock, 46.8 m (153.5 ft) SE of the tallest power pole
with staff gauge attached near a small elevated building, 7.64 m (25.1 ft) south
of the northern side of the gate opening, 0.92 m (3.0 ft) SSW of the southern
end of the gate opening, 0.67 m (2.2 ft) WSW of a concrete wall with an arrow
pointing down painted on it and 0.26 m (0.9 ft) NNW of the southern end of the
concrete.
BENCH MARK STAMPING: 3921 B 2019
DESIGNATION: 876 3921 B
MONUMENTATION: Tidal Station disk VM#: 23159
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete Footer OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76406) LONGITUDE: 91° 10.5' W ( -91.17561)
The bench mark is a disk set in the concrete footer of a building at doiron's
dock, 38.37 m (125.9 ft) west of a sheet pile levee wall, 20.06 m (65.8 ft) SSW
of SE most steel bollard of two bollards located at the SW corner of a covered
vehicle port, 16.06 m (52.7 ft) NNW of the tallest power pole with staff gauge
attached, 12.45 m (40.8 ft) E of the concrete wall at a wooden dock where small
boats pull in to fuel and 1.06 m (3.5 ft) WNW of NW most 15 cm (6 inches)
diameter steel post building support.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8763921 PUBLICATION DATE: 12/30/2020
Name: DOIRON LANDING
LA
NOAA Chart: 11354 Latitude: 29° 45.8' N ( 29.76403)
USGS Quad: NAPOLEONVILLE Longitude: 91° 10.6' W ( -91.17589)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: PBM 85 EABPL 1976 USE
DESIGNATION: 85 EABPL
MONUMENTATION: Survey disk VM#: 23161
AGENCY: USE IDB PID#: AU0090
SETTING CLASSIFICATION: Galvanized steel pipe OPUS PID#: AU0090
LATITUDE: 29° 46.8' N ( 29.77967) LONGITUDE: 91° 10.6' W ( -91.17700)
The bench mark is a disk set in a galvanized pipe in the grass along the west
side of la 70, 41.67 m (136.7 ft) north of the west end of a small concrete
culvert marked by a warning road sign, 33.8 m (110.9 ft) WSW of a fire hydrant
on the east side of the road, 33.28 m (109.2 ft) ESE of a sheet pile levee,
17.40 m (57.1 ft) WNW of the centerline of LA 70, 0.15 m (0.5 ft) NNW of a metal
witness post and 0.60 m (2.0 ft) above grade.
BENCH MARK STAMPING: PBM 86 EABPL 1976 USE
DESIGNATION: 86 EABPL
MONUMENTATION: Survey disk VM#: 23162
AGENCY: USE IDB PID#: AU0092
SETTING CLASSIFICATION: Steel Pipe OPUS PID#: AU0092
LATITUDE: 29° 46.4' N ( 29.77292) LONGITUDE: 91° 10.6' W ( -91.17694)
The bench mark is a disk set in a steel pipe along the W side of LA 70, 56.72 m
(186.1 ft) south of a speed limit sign, 25.4 m (83.3 ft) west of a street sign
for Turtle Pond Road, 19.96 m (65.5 ft) east of a sheet pile levee wall, 13.90 m
(45.6 ft) west of the centerline of a road, 0.91 m (3.0 ft) SSE of a metal eye
set in a mass of concrete in the ground, 0.25 m (0.8 ft) SE of the base of a 4
cm (2 inches) diameter pipe that serves as a witness post and 0.56 m (1.8 ft)
above grade.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8763921 PUBLICATION DATE: 12/30/2020
Name: DOIRON LANDING
LA
NOAA Chart: 11354 Latitude: 29° 45.8' N ( 29.76403)
USGS Quad: NAPOLEONVILLE Longitude: 91° 10.6' W ( -91.17589)
T I D A L D A T U M S
Tidal datums at DOIRON LANDING based on:
LENGTH OF SERIES: 6 MONTHS
TIME PERIOD: January 2020 - June 2020
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8764044 BERWICK, ATCHAFALAYA RIVER, LA
Elevations of tidal datums referred to Mean Sea Level (MSL), in METERS:
MEAN SEA LEVEL MSL = 0.000
North American Vertical Datum NAVD88 = -0.955
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MSL
3921 C 2019 1.487
3921 A 2019 2.944
3921 B 2019 1.378
PBM 85 EABPL 1976 USE 1.116
PBM 86 EABPL 1976 USE 2.563
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8763921 PUBLICATION DATE: 12/30/2020
Name: DOIRON LANDING
LA
NOAA Chart: 11354 Latitude: 29° 45.8' N ( 29.76403)
USGS Quad: NAPOLEONVILLE Longitude: 91° 10.6' W ( -91.17589)
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.