U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
To reach the tidal bench marks from State Highway 23 in Myrtle Grove, proceed SE
on State Highway 23 to mile marker # 45.7, then turn right and proceed SE on
Lake Judge Perez Road for 8.0 km (5.0 mi) to just before the bridge over
Hermitage Bayou, then turn left on the road before the bridge and go to the
fourth camp (Camp KE KE) on the right on the bayou. The bench marks are in the
vicinity of Camp KE KE and NW along the shell roads. The tide gage and staff
were located near the east corner of the concrete slab under Camp KE KE.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 1602 A 1985
DESIGNATION: 876 1602 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 15135
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The primary bench mark is a disk located 17.37 m (57.0 ft) WNW of the north
corner pile supporting Camp KE KE, 13.41 m (44.0 ft) ESE of the south corner
pile supporting the green camp (said green camp is 28 m (91 ft) west of Camp KE
KE), 9.63 m (31.6 ft) south of a utility pole located across the street and NW
of Camp KE KE, and 0.30 m (1.0 ft) NW of an NOS witness post. The bench mark is
set 9 cm (0.3 ft) below ground level, crimped to the top of a stainless steel
rod driven 20.7 m (68 ft) to substantial resistance, and encased in a 5-inch PVC
pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1602 F 1987
DESIGNATION: 876 1602 F TIDAL
MONUMENTATION: Tidal Station disk VM#: 11141
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The bench mark is a disk located 100.58 m (330.0 ft) NNW of bench mark 1602 C
1985, 28.59 m (93.8 ft) NE of utility pole #104, 15.06 m (49.4 ft) NNE of a "No
Dumping" sign on the SW side of the shell access road, 7.32 m (24.0 ft) SW of an
old corner wooden fence post, 3.66 m (12.0 ft) NE of the NE edge of the main
shell access road, and 0.61 m (2.0 ft) from an NOS witness post. The bench mark
is set at ground level, crimped to the top of a stainless steel rod driven 24.4
m (80 ft) to refusal, and encased in a 5-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 1602 G 1987
DESIGNATION: 876 1602 G TIDAL
MONUMENTATION: Tidal Station disk VM#: 11142
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The bench mark is a disk located 63.34 m (207.8 ft) east of utility pole #103, 9
m (30 ft) NNW of bench mark 1602 F 1987, 8.32 m (27.3 ft) west of an old corner
wooden fence post, 2.93 m (9.6 ft) NE of the edge of the main shell access road,
and 0.61 m (2.0 ft) from an NOS witness post. The bench mark is set at ground
level, crimped to the top of a stainless steel rod driven 4.9 m (16 ft), and
encased in a 5-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1602 B 1985
DESIGNATION: 876 1602 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 15136
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The bench mark is a disk located 65.71 m (215.6 ft) WSW of bench mark 1602 A
1985, 22.74 m (74.6 ft) ESE of the east corner of the Volunteer Fire Dept.
building, 17.71 m (58.1 ft) SE of a utility pole that is 8 m (25 ft) NE of the
east corner of the Fire Dept. building, 2.56 m (8.4 ft) NNW of the north corner
of a chain link fence near the bridge, and 0.3 m (1.0 ft) NE of an NOS witness
post. The bench mark is set 9 cm (0.3 ft) below ground level, crimped to the
top of a stainless steel rod driven 23.2 m (76 ft) to substantial resistance,
and encased in a 5-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 1602 C 1985
DESIGNATION: 876 1602 C TIDAL
MONUMENTATION: Bench Mark disk VM#: 15137
AGENCY: National Ocean Service (NOS) IDB PID#: AT1392
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: AT1392
LATITUDE: 29° 33.6' N ( 29.56000) LONGITUDE: 89° 53.1' W ( -89.88500)
The bench mark is a disk located 62.48 m (205.0 ft) NNW of bench mark 1602 B
1985, 29.02 m (95.2 ft) north of the north corner of the Fire Department
building, 21.76 m (71.4 ft) east of a utility pole that is NW of the Fire
Department building and SW of the main road, and 0.55 m (1.8 ft) SW of an NOS
witness post. The bench mark is set 9 cm (0.3 ft) below ground level, crimped
to the top of a stainless steel rod driven 21.9 m (72 ft) to substantial
resistance, and encased in a 5-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1602 D 1985
DESIGNATION: 876 1602 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 15138
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The bench mark is a disk located 71.32 m (234.0 ft) SW bench mark 1602 C 1985,
36.24 m (118.9 ft) WSW of the west corner of the Fire Department building, 16.00
m (52.5 ft) ENE of the SW corner of a one-lane wood bridge at its intersection
with a wood bulkhead on the SW side of a small slip or canal between the Fire
Department and Camp Hermitage, 5.79 m (19.0 ft) SE of the centerline of the
shell road, and 0.73 m (2.4 ft) SE of an NOS witness post. The bench mark is
set 9 cm (0.3 ft) below ground level, crimped to the top of a stainless steel
rod driven 20.7 m (68 ft) to substantial resistance, and encased in a 5-inch PVC
pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1602 E 1985
DESIGNATION: 876 1602 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 15139
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 33.5' N ( 29.55830) LONGITUDE: 89° 53.0' W ( -89.88330)
The bench mark is a disk located 77.39 m (253.9 ft) SW of bench mark 1602 D
1985, 18.71 m (61.4 ft) WNW of a live oak tree that is near the west corner of
the blue camp near the boat launch, 17.47 m (57.3 ft) east of a utility pole on
the NW side of the shell road leading to the boat launch, 5.12 m (16.8 ft) SE of
the centerline of the shell road, 0.70 m (2.3 ft) west of utility pole #426
which is at the corner of the shell road and the drive leading to the boat ramp,
and 0.58 m (1.9 ft) NW of an NOS witness post. The bench mark is set 9 cm (0.3
ft) below ground level, crimped to the top of a stainless steel rod driven 21.9
m (72 ft) to substantial resistance, and encased in a 5-inch PVC pipe and
concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
T I D A L D A T U M S
Tidal datums at LAKE JUDGE PEREZ, HERMITAGE BAYO based on:
LENGTH OF SERIES: 11 MONTHS
TIME PERIOD: November 1985 - September 1986
TIDAL EPOCH: 2012-2016
CONTROL TIDE STATION: 8761724 GRAND ISLE, EAST POINT
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGH WATER MHW = 0.129
MEAN HIGHER HIGH WATER MHHW = 0.127
MEAN TIDE LEVEL MTL = 0.066
MEAN SEA LEVEL MSL = 0.066
MEAN LOW WATER MLW = 0.002
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
1602 A 1985 0.069 -0.060
1602 F 1987 0.305 0.176
1602 G 1987 0.379 0.250
1602 B 1985 0.109 -0.020
1602 C 1985 0.051 -0.078
1602 D 1985 -0.201 -0.330
1602 E 1985 0.173 0.044
Foot Notes:
Bench marks 1602 F 1987 and 1602 G 1987 are based on one differential leveling
connection and do not meet the quality control standards of the NOS. Therefore,
caution should be used when deriving elevations for these marks.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8761602 PUBLICATION DATE: 04/13/2018
Name: LAKE JUDGE PEREZ, HERMITAGE BAYO
LA
NOAA Chart: 11364 Latitude: 29° 33.5' N ( 29.55830)
USGS Quad: LAKE LAURIER Longitude: 89° 53.0' W ( -89.88330)
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.