U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8747398 PUBLICATION DATE: 02/26/2004
Name: NORTH SHORE, BAY OF ST. LOUIS
MISSISSIPPI
NOAA Chart: 11371 Latitude: 30° 22.4' N
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.3' W
To reach the tidal bench marks from Exit 20 of Interstate Highway 10, proceed SE
on Kiln-Delisle Road for 0.5 km (0.3 mi) to an old paved road and two large
white entrance pillars on the right-hand side of the road, then turn right and
continue on the broken pavement road for 1.8 km (1.1 mi) to a circle around some
trees, then go 180 degrees around the circle and continue SW for another 0.8 km
(0.5 mi) to the abandoned Oblate Fathers Monastery. The bench marks are located
in the vicinity of the monastery. The tide gage and staff were located at the
SE corner of the abandoned pier pilings, SW of the monastery.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 7398 A 1978
DESIGNATION: 874 7398 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 10438
AGENCY: National Ocean Survey (NOS) PID:
SETTING CLASSIFICATION: Stainless steel rod
The primary bench mark is a disk located near the foot of the abandoned pier,
14.84 m (48.7 ft) NE of the northeasternmost pile from the pier, and 14 m (47
ft) north of the shoreline in a stand of pine trees. The bench mark is set 12
cm (0.4 ft) below the ground, crimped to the top of a stainless steel rod driven
21.9 m (72 ft) to refusal, and encased in a 4-inch PVC pipe and concrete
kickblock.
BENCH MARK STAMPING: 7398 B 1978
DESIGNATION: 874 7398 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 10439
AGENCY: National Ocean Survey (NOS) PID:
SETTING CLASSIFICATION: Stainless steel rod
The bench mark is a disk located 85 m (278 ft) SW of the SW corner of the
monastery, 77 m (251 ft) north of the high water shoreline, 62 m (204 ft) NNW of
bench mark 7398 A 1978, and 23.26 m (76.3 ft) west of an 0.46 m (1.5 ft)
diameter oak tree. The bench mark is set 0.18 m (0.6 ft) below the ground,
crimped to the top of a stainless steel rod driven 21.9 m (72 ft) to refusal,
and encased in a 4-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8747398 PUBLICATION DATE: 02/26/2004
Name: NORTH SHORE, BAY OF ST. LOUIS
MISSISSIPPI
NOAA Chart: 11371 Latitude: 30° 22.4' N
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.3' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7398 C 1978
DESIGNATION: 874 7398 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 10440
AGENCY: National Ocean Survey (NOS) PID:
SETTING CLASSIFICATION: Sidewalk
The bench mark is a disk set flush in a sidewalk near the NW corner of the
monastery, 73 m (239 ft) NE of bench mark 7398 B 1978, 34 m (112 ft) WNW of the
SW corner of the monastery, 31 m (101 ft) west of the NW corner, and 0.61 m (2.0
ft) SE of the west edge of the sidewalk.
BENCH MARK STAMPING: 7398 D 1978
DESIGNATION: 874 7398 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 10441
AGENCY: National Ocean Survey (NOS) PID:
SETTING CLASSIFICATION: Sidewalk
The bench mark is a disk set flush in a sidewalk north of the monastery, 77 m
(251 ft) north of the NW corner of the monastery, 12.31 m (40.4 ft) NW of the
intersection of the western north/south drive and the east/west drive north of
the monastery, and 2 m (7.0 ft) west of the curb.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8747398 PUBLICATION DATE: 02/26/2004
Name: NORTH SHORE, BAY OF ST. LOUIS
MISSISSIPPI
NOAA Chart: 11371 Latitude: 30° 22.4' N
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.3' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7398 E 1978
DESIGNATION: 874 7398 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 10442
AGENCY: National Ocean Survey (NOS) PID:
SETTING CLASSIFICATION: Stainless steel rod
The bench mark is a disk located 79 m (260 ft) NNE of the intersection of the
western north-south drive and the east-west drive, 69 m (228 ft) NE of bench
mark 7398 D 1978, 42 m (139 ft) west of the centerline of the eastern
north/south drive, 5.24 m (17.2 ft) east of the centerline of the western
north/south drive, and 1 m (4 ft) east of the east road curb. The bench mark is
set 0.18 m (0.6 ft) below ground level, crimped to the top of a stainless steel
rod driven 21.9 m (72 ft) to refusal, and encased in a 4-inch PVC pipe and
concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8747398 PUBLICATION DATE: 02/26/2004
Name: NORTH SHORE, BAY OF ST. LOUIS
MISSISSIPPI
NOAA Chart: 11371 Latitude: 30° 22.4' N
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.3' W
T I D A L D A T U M S
Tidal datums at NORTH SHORE, BAY OF ST. LOUIS based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: November 1978 - January 1979
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8747437 BAY WAVELAND YC, BAY ST. LOUIS
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER (MHHW) = 0.542
MEAN HIGH WATER (MHW) = 0.494
MEAN SEA LEVEL (MSL) = 0.274
MEAN TIDE LEVEL (MTL) = 0.271
MEAN LOW WATER (MLW) = 0.048
MEAN LOWER LOW WATER (MLLW) = 0.000
National Geodetic Vertical Datum (NGVD 29)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
7398 A 1978 1.729 1.235
7398 B 1978 1.714 1.220
7398 C 1978 3.332 2.838
7398 D 1978 3.227 2.733
7398 E 1978 3.469 2.975
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8747398 PUBLICATION DATE: 02/26/2004
Name: NORTH SHORE, BAY OF ST. LOUIS
MISSISSIPPI
NOAA Chart: 11371 Latitude: 30° 22.4' N
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.3' W
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 (NAVD 88).
NGVD 29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD 29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD 29 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 NGVD 29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD 88 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. NAVD 88 replaces NGVD 29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD 88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD 29 and NAVD 88 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 NAVD 88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD 88 elevations.
The NAVD 88 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, NAVD 88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD 88 elevations listed for
each bench mark in the NGS database.