U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
To reach the tidal bench marks from the intersection of U.S. Highway 90 and
North Beach Boulevard at the west end of the U.S. Highway 90 bridge over St.
Louis Bay, proceed 0.6 km (0.4 mi) north on North Beach Boulevard to Bay
Waveland Yacht Club. The bench marks are located in the vicinity of the yacht
club and near U.S. Highway 90. The tide gage is located offshore a few hundred
yards north of the yacht club, on the yellow pile.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 7437 C 1978
DESIGNATION: 874 7437 C
MONUMENTATION: Bench Mark disk VM#: 802
AGENCY: National Ocean Survey (NOS) IDB PID:
SETTING CLASSIFICATION: Mass of concrete OPUS PID:
LATITUDE: 30° 19.4' N ( 30.32389) LONGITUDE: 89° 19.7' W ( -89.32750)
The primary bench mark is a disk set next to a utility pole in a park directly
across the street from the yacht club, 15.70 m (51.51 ft) west of an old seawall
corner on the north side of the gate to the yacht club, and 7.62 m (25.00 ft) SW
of the centerline of North Beach Boulevard. The bench mark is set 0.24 m (0.79
ft) below ground level, crimped to the top of a stainless steel rod driven to an
unspecified depth, 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 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 2 1968
DESIGNATION: 874 7437 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 799
AGENCY: National Ocean Survey (NOS) IDB PID#: BH0936
SETTING CLASSIFICATION: Concrete seawall OPUS PID:
LATITUDE: 30° 19.4' N ( 30.32389) LONGITUDE: 89° 19.7' W ( -89.32750)
The bench mark is a disk set on the top at the SE end of a seawall, 114.60 m
(375.98 ft) SE of bench mark NO 1 1968, 11.06 m (36.29 ft) west of the south
corner of a steel fence around the Yacht Club, 5.49 m (18.01 ft) NE of the
centerline of the boulevard, 0.98 m (3.22 ft) NW of the seawall, and about level
with the boulevard.
BENCH MARK STAMPING: 7437 E 1991
DESIGNATION: 874 7437 E
MONUMENTATION: Tidal Station disk VM#: 1808
AGENCY: National Ocean Survey (NOS) IDB PID#: AB7179
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: AB7179
LATITUDE: 30° 19.5' N ( 30.32444) LONGITUDE: 89° 19.6' W ( -89.32694)
The bench mark is a disk located 39 m (128.0 ft) west of the SW corner of the
boat equipment storage shed, 32.31 m (106.00 ft) NW of the power pole at the
east end of the boat slips, 19.81 m (64.99 ft) east of the Marina Electric
Meter/Power Pole with light, 5.00 m (16.40 ft) north of a concrete parking lot
drainage basin, and 0.34 m (1.12 ft) south of the east-west concrete walkway
along the BWYC marina boat slips. The bench mark is set 6 cm (0.2 ft) below the
ground, crimped to the top of a stainless steel rod driven 15.3 m ( 50.2 ft) to
refusal, and encased in a 6-inch DIA PVC surrounded by concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7437 H 1991
DESIGNATION: 874 7437 H
MONUMENTATION: Tidal Station disk VM#: 1811
AGENCY: National Ocean Survey (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBFW65
LATITUDE: 30° 19.3' N ( 30.32150) LONGITUDE: 89° 19.5' W ( -89.32522)
The bench mark is a disk located 336.0 m (1102.4 ft) south along North Beach
Drive from the centerline of the driveway entrance to the BWYC, 30.78 m (100.98
ft) north of power pole NO. 640, 16.76 m (54.99 ft) NW of a twin live oak tree,
10.79 m (35.40 ft) east of a fire hydrant, 6.98 m (22.90 ft) south of power pole
NO. 644, and 4.85 m (15.91 ft) east of the centerline of North Beach Drive. The
bench mark is set 0.06 m (0.20 ft) below ground level, crimped to a stainless
steel rod driven 20.12 m (66.01 ft) to refusal, and encased in a 6-inch PVC pipe
and concrete kickblock.
BENCH MARK STAMPING: 7437 J 2008
DESIGNATION: 874 7437 J
MONUMENTATION: Bench Mark disk VM#: 18831
AGENCY: NOS IDB PID:
SETTING CLASSIFICATION: BWYC concrete foundation OPUS PID:
LATITUDE: 30° 19.5' N ( 30.32511) LONGITUDE: 89° 19.5' W ( -89.32575)
The bench mark is a disk set flush in the NE corner of the Bay-Waveland Yacht
Club concrete foundation, 22 m (72.2 ft) west of the BWYC flagpole, 41 m (134.5
ft) SE of the bulkhead along the south side of the main basin, 37 m (121.4 ft)
NE of the BWYC entrance patio, 41 m (134.5 ft) NE of the SW corner of the BWYC
concrete foundation, 0.3 m (1.0 ft) west of the NE concrete foundation pillar of
the BWYC.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 874 7437 SPIP 2008
DESIGNATION: 874 7437 SPIP
MONUMENTATION: Bench Mark disk VM#: 18834
AGENCY: NOS IDB PID:
SETTING CLASSIFICATION: Set in the top platform of the SentinelOPUS PID:
LATITUDE: 30° 19.6' N ( 30.32636) LONGITUDE: 89° 19.5' W ( -89.32578)
The bench mark is a disk set flush on top of the SE corner of the Davit Plate
located on the NW corner of the 3 x 3 m (9.8 ft) platform, 3.1 m (10.17 ft) NW
of the SW corner of the 3 x 3 m (9.8 ft) platform, 2.2 m (7.2 ft) NE of the SW
corner of the 3 x 3 m (9.8 ft) platform, 1.5 m (4.9 ft) SE of the NW corner of
the 3 x 3 m (9.8 ft) platform.
BENCH MARK STAMPING: 7437 K 2010
DESIGNATION: 874 7437 K
MONUMENTATION: Flange-encased Rod VM#: 19737
AGENCY: National Ocean Survey/Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBGR81
LATITUDE: 30° 19.3' N ( 30.32231) LONGITUDE: 89° 19.6' W ( -89.32597)
The bench mark is a flange-encased rod located 140.25 ft (42.74 m) NW of the
telephone pole number 646, 71.5 ft (21.79 m) WSW of the fire hydrant number
090061, 70.4 ft (21.45 m) SSE of the telephone pole number 645, 37.33 ft (11.37
m) SW of the telephone pole number 1099, and 34 ft (10.36 m) of the manhole
number 166, and 2 ft (0.60 m) west of a 3 inch (7.62 cm) PVC witness post. The
datum point set 6 inches (15.24 cm) below the ground, being the top of a
stainless steel rod driven 89.9 ft (27.40 m) to refusal, and encased in a 5 inch
(12.7 cm) National Geodetic Survey logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7437 L 2010
DESIGNATION: 874 7437 L
MONUMENTATION: Flange-encased Rod VM#: 19738
AGENCY: National Ocean Survey/Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBGR80
LATITUDE: 30° 19.5' N ( 30.32436) LONGITUDE: 89° 19.7' W ( -89.32806)
The bench mark is a flange-encased rod located 73 ft (22.25 m) ESE of a
telephone pole number 5-34, 52.25 ft (15.92 m) SSW of a telephone pole number
698, 27 ft (8.22 m) SSW of the centerline of north beach boulevard, 12 ft (3.65
m) north of a telephone pole number 5-35, 8.52 ft (2.59 m) SSW of a seawall, and
2 ft (0.60 m) SW of a 3 inch PVC witness post. The datum point is set 6 inches
(15.24 cm) below the ground, being the top of a stainless steel rod driven 89.9
ft (27.40 m) to refusal, and encased in 5 inch NGS logo cap.
BENCH MARK STAMPING: 7437 M 2010
DESIGNATION: 874 7437 M
MONUMENTATION: Flange-encased Rod VM#: 19739
AGENCY: National Ocean Survey/Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBFW66
LATITUDE: 30° 19.5' N ( 30.32536) LONGITUDE: 89° 19.7' W ( -89.32900)
The bench mark is a flange-encased rod located 153.33 ft (46.7 m) north of a
fire hydrant number 454310, 126.5 ft (38.55 m) east of a telephone pole number
710, 54.5 ft (16.6 m) NE of a telephone pole number 4-40, 28.5 ft (8.68 m) NE of
the centerline of north beach boulevard, 11.5 ft (3.50 m) NE of the top step of
the seawall, and 2 ft (0.60 m) SW of a 3 inch (7.62 cm) PVC witness post. The
datum point is set 6 inches (15.24 cm) below the ground, being the top of a
stainless steel rod driven 89.7 ft (27.34 m) to refusal, and encased in a 5-inch
(12.7 cm) National Geodetic Survey logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
T I D A L D A T U M S
Tidal datums at BAY WAVELAND YACHT CLUB, BAY ST. LOUIS based on:
LENGTH OF SERIES: 9 YEARS
TIME PERIOD: 7/07-6/11,8/11-7/12,10/13-9/15,2/16-1/18
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8741533 PASCAGOULA NOAA LAB, PASCAGOULA RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (09/01/2008) = 3.317
MEAN HIGHER HIGH WATER MHHW = 0.547
MEAN HIGH WATER MHW = 0.506
MEAN SEA LEVEL MSL = 0.276
MEAN TIDE LEVEL MTL = 0.275
North American Vertical Datum NAVD88 = 0.249
MEAN LOW WATER MLW = 0.044
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (09/02/1985) = -1.200
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
7437 C 1978 1.661 1.155
NO 2 1968 2.507 2.001
7437 E 1991 1.226 0.720
7437 H 1991 3.488 2.982
7437 J 2008 1.833 1.327
874 7437 SPIP 2008 7.771 7.265
7437 K 2010 3.023 2.517
7437 L 2010 1.307 0.801
7437 M 2010 0.955 0.449
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
Foot Notes:
Notice: In July, 2021, CO-OPS corrected the data at this location dating back to
2005 to address observed shifts in the local terrestrial reference frame. A
series of data correctors were applied to ensure that all data at this location
is referenced to the same zero reference plane from when the station was
originally installed. The water level observations have been corrected by
between 1 to 2.5 cm depending on the date
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 8747437 PUBLICATION DATE: 08/04/2021
Name: BAY WAVELAND YACHT CLUB, BAY ST. LOUIS
MS
NOAA Chart: 11371 Latitude: 30° 19.5' N ( 30.32500)
USGS Quad: BAY ST. LOUIS Longitude: 89° 19.5' W ( -89.32500)
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.