U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
To reach the tidal bench marks from the intersection of state highway 188 and
state highway 193 in Alabama Port, proceed west on state highway 188 for 1.6 km
(2.8 mi) to the west end of the bridge over the West Fowl River, then turn left
to a small parking area at the base of the bridge. The bench marks are located
along route 188 and the old 188 bridge. The hydro is located on the old 188
bridge and the microwave is located on the new 188 bridge over the west branch
of the river.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: E 482 1984
DESIGNATION: E 482
MONUMENTATION: Metal Rod VM#: 20112
AGENCY: NGS IDB PID#: BH1734
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BH1734
LATITUDE: 30° 22.6' N ( 30.37722) LONGITUDE: 88° 9.6' W ( -88.15972)
The primary bench mark is a rod set 16.46 m (54.0 ft) SW of the centerline of
state highway 188, 5.97 m (19.6 ft) SE of the center of Lossing Road leading SW,
0.30 m (1.0 ft) NW of a wire fence (cyclone fence), 2.07 m (6.8 ft) SE of a
powerline pole and telephone junction box, 7.28 m (23.9 ft) NW of bench mark
304-8 algs, and 4.75 m (15.6 ft) SW of a guy wire anchor, 1.70 m (5.6 ft) SE
from a witness post. The mark is 0.30 m above highway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8043 A 2011
DESIGNATION: 873 8043 A
MONUMENTATION: Tidal Station disk VM#: 20110
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete curb OPUS PID#: BBFW06
LATITUDE: 30° 22.6' N ( 30.37644) LONGITUDE: 88° 9.5' W ( -88.15892)
The bench mark is a disk set flush in the concrete curb of the bridge on the NE
side of old highway 188 bridge, next to the NOAA station, 26.03 m (85.4 ft) NNW
of the SE end of the old bridge, 15.72 m (51.6 ft) SSE of the NE end of the
bridge, 6.47 m (21.2 ft) NNE of the west side of the bridge.
BENCH MARK STAMPING: 8043 B 2011
DESIGNATION: 873 8043 B
MONUMENTATION: Tidal Station disk VM#: 20111
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete curb OPUS PID:
LATITUDE: 30° 22.6' N ( 30.37661) LONGITUDE: 88° 9.5' W ( -88.15869)
The bench mark is a disk set flush in the concrete curb of the highway 188
bridge, on the west side of the bridge near the crest of the bridge, 31.19 m
(102.3 ft) SSE of the west end of the highway 188 bridge, 4.42 m (14.5 ft) SW of
the centerline of highway 188 bridge, 0.62 m (2.0 ft) ENE of the south side of
the bridge.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: E 511 2010
DESIGNATION: E 511
MONUMENTATION: Survey disk VM#: 20113
AGENCY: Alabama DOT IDB PID#: DN3569
SETTING CLASSIFICATION: Bridge abutment OPUS PID:
LATITUDE: 30° 22.5' N ( 30.37572) LONGITUDE: 88° 9.4' W ( -88.15747)
The bench mark is a disk located on the SE end of the highway 188 bridge over
the West Fowl River, 80.85 m (265.3 ft) NW of the SE end of the guard rail on
the SE corner of the 188 bridge, 5.30 m (17.4 ft) SSW of the centerline of
highway 188, 0.25 m (0.8 ft) SE of the SE corner of the concrete handrail, set
flush in the concrete curb of the bridge.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: F 482 1984
DESIGNATION: F 482
MONUMENTATION: Metal Rod VM#: 20114
AGENCY: NGS IDB PID#: BH1735
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BH1735
LATITUDE: 30° 22.3' N ( 30.37111) LONGITUDE: 88° 8.7' W ( -88.14583)
The bench mark is a rod 14.75 m (48.4 ft) NE of the centerline of the highway
188, 6.10 m (20.0 ft) SE of the approximate center of the road, 0.98 m (3.2 ft)
SE of a powerline pole, 2.83 m (9.3 ft) NNW of a telephone junction box, and
5.35 m east of Brisbane Drive, and 4.57 m (15.0 ft) north of the SE end of an
18-inch pipe culvert under the road, 0.30 m (1.0 ft) NW from a witness post.
The mark is above level with highway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: ROW 8 70 1968
DESIGNATION: ROW 8 70
MONUMENTATION: Survey disk VM#: 20115
AGENCY: Alabama DOT IDB PID:
SETTING CLASSIFICATION: Concrete post OPUS PID:
LATITUDE: 30° 22.4' N ( 30.37389) LONGITUDE: 88° 9.3' W ( -88.15497)
The bench mark is a disk set near the intersection of state highway 188 and
Mcgraw Drive in the NE corner of the intersection in the St. Marys by the Sea
Episcopal Church property, 19.45 m (63.8 ft) south of the centerline of highway
188, 11.15 m (36.6 ft) east of the church sign, 9.00 m (29.5 ft) WNW of the
centerline of Mcgraw Drive, 2.10 m (6.9 ft) SSW of power pole number k8-94, the
monument projects 0.20 m (0.7 ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
T I D A L D A T U M S
Tidal datums at STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER based on:
LENGTH OF SERIES: 5 YEARS
TIME PERIOD: 6/12-5/14, 5/15-4/16, 8/16-7/18
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 (10/08/2017) = 2.174
MEAN HIGHER HIGH WATER MHHW = 0.513
MEAN HIGH WATER MHW = 0.466
MEAN SEA LEVEL MSL = 0.258
MEAN TIDE LEVEL MTL = 0.255
North American Vertical Datum NAVD88 = 0.237
MEAN LOW WATER MLW = 0.045
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/01/2018) = -0.528
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
E 482 1984 4.064 3.598
8043 A 2011 4.673 4.207
8043 B 2011 6.770 6.304
E 511 2010 9.373 8.907
F 482 1984 1.769 1.303
ROW 8 70 1968 2.374 1.908
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8738043 PUBLICATION DATE: 09/28/2020
Name: STATE HIGHWAY 188 BRIDGE, W. FOWL RIVER
AL
NOAA Chart: 11376 Latitude: 30° 22.6' N ( 30.37664)
USGS Quad: FOWL RIVER, AL Longitude: 88° 9.5' W ( -88.15856)
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.