U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8731269 PUBLICATION DATE: 03/03/2022
Name: GULF STATE PARK PIER
AL
NOAA Chart: 11376 Latitude: 30° 14.9' N ( 30.24830)
USGS Quad: GULF SHORES Longitude: 87° 40.1' W ( -87.66830)
To reach the station from the intersection of Gulf Shores Parkway 59 and Beach
Boulevard 182 in Gulf Shores, Alabama, proceed East on Beach Boulevard from
2.1km (1.3 miles). Proceed South to the entrance of the Gulf State Park Pier.
The station is located in the middle of the pier on the East side, just south of
the restroom.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 1269 C 2020
DESIGNATION: 873 1269 C
MONUMENTATION: Flange-encased Rod VM#: 23781
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBHR46
LATITUDE: 30° 15.0' N ( 30.25064) LONGITUDE: 87° 40.0' W ( -87.66700)
The primary bench mark is a stainless steel rod located at the edge of the Gulf
State Park Pier parking lot, 44.80m (147.0 ft) SE of Alabama research
groundwater level monitor station, 16.28m (53.4 ft) SE of utility pole with 2
lights on at the NE corner of the parking lot, 14.33m (47.0 ft) South of a
utility pole on the NE corner of the parking lot, and 3.35m (11.0 ft) West of
centerline of concrete bicycle path. The datum point is the top of a
flange-encased stainless steel rod driven 12.8m (42.0 ft) to refusal and
recesses 0.05m (2 inches) below the surface and encased in a concrete kick
block.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8731269 PUBLICATION DATE: 03/03/2022
Name: GULF STATE PARK PIER
AL
NOAA Chart: 11376 Latitude: 30° 14.9' N ( 30.24830)
USGS Quad: GULF SHORES Longitude: 87° 40.1' W ( -87.66830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1269 G 2020
DESIGNATION: 873 1269 G
MONUMENTATION: Bench Mark disk VM#: 23782
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Pier OPUS PID:
LATITUDE: 30° 14.8' N ( 30.24719) LONGITUDE: 87° 40.0' W ( -87.66708)
The bench mark is a disk set on the Gulf State Park Pier, located 176.1m (577.8
ft) South of second gate to the pier, 6.25m (20.5 ft) NW of fiberglass light
pole that is beyond second set of restrooms, 2.01m (6.6 ft) East of the
cenerline of pier near the second restrooms, and 0.61m (2.0 ft) East of the
utility room on the South side of the second restrooms.
BENCH MARK STAMPING: 1269 F 2020
DESIGNATION: 873 1269 F
MONUMENTATION: Bench Mark disk VM#: 23783
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete pathleading to pier OPUS PID:
LATITUDE: 30° 15.0' N ( 30.24981) LONGITUDE: 87° 40.1' W ( -87.66778)
The bench mark is a disk on the concrete path leading to the pier, 86.3m (283.1
ft) NW of the corner of the park building near the women's restroom, 50.38m
(165.3 ft) South of electrical box station #1016110 on West side of Pier Road,
13.75m (45.1 ft) SW of fire hydrant located East of the pier base, 9.14m (30.0
ft) South of pier history sign at base of pier, and 8.84m (29.0 ft) SE of a
turtle sculpture on West side at the beginning of the pier.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8731269 PUBLICATION DATE: 03/03/2022
Name: GULF STATE PARK PIER
AL
NOAA Chart: 11376 Latitude: 30° 14.9' N ( 30.24830)
USGS Quad: GULF SHORES Longitude: 87° 40.1' W ( -87.66830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1269 D 2020
DESIGNATION: 873 1269 D
MONUMENTATION: Flange-encased Rod VM#: 23784
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID:
LATITUDE: 30° 15.0' N ( 30.25075) LONGITUDE: 87° 40.1' W ( -87.66778)
The bench mark is a stainless steel rod located on the left side of the entrance
adjacent to the Gulf State Park Pier parking lot, 63.49m (208.3 ft) SE of second
white street light pole, 16.73m (54.9 ft) East of the centerline of Pier Road,
5.57m (18.3 ft) NW of first street light pole from the entrance to the parking
lot, and 0.70m (2.3 ft) North of sign reading "No Overnight Camping". The datum
point is the top of a stainless steel rod driven 12.8m (42.0 ft) to refusal and
recessed 0.05m (2 inches) below grade and encased in a concrete kickblock.
BENCH MARK STAMPING: 1269 E 2020
DESIGNATION: 873 1269 E
MONUMENTATION: Flange-encased Rod VM#: 23785
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBHQ74
LATITUDE: 30° 15.1' N ( 30.25142) LONGITUDE: 87° 40.1' W ( -87.66808)
The bench mark is a stainless steel rod located along the road leading to the
Gulf State Park Pier, 59.44m (195.0 ft) NE of cap to green electrical box
#116110, 48.77m (160.0 ft) South of Gulf State Park Pier sign at entrance on
Pier Road, 21.70m (71.3 ft) NE of utility pole #386, and 5.45m (17.9 ft) East of
centerline of Pier Road. The datum point is the top of a stainless steel rod
driven 10.36m (34.0 ft) to refusal, recessed 0.05m (2 inches) below the surface
and encased in a concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8731269 PUBLICATION DATE: 03/03/2022
Name: GULF STATE PARK PIER
AL
NOAA Chart: 11376 Latitude: 30° 14.9' N ( 30.24830)
USGS Quad: GULF SHORES Longitude: 87° 40.1' W ( -87.66830)
T I D A L D A T U M S
Tidal datums at GULF STATE PARK PIER based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: May 2021 - July 2021
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8735180 DAUPHIN ISLAND, MOBILE BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.426
MEAN HIGH WATER MHW = 0.418
MEAN TIDE LEVEL MTL = 0.211
North American Vertical Datum NAVD88 = 0.211
MEAN SEA LEVEL MSL = 0.202
MEAN LOW WATER MLW = 0.004
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
1269 C 2020 3.281 2.863
1269 G 2020 6.381 5.963
1269 F 2020 3.268 2.850
1269 D 2020 3.014 2.596
1269 E 2020 1.597 1.179
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8731269 PUBLICATION DATE: 03/03/2022
Name: GULF STATE PARK PIER
AL
NOAA Chart: 11376 Latitude: 30° 14.9' N ( 30.24830)
USGS Quad: GULF SHORES Longitude: 87° 40.1' W ( -87.66830)
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.