U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 08/20/1990
Station ID: 8745557 SUPERCEDED DATE: 04/21/2003
Name: GULFPORT HARBOR, MISSISSIPPI SOUND
MISSISSIPPI
NOAA Chart: 11372 Latitude: 30° 1.6' N
USGS Quad: GULFPORTSOUTH Longitude: 89° 4.9' W
To reach the tidal bench marks from the intersection of 20th Avenue and U.S.
Highway 90 in Gulfport, proceed south on 20th Avenue for 0.4 mile (0.6 km) to
the foot of a jetty leading to the SE. Proceed by foot along the jetty for 1000
feet (305 m) to the John C. Moses Fishing Pier. The bench marks are north of
the Moses Pier along 20th Avenue. The tide gage and staff were on the east side
of the pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5557 A 1979
MONUMENTATION: Survey Disk VM#: 10380
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is near the foot of the jetty leading to the fishing pier, 410
feet (125 m) east of the SE corner of Gulfport Harbor Marina, 364 feet (111 m)
east of the sea wall cap, 100 feet (30 m) NW of the shoreline intersection with
the jetty on the south side of the walkway, and 11 feet (3 m) south of the
centerline of the asphalt walkway to Moses Pier. The bench mark is 0.4 foot
(0.1 m) below ground level, crimped to a stainless steel rod driven 50 feet (15
m) to refusal, and encased in a 4-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: NO 1 1969
MONUMENTATION: Survey Disk VM#: 10377
AGENCY: PID#: BH0867
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the base of a sea wall along the east side of
Gulfport Harbor Marina, 16.5 feet (5.0 m) west of the centerline of 20th Avenue,
and 8.0 feet (2.4 m) south of the southside entrance to Pier #2.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 08/20/1990
Station ID: 8745557 SUPERCEDED DATE: 04/21/2003
Name: GULFPORT HARBOR, MISSISSIPPI SOUND
MISSISSIPPI
NOAA Chart: 11372 Latitude: 30° 1.6' N
USGS Quad: GULFPORTSOUTH Longitude: 89° 4.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 2 1969
MONUMENTATION: Survey Disk VM#: 10378
AGENCY: PID#: BH0865
SETTING CLASSIFICATION: Retaining Wall
The bench mark is set flush in the concrete retaining wall on the east side of
Gulfport Harbor Marina, 116.3 feet (35.4 m) NE of the entrance in the sea wall
to Pier #2, and 20.3 feet (6.2 m) east of the centerline of 20th Avenue.
BENCH MARK STAMPING: NO 3 1969
MONUMENTATION: Survey Disk VM#: 10379
AGENCY: PID#: BH0864
SETTING CLASSIFICATION: Retaining Wall
The bench mark is on the same retaining wall and 244.4 feet (74.5 m) north of
Bench Mark NO 2 1969, and 74.7 feet (22.8 m) SE of the north end of the Gulfport
Harbor Marina sea wall.
BENCH MARK STAMPING: 5557 B 1979
MONUMENTATION: Survey Disk VM#: 10381
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is near the intersection of 20th Avenue and the walkway leading
to Moses Pier, 353 feet (108 m) west of Bench Mark 5557 A 1979, 60 feet (18 m)
east of the SE corner of Gulfport Harbor Marina, 46 feet (14 m) east of the
centerline of the east Gulfport Harbor road, 18 feet (5 m) east of the sea wall
cap, and 1.8 feet (0.5 m) north of utility pole #MPCO-774-CP-UO-LR-FT-540 with
meter. The bench mark is 0.4 foot (0.1 m) below ground level, crimped to a
stainless steel rod driven 50 feet (15 m) to substantial resistance, 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 3 of 5
PUBLICATION DATE: 08/20/1990
Station ID: 8745557 SUPERCEDED DATE: 04/21/2003
Name: GULFPORT HARBOR, MISSISSIPPI SOUND
MISSISSIPPI
NOAA Chart: 11372 Latitude: 30° 1.6' N
USGS Quad: GULFPORTSOUTH Longitude: 89° 4.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5557 C 1979
MONUMENTATION: Survey Disk VM#: 10382
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is near the Coast Guard station at Gulfport Harbor, 216 feet (66
m) NW of Bench Mark NO 3 1969, 106 feet (32 m) NE of a flagpole in front of the
Coast Guard station, 85 feet (26 m) west of a concrete sea wall along the east
shore, 3.7 feet (1.1 m) north of the south curb of a median with rose garden in
front of the station, and 3.0 feet (0.9 m) SW of a palm tree in said median.
The bench mark is 0.3 foot (0.1 m) below ground level, crimped to a stainless
steel rod driven 50 feet (15 m) to substantial resistance, 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
PUBLICATION DATE: 08/20/1990
Station ID: 8745557 SUPERCEDED DATE: 04/21/2003
Name: GULFPORT HARBOR, MISSISSIPPI SOUND
MISSISSIPPI
NOAA Chart: 11372 Latitude: 30° 1.6' N
USGS Quad: GULFPORTSOUTH Longitude: 89° 4.9' W
T I D A L D A T U M S
Tidal datums at GULFPORT HARBOR, MISSISSIPPI SOUND based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: AUGUST-OCTOBER 1979
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8747437 BAY WAVELAND
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (09/13/1979) = 3.81
MEAN HIGHER HIGH WATER MHHW = 1.79
MEAN HIGH WATER MHW = 1.66
MEAN TIDE LEVEL MTL = 0.90
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 0.74
MEAN LOW WATER MLW = 0.14
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (09/12/1979) = -2.44
* NGVD reference based on elevations published in Quad 300892, 1984, and NOS
leveling of 1979.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
5557 A 1979 5.29 3.63
NO 1 1969 8.49 6.83
NO 2 1969 7.62 5.96
NO 3 1969 7.60 5.94
5557 B 1979 5.44 3.78
5557 C 1979 7.54 5.88
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 08/20/1990
Station ID: 8745557 SUPERCEDED DATE: 04/21/2003
Name: GULFPORT HARBOR, MISSISSIPPI SOUND
MISSISSIPPI
NOAA Chart: 11372 Latitude: 30° 1.6' N
USGS Quad: GULFPORTSOUTH Longitude: 89° 4.9' 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 (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 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.