U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 1 of 5
Station ID: 8728786 PUBLICATION DATE: 10/30/2003
Name: ELEVEN MILE, ST. VINCENT SOUND
FLORIDA
NOAA Chart: 11401 Latitude: 29ø 42.4' N
USGS Quad: INDIAN PASS Longitude: 85ø 9.2' W
To reach the tidal bench marks from the Franklin County Courthouse in
Appalachicola proceed west on U.S. Highway 98 for 13.0 km (8.1 mi) to the
Y-junction of County Road C-30, then west on County Road C-30 for 4.8 km (3.0
mi) to the dirt drive to the Eleven Mile Fishery, then south on the drive for
0.3 km (0.2 mi) to the fish house. The bench marks are along County Road C-30
and the drive to the fish house. The tide gage and staff were located at the
Eleven Mile Fishery dock.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8786 A 1977
DESIGNATION: 872 8786 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 9884
AGENCY: National Ocean Survey (NOS) PID#: AS0872
SETTING CLASSIFICATION: Copper-clad steel rod
The primary bench mark is a disk located 17.68 m (58.0 ft) SE of the NE corner
of the easterly dock, 7.0 m (23.0 ft) ENE of the centerline the dirt road, 1.98
m (6.5 ft) SE of utility pole No. 56X 2661R, and 0.6 m (2 ft) west of a witness
post. The bench mark is set at ground level, crimped to the top of a
copper-clad steel rod driven 14.63 m (48.0 ft), and encased in a PVC pipe and
concrete kickblock.
BENCH MARK STAMPING: 8786 B 1977
DESIGNATION: 872 8786 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 9885
AGENCY: National Ocean Survey (NOS) PID#: AS0871
SETTING CLASSIFICATION: Concrete monument
The bench mark is a disk set in the top of a concrete monument, 103 m (337 ft)
NW of bench mark 8786 A 1977, 23.62 m (77.5 ft) SSW of powerline pole No. 6 X
860R with a transformer, 13.7 m (45 ft) WSW of a 2 m (5 ft) diameter oak tree,
4.57 m (15.0 ft) west of the centerline of the dirt road, 0.52 m (1.7 ft) SE of
a witness post, 3 m (10 ft) NNW of a 0.43 m (1.4 ft) diameter palm tree, and at
ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8728786 PUBLICATION DATE: 10/30/2003
Name: ELEVEN MILE, ST. VINCENT SOUND
FLORIDA
NOAA Chart: 11401 Latitude: 29ø 42.4' N
USGS Quad: INDIAN PASS Longitude: 85ø 9.2' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8786 C 1977
DESIGNATION: 872 8786 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 9886
AGENCY: National Ocean Survey (NOS) PID#: AS0870
SETTING CLASSIFICATION: Concrete monument
The bench mark is a disk set in the top of a concrete monument, 90 m (296 ft)
north of bench mark 8786 B 1977, 12.80 m (42.0 ft) SE of powerline pole No. 56X
1859R, 10.36 m (34.0 ft) NW of a 0.46 m (1.5 ft) diameter palm tree, 7.92 m
(26.0 ft) ENE of the centerline of the dirt road, 1.22 m (4.0 ft) WNW of a
witness post, and at ground level.
BENCH MARK STAMPING: 8786 D 1977
DESIGNATION: 872 8786 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 9887
AGENCY: National Ocean Survey (NOS) PID#: AS0869
SETTING CLASSIFICATION: Copper-clad steel rod
The bench mark is a disk located 82 m (268 ft) north of bench mark 8766 C 1977,
26.21 m (86.0 ft) SSE of the centerline of County Road C-30, 7.32 m (24.0 ft)
ENE of the centerline of the drive to Eleven Mile Fishery, 3.14 (10.3 ft) WSW of
SW corner of an abandoned concrete block building, 3.35 m (11.0 ft) NNW of
powerline pole No. 56X 1790R, and 0.55 m (1.8 ft) WSW of a witness post. The
bench mark is set at ground level, crimped to the top of a copper-coated steel
rod driven 4.72 m (15.5 ft), and encased in a PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8728786 PUBLICATION DATE: 10/30/2003
Name: ELEVEN MILE, ST. VINCENT SOUND
FLORIDA
NOAA Chart: 11401 Latitude: 29ø 42.4' N
USGS Quad: INDIAN PASS Longitude: 85ø 9.2' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8786 E 1977
DESIGNATION: 872 8786 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 9888
AGENCY: National Ocean Survey (NOS) PID#: AS0520
SETTING CLASSIFICATION: Concrete monument
The bench mark is a disk set in a concrete monument, 58.8 m (193.0 ft) ENE of
the junction of the dirt drive and County Road C-30, 11.77 m (38.6 ft) NNW of
the centerline of County Road C-30, 6.7 m (22.0 ft) SE of a powerline pole, 0.49
m (1.6 ft) SE of a witness post, and at ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8728786 PUBLICATION DATE: 10/30/2003
Name: ELEVEN MILE, ST. VINCENT SOUND
FLORIDA
NOAA Chart: 11401 Latitude: 29ø 42.4' N
USGS Quad: INDIAN PASS Longitude: 85ø 9.2' W
T I D A L D A T U M S
Tidal datums at ELEVEN MILE, ST. VINCENT SOUND based on:
LENGTH OF SERIES: 6 MONTHS
TIME PERIOD: December 1977 - May 1978
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8729840 PENSACOLA, PENSACOLA BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER (MHHW) = 0.509
MEAN HIGH WATER (MHW) = 0.468
MEAN TIDE LEVEL (MTL) = 0.297
NORTH AMERICAN VERTICAL DATUM-1988 (NAVD) = 0.280
MEAN SEA LEVEL (MSL) = 0.274
MEAN LOW WATER (MLW) = 0.126
MEAN LOWER LOW WATER (MLLW) = 0.000
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8786 A 1977 1.000 0.532
8786 B 1977 1.980 1.512
8786 C 1977 1.715 1.247
8786 D 1977 2.364 1.896
8786 E 1977 3.072 2.604
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8728786 PUBLICATION DATE: 10/30/2003
Name: ELEVEN MILE, ST. VINCENT SOUND
FLORIDA
NOAA Chart: 11401 Latitude: 29ø 42.4' N
USGS Quad: INDIAN PASS Longitude: 85ø 9.2' 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.