U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 08/01/1984
Station ID: 8729329 SUPERCEDED DATE: 04/21/2003
Name: CHOCTAWHATCHEE RIVER
FLORIDA
NOAA Chart: 11388 Latitude: 30° 23.8' N
USGS Quad: BUNKER Longitude: 86° 5.3' W
To reach the tidal bench marks from the intersection of U.S. Highway 98 and a
dirt drive leading north on the east side of Peach Creek; follow the dirt drive
north from the sign which advertises Bunker Island Estates, to the ferry at the
end of the road which crosses the Intracoastal Waterway. Continue north from
the north bank of the ICWW to the residential area of Bunker Island, the dirt
drive will turn east and the bench marks are located on both sides of the dirt
drive in the vicinity of an A-frame residence owned by Mr. Olin Chesire. The
tide gage and staff were located on the end of the wood dock behind the A-frame
residence.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9329 A 1977
MONUMENTATION: Survey Disk VM#: 10075
AGENCY: PID#: BG4631
SETTING CLASSIFICATION: Concrete Post
The bench mark is set flush in the top of a concrete post, 73 feet (22 m) north
of the centerline of the east-west dirt drive, 35 feet(11 m) SSE of the
easternmost end of the dock of a private residence, 25 feet (8 m) east of the NE
corner of the large A-frame residence and 1.2 feet (0.4 m) north of the NW
corner of the small A-fram shed that is east of the large A-frame residence.
The bench
BENCH MARK STAMPING: 9329 B 1977
MONUMENTATION: Survey Disk VM#: 10076
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Post
The bench mark is set flush in the top of a concrete post 5 feet (2 m) deep, 170
feet (52 m) ESE of Bench Mark 9329 C 1977, 46.3 feet (14.1 m) south of the SW
corner ofthe white block house on the east side of the A-Frame, 11 feet (3 m)
south of the centerline of the east-west dirt drive and 6 feet (2 m) north of a
power pole with a witness sign. The bench mark is flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 08/01/1984
Station ID: 8729329 SUPERCEDED DATE: 04/21/2003
Name: CHOCTAWHATCHEE RIVER
FLORIDA
NOAA Chart: 11388 Latitude: 30° 23.8' N
USGS Quad: BUNKER Longitude: 86° 5.3' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9329 C 1977
MONUMENTATION: Survey Disk VM#: 10077
AGENCY: PID#: BG4632
SETTING CLASSIFICATION: Concrete Post
The bench mark is set flush in the top of a concrete post 5 feet (2 m) deep, 212
feet (65 m) ENE of Bench Mark 9329 D 1977, 10.4 feet (3.2 m) north of the
centerline of the east-west dirt drive and 1.7 feet (0.5 m) ESE of a power pole
with a witness sign. The bench mark is flush with the ground.
BENCH MARK STAMPING: 9329 D 1977
MONUMENTATION: Survey Disk VM#: 10078
AGENCY: PID#: BG4633
SETTING CLASSIFICATION: Concrete Post
The bench mark is set flush in the top of a concrete post 4.8 feet (2 m) deep,
50 feet (15 m) SSE of the SE corner of the black house on the north side of the
dirt drive, 12 feet (4 m) south of the centerline of the east-west dirt drive,
and 5 feet (2 m) north of the power pole. The bench mark is flush with the
ground.
BENCH MARK STAMPING: 9329 E 1977
MONUMENTATION: Survey Disk VM#: 10079
AGENCY: PID#: BG4630
SETTING CLASSIFICATION: Concrete Post
The bench mark is set flush in the top of a 4.6 feet (1.4 m) concrete post, 207
feet (6.3 m) ENE of Bench Mark 9329 B 1977, 16 feet (5 m) east of the drive
leading north to the easternmost house on the drive, 11.3 feet (3.4 m) north of
the centerline of the east-west dirt drive and 5.2 feet (1.6 m) SW of a power
pole with a witness sign. The bench mark is flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 08/01/1984
Station ID: 8729329 SUPERCEDED DATE: 04/21/2003
Name: CHOCTAWHATCHEE RIVER
FLORIDA
NOAA Chart: 11388 Latitude: 30° 23.8' N
USGS Quad: BUNKER Longitude: 86° 5.3' W
T I D A L D A T U M S
Tidal datums at CHOCTAWHATCHEE RIVER based on:
LENGTH OF SERIES: 4 MONTHS
TIME PERIOD: JULY-OCTOBER 1977
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8729840 Pensacola
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (09/07/1977) = 2.08
MEAN HIGHER HIGH WATER MHHW = 0.55
MEAN HIGH WATER MHW = 0.49
MEAN TIDE LEVEL MTL = 0.27
MEAN LOW WATER MLW = 0.05
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (12/08/1977) = -0.72
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
9329 A 1977 4.22 3.73
9329 B 1977 4.42 3.93
9329 C 1977 3.79 3.30
9329 D 1977 4.28 3.79
9329 E 1977 5.51 5.02
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 08/01/1984
Station ID: 8729329 SUPERCEDED DATE: 04/21/2003
Name: CHOCTAWHATCHEE RIVER
FLORIDA
NOAA Chart: 11388 Latitude: 30° 23.8' N
USGS Quad: BUNKER Longitude: 86° 5.3' 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.