U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 11/02/1984
Station ID: 8727328 SUPERCEDED DATE: 04/21/2003
Name: OZELLO NORTH, CRYSTAL RIVER
FLORIDA
NOAA Chart: 11409 Latitude: 28° 51.8' N
USGS Quad: OZELLO Longitude: 82° 40.0' W
To reach the tidal bench marks from the intersection of U.S. Highway 19 and
State Highway C-494 in Crystal River, Florida, proceed west on C-494 9.3 miles
(15.0 km) to the last causeway before the road ends at a T intersection. The
bench marks are located along the causeway. The tide gage and staff were
located on the State of Florida wharf.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 7328 D 1978
MONUMENTATION: Survey Disk VM#: 7783
AGENCY: PID#: AL7743
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is located 338 feet (103 m) south of Bench Mark 7328 B 1978 along
C-494, 86 feet (26 m) NW of the NW corner of a yellow block building owned by
Clifton Cove Marina, 17.8 feet (5.4 m) west of the centerline of State Road
C-494 and 2.8 feet (0.9 m) east of power pole #037. The bench mark is crimped
to the top of a stainless steel rod driven 3 feet (1 m) to refusal, and encased
in PVC pipe and a concrete kickblock.
BENCH MARK STAMPING: 7328 A 1978
MONUMENTATION: Survey Disk VM#: 7780
AGENCY: PID#: AL7745
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set in the concrete foundation of the causeway, 74 feet (23 m)
north of Bench Mark 7328 B 1978, 17 feet (5.2 m) west of the centerline of State
Highway C-494 and 2.5 feet (0.8 m) east of the west edge of the causeway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 11/02/1984
Station ID: 8727328 SUPERCEDED DATE: 04/21/2003
Name: OZELLO NORTH, CRYSTAL RIVER
FLORIDA
NOAA Chart: 11409 Latitude: 28° 51.8' N
USGS Quad: OZELLO Longitude: 82° 40.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7328 B 1978
MONUMENTATION: Survey Disk VM#: 7781
AGENCY: PID#: AL7744
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set in the concrete foundation of the east edge of the
causeway, 206 feet (63 m) south of Bench Mark 7328 A 1978, 109 feet (33 m) south
of the power pole near the center of the causeway, 15.3 feet (4.7 m) east of the
centerline of C-494 and 1.9 feet (0.6 m) west of the east edge of the causeway.
BENCH MARK STAMPING: 7328 C 1978
MONUMENTATION: Survey Disk VM#: 7782
AGENCY: PID#: AL7742
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set in the top of a concrete monument, 262 feet (80 m) south
of 7328 D 1978 on C-494, 65 feet (20 m) SW of the NW corner of a small log
cabin, 32 feet (10 m) east of the centerline of C-494 and 2.9 feet (0.9 m) NW of
power pole #013.
BENCH MARK STAMPING: 7328 E 1978
MONUMENTATION: Survey Disk VM#: 7784
AGENCY: PID#: AL7741
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is located 467 feet (142 m) south of Bench Mark 7328 C 1978,
along State Road C-494, 102 feet (31 m) north of a sand track driveway leading
to Rt 1 Box 302, 21.1 feet (6.4 m) NE of the centerline of C-494, 17.8 feet (5.4
m) south of the centerline of a gravel driveway leading to Route 1 Box 301 and
5.8 feet (1.8 m) south of power pole #112. The bench mark is crimped to the top
of a stainless steel rod driven 5 feet (2 m) to refusal, and encased in PVC pipe
and a concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 11/02/1984
Station ID: 8727328 SUPERCEDED DATE: 04/21/2003
Name: OZELLO NORTH, CRYSTAL RIVER
FLORIDA
NOAA Chart: 11409 Latitude: 28° 51.8' N
USGS Quad: OZELLO Longitude: 82° 40.0' W
T I D A L D A T U M S
Tidal datums at OZELLO NORTH, CRYSTAL RIVER based on:
LENGTH OF SERIES: 6 MONTHS
TIME PERIOD: JUNE-DECEMBER 1978
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8727520 CEDAR KEY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (12/05/1978) = 3.88
MEAN HIGHER HIGH WATER MHHW = 2.03
MEAN HIGH WATER MHW = 1.69
MEAN TIDE LEVEL MTL = 0.93
MEAN LOW WATER MLW = 0.16
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (01/04/1979) = -1.10
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
7328 D 1978 4.33 2.64
7328 A 1978 3.34 1.65
7328 B 1978 5.90 4.21
7328 C 1978 2.99 1.30
7328 E 1978 3.00 1.31
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 11/02/1984
Station ID: 8727328 SUPERCEDED DATE: 04/21/2003
Name: OZELLO NORTH, CRYSTAL RIVER
FLORIDA
NOAA Chart: 11409 Latitude: 28° 51.8' N
USGS Quad: OZELLO Longitude: 82° 40.0' 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.