U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8727306 PUBLICATION DATE: 05/20/2004
Name: OZELLO
FL
NOAA Chart: 11409 Latitude: 28° 49.5' N ( 28.82500)
USGS Quad: OZELLO Longitude: 82° 39.5' W ( -82.65830)
To reach the tidal bench marks from the post office in Homosassa Springs,
proceed north on Highway 19 for 5.5 km (3.4 mi) to its intersection with West
Ozello Trail (County Road C-494), then turn left and proceed west on West Ozello
Trail for 8.7 km (5.4 mi) to South John Brown Drive, then turn left and proceed
south on South John Brown Drive for 1.0 km (0.6 mi) to a wooden pier at the end
of the road. The bench marks are located along South John Brown Drive. The
tide gage and staff were located on the pier at the end of the drive.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 7306 A 1978
DESIGNATION: 872 7306 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 7775
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7750
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID:
LATITUDE: 28° 49.5' N ( 28.82500) LONGITUDE: 82° 39.4' W ( -82.65670)
NOTE: The bench mark was destroyed sometime after 1985. The primary bench
mark was a disk located 5.43 m (17.8 ft) east of the centerline of South John
Brown Drive, 3.35 m (11.0 ft) west of a north-south chain link fence, and 0.79 m
(2.6 ft) NE of a powerline pole with a witness sign. The bench mark is crimped
to the top of a galvanized steel rod driven 2.4 m (8.0 ft) to refusal, and
encased in a PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8727306 PUBLICATION DATE: 05/20/2004
Name: OZELLO
FL
NOAA Chart: 11409 Latitude: 28° 49.5' N ( 28.82500)
USGS Quad: OZELLO Longitude: 82° 39.5' W ( -82.65830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7306 C 1978
DESIGNATION: 872 7306 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 7777
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7748
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID:
LATITUDE: 28° 49.7' N ( 28.82830) LONGITUDE: 82° 39.4' W ( -82.65670)
The bench mark is a disk located along the west side of South John Brown Drive,
149 m (490 ft) north of bench mark 7306 B 1978, 18.59 m (61.0 ft) north of the
centerline of Brookview Lane, 9.75 m (32.0 ft) south of the centerline of a
grass track driveway, 4.42 m (14.5 ft) west of the centerline of the paved road,
and 0.94 m (3.1 ft) east of a powerline pole with a witness sign attached. The
bench mark is crimped to the top of a galvanized steel rod driven 6.1 m (20 ft)
to refusal, and encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 7306 D 1978
DESIGNATION: 872 7306 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 7778
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7747
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 49.9' N ( 28.83170) LONGITUDE: 82° 39.4' W ( -82.65670)
The bench mark is a disk set in the top of a concrete monument located between 2
palm trees at the south end of a picnic area, 0.3 km (0.2 mi) south of the
junction of South John Brown Road and West Ozello Trail (County Road C-494),
27.43 m (90.0 ft) east of the centerline of South John Brown Road, 4.27 m (14.0
ft) from the centerline of the dirt drive through the picnic area, 0.15 m (0.5
ft) from a metal witness post, and 0.06 m (0.02 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8727306 PUBLICATION DATE: 05/20/2004
Name: OZELLO
FL
NOAA Chart: 11409 Latitude: 28° 49.5' N ( 28.82500)
USGS Quad: OZELLO Longitude: 82° 39.5' W ( -82.65830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7306 E 1978
DESIGNATION: 872 7306 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 7779
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7746
SETTING CLASSIFICATION: Concrete monument OPUS PID#: AL7746
LATITUDE: 28° 50.0' N ( 28.83330) LONGITUDE: 82° 39.3' W ( -82.65500)
The bench mark is a disk set in the top of a concrete monument at the NE corner
of a picnic area, NNE of bench mark 7306 D 1978, 34.14 m (112.0 ft) east of the
centerline of the paved road, 4.57 m (15.0 ft) NE of the dirt drive through the
picnic area, 3 m (10 ft) south of the marshline, 0.91 m (3.0 ft) north of a 0.24
m (0.8 ft) diameter palm tree, 0.52 m (1.7 ft) SW of a metal witness post, and
0.03 m (0.1 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8727306 PUBLICATION DATE: 05/20/2004
Name: OZELLO
FL
NOAA Chart: 11409 Latitude: 28° 49.5' N ( 28.82500)
USGS Quad: OZELLO Longitude: 82° 39.5' W ( -82.65830)
T I D A L D A T U M S
Tidal datums at OZELLO based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: October 1978 - November 1978
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8727520 CEDAR KEY, GULF OF MEXICO
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.226
MEAN HIGH WATER MHW = 0.178
North American Vertical Datum NAVD88 = 0.143
MEAN SEA LEVEL MSL = 0.108
MEAN TIDE LEVEL MTL = 0.104
MEAN LOW WATER MLW = 0.030
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
7306 A 1978 0.856 0.678
7306 C 1978 1.036 0.858
7306 D 1978 0.670 0.492
7306 E 1978 0.624 0.446
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8727306 PUBLICATION DATE: 05/20/2004
Name: OZELLO
FL
NOAA Chart: 11409 Latitude: 28° 49.5' N ( 28.82500)
USGS Quad: OZELLO Longitude: 82° 39.5' W ( -82.65830)
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.