U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 01/13/1989
Station ID: 8726833 SUPERCEDED DATE: 04/21/2003
Name: PALM HARBOR, SUTHERLAND BAYOU
FLORIDA
NOAA Chart: 11412 Latitude: 28° 5.1' N
USGS Quad: DUNEDIN Longitude: 82° 46.2' W
To reach the tidal bench marks from the intersection of U.S. Highway Alt. 19
(10th Street) and Delaware Avenue in Palm Harbor, proceed north on U.S. Highway
Alt. 19 for about 0.5 mile (0.8 km) to a drive leading to Palm Harbor Fishing
Lodge, turn left and continue past the railroad tracks to the waterfront. The
bench marks are located along U.S. Highway Alt. 19 between Delaware Avenue and
the drive. The tide gage and staff were located on a dock at the Palm Harbor
Fishing Lodge.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 6833 A
MONUMENTATION: Survey Disk VM#: 7622
AGENCY: PID#: AL7394
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is on the west side of U.S. Highway Alt. 19, north of Missouri
Avenue, about 0.1 mile (0.2 km) north of Bench Mark OZONA F, 34.5 feet (10.5 m)
west of the centerline of U.S. Highway Alt. 19, 29.5 feet (9.0 m) east of the
centerline of the railroad tracks, and 8.3 feet (2.5 m) south of utility pole
#12A-5811R with witness sign. The bench mark is 0.3 foot (0.1 m) below the
ground, crimped to a copper-clad steel rod driven an unspecified depth, and
encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 6833 B 1976
MONUMENTATION: Survey Disk VM#: 7620
AGENCY: PID:
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is on the west side of U.S. Highway Alt. 19, north of Missouri
Avenue, about 0.1 mile (0.2 km) NNE of Bench Mark 6833 C 1976, 34.7 feet (10.6
m) east of the centerline of the railroad tracks, 28.3 feet (8.6 m) west of the
centerline of U.S. Highway Alt. 19, and 1.4 feet (0.4 m) south of utility pole
#12A-5805R with witness sign. The bench mark is 0.5 foot (0.2 m) below the
ground, crimped to a copper-clad steel rod driven an unspecified depth, 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
PUBLICATION DATE: 01/13/1989
Station ID: 8726833 SUPERCEDED DATE: 04/21/2003
Name: PALM HARBOR, SUTHERLAND BAYOU
FLORIDA
NOAA Chart: 11412 Latitude: 28° 5.1' N
USGS Quad: DUNEDIN Longitude: 82° 46.2' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6833 C 1976
MONUMENTATION: Survey Disk VM#: 7621
AGENCY: PID#: AL7393
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is at the intersection of U.S. Highway Alt. 19 and Missouri
Avenue, about 0.7 mile (1.1 km) NE of Bench Mark OZONA G, 35 feet (11 m) NW of
the centerline of U.S. Highway Alt. 19, 25.7 feet (7.8 m) SE of the centerline
of the railroad tracks, and 21 feet (6 m) SW of the centerline of Missouri
Avenue. The bench mark is 0.2 foot (0.1 m) below the ground, crimped to a
copper-clad steel rod driven an unspecified depth to refusal, and encased in a
PVC pipe and concrete kickblock.
BENCH MARK STAMPING: OZONA F
MONUMENTATION: Survey Disk VM#: 7623
AGENCY: PID#: AL0280
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in the top of a concrete monument on the east side of U.S.
Highway Alt. 19, north of Missouri Avenue, 41 feet (12 m) SW of the NW corner of
a billboard, 32.2 feet (9.8 m) NE of the centerline of U.S. Highway Alt. 19,
19.9 feet (6.1 m) SW of th SE corner of the billboard, 5.2 feet (1.6 m) NE
of a 1.2-foot (0.4 m) diameter palm tree, and level with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 01/13/1989
Station ID: 8726833 SUPERCEDED DATE: 04/21/2003
Name: PALM HARBOR, SUTHERLAND BAYOU
FLORIDA
NOAA Chart: 11412 Latitude: 28° 5.1' N
USGS Quad: DUNEDIN Longitude: 82° 46.2' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: OZONA G
MONUMENTATION: Survey Disk VM#: 7624
AGENCY: PID#: AL0281
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in the top of a concrete monument at the intersection of
Delaware Avenue and U.S. Highway Alt. 19, 48.7 feet (14.8 m) south of the
centerline of Delaware Avenue, 42 feet (13 m) NW of a 2-foot (1 m) diameter pine
tree, 26.5 feet (8.1 m) east of the centerline of U.S. Highway Alt. 19, 2.0 feet
(0.6 m) NW of a 1.2-foot (0.4 m) diameter palm tree, and level with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 01/13/1989
Station ID: 8726833 SUPERCEDED DATE: 04/21/2003
Name: PALM HARBOR, SUTHERLAND BAYOU
FLORIDA
NOAA Chart: 11412 Latitude: 28° 5.1' N
USGS Quad: DUNEDIN Longitude: 82° 46.2' W
T I D A L D A T U M S
Tidal datums at PALM HARBOR, SUTHERLAND BAYOU based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: MARCH 1976
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8726761 DUNEDIN
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (03/17/1976) = 3.59
MEAN HIGHER HIGH WATER MHHW = 3.06
MEAN HIGH WATER MHW = 2.69
MEAN TIDE LEVEL MTL = 1.63
MEAN LOW WATER MLW = 0.57
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (02/25/1976) = -1.04
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
6833 A 4.52 1.83
6833 B 1976 9.38 6.69
6833 C 1976 13.21 10.52
OZONA F 12.58 9.89
OZONA G 18.44 15.75
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 01/13/1989
Station ID: 8726833 SUPERCEDED DATE: 04/21/2003
Name: PALM HARBOR, SUTHERLAND BAYOU
FLORIDA
NOAA Chart: 11412 Latitude: 28° 5.1' N
USGS Quad: DUNEDIN Longitude: 82° 46.2' 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 (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.