U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8726905 PUBLICATION DATE: 01/06/2004
Name: TARPON SPRINGS, ANCLOTE RIVER
FL
NOAA Chart: 11412 Latitude: 28° 9.6' N ( 28.16000)
USGS Quad: TARPON SPRINGS Longitude: 82° 46.1' W ( -82.76830)
To reach the tidal bench marks from the north end of the bridge over Anclote
River in Tarpon Springs, proceed 0.2 km (0.1 mi) along U.S. Highway ALT 19, then
turn left and proceed 1.0 km (0.6 mi) west along Pinellas County Route 47, then
0.3 km (0.2 mi) west along a dirt road to the Bradley residence. The bench
marks are between Anclote Road and the river. The gage and staff were north of
the Bradley residence at the wood pier west of the Linger Longer trailer park.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO I
DESIGNATION: 872 6907 TIDAL 1
ALIAS: 872 6905 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 7647
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AL6197
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 9.6' N ( 28.16000) LONGITUDE: 82° 46.0' W ( -82.76670)
The primary bench mark is a disk set in the top of a concrete monument, 19 m (63
ft) SE of the SE corner of the Bradley's two story frame house, 1 m (3 ft) south
of the SW corner of a garage, and 0.06 m (0.2 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8726905 PUBLICATION DATE: 01/06/2004
Name: TARPON SPRINGS, ANCLOTE RIVER
FL
NOAA Chart: 11412 Latitude: 28° 9.6' N ( 28.16000)
USGS Quad: TARPON SPRINGS Longitude: 82° 46.1' W ( -82.76830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO II
DESIGNATION: 872 6907 TIDAL 2
ALIAS: 872 6905 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 7648
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AL6199
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 9.6' N ( 28.16000) LONGITUDE: 82° 46.0' W ( -82.76670)
The bench mark is a disk set in the top of a concrete monument, 3.66 m (12.0 ft)
SW of the SW corner of the Bradley's two story frame house, 0.06 m (0.2 ft)
north of the north edge of a east-west sidewalk, 0.06 m (0.2 ft) east of the
east edge of a north-south sidewalk, and 0.06 m ( 0.2 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8726905 PUBLICATION DATE: 01/06/2004
Name: TARPON SPRINGS, ANCLOTE RIVER
FL
NOAA Chart: 11412 Latitude: 28° 9.6' N ( 28.16000)
USGS Quad: TARPON SPRINGS Longitude: 82° 46.1' W ( -82.76830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO III
DESIGNATION: 872 6907 TIDAL 3
ALIAS: 872 6905 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 7649
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AL6198
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 9.6' N ( 28.16000) LONGITUDE: 82° 46.0' W ( -82.76670)
The bench mark is a disk set in the top of a concrete monument, 76 m (250 ft)
south of the south face of the Bradley's two story frame house, 55 m (180 ft)
south of Bench Mark No II, 8.23 m (27.0 ft) north of the north bank of the
Anclote River, 6.40 m (21.0 ft) south of a triangular blazed 0.3 (1 ft) diameter
pine tree, 5.64 m (18.5 ft) east of a triangular blazed 0.37 m (1.2 ft) diameter
pine tree, 0.40 m (1.3 ft) north of a witness post, 0.03 m (0.1 ft) above ground
level. NOTE: Mark not found in 1990 by US Power Squadron. Mark should be used
with caution as it is leaning.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8726905 PUBLICATION DATE: 01/06/2004
Name: TARPON SPRINGS, ANCLOTE RIVER
FL
NOAA Chart: 11412 Latitude: 28° 9.6' N ( 28.16000)
USGS Quad: TARPON SPRINGS Longitude: 82° 46.1' W ( -82.76830)
T I D A L D A T U M S
Tidal datums at TARPON SPRINGS, ANCLOTE RIVER based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: October 1975 - October 1975
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8726924 ANCLOTE RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.900
MEAN HIGH WATER MHW = 0.790
North American Vertical Datum NAVD88 = 0.537
MEAN SEA LEVEL MSL = 0.484
MEAN TIDE LEVEL MTL = 0.472
MEAN LOW WATER MLW = 0.154
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO I 3.273 2.483
NO II 2.578 1.788
NO III 2.258 1.468
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8726905 PUBLICATION DATE: 01/06/2004
Name: TARPON SPRINGS, ANCLOTE RIVER
FL
NOAA Chart: 11412 Latitude: 28° 9.6' N ( 28.16000)
USGS Quad: TARPON SPRINGS Longitude: 82° 46.1' W ( -82.76830)
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.