U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8726978 PUBLICATION DATE: 01/06/2004
Name: BAILEYS BLUFF GULFSIDE
FL
NOAA Chart: 11410 Latitude: 28° 12.3' N ( 28.20500)
USGS Quad: TARPON SPRINGS Longitude: 82° 47.0' W ( -82.78330)
To reach the tidal bench marks from the intersection of U.S. Highway ALT 19 and
Anclote Boulevard, north of Tarpon Springs, proceed west on Anclote Boulevard
for 3.2 km (2.0 mi) to its end at Baileys Bluff Road, then turn left and proceed
north and east on Baileys Bluff Road for for 3.8 km (2.4 mi) to Gulfview Drive,
then proceed west along Gulfview Drive. The gage and staff were at the private
pier of the residence at 89 Gulfview Drive. The bench marks are along Gulfview
Drive and the seawall.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: BAILEYS BLUFF RM NO 1 1910
DESIGNATION: BAILEYS BLUFF RM 1
MONUMENTATION: Reference Mark disk VM#: 7684
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AL7479
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 28° 12.4' N ( 28.20670) LONGITUDE: 82° 46.9' W ( -82.78170)
The primary bench mark is a disk set flush in a concrete sea wall, WSW of
dwelling at 82 Gulfview Drive, 42 m (139 ft) SW of bench mark 6978 C 1976, 20 m
(66 ft) SW of the SW corner of the dwelling and 1 m (4 ft) west of a boat ramp.
NOTE:The bench mark has been reset by a private citizen.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8726978 PUBLICATION DATE: 01/06/2004
Name: BAILEYS BLUFF GULFSIDE
FL
NOAA Chart: 11410 Latitude: 28° 12.3' N ( 28.20500)
USGS Quad: TARPON SPRINGS Longitude: 82° 47.0' W ( -82.78330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6978 A 1976
DESIGNATION: 872 6978 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 7681
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7481
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 28° 12.4' N ( 28.20670) LONGITUDE: 82° 46.9' W ( -82.78170)
The bench mark is a disk set flush in a concrete pad near the SE corner of the
dwelling at 89 Gulfview Drive, 12.04 m (39.5 ft) NW of a railroad spike in the
center of the circle at the end of Gulfview Drive, and 0.21 m (0.7 ft) east of
the SE corner of the building.
BENCH MARK STAMPING: 6978 B 1976
DESIGNATION: 872 6978 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 7682
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7478
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 28° 12.4' N ( 28.20670) LONGITUDE: 82° 46.8' W ( -82.78000)
The bench mark is a disk located 17 m (57 ft) east of the SE corner of the
dwelling at 83 Gulfview Drive, 6.55 m (21.5 ft) NW of the centerline of Gulfview
Drive, and 0.24 m (0.8 ft) SE of a utility pole with a witness sign attached.
The bench mark is set at ground level, crimped to the top of a copper-coated
steel rod driven an unspecified depth to refusal, and encased in a PVC pipe with
concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8726978 PUBLICATION DATE: 01/06/2004
Name: BAILEYS BLUFF GULFSIDE
FL
NOAA Chart: 11410 Latitude: 28° 12.3' N ( 28.20500)
USGS Quad: TARPON SPRINGS Longitude: 82° 47.0' W ( -82.78330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6978 C 1976
DESIGNATION: 872 6978 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 7683
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7480
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 28° 12.4' N ( 28.20670) LONGITUDE: 82° 46.9' W ( -82.78170)
The bench mark is a disk located 82 m (269 ft) SSW of bench mark 6978 B 1976, 31
m (103 ft) SE of bench mark 6978 A 1976, 11 m (36 ft) north of the NE corner of
the garage and 5 m (16 ft) east of the centerline of the driveway at dwelling 82
Gulfview Drive, and 0.24 m (0.8 ft) north of a utility pole. The bench mark is
set at ground level, crimped to the top of a copper-coated steel rod driven an
unspecified depth to refusal, and encased in a PVC pipe with concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8726978 PUBLICATION DATE: 01/06/2004
Name: BAILEYS BLUFF GULFSIDE
FL
NOAA Chart: 11410 Latitude: 28° 12.3' N ( 28.20500)
USGS Quad: TARPON SPRINGS Longitude: 82° 47.0' W ( -82.78330)
T I D A L D A T U M S
Tidal datums at BAILEYS BLUFF GULFSIDE based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: March 1976 - March 1976
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 = 0.968
MEAN HIGH WATER MHW = 0.855
North American Vertical Datum NAVD88 = 0.640
MEAN SEA LEVEL MSL = 0.522
MEAN TIDE LEVEL MTL = 0.510
MEAN LOW WATER MLW = 0.165
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
BAILEYS BLUFF RM NO 1 1910 1.903 1.048
6978 A 1976 2.127 1.272
6978 B 1976 2.310 1.455
6978 C 1976 1.994 1.139
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8726978 PUBLICATION DATE: 01/06/2004
Name: BAILEYS BLUFF GULFSIDE
FL
NOAA Chart: 11410 Latitude: 28° 12.3' N ( 28.20500)
USGS Quad: TARPON SPRINGS Longitude: 82° 47.0' W ( -82.78330)
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.