U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
To reach the tidal bench marks from the intersection of U.S. Highway 19 and
State Road 60 (Gulf to Bay Boulevard), proceed approximately 10 km (6 mi) west
across Memorial Causeway to Causeway Boulevard, then across Gulfview Boulevard
to the public parking area for Big Pier 60. The bench marks are located in the
vicinity of the Clearwater Marina and the tide gage is located at the seaward
end of Big Pier 60 just east of the T-end.
T I D A L B E N C H M A R K S
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: LP 10 RM 1
DESIGNATION: LP 10 1 FLHD
MONUMENTATION: Survey disk VM#: 742
AGENCY: Florida Highway Department (FLHD) IDB PID#: AG7197
SETTING CLASSIFICATION: Massive retaining wall OPUS PID:
LATITUDE: 27° 58.6' N ( 27.97592) LONGITUDE: 82° 49.7' W ( -82.82789)
The primary bench mark is a survey disk set in a 0.46 m (1.51 ft) wide concrete
sea wall near the SW corner of the Clearwater Marina Yacht Basin, on the east
side of the T-intersection of Coronado Drive and Gulfview Boulevard, directly
underneath an iron handrail, 11.52 m (37.8 ft) east of the centerline of
Coronado Drive, and 0.3 m (1 ft) north of the curve in the sea wall.
BENCH MARK STAMPING: 6724 A 1978
DESIGNATION: 872 6724 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 745
AGENCY: National Ocean Survey (NOS) IDB PID#: AG7196
SETTING CLASSIFICATION: Concrete sea wall OPUS PID#: AG7196
LATITUDE: 27° 58.6' N ( 27.97658) LONGITUDE: 82° 49.7' W ( -82.82789)
The bench mark is a disk set flush in the concrete sea wall cap at the NW corner
of the Clearwater Marina, 11.43 m (37.5 ft) east of the centerline of Coronado
Drive, 4.57 m (14.99 ft) south of concrete pole 35 at the NW corner of the
Marina, and 0.15 m (0.49 ft) north of the handrail around the sidewalk at the
west end of the marina parking lot.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6724 R 2013
DESIGNATION: 872 6724 R
MONUMENTATION: Metal Rod VM#: 20655
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 27° 58.6' N ( 27.97700) LONGITUDE: 82° 49.3' W ( -82.82169)
The bench mark is located 77.65 m (257.7 ft) west of a light pole marked
'A/2/08', 13.7 m (44.9 ft) NNE of the centerline of an asphalt path on the south
side of the causeway, and 13.2 m (43.3 ft) SSE of a light pole marked 'A/2/06'.
The datum point is 10 cm (0.3 ft) below grade, being the top of a stainless
steel rod driven 6.7 m (22 ft) to refusal, encased in a NOS logo cap with a
concrete kickblock. The mark is surrounded by a concrete kick block, with a
standard NOS aluminum lid stamped '872 7624 R 2013', without a witness post due
to potential mowing damage.
BENCH MARK STAMPING: 6724 S 2013
DESIGNATION: 872 6724 S
MONUMENTATION: Tidal Station disk VM#: 20668
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 27° 58.6' N ( 27.97717) LONGITUDE: 82° 49.3' W ( -82.82236)
The bench mark is a disk set in the SE corner of a 5.19m (17 ft) x 4.46m (14.6
ft) concrete pad for a rest area with a drinking fountain and metal canopy,
65.3m (214.2 ft) west of a light pole marked 'A/2/06', 61.9 m (203.1 ft) east of
the easternmost end of a 1.5m (4.9 ft) tall metal rail on the northern edge of a
concrete foot traffic bridge, and 2.92m (9.6 ft) north of the centerline of an
asphalt path on the south side of causeway, flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6724 T 2016
DESIGNATION: 872 6724 T
MONUMENTATION: Tidal Station disk VM#: 21868
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete pier OPUS PID:
LATITUDE: 27° 58.7' N ( 27.97767) LONGITUDE: 82° 49.9' W ( -82.83211)
The bench mark is a disk set in the concrete pier deck of the big 60 pier on the
south side near the T intersection at the end of the pier, 8.41 m (27.6 ft) east
of the southeast corner of the T intersection of the pier, 4.60 m (15.1 ft)
south of the north edge of the fishing pier, and 0.3 m (1.0 ft) north of the
south edge of the fishing pier, directly adjacent to the NOS tidal gauging
station, being the high point of a standard brass NOS bench mark disc.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
T I D A L D A T U M S
Tidal datums at CLEARWATER BEACH, GULF OF MEXICO based on:
LENGTH OF SERIES: 16 YEARS
TIME PERIOD: 1/97-12/00,5/01-4/07,8/08-7/09,8/10-7/12,5/15-4/18
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:
HIGHEST OBSERVED WATER LEVEL (03/13/1993) = 2.061
MEAN HIGHER HIGH WATER MHHW = 0.836
MEAN HIGH WATER MHW = 0.733
North American Vertical Datum NAVD88 = 0.546
MEAN SEA LEVEL MSL = 0.450
MEAN TIDE LEVEL MTL = 0.444
MEAN LOW WATER MLW = 0.156
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/19/1977) = -0.783
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
LP 10 RM 1 1.707 0.974
6724 A 1978 1.746 1.013
6724 R 2013 1.560 0.827
6724 S 2013 1.949 1.216
6724 T 2016 4.546 3.813
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8726724 PUBLICATION DATE: 06/03/2020
Name: CLEARWATER BEACH, GULF OF MEXICO
FL
NOAA Chart: 11412 Latitude: 27° 58.7' N ( 27.97830)
USGS Quad: CLEARWATER Longitude: 82° 49.9' W ( -82.83170)
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.