U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 11/02/1987
Station ID: 8722481 SUPERCEDED DATE: 04/21/2003
Name: LOXAHATCHEE RIVER
FLORIDA
NOAA Chart: 11474 Latitude: 26° 58.2' N
USGS Quad: ROOD Longitude: 80° 7.5' W
To reach the tidal bench marks from the intersection of U.S. Highway 1 and
Tequesta Drive in Tequesta, proceed 1.6 miles (2.6 km) west on Tequesta Drive to
Country Club Road, then 1.1 miles (1.8 km) north on Country Club Road to North
Place, then 0.05 mile (0.08 km) south on North Place to Fairway North, then 0.3
mile (0.5 km) west on Fairway North to River Road, then 0.3 mile (0.5 km) NW on
River Road to its end at 347 River Road. The bench marks are located on the sea
wall at 347 River Road. The tide gage and staff were located on the dock at 347
River Road.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1972
MONUMENTATION: Survey Disk VM#: 5511
AGENCY: PID#: AD6235
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the concrete sea wall at 347 River Road, 68.5
feet (20.9 m) SE of Bench Mark NO 2 1972, 61.8 feet (18.8 m) west of the SW
corner of the house, 55.0 feet (16.8 m) west of the centerline of a wooden pier,
and 36 feet (11.0 m) south of a large tree.
BENCH MARK STAMPING: NO 2 1972
MONUMENTATION: Survey Disk VM#: 5512
AGENCY: PID#: AD6234
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the concrete sea wall at 347 River Road, 91.3
feet (27.8 m) west of the west side of the garage, 82.0 feet (25.0 m) south of
Bench Mark NO 3 1972, 68.5 feet (20.9 m) NW of Bench Mark NO 1 1972, and 32.9
feet (10.0 m) WNW of a large tree.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 11/02/1987
Station ID: 8722481 SUPERCEDED DATE: 04/21/2003
Name: LOXAHATCHEE RIVER
FLORIDA
NOAA Chart: 11474 Latitude: 26° 58.2' N
USGS Quad: ROOD Longitude: 80° 7.5' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 3 1972
MONUMENTATION: Survey Disk VM#: 5513
AGENCY: PID#: AD6233
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the concrete sea wall at 347 River Road, 82.0
feet (25.0 m) north of Bench Mark NO 2 1972, 77.5 feet (23.6 m) south of Bench
Mark NO 4 1972, and 61.4 feet (18.7 m) WNW of the NW corner of the guest house.
BENCH MARK STAMPING: NO 4 1972
MONUMENTATION: Survey Disk VM#: 5514
AGENCY: PID#: AD6232
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the concrete sea wall at 347 River Road, 89.0
feet (27.1 m) NW of the NW corner of the guest house, 77.5 feet (23.6 m) north
of Bench Mark NO 3 1972, and 72.2 feet (22.0 m) south of Bench Mark NO 5 1972.
BENCH MARK STAMPING: NO 5 1972
MONUMENTATION: Survey Disk VM#: 5515
AGENCY: PID#: AD6231
SETTING CLASSIFICATION: Concrete Sea Wall
The bench mark is set flush in the concrete sea wall at 347 River Road, 72.2
feet (22.0 m) north of Bench Mark NO 4 1972, 33.4 feet (10.2 m) south of the
north end of the sea wall, and 17.0 feet (5.2 m) south of the centerline of a
wooden finger pier.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 11/02/1987
Station ID: 8722481 SUPERCEDED DATE: 04/21/2003
Name: LOXAHATCHEE RIVER
FLORIDA
NOAA Chart: 11474 Latitude: 26° 58.2' N
USGS Quad: ROOD Longitude: 80° 7.5' W
T I D A L D A T U M S
Tidal datums at LOXAHATCHEE RIVER based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: DECEMBER 1972 & JANUARY 1973
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8722557 NORTH PALM BEACH
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (01/13/1973) = 3.25
MEAN HIGHER HIGH WATER MHHW = 2.28
MEAN HIGH WATER MHW = 2.14
MEAN TIDE LEVEL MTL = 1.15
MEAN LOW WATER MLW = 0.16
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (12/07/1972) = -0.41
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 1 1972 4.35 2.21
NO 2 1972 4.12 1.98
NO 3 1972 4.19 2.05
NO 4 1972 4.22 2.08
NO 5 1972 4.22 2.08
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 11/02/1987
Station ID: 8722481 SUPERCEDED DATE: 04/21/2003
Name: LOXAHATCHEE RIVER
FLORIDA
NOAA Chart: 11474 Latitude: 26° 58.2' N
USGS Quad: ROOD Longitude: 80° 7.5' 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.