U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
To reach the tidal bench marks from the intersection of State Highways A1A and
814 in Pompano Beach, proceed 3.9 km (2.4 mi) north on State Highway A1A to a
black-topped road just north of the bridge over Hillsboro Inlet, then turn right
and proceed 0.08 km (0.05 mi) east on the black-topped road to the entrance gate
of the Hillsboro Inlet Private Club, then continue 0.24 km (0.15 mi) past the
gate to the U.S. Coast Guard Station. The bench marks are in the vicinity of
the Coast Guard station. The orifice of the tide gage was located east of the
south end of a jetty that runs south from the SE end of the peninsula and
strapped to the bottom of a 0.30 m (1.0 ft) pile used as the North Inlet lighted
channel marker 2. The tide staff was located on a piling about 5 m (15 ft) NE
of the south end of the Coast Guard Light Station pier (the same staff was used
for both stations 872 2861 and 872 2862).
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: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: Z 311 1970
DESIGNATION: Z 311
ALIAS: 12.641
MONUMENTATION: Bench Mark disk VM#: 5679
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AD2605
SETTING CLASSIFICATION: Concrete flagpole base OPUS PID:
LATITUDE: 26° 15.6' N ( 26.26000) LONGITUDE: 80° 4.8' W ( -80.08000)
The primary bench mark is a disk set in the top of the SE corner of the concrete
flagpole base on the U.S. Coast Guard station, 19 m (64 ft) east of the
centerline of the driveway, 7 m (23 ft) SE of the SW corner of the radio house,
7 m (22 ft) SW of the SW corner of the fence around the radio tower, and level
with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: Y 311 1970
DESIGNATION: Y 311
ALIAS: 11.188
MONUMENTATION: Bench Mark disk VM#: 5678
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AD2604
SETTING CLASSIFICATION: Concrete lighthouse base OPUS PID:
LATITUDE: 26° 15.5' N ( 26.25830) LONGITUDE: 80° 4.8' W ( -80.08000)
The bench mark is a disk set in the top of the east side of the concrete
lighthouse base at the U.S. Coast Guard station, 51 m (168 ft) south of bench
mark Z 311 1970, 4.45 m (14.6 ft) west of the SE leg of the lighthouse, 3 m (10
ft) south of the SE corner of the lighthouse steps, and level with the ground.
Note: The bench mark is covered by a thin layer of tar and gravel.
BENCH MARK STAMPING: 16.770
DESIGNATION: 16.770 FLHD
ALIAS: 16.726
MONUMENTATION: Survey disk VM#: 5680
AGENCY: Florida State Road Department (FLSRD) IDB PID#: AD2608
SETTING CLASSIFICATION: Concrete bridge sidewalk OPUS PID:
LATITUDE: 26° 15.7' N ( 26.26170) LONGITUDE: 80° 5.0' W ( -80.08330)
The bench mark is a disk set on the top of the sidewalk of the State Highway A1A
bridge over Hillsboro Inlet, 60 m (198 ft) NE of the SW end of the bridge, 4.57
m (15.0 ft) SE of the centerline of State Highway A1A, 0.30 m (1.0 ft) SE of the
NW edge of the sidewalk, and 0.30 m (1.0 ft) above the bridge floor.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 18.090
DESIGNATION: 18.090 FLHD
ALIAS: 18.045
MONUMENTATION: Survey disk VM#: 5681
AGENCY: Florida State Road Department (FLSRD) IDB PID#: AD2607
SETTING CLASSIFICATION: Concrete bridge curb OPUS PID:
LATITUDE: 26° 15.7' N ( 26.26170) LONGITUDE: 80° 5.0' W ( -80.08330)
The bench mark is a disk set on the top of the NW curb of the State Highway A1A
bridge over Hillsboro Inlet, 4.75 m (15.6 ft) NW of the centerline of State
Highway A1A, 2.10 m (6.9 ft) SW of the NE end of the bannister, and 0.3 m (1 ft)
above road level. NOTE: Mark not found in 2001 & 2002 by US Power Squadron.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
T I D A L D A T U M S
Tidal datums at HILLSBORO INLET OCEAN based on:
LENGTH OF SERIES: 8 MONTHS
TIME PERIOD: December 1970 - July 1971
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8723170 MIAMI BEACH (CITY PIER)
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.859
MEAN HIGH WATER MHW = 0.819
North American Vertical Datum NAVD88 = 0.743
MEAN TIDE LEVEL MTL = 0.435
MEAN SEA LEVEL MSL = 0.434
MEAN LOW WATER MLW = 0.052
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
Z 311 1970 4.118 3.299
Y 311 1970 3.676 2.857
16.770 5.359 4.540
18.090 5.758 4.939
Foot Notes:
MSL is inferred.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8722862 PUBLICATION DATE: 12/12/2003
Name: HILLSBORO INLET OCEAN
FL
NOAA Chart: 11466 Latitude: 26° 15.4' N ( 26.25670)
USGS Quad: BOCA RATON Longitude: 80° 4.8' W ( -80.08000)
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.