U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
To reach the tidal bench marks from the post office in Sugarloaf Key, proceed
3.9 km (2.4 mi) NE on U.S. Highway 1 to Crane Boulevard, then turn left and
proceed north on Hawkwsbill Road for 0.4 km (0.2 mi) to 19 Hawkesbill Road. The
bench marks are located in the area along the dirt road (Hawkesbill Road). The
tide gage and staff were located on the U.S. Government Wildlife Refuge Pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 3 1974
DESIGNATION: 872 4347 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 6991
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0763
SETTING CLASSIFICATION: Copper-coated steel rod OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The primary bench mark is a disk located 68 m (224 ft) south of the north end of
a canal, 39.6 m (130.0 ft) south of a chain link fence for the last house at the
end of the road, 34 m (110 ft) NNE of the NW corner of next to the last house
along the road, and 3.20 m (10.5 ft) west of the west side of the canal. The
bench mark is crimped to a copper-coated steel rod driven to refusal, encased in
a PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 1 1974
DESIGNATION: 872 4347 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 6989
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-coated steel rod OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The bench mark is a disk located 41.45 m (136.0 ft) north of bench mark NO 3
1974, 41.30 m (135.5 ft) SE of bench mark NO 2 1974, 26.82 m (88.0 ft) south of
the point of land at the end of the canal, 3.20 m (10.5 ft) west of the west
side of the canal, and 1.34 m (4.4 ft) north of a small palm tree. The bench
mark is set 8 cm (0.2 ft) above the ground, crimped to a copper-coated steel rod
driven to refusal, encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: NO 2 1974
DESIGNATION: 872 4347 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 6990
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-coated steel rod OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The bench mark is a disk located 41.30 m (135.5 ft) NW of bench mark NO 1 1974,
23.47 m (77.0 ft) NE of the center of a water valve cover and 8.38 m (27.5 ft)
to the shoreline. The bench mark is set 8 cm (0.2 ft) above the ground, crimped
to a copper-coated steel rod driven to refusal, and encased in a PVC pipe and
concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 4 1974
DESIGNATION: 872 4347 TIDAL 4
MONUMENTATION: Tidal Station disk VM#: 6992
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-coated steel rod OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The bench mark is a disk located 0.5 km (0.3 mi) north along a dirt road from
Crane Boulevard on the east side of the Key, 13.26 m (43.5 ft) west of the
centerline of the dirt road, and 6.55 m (21.5 ft) east of the centerline of the
paved road. The bench mark is set 8 cm (0.2 ft) above ground level, crimped to
a copper-coated steel rod driven to refusal, encased in a PVC pipe and concrete
kickblock.
BENCH MARK STAMPING: NO 5 1974
DESIGNATION: 872 4347 TIDAL 5
MONUMENTATION: Tidal Station disk VM#: 6993
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0762
SETTING CLASSIFICATION: Copper-coated steel rod OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The bench mark is a disk located 8.69 m (28.5 ft) west of the west side of the
canal, 7.99 m (26.2 ft) SSW of the NE corner of the house, 4.48 m (14.7 ft) NW
of the SE corner of the house (underneath the house which is on stilts). The
bench mark is crimped to a copper-coated steel rod driven to refusal, encased in
a PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4347 F 1982
DESIGNATION: 872 4347 F TIDAL
MONUMENTATION: Tidal Station disk VM#: 6994
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0761
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 24° 40.3' N ( 24.67170) LONGITUDE: 81° 32.0' W ( -81.53330)
The bench mark is a disk set in the concrete seawall behind the house on lot #9
on Hawkes Bill Lane, 20.57 m (67.5 ft) south of the north end of the seawall,
10.52 m (34.5 ft) SE of the SE corner of the house, and 0.30 m (1.0 ft) north of
the south end of the seawall.
BENCH MARK STAMPING: 4347 G 1982
DESIGNATION: 872 4347 G TIDAL
MONUMENTATION: Tidal Station disk VM#: 6995
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0760
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 24° 40.2' N ( 24.67000) LONGITUDE: 81° 32.1' W ( -81.53500)
The bench mark is a disk set in a concrete sea wall located near 6 Hawkins Bill
Lane, 13.75 m (45.1 ft) north of the south end of the sea wall, 7.6 m (24.8 ft)
ESE of the NE corner of the house, and 6.98 m (22.9 ft) south of the north end
of the sea wall behind the second house on the right side of Hawkes Bill Lane.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4347 H 1982
DESIGNATION: 872 4347 H TIDAL
MONUMENTATION: Tidal Station disk VM#: 6996
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0759
SETTING CLASSIFICATION: Concrete base for flagpole OPUS PID:
LATITUDE: 24° 39.7' N ( 24.66170) LONGITUDE: 81° 31.8' W ( -81.53000)
The bench mark is a disk set in the concrete base for a flagpole at the
Sugarloaf Elementary School, 14.17 m (46.5 ft) NNE of the NW corner of the
Administration building, 12.98 m (42.6 ft) SW of the NW corner of the cafeteria,
11.73 m (38.5 ft) east of the centerline of the semi-circular drive, 0.34 m (1.1
ft) west of the flagpole, and 0.03 m (0.1 ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
T I D A L D A T U M S
Tidal datums at SUGARLOAF KEY EAST SIDE based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: May 1974 - May 1974
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8724580 KEY WEST
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.554
MEAN HIGH WATER MHW = 0.471
MEAN TIDE LEVEL MTL = 0.261
MEAN SEA LEVEL MSL = 0.257
MEAN LOW WATER MLW = 0.051
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 3 1974 1.065 0.594
NO 1 1974 1.186 0.715
NO 2 1974 1.053 0.582
NO 4 1974 1.608 1.137
NO 5 1974 1.539 1.068
4347 F 1982 1.102 0.631
4347 G 1982 0.981 0.510
4347 H 1982 2.511 2.040
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8724347 PUBLICATION DATE: 05/28/2004
Name: SUGARLOAF KEY EAST SIDE
FL
NOAA Chart: 11434 Latitude: 24° 40.3' N ( 24.67170)
USGS Quad: SUGARLOAF KEY Longitude: 81° 32.0' W ( -81.53330)
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.