U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
To reach the tidal bench marks at the north end of Charlotte Harbor from Port
Charlotte Beach, proceed by boat WNW (280 degrees) for 4.8 km (3.0 mi) to the
east end of Hog Island at Locust Point. The bench marks are on Locust Point.
The tide gage and staff were located offshore of a point of land surrounding a
small bay.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5745 A 1977
DESIGNATION: 872 5745 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 7394
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The primary bench mark is a disk located 16.46 m (54.0 ft) west of bench mark
5745 B 1977, 6.71 m (22.0 ft) east of the west end of the grassy point of land
on the north side of the small bay, 3 m (10 ft) south of the shoreline, and 0.46
m (1.5 ft) north of a witness post. The bench mark is 3 cm (0.1 ft) below
ground level, crimped to the top of a copper-clad steel rod driven 12.2 m (40
ft), and encased in a concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5745 B 1977
DESIGNATION: 872 5745 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 7395
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The bench mark is a disk set in the top of a concrete monument, 13.72 m (45.0
ft) west of bench mark 5745 C 1977, 4 m (12 ft) south of the shoreline, 0.61 m
(2.0 ft) south of an old witness post, 0.37 m (1.2 ft) north of a new witness
post, and 0.06 m (0.2 ft) below ground level.
BENCH MARK STAMPING: 5745 C 1977
DESIGNATION: 872 5745 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 7396
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The bench mark is a disk located east of the west end of the grassy point of
land on the north side of the small bay, 1 m (4 ft) south of the shoreline, and
0.27 m (0.9 ft) north of a witness post. The bench mark is 0.27 m (0.9 ft)
above ground level, crimped to the top of a copper-clad steel rod driven 9.8 m
(32 ft), and encased in a concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5745 E 1977
DESIGNATION: 872 5745 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 7397
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The bench mark is a disk located east of the west end of the grassy point of
land on the north side of the small bay, 24.38 m (80.0 ft) east of bench mark
5745 C 1977, 2.74 m (9.0 ft) south of the shoreline, and 0.34 m (1.1 ft) north
of a witness post. The bench mark is 0.21 m (0.7 ft) above ground level,
crimped to the top of a copper-clad steel rod driven 9.8 m (32 ft), and encased
in a concrete kickblock.
BENCH MARK STAMPING: 5745 F 1977
DESIGNATION: 872 5745 F TIDAL
MONUMENTATION: Tidal Station disk VM#: 7398
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The bench mark is a disk located east of the west end of the grassy point of
land on the north side of the small bay, 68.58 m (225.0 ft) west of Locust
Point, 23 m (75 ft) east of bench mark 5745 E 1977, and 0.30 m (1.0 ft) north of
a witness post. The bench mark is 0.30 m (1.0 ft) above ground level, crimped
to the top of a copper-clad steel rod driven 9.8 m (32.0 ft), and encased in a
concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5745 G 1981
DESIGNATION: 872 5745 G TIDAL
MONUMENTATION: Tidal Station disk VM#: 7399
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 26° 55.8' N ( 26.93000) LONGITUDE: 82° 8.2' W ( -82.13670)
The bench mark is a disk set in the top of a concrete monument located east of
the west end of the grassy point of land, 16.46 m (54.0 ft) east of bench mark
5745 A 1977, 13.72 m (45.0 ft) west of bench mark 5745 C 1977, 3.66 m (12.0 ft)
south of the shoreline, and 0.30 m (1.0 ft) west of a witness post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
T I D A L D A T U M S
Tidal datums at LOCUST POINT, HOG ISLAND based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: April 1978 - May 1978
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8725110 NAPLES, GULF OF MEXICO
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.594
MEAN HIGH WATER MHW = 0.498
MEAN TIDE LEVEL MTL = 0.313
MEAN SEA LEVEL MSL = 0.307
MEAN LOW WATER MLW = 0.127
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
5745 A 1977 0.857 0.359
5745 B 1977 0.995 0.497
5745 C 1977 0.942 0.444
5745 E 1977 0.882 0.384
5745 F 1977 0.849 0.351
5745 G 1981 0.832 0.334
Foot Notes:
Bench mark 5745 G 1981 is based on one differential leveling connection and does
not meet the quality control standards of the NOS. Therefore, caution should be
used when deriving elevations for this mark.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8725745 PUBLICATION DATE: 02/05/2004
Name: LOCUST POINT, HOG ISLAND
FL
NOAA Chart: 11426 Latitude: 26° 55.8' N ( 26.93000)
USGS Quad: EL JOBEAN Longitude: 82° 8.2' W ( -82.13670)
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.