U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
To reach the tidal bench marks from the Bogie Channel Bridge linking Doctors
Point on Big Pine Key to No Name Key, proceed NE by boat for 6.1 km (3.8 statute
mi) to the northern tip of Little Pine Key. The bench marks are located on the
northern tip of the Key. The tide gage and staff were located offshore, NE of
the northern point.
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 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: SPAN 1935
DESIGNATION: SPAN
MONUMENTATION: Triangulation Station disk VM#: 6396
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AA1526
SETTING CLASSIFICATION: Bedrock OPUS PID:
LATITUDE: 24° 45.0' N ( 24.75000) LONGITUDE: 81° 19.7' W ( -81.32830)
The primary bench mark is a disk set flush in bedrock located 220 m (722 ft)
from the extreme northern point of the island, 60 m (197 ft) east of the western
shore with mangroves, 0.40 m (1.3 ft) NW of a witness post, and is level with
the surrounding bedrock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: SPAN NO 1 1935
DESIGNATION: SPAN RM 1
MONUMENTATION: Reference Mark disk VM#: 6397
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Bedrock OPUS PID:
LATITUDE: 24° 45.0' N ( 24.75000) LONGITUDE: 81° 19.7' W ( -81.32830)
The bench mark is a disk set in bedrock, 10.52 m (34.5 ft) NE of bench mark SPAN
1935, 0.37 m (1.2 ft) south of a witness post, and 0.03 m (0.1 ft) above the
surrounding bedrock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: SPAN NO 2 1935
DESIGNATION: SPAN RM 2
MONUMENTATION: Reference Mark disk VM#: 6398
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Bedrock OPUS PID:
LATITUDE: 24° 45.0' N ( 24.75000) LONGITUDE: 81° 19.7' W ( -81.32830)
The bench mark is a disk set in bedrock, 15.39 m (50.5 ft) west of bench mark
SPAN NO 1 1935, 13.62 m (44.7 ft) NW of bench mark SPAN 1935, 0.40 m (1.3 ft) NW
of an old wooden witness post, 0.30 m (1.0 ft) NW of a new witness post, and
0.03 m (0.1 ft) above the surrounding bedrock.
BENCH MARK STAMPING: NO 4 1974
DESIGNATION: 872 4177 TIDAL 4
MONUMENTATION: Tidal Station disk VM#: 6399
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Deep rod OPUS PID:
LATITUDE: 24° 45.0' N ( 24.75000) LONGITUDE: 81° 19.7' W ( -81.32830)
The bench mark is a disk located 19.90 m (65.3 ft) east of bench mark SPAN 1935,
17.74 m (58.2 ft) ESE of bench mark SPAN NO 1 1935, and 0.43 m (1.4 ft) NE of a
witness post. The mark is set 12 cm (0.4 ft) above ground level, crimped to the
top of a rod driven an unspecified depth to refusal, and encased in concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 5 1974
DESIGNATION: 872 4177 TIDAL 5
MONUMENTATION: Tidal Station disk VM#: 6400
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Deep rod OPUS PID:
LATITUDE: 24° 45.0' N ( 24.75000) LONGITUDE: 81° 19.7' W ( -81.32830)
The bench mark is a disk located 29.57 m (97.0 ft) SW of the outer edge of
mangroves, 28.19 m (92.5 ft) ENE of bench mark NO 4 1974, 23.16 m (76.0 ft) SW
of a witness sign nailed to a tree, 3 m (10 ft) south of the inner mangrove
edge, and 0.3 m (1.0 ft) NE of a witness post. The mark is set 15 cm (0.5 ft)
above ground level, crimped to the top of a rod driven an unspecified depth to
refusal, and encased in concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
T I D A L D A T U M S
Tidal datums at LITTLE PINE KEY NORTH based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: August 1974 - August 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 = 0.551
MEAN HIGH WATER MHW = 0.484
MEAN TIDE LEVEL MTL = 0.286
MEAN SEA LEVEL MSL = 0.263
MEAN LOW WATER MLW = 0.088
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
SPAN 1935 0.683 0.199
SPAN NO 1 1935 0.666 0.182
SPAN NO 2 1935 0.700 0.216
NO 4 1974 0.794 0.310
NO 5 1974 0.839 0.355
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8724177 PUBLICATION DATE: 02/26/2004
Name: LITTLE PINE KEY NORTH
FL
NOAA Chart: 11448 Latitude: 24° 45.0' N ( 24.75000)
USGS Quad: BIG PINE KEY Longitude: 81° 19.7' W ( -81.32830)
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.