U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
To reach the tidal bench marks from the intersection of U.S. Highway 1 and State
Road 940, proceed 2.7 km (1.7 mi) NW on State Road 940, then 1.3 km (0.8 mi)
east on Watson Boulevard to the intersection of Watson Boulevard and Avenue B to
the entrance to Halayon Beach Trailer Park. The bench marks are located on the
grounds of the trailer park in the vicinity of the recreation hall. The tide
gage and staff were located on the pier east of the recreation hall.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1974
DESIGNATION: 872 4201TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 6431
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0907
SETTING CLASSIFICATION: Concrete step OPUS PID:
LATITUDE: 24° 41.4' N ( 24.69000) LONGITUDE: 81° 21.4' W ( -81.35670)
The primary bench mark is a disk set in the second step located on the east side
of the trailer park recreation hall, 27 m (90 ft) west of the edge of the water,
5 m (18 ft) north from the SE corner of the building, 1 m (4 ft) east of the
entrance to the recreation hall, and 0.3 m (1 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 2 1974
DESIGNATION: 872 4201TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 6432
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0906
SETTING CLASSIFICATION: Concrete step OPUS PID:
LATITUDE: 24° 41.4' N ( 24.69000) LONGITUDE: 81° 21.4' W ( -81.35670)
The bench mark is a disk set in the second step located on the north side of the
trailer park recreation hall, 11 m (35 ft) south of the centerline of the north
entrance road, 8 m (25 ft) west of the NE corner of the building, 2 m (6 ft)
east of the NW corner of the building, and 0.3 m (1 ft) above ground level.
BENCH MARK STAMPING: NO 3 1974
DESIGNATION: 872 4201 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 6433
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0905
SETTING CLASSIFICATION: Concete pad OPUS PID:
LATITUDE: 24° 41.4' N ( 24.69000) LONGITUDE: 81° 21.4' W ( -81.35670)
The bench mark is a disk set in the top of a concrete trailer pad located on the
seventh trailor pad east of Avenue B, 13 m (42 ft) south of the centerline of
the north entrance road, and 1 m (2 ft) SW of the NE corner of the trailer pad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 4 1974
DESIGNATION: 872 4201 TIDAL 4
MONUMENTATION: Tidal Station disk VM#: 6434
AGENCY: National Ocean Survey (NOS) IDB PID#: AA0904
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 24° 41.4' N ( 24.69000) LONGITUDE: 81° 21.4' W ( -81.35670)
The bench mark is a disk set in the top of a concrete seawall located at the
private home at the NW corner of the intersection of Watson Boulevard and Avenue
B, 18 m (60 ft) north of the centerline of Watson Boulevard, and 0.30 m (1.0 ft)
west of the SE cornr of the canal sea wall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: C 273 1966
DESIGNATION: C 273
MONUMENTATION: Bench Mark disk VM#: 6435
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AA0242
SETTING CLASSIFICATION: Concrete wing wall OPUS PID:
LATITUDE: 24° 41.5' N ( 24.69170) LONGITUDE: 81° 21.5' W ( -81.35830)
The bench mark is a disk set in top of the west concrete wingwall of a 7 m (24
ft) bridge over a canal located north of the intersection of Watson Boulevard
and Avenue B, and 5 m (17 ft) west of the centerline of Avenue B.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
T I D A L D A T U M S
Tidal datums at DOCTORS ARM based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: October 1974 - October 1974
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8724211 BIG PINE KEY VIADUCT
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
North American Vertical Datum NAVD88 = 0.385
MEAN HIGHER HIGH WATER MHHW = 0.364
MEAN HIGH WATER MHW = 0.286
MEAN SEA LEVEL MSL = 0.184
MEAN TIDE LEVEL MTL = 0.167
MEAN LOW WATER MLW = 0.048
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 1 1974 0.876 0.590
NO 2 1974 1.061 0.775
NO 3 1974 1.071 0.785
NO 4 1974 0.963 0.677
C 273 1966 2.664 2.378
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8724201 PUBLICATION DATE: 05/12/2004
Name: DOCTORS ARM
FL
NOAA Chart: 11445 Latitude: 24° 41.4' N ( 24.69000)
USGS Quad: PIG PINE KEY Longitude: 81° 21.4' W ( -81.35670)
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.