U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
To reach the tidal bench marks from Ace Hardware Store on Cleveland Street and
U.S. Highway 1 in Sebastian, proceed 1 block east on Cleveland Street, then
south on Indian River Drive to the Sebastian Yacht Club. The bench marks are
located in the vicinity of the hardware store and the yacht club. The tide gage
and staff were located on the yacht club dock.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1969
DESIGNATION: 872 2029 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 5400
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AF3497
SETTING CLASSIFICATION: Seawall OPUS PID#: AF3497
LATITUDE: 27° 48.7' N ( 27.81083) LONGITUDE: 80° 27.9' W ( -80.46444)
The primary bench mark is a disk set in the NE corner of the south wingwall of
the boat launch ramp of the Sebastian Yacht Club, 29 m (96 ft) SSE of the SE
corner of the yacht club building, 8.66 m (28.4 ft) east of the west end of the
bulkhead, 7.19 m (23.6 ft) north of the south corner, 0.30 m (1.0 ft) south of
the north face, and 0.21 m (0.7 ft) west of the east face of the south wingwall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 2 1969
DESIGNATION: 872 2029 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 5401
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AF3498
SETTING CLASSIFICATION: Retaining wall OPUS PID:
LATITUDE: 27° 48.7' N ( 27.81083) LONGITUDE: 80° 27.9' W ( -80.46528)
The bench mark is a disk set flush in the concrete retaining wall at the NW
corner of the property, 12.50 m (41.0 ft) east of the centerline of Indian River
Drive, 3.93 m (12.9 ft) east of the east edge of a 2.44 m (8.0 ft) concrete
sidewalk, 2.10 m (6.9 ft) north of a 2-inch emergency shut off water valve
projecting 0.79 m (2.6 ft) above the level of the ground, 1.74 m (5.7 ft) SE of
an electric meter box, 1.65 m (5.4 ft) ENE of a wooden light pole, and 0.30 m
(1.0 ft) east of the west end of the concrete seawall.
BENCH MARK STAMPING: NO 3 1969
DESIGNATION: 872 2029 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 5402
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AF3502
SETTING CLASSIFICATION: Sidewalk OPUS PID:
LATITUDE: 27° 48.6' N ( 27.81028) LONGITUDE: 80° 28.0' W ( -80.46611)
The bench mark is a disk set flush in the top of the concrete sidewalk near the
NW corner of the Ace Hardware building and 0.91 m (3.0 ft) above the level of
Cleveland Street, 15.24 m (50.0 ft) south of the south curb of Cleveland Street,
1.77 m (5.8 ft) west of the NW corner of the Ace Hardware building, 0.85 m (2.8
ft) north of a flagpole, and 0.40 m (1.3 ft) NE of the SW corner of the concrete
sidewalk.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 5 1969
DESIGNATION: 872 2029 TIDAL 5
MONUMENTATION: Tidal Station disk VM#: 5404
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AF3495
SETTING CLASSIFICATION: Seawall OPUS PID#: AF3495
LATITUDE: 27° 48.6' N ( 27.81056) LONGITUDE: 80° 27.9' W ( -80.46500)
The bench mark is a disk set flush in the top of the west end of the concrete
seawall 12.19 m (40.0 ft) east of the centerline of Indian River Drive, 7.50 m
(24.6 ft) north of a wooden power pole with transformer and four guy wires, 3.93
m (12.9 ft) NE of the east edge of a 1.83 m (6.0 ft) concrete sidewalk, 2.68 m
(8.8 ft) west of a wooden power pole with three guy wires, 1.31 m (4.3 ft) north
of the NE corner of a square concrete base of a sewer cap, and 0.30 m (1.0 ft)
east of the west end of the concrete seawall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: P 401 1991
DESIGNATION: P 401
MONUMENTATION: Flange-encased Rod VM#: 19491
AGENCY: National Geodetic Survey (NGS) IDB PID#: AF7497
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 27° 47.9' N ( 27.79806) LONGITUDE: 80° 27.6' W ( -80.46028)
The bench mark is a disk 41.09 m (134.8 ft) east of the centerline of the
northbound lanes of the highway, 8.81 m (28.9 ft) west of the centerline of
Indian River Drive south, 0.61 m (2.0 ft) south of a utility pole, 0.30 m (1.0
ft) east of a witness post, and 0.30 m (1.0 ft) below the level of the highway.
Note: Access to the datum point is through a 5-inch logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
T I D A L D A T U M S
Tidal datums at SEBASTIAN, INDIAN RIVER based on:
LENGTH OF SERIES: 2 years
TIME PERIOD: 8/1/69-7/31/70 & 9/1/72-8/31/73
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:
HIGHEST OBSERVED WATER LEVEL (10/19/1973) = 0.701
North American Vertical Datum NAVD88 = 0.342
MEAN HIGHER HIGH WATER MHHW = 0.136
MEAN HIGH WATER MHW = 0.114
MEAN SEA LEVEL MSL = 0.068
MEAN TIDE LEVEL MTL = 0.068
MEAN LOW WATER MLW = 0.021
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (03/05/1970) = -0.384
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 1 1969 1.487 1.373
NO 2 1969 1.501 1.387
NO 3 1969 3.009 2.895
NO 5 1969 1.463 1.349
P 401 1991 2.024 1.910
Foot Notes:
Bench mark P 401 1991 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: 8722029 PUBLICATION DATE: 02/14/2011
Name: SEBASTIAN, INDIAN RIVER
FL
NOAA Chart: 11476 Latitude: 27° 48.7' N ( 27.81170)
USGS Quad: SEBASTIAN Longitude: 80° 27.8' W ( -80.46330)
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.