U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
To reach the tidal bench marks from Indian River Inlet Bridge, proceed north on
State Highway 1 to the first road (unmarked) to the west, continue on it for
approximately 0.8 km (0.5 mi) to Indian River Inlet Coast Guard Base. The bench
marks are located on the Coast Guard Base and adjacent campground parking lot.
The tide gage and staff were located in the SE corner of the Coast Guard Base.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8690 M 1980
DESIGNATION: 855 8690 M
MONUMENTATION: Tidal Station disk VM#: 3012
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBDF18
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The primary bench mark is a disk located in the Coast Guard Base at the SE
corner of the tennis courts, 17.77 m (58.3 ft) east of the orange and white FM
antenna, 12.53 m (41.1 ft) NE of the NE corner of the water pump house, 0.52 m
(1.7 ft) west of the chain fence around the base, and 0.3 m (1.0 ft) south of
the south face of the tennis courts. The bench mark is set level with the
ground, crimped to a stainless steel rod driven 11 m (36 ft) to refusal, and
encased in a 4-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: INDIAN 2 1962
DESIGNATION: 855 8690 INDIAN 2
MONUMENTATION: Tidal Station disk VM#: 3005
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Concrete curb OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set flush in the NW section of the concrete curb around
a 1.52 m (5.0 ft) diameter sewer manhole in the campground parking area, 73 m
(241 ft) north of the seawall, 37.70 m (123.7 ft) NW of the NW steel leg of a
radio transmission tower, 25.45 m (83.5 ft) west of the west face of a telephone
booth, and level with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: R 27 1962
DESIGNATION: R 27
MONUMENTATION: Tidal Station disk VM#: 3006
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: HU0108
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 38° 36.7' N ( 38.61170) LONGITUDE: 75° 3.8' W ( -75.06330)
The bench mark is a disk located in the campground parking lot, in the NE corner
of the NE concrete foundation of the electric transmission tower on the north
side of Indian River Inlet, and about 1 m (3 ft) above ground level.
BENCH MARK STAMPING: NO 3 1972
DESIGNATION: 855 8690 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 3007
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set flush in the SE corner of the concrete foundation
supporting the oil storage tank on the Coast Guard Base, 2.01 m (6.6 ft) NE of a
concrete splash wall, 0.98 m (3.2 ft) NW of a concrete splash wall, and 0.46 m
(1.5 ft) SE of the SW leg of the fuel tank.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8690 G 1977
DESIGNATION: 855 8690 G
MONUMENTATION: Tidal Station disk VM#: 3008
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set in a concrete monument at the entrance to the Coast
Guard Base, 8.05 m (26.4 ft) west of the centerline of the asphalt road leading
into the base, 2.19 m (7.2 ft) NW of the westerly of the two white buoys marking
the entrance, 0.43 m (1.4 ft) south of telephone pole #4, and level with the
ground.
BENCH MARK STAMPING: 8690 H 1977
DESIGNATION: 855 8690 H
MONUMENTATION: Tidal Station disk VM#: 3009
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set in a concrete monument at the north edge of the
campground parking lot, 10.67 m (35.0 ft) north of the centerline of the dirt
road, 8.84 m (29.0 ft) west of a sign, 8.69 m (28.5 ft) south of the centerline
of the asphalt road, 1 m (3 ft) south of telephone pole #6, and level with the
ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8690 J 1977
DESIGNATION: 855 8690 J
MONUMENTATION: Tidal Station disk VM#: 3010
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set in a concrete monument in the NE corner of the
campground parking lot, 10.52 m (34.5 ft) south of the centerline of the asphalt
road, 10.00 m (32.8 ft) NE of the NW corner of the park service office, 6.00 m
(19.7 ft) north of the NE corner of the park service office, 3 m (10 ft) west of
the west edge of the parking lot, and level with the ground.
BENCH MARK STAMPING: 8690 L 1979
DESIGNATION: 855 8690 L
MONUMENTATION: Tidal Station disk VM#: 3011
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete base OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk set flush in the NE corner of the concrete in the base
of a radio antenna at the Coast Guard Base, 16.40 m (53.8 ft) west of a fire
main, 13.62 m (44.7 ft) SE of the NW corner of the chain link fence, and 3.87 m
(12.7 ft) north of the NW corner of the Coast Guard Administration building.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8690 N 1980
DESIGNATION: 855 8690 N
MONUMENTATION: Tidal Station disk VM#: 3013
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 38° 36.6' N ( 38.61000) LONGITUDE: 75° 4.2' W ( -75.07000)
The bench mark is a disk located in the Coast Guard Base at the NW corner of the
tennis courts, 24 m (79 ft) east of the centerline of the entrance road to the
base, 10.55 m (34.6 ft) NE of the NE corner of the garage, 0.52 m (1.7 ft) west
of the west face of the tennis courts, and 0.3 m (1 ft) south of the chain link
fence around the base. The bench mark is set level with the ground, crimped to
a stainless steel rod driven 14.3 m (47 ft) to refusal, and encased in a 4-inch
PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
T I D A L D A T U M S
Tidal datums at INDIAN RIVER INLET based on:
LENGTH OF SERIES: 9 Years
TIME PERIOD: August 1977 - July 1986
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8557380 LEWES, FT. MILES
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (03/29/1984) = 1.808
MEAN HIGHER HIGH WATER MHHW = 0.895
MEAN HIGH WATER MHW = 0.813
MEAN SEA LEVEL MSL = 0.452
MEAN TIDE LEVEL MTL = 0.430
MEAN LOW WATER MLW = 0.047
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/10/1978) = -1.283
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8690 M 1980 2.567 1.754
INDIAN 2 1962 2.034 1.221
R 27 1962 3.051 2.238
NO 3 1972 2.271 1.458
8690 G 1977 2.535 1.722
8690 H 1977 2.459 1.646
8690 J 1977 1.811 0.998
8690 L 1979 2.435 1.622
8690 N 1980 2.401 1.588
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 8558690 PUBLICATION DATE: 04/21/2003
Name: INDIAN RIVER INLET
DE
NOAA Chart: 12216 Latitude: 38° 36.6' N ( 38.61000)
USGS Quad: BETHANY BEACH Longitude: 75° 4.2' W ( -75.07000)
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.