U.S. DEPARTMENT OF COMMERCE
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Datums Page Page 1 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
To reach the tidal bench marks from the intersection of Commerce Street and U.S.
Highway 1 (West Main Street) in Clinton, proceed south on Commerce Street for
1.0 km (0.6 mi) to its end, then back north on Grove Street one block, then west
on Riverside Drive for 0.3 km (0.2 mi) to the Aqua Restaurant. The bench marks
are along Riverside Drive and Commerce Street, as far north as the Post Office
on West Main Street. The tide gauge was located on the fuel pier at the Cedar
Island Marina next to the restaurant.
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: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 2 1917
DESIGNATION: TIDAL 2 STA 18
MONUMENTATION: Tidal Station disk VM#: 16731
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: LX0470
SETTING CLASSIFICATION: Rock OPUS PID:
LATITUDE: 41° 16.2' N ( 41.27000) LONGITUDE: 72° 31.7' W ( -72.52830)
The primary bench mark is a disk set in the top of a 0.8 m (2.6 ft) x 0.5 m (1.6
ft) flat rock, about 114 m (374 ft) north of the south end of Commerce Street,
in the front yard of a yellow vinyl sided two story house at 130 Commerce
Street, 31 m (102 ft) east of the centerline of Commerce Street, 12 m (39 ft) SE
of the SE corner of a grey 5-car metal garage, 11 m (36 ft) SW of the SW corner
of the house, and 2.59 m (8.5 ft) NE of the centerline of a driveway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: X 36 1965
DESIGNATION: X 36
MONUMENTATION: Bench Mark disk VM#: 16732
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: LX0469
SETTING CLASSIFICATION: Building OPUS PID:
LATITUDE: 41° 16.7' N ( 41.27830) LONGITUDE: 72° 31.6' W ( -72.52670)
The bench mark is a disk set vertically in the north face and the NW corner of
the Post Office building, at the intersection of U.S. Highway 1 (West Main
Street) and Commerce Street, 25 m (82 ft) west of the west curb of Commerce
Street, 7 m (23 ft) south of the south curb of the highway, 0.85 m (2.8 ft) east
of the NW corner of the building, and level with an access ramp. Note: the disk
is halfway covered by the ramp; a tape or scale is needed to level to the disk.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: X 36 RESET 1990
DESIGNATION: X 36 RESET
MONUMENTATION: Vertical Control disk VM#: 16733
AGENCY: National Geodetic Survey (NGS) IDB PID#:
SETTING CLASSIFICATION: Access ramp OPUS PID:
LATITUDE: 41° 16.7' N ( 41.27830) LONGITUDE: 72° 31.6' W ( -72.52670)
The bench mark is a disk set in the access ramp at the NW corner of the Post
Office and next to bench mark X 36 (set vertically in the north wall and
partially covered by the ramp), at the intersection of U.S. Highway 1 (West Main
Street) and Commerce Street, 1.50 m (4.9 ft) SSW of the north edge of the ramp,
0.49 m (1.6 ft) east of the NW corner of the building, and 0.42 m (1.4 ft) NW of
bench mark X 36 1965.
BENCH MARK STAMPING: 3701 A 2002
DESIGNATION: 846 3701 A
MONUMENTATION: Tidal Station disk VM#: 16734
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID#: BBDD46
LATITUDE: 41° 16.1' N ( 41.26830) LONGITUDE: 72° 31.9' W ( -72.53170)
The bench mark is a disk set in the southerly of two large concrete pads
covering fuel tanks at the Aqua Restaurant, just east of the Cedar Island
Marina, 19.03 m (62.4 ft) north of the edge of the bulkhead, 14.17 m (46.5 ft)
SE of the NE corner of the restaurant, 3.46 m (11.4 ft) west of the SE corner of
the pad, and 0.26 m (0.8 ft) north of the south edge of the pad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 3701 B 2002
DESIGNATION: 846 3701 B
MONUMENTATION: Tidal Station disk VM#: 16735
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Sign footer OPUS PID:
LATITUDE: 41° 16.2' N ( 41.27000) LONGITUDE: 72° 31.9' W ( -72.53170)
The bench mark is a disk set in the SW corner of the south footer for the large
wooden Cedar Island Marina sign, 19.20 m (63.0 ft) ESE of the NE corner of the
marina building, 11.63 m (38.2 ft) south of the centerline of Riverside Drive,
and 7.00 m (23.0 ft) WNW of the centerline of the entrance drive of the marina.
BENCH MARK STAMPING: 1 1987
DESIGNATION: 846 3701 TOWN OF CLINTON
MONUMENTATION: Survey disk VM#: 16736
AGENCY: Town of Clinton IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 41° 16.2' N ( 41.27000) LONGITUDE: 72° 31.7' W ( -72.52830)
The bench mark is a disk set in a concrete monument located at the south end of
Commerce Street, 6.85 m (22.5 ft) ENE of the centerline of Grove Street, 6.10 m
(20.0 ft) WNW of the centerline of Commerce Street, 2.40 m (7.9 ft) south of a
tall storm evacuation sign, and 0.25 m (0.8 ft) south of a steel witness post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
T I D A L D A T U M S
Tidal datums at CLINTON, CLINTON HARBOR based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: July 2002 - August 2002
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8467150 BRIDGEPORT, BRIDGEPORT HARBOR
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.552
MEAN HIGH WATER MHW = 1.460
North American Vertical Datum NAVD88 = 0.854
MEAN TIDE LEVEL MTL = 0.766
MEAN SEA LEVEL MSL = 0.751
MEAN LOW WATER MLW = 0.072
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 2 1917 2.303 0.843
X 36 1965 8.527 7.067
X 36 RESET 1990 8.531 7.071
3701 A 2002 2.896 1.436
3701 B 2002 3.211 1.751
1 1987 1.987 0.527
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8463701 PUBLICATION DATE: 05/15/2003
Name: CLINTON, CLINTON HARBOR
CT
NOAA Chart: 12374 Latitude: 41° 16.1' N ( 41.26830)
USGS Quad: CLINTON Longitude: 72° 31.9' W ( -72.53170)
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.