U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
To reach the tidal bench marks from eastbound Interstate 95, take the east Main
Street exit, proceed south on east Main Street for 0.1 mile (0.2 km), proceed
left onto Stratford Avenue for 0.1 mile (0.2 km), and right on Pembroke Street
to Pauls Diesel Repair. The bench marks are located within a 1 mile (1.6 km)
radius of the tide station. The tide house is at the end of the pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING:
MONUMENTATION: VM#: 258
AGENCY: PID#: AI1725
SETTING CLASSIFICATION:
BENCH MARK STAMPING: TIDAL 12 ELEV. 15.321 FT
MONUMENTATION: Survey Disk VM#: 248
AGENCY: PID#: LX0856
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is located in the front foundation wall at 445 Stratford Avenue,
128 feet (39.0 m) east of the centerline of Pembroke Street, 34.2 feet (10.4 m)
NW of the centerline of Stratford Avenue, and 1 foot (0.3 m) east of the SW
corner of the building. The bench mark is set vertically 0.5 foot (0.2 m) above
ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: T2 1922 ELEV. 16.772 FT
MONUMENTATION: Survey Disk VM#: 249
AGENCY: PID#: LX0855
SETTING CLASSIFICATION: Granite Foundation
The bench mark is located at the SE corner of the intersection of State Street
and Main Street in the NW corner of the Connecticut National Bank granite
foundation, 41.8 feet (12.7 m) ESE of the centerline of Main Street, 27 feet
(8.2 m) south of the centerline of State Street, and 6.2 feet (1.9 m) east of
the NW corner of the bank building. The bench mark is set 1.6 feet (0.5 m)
above the sidewalk.
BENCH MARK STAMPING: 14 1942
MONUMENTATION: Survey Disk VM#: 250
AGENCY: PID#: LX0852
SETTING CLASSIFICATION: Granite Step
The bench mark is set in the granite step at the United Illuminating Company
main entrance at 1115 Broad Street, 61 feet (19 m) north of the centerline of
Cannon Street, 39.0 feet (11.9 m) north of the SE corner of the United
Illuminating Company building, and 30.2 feet (9.2 m) WSW of the centerline of
Broad Street. The bench mark is 0.5 foot (0.2 m) above the sidewalk.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: A31 1963
MONUMENTATION: Survey Disk VM#: 251
AGENCY: PID#: LX0861
SETTING CLASSIFICATION: Concrete Wall
The bench mark is located at the Stratford Avenue underpass beneath the
Connecticut Turnpike, 87.0 feet (26.6 m) SE of light pole #9058, 37.9 feet (11.6
m) east of the centerline of Stratford Avenue, and 1.0 feet (0.3 m) east of the
west corner of the south abutment of the underpass wall. The bench mark is 2.5
feet (0.8 m) above ground level, and is set vertically in the SE corner of the
east headwall.
BENCH MARK STAMPING: NO 15 1964
MONUMENTATION: Survey Disk VM#: 252
AGENCY: PID#: LX0857
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set flush in the concrete floor located inside the Hitchcocks
Gas Engine Companys machine shop, 46.2 feet (14.1 m) SE of the most NE corner of
Hitchcocks Gas Engine Company, 11 feet (3 m) SE of a stairway leading to the
office, 8.8 feet (2.7 m) SW of the NE corner of the machine shop, and 4.5 feet
(1.4 m) west of the interior face of the east wall of the building.
BENCH MARK STAMPING: NO 16 1973
MONUMENTATION: Survey Disk VM#: 253
AGENCY: PID#: LX2345
SETTING CLASSIFICATION: Concrete Headwall
The bench mark is set in the marine railway concrete headwall, located on the
west side of the Hitchcock Marina building, 22.4 feet (6.8 m) east of the east
door leading to the engine shop, 16.0 feet (4.9 m) east of the east rail of the
railway, and 0.9 foot (0.3 m) north of the south end of the railway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 17 1973
MONUMENTATION: Survey Disk VM#: 254
AGENCY: PID#: LX2344
SETTING CLASSIFICATION: Concrete Footing
The bench mark is set in a concrete footing for a wire fence located on the east
edge of the Hitchcock Gas Engine Company property, 45.7 feet (13.9 m) SE of the
east corner of the two-story brick machine shop, 39.1 feet (11.9 m) south of a
metal gate post in the yard, 23.6 feet (7.2 m) NE of the NE corner of the engine
shop, 18 feet (5 m) south of the south end of an asphalt drive leading to the
marina, and 5 feet (2 m) north of a fire hydrant. The bench mark is 0.7 foot
(0.2 m) above ground level.
BENCH MARK STAMPING: CITY OF BRIDGEPORT
MONUMENTATION: Survey Disk VM#: 255
AGENCY: PID#: LX0859
SETTING CLASSIFICATION: Concrete Sidewalk
The bench mark is set in concrete sidewalk located on the NE corner of the
intersection of Stratford Avenue and Hough Avenue, 26.3 feet (8.0 m) north of
the traffic island on Stratford Avenue, 22.9 feet (7.0 m) east of the centerline
of Hough Avenue, and 7.0 feet (2.1 m) east of the east line of the curb of Hough
and Stratford Avenues, and 2.4 feet (0.7 m) north of the north curb of Hough and
Stratford Avenues.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: CHD D1310 BASELINE
MONUMENTATION: Survey Disk VM#: 256
AGENCY: PID#: LX2343
SETTING CLASSIFICATION: Concrete Sidewalk
The bench mark is set in a concrete sidewalk located directly under the east-
bound lane of Interstate 95 along Stratford Avenue just east of the Pequonnock
River bridge, 26.6 feet (8.1 m) west of light pole #528, 8.3 feet (2.6 m) north
of a chain link fence, and 2.0 feet (0.6 m) south of the curb.
BENCH MARK STAMPING: V2 20.49
MONUMENTATION: Survey Disk VM#: 257
AGENCY: PID#: LX0864
SETTING CLASSIFICATION: Stone Step
The bench mark is set in the south end of the bottom step, located on Hollister
Street at the southernmost entrance to McKinley School, 54.0 feet (16.5 m) east
of the centerline of Hollister Street, 35.2 feet (10.7 m) north of the SW corner
of the brickwork at the basement level, 12 feet (4 m) north of the south end of
the building, and 7.6 feet (2.3 m) south of the north edge of the southerly
entrance way on the west face of the building. The bench mark is 0.3 foot (0.1
m) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
T I D A L D A T U M S
Tidal datums at BRIDGEPORT, BRIDGEPORT HARBOR based on:
LENGTH OF SERIES: 18 YEARS
TIME PERIOD: 1967-1984
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8518750 THE BATTERY, NY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (09/21/1938) = 12.44
MEAN HIGHER HIGH WATER MHHW = 7.33
MEAN HIGH WATER MHW = 6.99
MEAN TIDE LEVEL MTL = 3.62
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 2.92
MEAN LOW WATER MLW = 0.25
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (02/02/1976) = -4.41
* NGVD reference based on adjustment of 1967 and NOS levels of 1967-1984.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
0 0.00 0.00
TIDAL 12 ELEV. 15.321 FT 18.24 11.25
T2 1922 ELEV. 16.772 FT 19.69 12.70
14 1942 21.31 14.32
A31 1963 23.37 16.38
NO 15 1964 13.36 6.37
NO 16 1973 9.37 2.38
NO 17 1973 13.07 6.08
CITY OF BRIDGEPORT 16.08 9.09
CHD D1310 BASELINE 11.54 4.55
V2 20.49 23.34 16.35
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
PUBLICATION DATE: 11/06/1986
Station ID: 8467150 SUPERCEDED DATE: 04/21/2003
Name: BRIDGEPORT, BRIDGEPORT HARBOR
CONNECTICUT
NOAA Chart: 12369 Latitude: 41° 10.4' N
USGS Quad: BRIDGEPORT Longitude: 73° 10.9' W
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 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.