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Bench Mark Sheet for 8464336, MIDDLETOWN, CONNECTICUT RIVER CT

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


To reach the tidal bench marks from the intersection of Main and Union Streets
in Middletown, proceed east on Union Street beneath the State Highway 9
over-pass to Harbor Drive, then north on Harbor Drive for 0.2 km (0.1 mi) to
Harbour Park Restaurant.  The bench marks are NW of Harbour Park Restaurant. 
The tide gage and staff were on the wharf behind the restaurant.


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  4336 E 1987
                         DESIGNATION:          846 4336 E

MONUMENTATION:           Tidal Station disk                    VM#:         2265
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Retaining wall                        OPUS PID#: BBDC62
LATITUDE:   41° 33.6' N (  41.56000)          LONGITUDE:  72° 38.7' W ( -72.64500)


The primary bench mark is a disk set flush in the top of the south end of a
retaining wall on Harbor Drive, 59 m (192 ft) WNW of the Harbour Park Restaurant
entrance, 57.61 m (189.0 ft) west of a handrail along the river, 17.40 m (57.1
ft) ENE of the east guardrail on State Highway 9, and 1.40 m (4.6 ft) above
ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  92 W 1923 54
                         DESIGNATION:          92 W

MONUMENTATION:           Survey disk                           VM#:         2262
AGENCY:                  US Geological Survey (USGS)           IDB PID#:  LX0580
SETTING CLASSIFICATION:  Concrete steps                        OPUS PID:        
LATITUDE:   41° 34.0' N (  41.56670)          LONGITUDE:  72° 39.2' W ( -72.65330)


The bench mark is a disk set flush in the first step of the west entrance on the
south side of St Johns Catholic Church at Main Street and Hartford Avenue, 31.39
m (103.0 ft) west of the centerline of St Johns street, 16.46 m (54.0 ft) east
of the entrance to St Johns School, 8.17 m (26.8 ft) north of the north curb of
Hartford Avenue, and 0.12 m (0.4 ft) above the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  MIDDLETOWN 1935
                         DESIGNATION:          MIDDLETOWN

MONUMENTATION:           Bench Mark disk                       VM#:         2263
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LX0583
SETTING CLASSIFICATION:  Concrete steps                        OPUS PID:        
LATITUDE:   41° 33.6' N (  41.56000)          LONGITUDE:  72° 39.0' W ( -72.65000)


The bench mark is a disk set flush on the first step of the Connecticut Bank &
Trust near the intersection of Main and Court Streets, 24.26 m (79.6 ft) south
of the SE corner of the post office, 12.68 m (41.6 ft) NW of a yellow and green
fire hydrant, 7.10 m (23.3 ft) west of the west curb of Main Street, and 0.20 m
(0.65 ft) above the sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  Y 14 1935
                         DESIGNATION:          Y 14

MONUMENTATION:           Bench Mark disk                       VM#:         2264
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LX0579
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   41° 34.0' N (  41.56670)          LONGITUDE:  72° 39.0' W ( -72.65000)


The bench mark is a disk set in the top of the NW corner of the New York, New
Haven, and Hartford Railroad bridge abutment on the west side of the river,
18.99 m (62.3 ft) east of the east rail of the north/south railroad tracks, 9.78
m (32.1 ft) NE of the NE corner of a red brick building, 2.13 m (7.0 ft) north
of the north rail of the east/west tracks, and 0.76 m (2.5 ft) below track
level.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          846 4336 NO STAMPING 1

MONUMENTATION:           Survey disk                           VM#:         2266
AGENCY:                  City of Middletown                    IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   41° 33.6' N (  41.56000)          LONGITUDE:  72° 38.7' W ( -72.64500)


The bench mark is a disk set in a concrete monument at the NW corner of Court
Street and Dekoven Drive, near the SE corner of Middletown Municipal Building,
44.78 m (146.9 ft) south of a flagpole, 14.30 m (46.9 ft) north of the
centerline of Court Street, 3.84 m (12.6 ft) east of the SE corner of the stone
landing of the Middletown Municipal Building steps, and 0.37 m (1.2 ft) above
ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


                            T I D A L   D A T U M S 


Tidal datums at MIDDLETOWN, CONNECTICUT RIVER based on:

     LENGTH OF SERIES:      16 MONTHS
     TIME PERIOD:           June 1987 - September 1988
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8461490 NEW LONDON, THAMES RIVER


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     HIGHEST OBSERVED WATER LEVEL (05/02/1988)         =
     MEAN HIGHER HIGH WATER                     MHHW   =  0.770
     MEAN HIGH WATER                            MHW    =  0.695
     MEAN SEA LEVEL                             MSL    =  0.374
     MEAN TIDE LEVEL                            MTL    =  0.364
     North American Vertical Datum              NAVD88 =  0.186
     MEAN LOW WATER                             MLW    =  0.033
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (10/13/1988)         =

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4336 E 1987                                 6.025    5.330
     92 W 1923 54                               16.410   15.715
     MIDDLETOWN 1935                            15.414   14.719
     Y 14 1935                                  10.229    9.534
     846 4336 NO STAMPING 1                     11.329   10.634


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  6

                                                                                
Station ID: 8464336                         PUBLICATION DATE:  06/23/2003
Name:       MIDDLETOWN, CONNECTICUT RIVER                     
            CT
NOAA Chart: 12377                           Latitude:   41° 33.6' N (  41.56000)
USGS Quad:  MIDDLETOWN                      Longitude:  72° 38.7' W ( -72.64500)


                             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.

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Products available at 8464336 MIDDLETOWN, CONNECTICUT RIVER, CT

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services