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Bench Mark Sheet for 8773146, Matagorda City TX

Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8773146                         PUBLICATION DATE:  10/05/2017
Name:       MATAGORDA CITY                                    
            TX
NOAA Chart: 11319                           Latitude:   28° 42.6' N (  28.71006)
USGS Quad:  MATAGORDA                       Longitude:  95° 54.8' W ( -95.91400)


Need boat to access station on ICWW.  Head northeast on ICWW out of Matagorda
Harbor (189 County Rd 213, Matagorda, TX 77457) for approximately 2 miles, and
the station will be on the northwest bank.  Station is a four pile wooden
structure.  For chartering a boat, contact Captain Charlie Paradoski at
713-725-2401.


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


                 PRIMARY BENCH MARK STAMPING:  3146 B 2012
                         DESIGNATION:          877 3146 B

MONUMENTATION:           Metal Rod                             VM#:        20597
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: DP0706
LATITUDE:   28° 42.6' N (  28.71056)          LONGITUDE:  95° 54.9' W ( -95.91517)


The bench mark is a stainless steel deep rod mark located 64.62 m (212.0 ft)
east of historical marker, 26.71 m (87.6 ft) SW of a power pole, 9.6 m (31.5 ft)
west of the fence line on the east side, and 5.64 m (18.5 ft) south of the
centerline of the street.  The bench mark is driven until refusal to a depth of
12.4 m and encased in a 6 inch (15 cm) PVC pipe with a concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8773146                         PUBLICATION DATE:  10/05/2017
Name:       MATAGORDA CITY                                    
            TX
NOAA Chart: 11319                           Latitude:   28° 42.6' N (  28.71006)
USGS Quad:  MATAGORDA                       Longitude:  95° 54.8' W ( -95.91400)


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


                         BENCH MARK STAMPING:  3146 A  2012
                         DESIGNATION:          877 3146 A

MONUMENTATION:           Bench Mark disk                       VM#:        20596
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 42.6' N (  28.71083)          LONGITUDE:  95° 54.9' W ( -95.91422)


The bench mark is a brass survey disk set in the bridge at Matagorda City, TX.
The bench mark is located 3.35 m (11.0 ft) east of the centerline of the bridge,
1.52 m (5.0 ft) south of the north end of the concrete bridge, and 0.3 m (1.0
ft) west of the east edge of the bridge.  The bench mark is set flush in the
bridge.



                         BENCH MARK STAMPING:  3146 C 2012
                         DESIGNATION:          877 3146 C

MONUMENTATION:           Metal Rod                             VM#:        20598
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 42.6' N (  28.71028)          LONGITUDE:  95° 55.0' W ( -95.91611)


The bench mark is a stainless steel deep rod mark located 31.1 m (102.0 ft) east
from the Battle Island historical marker, 26.6 m (87.3 ft) from power pole,  and
9.75 m (32.0 ft) to a private fence line bearing 335 degrees west of an H brace
in the fence line. The bench mark is driven until refusal encased in a 6 inch
(15 cm) PVC pipe with a concrete kick block.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8773146                         PUBLICATION DATE:  10/05/2017
Name:       MATAGORDA CITY                                    
            TX
NOAA Chart: 11319                           Latitude:   28° 42.6' N (  28.71006)
USGS Quad:  MATAGORDA                       Longitude:  95° 54.8' W ( -95.91400)


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


                         BENCH MARK STAMPING:  3146 D 2012
                         DESIGNATION:          877 3146 D

MONUMENTATION:           Metal Rod                             VM#:        20599
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 42.6' N (  28.70997)          LONGITUDE:  95° 55.0' W ( -95.91706)


The bench mark is a stainless steel deep rod located 30.9 m (101.4 ft) bearing
212 degrees from the power pole, 8.8 m (28.9 ft) from the fence line, and 6.1 m
(20.0 ft) SSE from the centerline of the road.  The bench mark is a driven until
refusal and encased in a 6 inch (15 cm) PVC pipe with a concrete kick block.



                         BENCH MARK STAMPING:  3146 E 2012
                         DESIGNATION:          877 3146 E

MONUMENTATION:           Metal Rod                             VM#:        20600
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 42.6' N (  28.70969)          LONGITUDE:  95° 55.1' W ( -95.91797)


The bench mark is a deep rod mark located 91.74 m (301.0 ft) south of 3146 D
2012, 32 m (105.0 ft) from a power pole, and 7.8 m (25.6 ft) to a private fence
.  The bench mark is driven until refusal encased in a 6 inch (15 cm) PVC pipe
with a concrete kick block.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8773146                         PUBLICATION DATE:  10/05/2017
Name:       MATAGORDA CITY                                    
            TX
NOAA Chart: 11319                           Latitude:   28° 42.6' N (  28.71006)
USGS Quad:  MATAGORDA                       Longitude:  95° 54.8' W ( -95.91400)


                            T I D A L   D A T U M S 


Tidal datums at MATAGORDA CITY based on:

     LENGTH OF SERIES:      11 Months
     TIME PERIOD:           6/2016-8/2016 & 10/2016-5/2017
     TIDAL EPOCH:           2002-2006
     CONTROL TIDE STATION:  8774770 ROCKPORT, ARANSAS BAY


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

     HIGHEST OBSERVED WATER LEVEL (08/26/2017)         =  1.067
     MEAN HIGHER HIGH WATER                     MHHW   =  0.129
     MEAN HIGH WATER                            MHW    =  0.127
     MEAN SEA LEVEL                             MSL    =  0.078
     MEAN TIDE LEVEL                            MTL    =  0.064
     MEAN LOW WATER                             MLW    =  0.002
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/23/2016)         = -0.326

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     3146 B 2012                                 0.594    0.467
     3146 A  2012                                1.534    1.407
     3146 C 2012                                 0.626    0.499
     3146 D 2012                                 0.595    0.468
     3146 E 2012                                 0.617    0.490


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

                                                                                
Station ID: 8773146                         PUBLICATION DATE:  10/05/2017
Name:       MATAGORDA CITY                                    
            TX
NOAA Chart: 11319                           Latitude:   28° 42.6' N (  28.71006)
USGS Quad:  MATAGORDA                       Longitude:  95° 54.8' W ( -95.91400)


                             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 8773146 Matagorda City, TX

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services