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Bench Mark Sheet for 8774230, Aransas Wildlife Refuge 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  6

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


To reach the station from Main Street in Austwell, travel 0.43 km (0.27 mi) SE
to FM 774, proceed south on FM 774 for 1.16 km (0.72 mi) to FM 2040, turn left
and travel south on FM 2040 for 10.27 km (6.38 mi) to the entrance of the
Aransas Wildlife Refuge.  From the check in office follow Park Road 13.11 km
(8.15 mi) to the facility boat ramp. The station is located at the end of the
canal leading to the ICWW. The bench marks are located on both sides of the
canal.


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


                 PRIMARY BENCH MARK STAMPING:  4230 B 2012
                         DESIGNATION:          877 4230 B

MONUMENTATION:           Metal Rod                             VM#:        20708
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 13.8' N (  28.22953)          LONGITUDE:  96° 47.8' W ( -96.79711)


The bench mark is a stainless steel rod located 95.6 m (313.5 ft) north of 877
4230 A, 88.2 m (289.3 ft) SE of bench mark 877 4230 C, 6.9 m (22.8 ft) NE of the
NE side of the channel, driven to refusal and encased in a 6 inch PVC pipe with
concrete kickblock.

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

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


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


                         BENCH MARK STAMPING:  4230 A  2012
                         DESIGNATION:          877 4230 A

MONUMENTATION:           Metal Rod                             VM#:        20707
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 13.7' N (  28.22867)          LONGITUDE:  96° 47.8' W ( -96.79708)


The bench mark is a stainless steel rod located, 95.6 m (313.5 ft) south of 877
4230 B, 4.24 m (13.9 ft) SW of the SW side of the channel, driven to refusal and
encased in a 6 inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  4230 C 2012
                         DESIGNATION:          877 4230 C

MONUMENTATION:           Metal Rod                             VM#:        20709
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 13.8' N (  28.23017)          LONGITUDE:  96° 47.9' W ( -96.79764)


The bench mark is a stainless steel rod located 93.13 (305.5 ft) SE of 877 4230
D, 88.2 m (289.3 ft) NW of bench mark 877 4230 B, 6.10 m (20.02 ft) NE of the NE
side of the channel, driven to refusal and encased in a 6 inch PVC pipe with
concrete kickblock.

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

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


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


                         BENCH MARK STAMPING:  4230 D 2012
                         DESIGNATION:          877 4230 D

MONUMENTATION:           Metal Rod                             VM#:        20710
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 13.9' N (  28.23089)          LONGITUDE:  96° 47.9' W ( -96.79814)


The bench mark is a stainless steel rod located 93.7 m (307.5 ft) NE of Bench
mark 877 4230 C, 82.02 m (269.1 ft) SE of 877 4230 E, 11.7 m (38.4 ft) NE of the
NE side of the channel, driven to refusal and encased in a 6 inch PVC pipe with
concrete kickblock.



                         BENCH MARK STAMPING:  4230 E 2012
                         DESIGNATION:          877 4230 E

MONUMENTATION:           Metal Rod                             VM#:        20711
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   28° 13.9' N (  28.23144)          LONGITUDE:  96° 47.9' W ( -96.79869)


The bench mark is a stainless steel rod located 105.7 m (346.9 ft) SE of bench
mark 90028 B, 82.02 m (269.1 ft) NW of 877 4230 D, 15 m (50.3 ft) NE of the SE
corner of boat barn, driven to refusal and encased in a 6 inch PVC pipe with
concrete kickblock.

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

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


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


                         BENCH MARK STAMPING:  B 1992
                         DESIGNATION:          877 90038 B

MONUMENTATION:           Survey disk                           VM#:        20712
AGENCY:                  CBI                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID#: DP0714
LATITUDE:   28° 13.9' N (  28.23228)          LONGITUDE:  96° 48.0' W ( -96.79922)


The bench mark is a stainless steel rod located 105.7 m (346.9 ft) NW of
benchmark 877 4230 E, 92 m (301.8 ft) north of north side of boat barn, driven
to refusal and encased in a 6 inch PVC pipe with concrete kickblock.

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

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


                            T I D A L   D A T U M S 


Tidal datums at ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           January 2016 - December 2016
     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)         =  1.572
     MEAN HIGHER HIGH WATER                     MHHW   =  0.096
     MEAN HIGH WATER                            MHW    =  0.094
     MEAN SEA LEVEL                             MSL    =  0.048
     MEAN TIDE LEVEL                            MTL    =  0.046
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     MEAN LOW WATER                             MLW    = -0.001
     LOWEST  OBSERVED WATER LEVEL (02/11/2016)         = -0.330

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4230 B 2012                                 1.180    1.086
     4230 A  2012                                0.244    0.150
     4230 C 2012                                 1.073    0.979
     4230 D 2012                                 0.832    0.738
     4230 E 2012                                 0.932    0.838
     B 1992                                      0.901    0.807


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

                                                                                
Station ID: 8774230                         PUBLICATION DATE:  05/09/2018
Name:       ARANSAS WILDLIFE REFUGE, SAN ANTONIO BAY          
            TX
NOAA Chart: 11315                           Latitude:   28° 13.7' N (  28.22756)
USGS Quad:  MESQUITE BAY                    Longitude:  96° 47.8' W ( -96.79656)


                             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 8774230 Aransas Wildlife Refuge, TX

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