Bench Mark Sheet for 8771972, San Luis Pass 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Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


The station is located at 14001 County Rd 257, Freeport, TX 77541 at San Luis
Pass County Park.


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


                 PRIMARY BENCH MARK STAMPING:  1972 M 2010
                         DESIGNATION:          877 1972 M

MONUMENTATION:           Metal Rod                             VM#:        20478
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID#: DP0696
LATITUDE:   29°  4.8' N (  29.08019)          LONGITUDE:  95°  7.9' W ( -95.13222)


The bench mark is a stainless steel deep-rod encased in 6 inch PVC with concrete
kickblock.  The bench mark is located 148 m (485.6 ft) SW of the tide station,
21.3 m (69.9 ft) SW of the south corner of the restroom building, 14.19 m (46.5
ft) west of a light pole, and 7.0 m (22.9 ft) SW of a concrete drain cap
numbered V-1418.  The stainless steel rod is driven 17.1 m (56 ft) into the
ground.  The mark is flush with ground level.  

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

                                                                                
Station ID: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


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


                         BENCH MARK STAMPING:  1972 N 2010
                         DESIGNATION:          877 1972 N 2010

MONUMENTATION:           Metal Rod                             VM#:        21992
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   29°  4.8' N (  29.07967)          LONGITUDE:  95°  7.9' W ( -95.13092)


The bench mark is a metal rod encased in a 6" PVC pipe with concrete kickblock. 
The bench mark is located 8.0 m (26.2 ft) north of the centerline of road on the
island, 4.52 m (14.83 ft) east of light pole with street light, and 1.7 m (5.6
ft) NNE  of a 1.5 m (4.9 ft) x 1.5 m (4.9 ft) concrete 480 volt conduit that
houses power to the RV park. The mark is a stainless steel deep-rod driven to
refusal to a depth of 17.1 m (56 ft ).



                         BENCH MARK STAMPING:  1972 I 2009
                         DESIGNATION:          877 1972 I

MONUMENTATION:           Bench Mark disk                       VM#:        21993
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   29°  4.8' N (  29.07936)          LONGITUDE:  95°  7.8' W ( -95.13053)


The bench mark is a brass disk on a concrete bulkhead, located 62 m (203.4 ft)
north of the boat ramp on the bulkhead, 22.3 m (73.2 ft) NW of the most southern
corner of the laundry room, and 27.6 m (90.5 ft) west of the electronic gate
keypad.

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

                                                                                
Station ID: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


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


                         BENCH MARK STAMPING:  1972 J 2009
                         DESIGNATION:          877 1972 J

MONUMENTATION:           Bench Mark disk                       VM#:        21994
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   29°  4.7' N (  29.07906)          LONGITUDE:  95°  7.8' W ( -95.13000)


The bench mark is a disk located 27 m (88.6 ft) south of the center line of San
Luis Pass Park road, 16 m (52.5 ft) east of the east of the administration
building, and 4 m (13.1 ft) west of the west side of cabins 1 and 2 building.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          877 1972 P 2010

MONUMENTATION:           Metal Rod                             VM#:        21995
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   29°  4.8' N (  29.07944)          LONGITUDE:  95°  7.8' W ( -95.12958)


The bench mark is a stainless steel deep-rod encased in a 6" PVC pipe with a
concrete kickblock.  The bench mark is located 16.64 m (54.59 ft) SW of a Marlin
Open Pavillion, 11.0 m (36.1 ft) east of an elevated well house, and 4.85 m
(15.9 ft) east of centerline of Park Entrance Road.  The stainless steel rod is
driven 17.1 m (56 ft) to refusal.

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

                                                                                
Station ID: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


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


                         BENCH MARK STAMPING:  1972 K 2009
                         DESIGNATION:          877 1972 K

MONUMENTATION:           Metal Rod                             VM#:        21996
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID#: BBBS79
LATITUDE:   29°  4.7' N (  29.07756)          LONGITUDE:  95°  7.7' W ( -95.12772)


The bench mark is a stainless steel rod encased in 6 inch PVC pipe with a
concrete kickblock on the NW side of wooden barriers and marked with a
fiberglass witness post.  The bench mark is located 64 m (209.9 ft) west of the
centerline of the highway and 3 m (9.8 ft) from centerline of the road entering
into the park.  The stainless steel rod is driven to a depth of 13.4 m (44 ft).



                         BENCH MARK STAMPING:  1972 G 2009
                         DESIGNATION:          877 1972 G

MONUMENTATION:           Bench Mark disk                       VM#:        21997
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   29°  4.9' N (  29.08094)          LONGITUDE:  95°  7.9' W ( -95.13128)


The bench mark is a disk set in concrete bulkhead.  The bench mark is located
35.46 m (116.34 ft) north west of tide gauge on concrete bulkhead, 25.4 m (83.3
ft) ESE of light pole, 13.3 m (43.6 ft) SE of the west corner of the end of the
bulkhead.  

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

                                                                                
Station ID: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


                            T I D A L   D A T U M S 


Tidal datums at SAN LUIS PASS, WEST BAY based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           October 2016 - September 2017
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8772447 FREEPORT, FREEPORT HARBOR CHANNEL


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

     HIGHEST OBSERVED WATER LEVEL (08/25/2017)         =  1.326
     MEAN HIGHER HIGH WATER                     MHHW   =  0.381
     MEAN HIGH WATER                            MHW    =  0.360
     MEAN SEA LEVEL                             MSL    =  0.220
     MEAN TIDE LEVEL                            MTL    =  0.205
     North American Vertical Datum              NAVD88 =  0.121
     MEAN LOW WATER                             MLW    =  0.050
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/12/2018)         = -0.821

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1972 M 2010                                 0.937    0.577
     1972 N 2010                                 0.997    0.637
     1972 I 2009                                 1.374    1.014
     1972 J 2009                                 1.791    1.431
     877 1972 P 2010                             2.026    1.666
     1972 K 2009                                 0.975    0.615
     1972 G 2009                                 1.643    1.283


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

                                                                                
Station ID: 8771972                         PUBLICATION DATE:  05/10/2018
Name:       SAN LUIS PASS, WEST BAY                           
            TX
NOAA Chart: 11322                           Latitude:   29°  4.9' N (  29.08097)
USGS Quad:  CHRISTMAS POINT                 Longitude:  95°  7.9' W ( -95.13133)


                             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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