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Bench Mark Sheet for 8771013, Eagle Point, Galveston Bay 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Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


To reach the tidal bench marks from the Post Office in San Leon, proceed south
on 9th Street for 1.4 km (0.9 mi) to Avenue I, then turn east on Avenue I for
0.6 km (0.4 mi) to 5th Street, then turn south on 5th Street and go
approximately 0.2 km (0.1 mi) to "Butler's on the Bay" hotel.  The bench marks
are located in the vicinity of the pier and along 5th Street.  The tide gauge is
located on the pier opposite the hotel, mounted on a square galvanized steel
structure.


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


                 PRIMARY BENCH MARK STAMPING:  LUB 1013 B 1992
                         DESIGNATION:          877 1013 B
                         ALIAS:                1013 B

MONUMENTATION:           Bench Mark disk                       VM#:        13446
AGENCY:                  Lamar University                      IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 28.8' N (  29.48067)          LONGITUDE:  94° 55.1' W ( -94.91908)


The primary bench mark is a disk located east of Butlers on the Bay Motel, 18.41
m (60.40 ft) SW of the SW corner of a house, 6.77 m (22.21 ft) ESE of the
centerline of 5th Street, and 0.82 m (2.69 ft) NE of a wood utility pole.  The
bench mark is set 5 cm below ground level, crimped to a stainless steel rod
driven 10.7 m (35.1 ft) 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: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


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


                         BENCH MARK STAMPING:  LUB 1013 A 1992
                         DESIGNATION:          877 1013 A
                         ALIAS:                1013 A

MONUMENTATION:           Bench Mark disk                       VM#:        13445
AGENCY:                  Lamar University                      IDB PID#:  AJ4424
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AJ4424
LATITUDE:   29° 28.8' N (  29.48067)          LONGITUDE:  94° 55.1' W ( -94.91869)


The bench mark is a disk located east of Butlers on the Bay Motel near the foot
of a private pier, 40.51 m (132.91 ft) east of the centerline of 5th Street,
3.69 m (12.11 ft) NE of the north edge of the private pier, 3.35 m (10.99 ft) SW
of a fence, and 0.70 m (2.30 ft) WNW of the bulkhead.  The bench mark is set 5
cm below ground level, crimped to a stainless steel rod driven 10.7 m (35.1ft)
to refusal, and encased in a 6-inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  LUB 1013 C 1992
                         DESIGNATION:          877 1013 C
                         ALIAS:                1013 C

MONUMENTATION:           Bench Mark disk                       VM#:        13447
AGENCY:                  Lamar University                      IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 28.9' N (  29.48114)          LONGITUDE:  94° 55.1' W ( -94.91906)


The bench mark is a disk located 13.01 m (42.68 ft) NE of the NE corner of
Butlers on the Bay Motel, 10.24 m ( 33.60 ft) north of the centerline of a
gravel entrance to the motel parking area, 6.89 m (22.60 ft) west of the
centerline of 5th Street, and 1.01 m (3.31 ft) SE of the end of a fence.  The
bench mark is set 5 cm below ground level, crimped to a stainless steel rod
driven 10.7 m (35.1ft) 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: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


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


                         BENCH MARK STAMPING:  LUB 1013 D 1992
                         DESIGNATION:          877 1013 D
                         ALIAS:                1013 D

MONUMENTATION:           Bench Mark disk                       VM#:        13448
AGENCY:                  Lamar University                      IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 28.9' N (  29.48153)          LONGITUDE:  94° 55.1' W ( -94.91882)


The bench mark is a disk located 44 m (144.4 ft) NNE of bench mark LUB 1013 C
1992, 5.94 m (19.49 ft) east of the centerline of 5th Street, 1.52 m (4.987 ft)
SW of a utility (gas) meter, and 1.01 m (3.31 ft) NW of a wood utility pole. 
The bench mark is set 5 cm below ground level, crimped to a stainless steel rod
driven 10.7 m (35.1 ft) to refusal, and encased in a 6-inch PVC pipe with
concrete kickblock.



                         BENCH MARK STAMPING:  LUB 1013 E 1992
                         DESIGNATION:          877 1013 E
                         ALIAS:                1013 E

MONUMENTATION:           Bench Mark disk                       VM#:        13449
AGENCY:                  Lamar University                      IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 28.9' N (  29.48238)          LONGITUDE:  94° 55.1' W ( -94.91872)


The bench mark is a disk located at the intersection of Avenue I and 5th Street,
0.75 m (2.46 ft) 175 Deg from a power pole, 6.1 m (20.01 ft) 125 DEG from the SE
corner of 848 TH ST. 6.7 m (21.98 ft) 285 DEG from the centerline of 5 TH ST,
and 7.16 m (23.49 ft) 355 DEG from a manhole on avenue I.  The bench mark is a
brass disk crimped to a stainless rod driven to refusal.  The bench mark is
encased in a 6 inch PVC pipe and concrete kick block set flush with the ground. 

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

                                                                                
Station ID: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


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


                         BENCH MARK STAMPING:  1013 F 2002
                         DESIGNATION:          877 1013 F
                         ALIAS:                1013 F

MONUMENTATION:           Bench Mark disk                       VM#:        16721
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   29° 28.9' N (  29.48175)          LONGITUDE:  94° 55.1' W ( -94.91803)


The bench mark is a brass surface disk set in the concrete sidewalk that runs
along the bulkhead located on the sidewalk at the bulkhead of 909 5th street in
San Leon.  The bench mark 0.22m (0.7 ft) NW of th edge SE edge of the bulkhead,
3.0m (9.8 ft) SE of a flag pole, 6.1m (2.0 ft) south of the SW corner of a
(0.60m) 2 ft cube of concrete, and 6.1m (2.0 ft) north of the base of a 106.68m
(350 ft) wooden pier.

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

                                                                                
Station ID: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


                            T I D A L   D A T U M S 


Tidal datums at EAGLE POINT, GALVESTON BAY based on:

     LENGTH OF SERIES:      15 YEARS
     TIME PERIOD:           Sep 1994 - Aug 2008 + Mar 2010 - Feb 2011
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8771450 GALVESTON PIER 21, GALVESTON CHANNEL


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

     HIGHEST OBSERVED WATER LEVEL (09/13/2008)         =  3.619
     MEAN HIGHER HIGH WATER                     MHHW   =  0.338
     MEAN HIGH WATER                            MHW    =  0.325
     MEAN SEA LEVEL                             MSL    =  0.182
     MEAN TIDE LEVEL                            MTL    =  0.170
     MEAN LOW WATER                             MLW    =  0.016
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (12/29/1997)         = -1.177

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     LUB 1013 B 1992                             2.628    2.303
     LUB 1013 A 1992                             1.394    1.069
     LUB 1013 C 1992                             2.536    2.211
     LUB 1013 D 1992                             2.524    2.199
     LUB 1013 E 1992                             2.478    2.153
     1013 F 2002                                 2.360    2.035


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

                                                                                
Station ID: 8771013                         PUBLICATION DATE:  07/14/2011
Name:       EAGLE POINT, GALVESTON BAY                        
            TX
NOAA Chart: 11327                           Latitude:   29° 28.8' N (  29.48000)
USGS Quad:  TEXAS CITY                      Longitude:  94° 55.1' W ( -94.91830)


                             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 8771013 Eagle Point, Galveston Bay, TX

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