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Superseded Bench Mark Sheet for 8771013, Eagle Point, Galveston Bay TX

Present Epoch

Printable version

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

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


To reach the tidal bench marks from the Post Office in San Leon, head 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
183 m (600 ft) 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 A 1992
                         DESIGNATION:          877 1013 A

MONUMENTATION:           Bench Mark disk                           VM#:    13445
AGENCY:                  Lamar Univ. Beaumont                      PID#:  AJ4424
SETTING CLASSIFICATION:  Stainless steel rod


The primary bench mark is a disk located east of Butlers on the Bay Motel near
the foot of a private pier, 40.51 m (132.9 ft) east of the centerline of 5th
Street, 3.69 m (12.1 ft) NE of the north edge of the private pier, 3.35 m (10.9
ft) SW of a fence, and 0.70 m (2.3 ft) WNW of the bulkhead.The bench mark is set
5 cm (0.2 ft) below ground level, crimped to a stainless steel rod driven 10.7 m
(35 ft) to refusal, and encased in a 6-inch PVC pipe with concrete kickblock.



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

MONUMENTATION:           Bench Mark disk                           VM#:    13446
AGENCY:                  Lamar Univ. Beaumont                      PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk located east of Butlers on the Bay Motel, 18.41 m (60.4
ft) SW of the SW corner of a house, 6.77 m (22.2 ft) ESE of the centerline of
5th Street, and 0.82 m (2.7 ft) NE of a wood utility pole.  The bench mark is
set 5 cm (0.2 ft) below ground level, crimped to a stainless steel rod driven
10.7 m (35 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

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


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


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

MONUMENTATION:           Bench Mark disk                           VM#:    13447
AGENCY:                  Lamar Univ. Beaumont                      PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk located 13.01 m (42.7 ft) NE of the NE corner of
Butlers on the Bay Motel, 10.24 m ( 33.6 ft) north of the centerline of a gravel
entrance to the motel parking area, 6.89 m (22.6 ft) west of the centerline of
5th Street, and 1.01 m (3.3 ft) SE of the end of a fence.  The bench mark is set
5 cm (0.2 ft) below ground level, crimped to a stainless steel rod driven 10.7 m
(35 ft) to refusal, and encased in a 6-inch PVC pipe with concrete kickblock.  



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

MONUMENTATION:           Bench Mark disk                           VM#:    13448
AGENCY:                  Lamar Univ. Beaumont                      PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk located 44 m (145 ft) NNE of bench mark LUB 1013 C
1992, 5.94 m (19.5 ft) east of the centerline of 5th Street, 1.52 m (5.0 ft) SW
of a utility (gas) meter, and 1.01 m (3.3 ft) NW of a wood utility pole.  The
bench mark is set 5 cm (0.2 ft) below ground level, crimped to a stainless steel
rod driven 10.7 m (35 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  3 of  6

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


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


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

MONUMENTATION:           Bench Mark disk                           VM#:    13449
AGENCY:                  Lamar Univ. Beaumont                      PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk located at the intersection of Avenue I and 5th Street,
11.49 m (37.7 ft) north of the centerline of Avenue I, 7.28 m (23.9 ft) west of
the centerline of 5th Street, and 0.73 m (2.4 ft) SSW of a wood utility pole. 
The bench mark is set 5 cm (0.2 ft) below ground level, crimped to a stainless
steel rod driven 10.7 m (35 ft) to refusal, and encased in a 6-inch PVC pipe
with concrete kickblock.



                         BENCH MARK STAMPING:  EAGLE PT NO 2 1932
                         DESIGNATION:          EAGLE POINT RM 2

MONUMENTATION:           Reference Mark disk                       VM#:    13450
AGENCY:                  USC&GS                                    PID#:  AW1602
SETTING CLASSIFICATION:  Set into the top of a concrete monument


The bench mark is a disk set in top of a concrete post at the intersection of
3rd Street and Avenue B at San Leon, 20.57 m (67.5 ft) SW of SW corner of a
house, 9.14 m (30.0 ft) east of centerline of 3rd Street, 8.84 m (29.0 ft) north
of the centerline of Avenue B, 3.20 m (10.5 ft) NE of a combination power and
telephone pole, and 0.09 m (0.3 ft) above ground level.

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

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


                            T I D A L   D A T U M S 


Tidal datums at EAGLE POINT, GALVESTON BAY based on:

     LENGTH OF SERIES:      57 MONTHS
     TIME PERIOD:           October 1993 - June 1998
     TIDAL EPOCH:           1960-1978
     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 (10/06/1996)         =  1.082
     MEAN HIGHER HIGH WATER                     MHHW   =  0.336
     MEAN HIGH WATER                            MHW    =  0.323
     MEAN SEA LEVEL                             MSL    =  0.189
     MEAN TIDE LEVEL                            MTL    =  0.174
     MEAN LOW WATER                             MLW    =  0.025
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (12/29/1997)         = -1.109

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     LUB 1013 A 1992                             1.463    1.140
     LUB 1013 B 1992                             2.696    2.373
     LUB 1013 C 1992                             2.602    2.279
     LUB 1013 D 1992                             2.590    2.267
     LUB 1013 E 1992                             2.544    2.221
     EAGLE PT NO 2 1932                          3.085    2.762


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

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


Foot Notes:

Galveston Bay, Texas has anomalous relative sea level trends compared to most
other geographic regions in the United States. This is due to a general
subsidence of land in this area, which has been occurring at a rapid rate.
Because of the magnitude of the sea level trends in these areas, NOAA has
adopted a procedure for computing accepted tidal datums for the National Water
Level Observation Network (NWLON) using the last several years of sea level data
rather than the 19-year tidal epoch. The tide ranges are still based on the 1960
- 1978  National Tidal Datum Epoch (NTDE) and are applied to the 5  year (1990 -
1994) mean tide level (MTL) to compute other tidal datums. The adoption of this
procedure was necessary to ensure that these tidal datums accurately represent
the existing stand of sea level.

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

                                                   PUBLICATION DATE:  01/14/2000
Station ID: 8771013                                SUPERCEDED DATE:   04/21/2003
Name:       EAGLE POINT, GALVESTON BAY                        
            TEXAS
NOAA Chart: 11327                                  Latitude:         29° 28.8' N
USGS Quad:  TEXAS CITY                             Longitude:        94° 55.1' W


                             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 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
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