Superseded Bench Mark Sheet for 8770733, Lynchburg Landing TX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:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' W


To reach the tidal bench marks from the Post Office in Highlands, travel south
on Crosby-Lynchburg Road for 5.8 km (3.6 mi) to Lynchburg Ferry Landing.  The
bench marks are located around the ferry landing.  The tide gage and staff were
on Old Ferry Landing, now in ruins.


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


                 PRIMARY BENCH MARK STAMPING:  LUB 0733 C 1995
                         DESIGNATION:          877 0773 C

MONUMENTATION:           Survey disk                               VM#:    16091
AGENCY:                  Lamar University Beaumont (LUB)           PID#:  AJ4423
SETTING CLASSIFICATION:  Stainless steel rod


The primary bench mark is a disk set in the east side of the Lynchburg Landing
Ferry compound, 25.51 m (83.7 ft) NW of a fence on the SE side of the compound,
10.88 m (35.7 ft) WSW of the NE corner of the main ferry building, and 4.81 m
(15.8 ft) ENE of the SE corner of the main building. The bench mark is crimped
to a stainless steel rod driven 16.8 m (55 ft) to refusal, and encased in a
6-inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  C 1277 1978
                         DESIGNATION:          C 1277

MONUMENTATION:           Bench Mark disk                           VM#:    11774
AGENCY:                  National Geodetic Survey (NGS)            PID#:  AW0942
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk set inside the Lynchburg Ferry compound, 32.92 m (108.0
ft) east of the centerline of the Crosby Lynchburg Road, 29.66 m (97.3 ft) NE of
the NE corner of the main building, 9.02 m (29.6 ft) west of the chain link
fence around the compound, 0.46 m (1.5 ft) east of a utility pole, and 0.21 m
(0.7 ft) north of a witness post.  The bench mark is set 0.12 m (0.4 ft) below
ground, crimped to an stainless steel rod driven 14.6 m (48 ft), and encased in
a 5-inch NGS logo cap.

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

                                                   PUBLICATION DATE:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' W


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


                         BENCH MARK STAMPING:  0733 A 1983
                         DESIGNATION:          877 0733 A

MONUMENTATION:           Tidal Station disk                        VM#:    11775
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Concrete foundation


The bench mark is a disk set in the SW corner of 2 m x 2 m (6 ft x 8 ft)
concrete foundation for a pressure tank near the Civil Defense Power Station,
23.71 m (77.8 ft) north of the centerline of Crosby Lynchburg Road, 10.36 m
(34.0 ft) SE of SW corner of the Civil Defense tower fence, and 0.27 m (0.9 ft)
north of the south edge of the concrete foundation.



                         BENCH MARK STAMPING:  LUB 0733 D 1995
                         DESIGNATION:          877 0773 D

MONUMENTATION:           Survey disk                               VM#:    16092
AGENCY:                  Lamar University Beaumont (LUB)           PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk set in the east side of the Lynchburg Landing Ferry
compound, 12.19 m (40.0 ft)  NNW of the NW corner of the main ferry building,
11.61 m (38.1 ft) south of the centerline of Crosby Lynchburg Road, and 2.56 m
(8.4 ft) WSW of a flag pole. The bench mark is crimped to a stainless steel rod
driven 16.8 m (55 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:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' W


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


                         BENCH MARK STAMPING:  LUB 0733 E 1995
                         DESIGNATION:          877 0773 E

MONUMENTATION:           Survey disk                               VM#:    16093
AGENCY:                  Lamar University Beaumont (LUB)           PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk set at the NW corner of the ferry maintenance building
in the east side of the Lynchburg Landing Ferry compound, 22.89 m (75.10 ft) SSE
of the centerline of Crosby Lynchburg Road, 15.79 m (51.8 ft)  west of the NE
corner of the maintenance building, 2.74 m (9.0 ft) NW of the NW corner of the
maintenance building, and 0.61 m (2.0 ft) south of the corner of a fence. The
bench mark is crimped to a stainless steel rod driven 16.8 m (55 ft) to refusal,
and encased in a 6-inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  LUB 0733 F 1995
                         DESIGNATION:          877 0773 F

MONUMENTATION:           Survey disk                               VM#:    16094
AGENCY:                  Lamar University Beaumont (LUB)           PID:         
SETTING CLASSIFICATION:  Stainless steel rod


The bench mark is a disk set along the north side of Crosby Lynchburg Road near
the east side of the Lynchburg Landing Ferry compound, 38.95 m (127.8 ft) NNW of
the NW corner of the ferry maintenance building, 8.02 m (26.3 ft) NNW of Crosby
Lynchburg Road, and 0.67 m (2.2 ft) SE of a wood utility pole. The bench mark is
crimped to a stainless steel rod driven 16.8 m (55 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  4 of  6

                                                   PUBLICATION DATE:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' W


                            T I D A L   D A T U M S 


Tidal datums at LYNCHBURG LANDING, SAN JACINTO R. based on:

     LENGTH OF SERIES:      1 YEAR
     TIME PERIOD:           January 1996 - December 1996
     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 (11/16/1996)         =  1.117
     MEAN HIGHER HIGH WATER                     MHHW   =  0.432
     MEAN HIGH WATER                            MHW    =  0.406
     MEAN SEA LEVEL                             MSL    =  0.242
     MEAN TIDE LEVEL                            MTL    =  0.237
     MEAN LOW WATER                             MLW    =  0.069
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/19/1996)         = -1.019

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     LUB 0733 C 1995                             2.178    1.772
     C 1277 1978                                 0.989    0.583
     0733 A 1983                                 1.748    1.342
     LUB 0733 D 1995                             2.118    1.712
     LUB 0733 E 1995                             1.282    0.876
     LUB 0733 F 1995                             0.775    0.369


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

                                                   PUBLICATION DATE:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' 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 the 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
Lvevel Observation Network (NWLON) using the last several years of sea level
data rather than the 1960 - 1978 tidal epoch. The tide ranges are still based on
the 1960 - 1978 National Tidal Datum Epoch (NTDE) and are applied to the five
year (1990 - 1994) mean tide level (MTL) to compute the other tidal datums. The
adoption of this procedure was necessary to assure 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:  08/02/2000
Station ID: 8770733                                SUPERCEDED DATE:   04/21/2003
Name:       LYNCHBURG LANDING, SAN JACINTO R.                 
            TEXAS
NOAA Chart: 11326                                  Latitude:         29° 45.9' N
USGS Quad:  HIGHLANDS                              Longitude:        95°  4.7' 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.

Return to Top
Products available at 8770733 Lynchburg Landing, TX