U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


To reach the tidal bench marks from the intersection of Texas State Highway 146
and W. Barbours Cut Boulevard in La Porte, proceed east on W. Barbours Cut
Boulevard for approximately 0.8 km (0.5 mi) to the point where W. Barbours Cut
Boulevard becomes E. Barbours Cut Boulevard, then continue east on E. Barbours
Cut Boulevard for 3.2 km (2.0 mi) to the Port of Houston Authority entrance
gates, then continue through the gates and bear left, crossing the railroad
tracks, and then proceed to the U-shaped concrete dock on the ship channel.  The
bench marks are located in the vicinity of the Port of Houston Authority
property.  The tide gage and staff are located on a small wooden dock on the
east side of the concrete dock.  Closest access to the station is Gate 4.  Once
inside proceed north to the bank, the station is located on a u-shaped pier. 
Contact Anthony Flenoy (Security Manager) at 713-670-3663 for any access issues.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


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


                 PRIMARY BENCH MARK STAMPING:  E 1201 1973
                         DESIGNATION:          E 1201

MONUMENTATION:           Bench Mark disk                       VM#:        11218
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AW1556
SETTING CLASSIFICATION:  Concrete bridge abutment              OPUS PID:        
LATITUDE:   29° 40.9' N (  29.68133)          LONGITUDE:  94° 59.1' W ( -94.98539)


The bench mark is a disk set in top of the east end of the south concrete
abutment of the most westerly bridge of the Houston Port Authority Container
Terminal Dock, 84 m (276 ft) NW of the centerline of Morgans Point-La Porte
Road, 0.37 m (1.2 ft) east of the SE corner of a concrete walkway, and 0.3 m (1
ft) above the bridge floor.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


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


                         BENCH MARK STAMPING:  MORGAN PT 3 USE NO 3 1973
                         DESIGNATION:          MORGAN PT 3 RM 3

MONUMENTATION:           Reference Mark disk                   VM#:        11214
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AW1554
SETTING CLASSIFICATION:  Curb                                  OPUS PID:        
LATITUDE:   29° 40.9' N (  29.68142)          LONGITUDE:  94° 59.1' W ( -94.98542)


The bench mark is a disk set on the top center of the east curb of the west
bridge to the Houston Port Authority Container Terminal Dock at Morgans Point,
10.88 m (35.7 ft) NE of Bench Mark MORGAN POINT 3 USE, and 9.91 m (32.5 ft)
north of the entrance to the west bridge of the dock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


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


                         BENCH MARK STAMPING:  MORGAN PT 3 USE 1973
                         DESIGNATION:          MORGAN PT 3

MONUMENTATION:           Triangulation Station disk            VM#:        11215
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  AW1555
SETTING CLASSIFICATION:  Head wall                             OPUS PID#: AW1555
LATITUDE:   29° 40.9' N (  29.68131)          LONGITUDE:  94° 59.1' W ( -94.98544)


The bench mark is a disk set in the south end of the west wing of the head wall
of the west bridge to the Houston Port Authority Container Terminal Dock, and 1
m (2 ft) higher than the ramp leading to the dock.



                         BENCH MARK STAMPING:  0613 H 2004
                         DESIGNATION:          877 0613 H TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        17724
AGENCY:                  Division of Nearshore Research        IDB PID#:        
SETTING CLASSIFICATION:  Pier                                  OPUS PID#: BBGD01
LATITUDE:   29° 40.9' N (  29.68144)          LONGITUDE:  94° 59.1' W ( -94.98461)


The bench mark is located 47.0 m (154.2 ft) SSW of the SW corner of a U-shaped
concrete pier, 16.0 m (52.50 ft) W of the centerline of the paved road leading
to the pier, 0.67 m (2.20 ft) SW of the SE corner of the Port of Houston
Authority Fire Station, and 0.34 m (1.12 ft) S of the south face of the fire
station.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


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


                         BENCH MARK STAMPING:  877 0613 K 2018
                         DESIGNATION:          877 0613 K

MONUMENTATION:           Metal Rod                             VM#:        22711
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 40.9' N (  29.68147)          LONGITUDE:  94° 59.1' W ( -94.98436)


The mark is located 18.20 m (59.7 ft) NNE of west corner of fire deptment
building, 17.40 m (57.1 ft) east of the east bulkhead corner of dock entrance,
11.61 m (38.1 ft) NNW of southern most powerpole on the north side of the fire
dept building, 4.18 m (13.7 ft) east of the eastern corner of concrete walkway
leading to fire boat. The benchmark is set flush with the ground, crimped to a
stainless steel rod driven 15.8 m (51.8 ft) to refusal and encased in a 6-incn
PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  877 0613 M 2018
                         DESIGNATION:          877 0613 M

MONUMENTATION:           Metal Rod                             VM#:        22712
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: BBGS59
LATITUDE:   29° 40.9' N (  29.68147)          LONGITUDE:  94° 59.0' W ( -94.98389)


The mark is located 38.80 m (127.3 ft) east of the NW corner of the concrete
parking lot east of the fire dept building, 30.00 m (98.4 ft) south of southern
most shore piling on the north/south running fence line, 11.00 m (36.1 ft) south
of powerpole along the chainlink fence line, 1.01 m  (3.3 ft) west of the
chainlink fence running north/south, 1.01 m (3.3 ft) north of the chainlink
fence running east/west. The benchmark is set flush with the ground, crimped to
a stainless steel rod driven 17.1 m (56 ft) to refusal, encased in 6 in PVC pipe
with concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


                            T I D A L   D A T U M S 


Tidal datums at MORGANS POINT, BARBOURS CUT based on:

     LENGTH OF SERIES:      21 YEARS
     TIME PERIOD:           April 1997 - October 2019
     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 (09/12/2008)         =  2.017
     MEAN HIGHER HIGH WATER                     MHHW   =  0.406
     MEAN HIGH WATER                            MHW    =  0.384
     MEAN SEA LEVEL                             MSL    =  0.222
     MEAN TIDE LEVEL                            MTL    =  0.211
     MEAN LOW WATER                             MLW    =  0.038
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.004
     LOWEST  OBSERVED WATER LEVEL (01/19/1996)         = -0.998

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     E 1201 1973                                 4.421    4.037
     MORGAN PT 3 USE NO 3 1973                   4.438    4.054
     MORGAN PT 3 USE 1973                        4.428    4.044
     0613 H 2004                                 4.374    3.990
     877 0613 K 2018                             4.691    4.307
     877 0613 M 2018                             5.226    4.842


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 8770613                         PUBLICATION DATE:  12/14/2020
Name:       MORGANS POINT, BARBOURS CUT                       
            TX
NOAA Chart: 11328                           Latitude:   29° 40.9' N (  29.68169)
USGS Quad:  TEXAS CITY                      Longitude:  94° 59.1' W ( -94.98500)


                             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.