U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8772985                         PUBLICATION DATE:  12/30/2020
Name:       SARGENT, ICWW                                     
            TX
NOAA Chart: 11319                           Latitude:   28° 46.3' N (  28.77142)
USGS Quad:  CEDAR LAKES WEST                Longitude:  95° 37.0' W ( -95.61717)


To reach the station from the intersection of Farm to Market Road 457 and State
Highway 35 in Bay City, Texas, proceed east on Farm to Market Road 457 for 27.5
mi (44.2 km) to the Intercoastal Waterway.  The station is located near the west
bank of the Intercoastal Water Way before the bridge to cross to Sargent Beach.
The benchmarks are located on both sides of FM 457 near the swing bridge office
and marina across the street.


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


                 PRIMARY BENCH MARK STAMPING:  2985 E 2012
                         DESIGNATION:          877 2985 E

MONUMENTATION:           Flange-encased Rod                    VM#:        20704
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: BBGD51
LATITUDE:   28° 46.3' N (  28.77158)          LONGITUDE:  95° 37.1' W ( -95.61853)


The primary benchmark is a stainless steel deep rod located 78.02 m (256 ft)
west of the centerline of FM 457, 29.95 m (98.3 ft) SW of telephone pole marked
04, 17.7 m north of the corner of the concrete bulkhead. The deep rod benchmark
is driven 21.95 m (72.0 ft) until refusal and encased in a 15 cm (6 in) PVC pipe
with a concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8772985                         PUBLICATION DATE:  12/30/2020
Name:       SARGENT, ICWW                                     
            TX
NOAA Chart: 11319                           Latitude:   28° 46.3' N (  28.77142)
USGS Quad:  CEDAR LAKES WEST                Longitude:  95° 37.0' W ( -95.61717)


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


                         BENCH MARK STAMPING:  2985 A 2012
                         DESIGNATION:          877 2985 A

MONUMENTATION:           Bench Mark disk                       VM#:        20700
AGENCY:                  Division of Nearshore Research (DNR)  IDB PID:         
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   28° 46.3' N (  28.77167)          LONGITUDE:  95° 37.0' W ( -95.61739)


The bench mark is a brass disk set flush in the concrete sidewalk of the USACE.
The bench mark is located 23.24 m (76.2 ft) ENE of the centerline of the road,
16.68 m (54.7 ft) WNW of a light pole, and 14.04 m (46.1 ft) SE from the power
pole closest to the USACE parking lot.



                         BENCH MARK STAMPING:  2985 F 2019
                         DESIGNATION:          877 2985 F

MONUMENTATION:           Flange-encased Rod                    VM#:        23048
AGENCY:                  Conrad Blucher Institute              IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: BBGW74
LATITUDE:   28° 46.4' N (  28.77283)          LONGITUDE:  95° 37.1' W ( -95.61858)


The bench mark is located 52.00 m (170.6 ft) WNW of the northwest corner of a
concrete access hatch on the north side of FM 457, 31 m (101.7 ft) SSE of the
base of a draw bridge flashing light sign, 7.30 m (24.00 ft) WSW of the
centerline of FM 457 and 0.30 m (1.00 ft) from a witness post. The bench mark is
a stainless steel rod driven 20.70 m (67.90 ft) into the ground encased in a 6
in PVC pipe with concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8772985                         PUBLICATION DATE:  12/30/2020
Name:       SARGENT, ICWW                                     
            TX
NOAA Chart: 11319                           Latitude:   28° 46.3' N (  28.77142)
USGS Quad:  CEDAR LAKES WEST                Longitude:  95° 37.0' W ( -95.61717)


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


                         BENCH MARK STAMPING:  2985 G 2019
                         DESIGNATION:          877 2985 G

MONUMENTATION:           Flange-encased Rod                    VM#:        23049
AGENCY:                  Conrad Blucher Institute              IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   28° 46.4' N (  28.77403)          LONGITUDE:  95° 37.2' W ( -95.61939)


The bench mark is located 25.63 m (84.10 ft) NNW of a truck weight limit sign,
7.52 m (24.7 ft) WSW of the centerline of FM 457, 6.07 M (19.9 ft) N of a
concrete culvert below a caliche roadway and 0.3 m (1.0 ft) from an orange
witness post. The bench mark is a stainless steel rod driven 20.7 m (67.9 ft)
encased in a 6 in PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  2985 H 2020
                         DESIGNATION:          877 2985 H

MONUMENTATION:           Flange-encased Rod                    VM#:        23472
AGENCY:                  Conrad Blucher Institute (CBI)        IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   28° 46.5' N (  28.77492)          LONGITUDE:  95° 37.2' W ( -95.61972)


The bench mark is a stainless steel rod located 22.3 m (73.2 ft) NNW of NW side
of drainage culvert, 8.46 m (27.8 ft) NE of the centerline of FM 457, 3.2 m
(10.5 ft) NNW of CR 210 sign and 0.8 m (2.6 ft) SSW of a witness post. The
benchmark is driven 23.2 m (76.1 ft) into the ground encased in a 6 inch (15 cm)
PVC pipe with concrete kick block.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8772985                         PUBLICATION DATE:  12/30/2020
Name:       SARGENT, ICWW                                     
            TX
NOAA Chart: 11319                           Latitude:   28° 46.3' N (  28.77142)
USGS Quad:  CEDAR LAKES WEST                Longitude:  95° 37.0' W ( -95.61717)


                            T I D A L   D A T U M S 


Tidal datums at SARGENT, ICWW based on:

     LENGTH OF SERIES:      4 YEARS
     TIME PERIOD:           January 2016 - December 2019
     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 (09/21/2020)         =  1.223
     MEAN HIGHER HIGH WATER                     MHHW   =  0.209
     MEAN HIGH WATER                            MHW    =  0.198
     MEAN SEA LEVEL                             MSL    =  0.119
     MEAN TIDE LEVEL                            MTL    =  0.106
     MEAN LOW WATER                             MLW    =  0.013
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.111
     LOWEST  OBSERVED WATER LEVEL (01/04/2018)         = -0.482

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     2985 E 2012                                 0.709    0.511
     2985 A 2012                                 1.495    1.297
     2985 F 2019                                 0.553    0.355
     2985 G 2019                                 1.002    0.804
     2985 H 2020                                 0.418    0.220


Foot Notes:

Bench mark '2985 H 2020' is based on one differential leveling connection and
does not meet the quality control standards of the NOS. Therefore, caution
should be used when deriving elevations for this mark.

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

                                                                                
Station ID: 8772985                         PUBLICATION DATE:  12/30/2020
Name:       SARGENT, ICWW                                     
            TX
NOAA Chart: 11319                           Latitude:   28° 46.3' N (  28.77142)
USGS Quad:  CEDAR LAKES WEST                Longitude:  95° 37.0' W ( -95.61717)


                             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.