U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)





                         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  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


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


                 PRIMARY BENCH MARK STAMPING:  0166 B 2010
                         DESIGNATION:          874 0166 B
                         ALIAS:                0166 B 2010

MONUMENTATION:           Metal Rod                             VM#:        19679
AGENCY:                  Conrad Blucher Institute              IDB PID#:  DO5987
SETTING CLASSIFICATION:  Metal rod driven into the ground      OPUS PID#: DO5987
LATITUDE:   30° 24.8' N (  30.41300)          LONGITUDE:  88° 24.2' W ( -88.40333)


The primary bench mark is a metal rod located 8.5 m (27.9 ft) north of center of
the main road, 44.2 m (145.0 ft) west of 874 0166 A, and 33.3 m (109.3 ft) west
of the north corner of ramp walkway to boat dock.  The stainless steel rod is
driven into the ground 92 ft (28.0 m) until refusal, encased in a 6" PVC pipe
that projects 10" from the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


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


                         BENCH MARK STAMPING:  0166 A 2010
                         DESIGNATION:          874 0166 A
                         ALIAS:                0166 A 2010

MONUMENTATION:           Bench Mark disk                       VM#:        19680
AGENCY:                  Conrad Blucher Institute              IDB PID#:  DO5988
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   30° 24.8' N (  30.41303)          LONGITUDE:  88° 24.2' W ( -88.40289)


The bench mark is a disk set into the corner of the concrete walkway located
8.52 m (27.95 ft) south of the entrance to the ramp walkway leading to tide
gauge, 20.4 m (66.9 ft) NE of the northern corner of the ramp leading to the
boat dock, and 44.2 m (145.0 ft) east of 847 0166 B.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


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


                         BENCH MARK STAMPING:  0166 C 2010
                         DESIGNATION:          874 0166 C
                         ALIAS:                0166 C 2010

MONUMENTATION:           Metal Rod                             VM#:        19681
AGENCY:                  Conrad Blucher Institute              IDB PID#:  DO5986
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   30° 24.8' N (  30.41300)          LONGITUDE:  88° 24.2' W ( -88.40406)


The bench mark is a metal rod located 6.3 m (20.7 ft) west of center of Cereal
LN, 7.4 m (24.28 ft) north of center of main paved road, and 11.7 m (38.4 ft)
north/NW of green cable route marker.  The metal rod is a stainless steel rod
driven 28.0 m (92 ft) until refusal.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


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


                         BENCH MARK STAMPING:  0166 D 2010
                         DESIGNATION:          874 0166 D
                         ALIAS:                0166 D 2010

MONUMENTATION:           Metal Rod                             VM#:        19682
AGENCY:                  Conrad Blucher Institute              IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   30° 24.9' N (  30.41436)          LONGITUDE:  88° 24.2' W ( -88.40403)


The bench mark is a metal rod located 5.8 m (19.0 ft) NW of center of Cereal LN,
14.8 m (48.6 ft) SW of telephone pole number 99N, and 77.8 m (255.2 ft) north of
cable route marker near driveway.  The metal rod is a stainless steel rod driven
28.0 m (92 ft) until refusal.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


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


                         BENCH MARK STAMPING:  0166 E 2010
                         DESIGNATION:          874 0166 E
                         ALIAS:                0166 E 2010

MONUMENTATION:           Metal Rod                             VM#:        19683
AGENCY:                  Conrad Blucher Institute              IDB PID#:  DO5985
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   30° 24.9' N (  30.41436)          LONGITUDE:  88° 24.2' W ( -88.40403)


The bench mark is a metal rod located 12.0 m (39.4 ft) south of the main paved
road, 12.0 m (39.4 ft) SE of cable route marker P63, and 0.3 m (1.0 ft) NE of
chain link fence.  The metal rod is a stainless steel rod driven 31.7 m (104 ft)
until refusal.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


                            T I D A L   D A T U M S 


Tidal datums at GRAND BAY NERR, MISSISSIPPI SOUND based on:

     LENGTH OF SERIES:      6 MONTHS
     TIME PERIOD:           March 2011 - August 2011
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8741533 PASCAGOULA NOAA LAB, PASCAGOULA RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.485
     MEAN HIGH WATER                            MHW    =  0.456
     MEAN TIDE LEVEL                            MTL    =  0.248
     MEAN SEA LEVEL                             MSL    =  0.236
     North American Vertical Datum              NAVD88 =  0.183
     MEAN LOW WATER                             MLW    =  0.039
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     0166 B 2010                                 0.703    0.247
     0166 A 2010                                 1.206    0.750
     0166 C 2010                                 1.156    0.700
     0166 D 2010                                 0.893    0.437
     0166 E 2010                                 0.838    0.382


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  8

                                                                                
Station ID: 8740166                         PUBLICATION DATE:  07/08/2013
Name:       GRAND BAY NERR, MISSISSIPPI SOUND                 
            MS
NOAA Chart: 11373                           Latitude:   30° 24.8' N (  30.41300)
USGS Quad:  Kreole                          Longitude:  88° 24.2' W ( -88.40272)


                             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.