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Bench Mark Sheet for 8728690, Apalachicola FL

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


To reach the tidal bench marks from the Post Office at the corner of Commerce
and D Streets in Apalachicola, proceed north along D Street one block to Water
Street, then NW along Water Street for 0.32 km (0.2 mi) to the U.S. Coast Guard
Light Attendant Station.  The bench marks are located throughout the city.  The
tide gage and staff are located at the east corner of the Coast Guard dock.


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


                 PRIMARY BENCH MARK STAMPING:  14.124 NO 1 1933
                         DESIGNATION:          872 8690 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:          767
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AS0240
SETTING CLASSIFICATION:  Step                                  OPUS PID:        
LATITUDE:   29° 43.6' N (  29.72739)          LONGITUDE:  84° 59.0' W ( -84.98331)


The primary bench mark is a disk set flush in a concrete bannister on the NE
corner of the steps at the main entrance to the Post Office, 17.68 m (58.01 ft)
SE of the centerline of D Street, 14.33 m (47.01 ft) SW of the centerline of
Commerce Street, 2.96 m (9.71 ft) SW of a flagpole, and 0.79 m (2.59 ft) above
ground level.  Note:  The bench mark may be covered by a potted plant in a box.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  APALACHICOLA 1934 15.771
                         DESIGNATION:          APALACHICOLA

MONUMENTATION:           Tidal Station disk                    VM#:          768
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AS0244
SETTING CLASSIFICATION:  Concrete Base                         OPUS PID#: AS0244
LATITUDE:   29° 43.5' N (  29.72556)          LONGITUDE:  84° 59.1' W ( -84.98581)


The bench mark is a disk set in the top of the south corner of the second step
above ground of the concrete base of Gorrie Monument, in the north angle of the
intersection of 6th Street and D Street, 30.90 m (101.38 ft) ENE ofthe
centerline of 6th Street, 29.65 m (97.28 ft) WNW of the center of D Street,
25.25 m (82.84 ft) SE of the east corner of the Trinity Episcopal Church, and
0.38 m (1.25 ft) above the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  J 45 1934 15.449
                         DESIGNATION:          J 45

MONUMENTATION:           Tidal Station disk                    VM#:          769
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AS0241
SETTING CLASSIFICATION:  Step                                  OPUS PID#: AS0241
LATITUDE:   29° 43.5' N (  29.72567)          LONGITUDE:  84° 59.0' W ( -84.98331)


The bench mark is a disk set in top of the center of the third step from bottom
of base of Marks Monument and on the SE side of the monument, in the SW angle of
the intersection, west and across the street from the courthouse, 19.64 m (64.44
ft) south of the centerline of C street, 15.10 m (49.54 ft) SW of the center of
U.S. Highway 98, and 0.85 m (2.79 ft) north of the south edge of the 3RD step of
the monument.



                         BENCH MARK STAMPING:  NO 3 1974
                         DESIGNATION:          872 8690 TIDAL 3

MONUMENTATION:           Bench Mark disk                       VM#:          771
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AS0514
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   29° 43.8' N (  29.72947)          LONGITUDE:  84° 59.1' W ( -84.98486)


The bench mark is a disk set flush in the concrete steps of the front entrance
to Wefings Marine Hardware, 47.2 m (154.9 ft) SW of bench mark NO 4 1974, 28.35
m (93.01 ft) WNW of utility pole 4/60/1/75, 16.10 m (52.82 ft) WNW of the
centerline of F Street, and 10.05 m (32.97 ft) SW of the centerline of Water
Street.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  NO 4 1974
                         DESIGNATION:          872 8690 TIDAL 4

MONUMENTATION:           Bench Mark disk                       VM#:          772
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AS0242
SETTING CLASSIFICATION:  Flagpole base                         OPUS PID:        
LATITUDE:   29° 43.8' N (  29.72967)          LONGITUDE:  84° 59.1' W ( -84.98450)


The bench mark is a disk set flush in the north corner of a 1.68 m x 1.68 m
(5.51ft x 5.51 ft) concrete flagpole base at the US Coast Guard light attendant
station, 32.50 m (106.63 ft) ENE of the centerline of Water Street, 11.62 m
(38.12 ft) WSW of the SW corner of the tide station, and 0.10 m (0.33 ft) above
the ground surface.



                         BENCH MARK STAMPING:  8690 A 1978
                         DESIGNATION:          872 8690 A TIDAL

MONUMENTATION:           Bench Mark disk                       VM#:          773
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72333)          LONGITUDE:  84° 59.0' W ( -84.98325)


The bench mark is a disk set at the SW corner of Battery Park between two large
live oak trees, 53.95 m (176.8 ft) SE of the centerline of Market Street, 51.8 m
(169.9 ft) NW of the west corner of the boat basin, 34.44 m (112.99 ft) NNE of
the centerline of Bay Avenue, 11.0 m (36.1ft) ENE of the centerline of 6th
Street, and 0.09 m (0.3 ft) south of a witness post.  The bench mark is crimped
to the top of a stainless steel rod driven 8.53 m (27.9 ft), and encased in a
5-inch PVC pipe and concrete kick-block with an aluminum access LTD.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  8690 B 1978
                         DESIGNATION:          872 8690 B

MONUMENTATION:           Bench Mark disk                       VM#:          774
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: DM4900
LATITUDE:   29° 43.3' N (  29.72164)          LONGITUDE:  84° 59.1' W ( -84.98425)


The bench mark is a disk located 4 m (13.1 ft) ESE of the center of the
intersection of Bay Avenue and 8th Street, 4 m (13.1 ft) WNW of Utility Pole
A51253, 2nd number 025257/107075), and 1.07 m (3.51 ft) SE of the south edge of
Bay Avenue.  The bench mark is crimped to a stainless steel rod driven 9.8 m
(32.2 ft), and encased in a 5-inch PVC pipe and concrete kickblock with aluminum
access LTD.



                         BENCH MARK STAMPING:  8690 D 1983
                         DESIGNATION:          872 8690 D TIDAL

MONUMENTATION:           Bench Mark disk                       VM#:          775
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Step                                  OPUS PID:        
LATITUDE:   29° 43.6' N (  29.72608)          LONGITUDE:  84° 58.9' W ( -84.98242)


The bench mark is a disk set flush in the NW corner of the bottom of the north
entrance to the Franklin County Courthouse, 57.15 m (187.50 ft) ENE of bench
mark J 45 1934 15.449, 33.00 m (108.27 ft) ESE of the centerline of Highway
98/Market Street, 18.59 m (60.99 ft) east of the courthouse flag pole, 17.25 m
(56.59 ft) south of the centerline of Leslie Street, and 2.59 m (8.50 ft) WSW of
the centerline of the north entrance sidewalk to the courthouse.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  8690 E 1983
                         DESIGNATION:          872 8690 E TIDAL

MONUMENTATION:           Bench Mark disk                       VM#:          776
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Driveway                              OPUS PID:        
LATITUDE:   29° 43.7' N (  29.72892)          LONGITUDE:  84° 59.1' W ( -84.98428)


The bench mark is a disk set flush in the concrete foundation lip of
Apalachicola Volunteer Fire Department, in front of the second column north of
the SE corner of the building, between two 1 m (3.28 ft) high and 0.09 m (0.30
ft) diameter steel pipes, 91.44 m (300.00 ft) SE of bench mark NO 3 1974, 75.29
m (247.01 ft) SE of the centerline of F Street, 49.38 m (162.01 ft) WSW of the
SW shoreline of Apalachicola River, 10.50 m (34.45 ft) WSW of the centerline of
Water Street, 4.63 m (15.19 ft) NW of the SE corner of the fire station, and
0.24 m (0.79 ft) NE of the NE face of the fire station.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  WEST POINT NO 2
                         DESIGNATION:          STA 3-66 WEST POINT NO 2

MONUMENTATION:           Tidal Station disk                    VM#:        17469
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AS0243
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72330)          LONGITUDE:  84° 59.0' W ( -84.98330)


The bench mark is a disk set in a concrete post, 39 m (128.0 ft) NW of the
centerline of B Avenue, 7 m (23.0 ft) SW of the centerline of 5 th Street, 8.99
m (29.49 ft) SE of the extended line of the SE end of a residence at NO. 28, 5
th street, 5 m (16.4 ft) east of a 30-inch oak tree, and  0.03 m (0.098 ft)
above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  P 294 1967
                         DESIGNATION:          P 294

MONUMENTATION:           Bench Mark disk                       VM#:        19078
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:  AS0138
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   29° 44.1' N (  29.73464)          LONGITUDE:  85°  1.1' W ( -85.01858)


The bench mark is a disk set in the top of a concrete post projecting 0.06 m
(0.2 ft) above the level of the ground, 11.13 m (36.5 ft) SW of the center line
of the highway, 8.53 m (28.0 ft) SE of a fence corner around a lot, 6.40 m (21.0
ft) NW of the center line of driveway, 0.40 m (1.3 ft) SE of a metal witness
post, 0.30 m (1.0 ft) NE of a fence line, and 0.30 m (1.0 ft) above the level of
the highway..

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  Q 294 1967
                         DESIGNATION:          Q 294

MONUMENTATION:           Bench Mark disk                       VM#:        19079
AGENCY:                  US Coast & Geodetic Survey
                         (USC&GS)                                 IDB PID#:  AS0143
SETTING CLASSIFICATION:  Concrete Monument                     OPUS PID:        
LATITUDE:   29° 43.9' N (  29.73144)          LONGITUDE:  85°  0.2' W ( -85.00339)


The bench mark is a disk set in the top of a concrete post projecting 0.06 m
(0.2 ft) above the level of the ground, 36.58 m (120.0 ft) NW of the center of
the junction of 24th Avenue, near the junction of the west one of 4 driveways
leading north into the Magnolia Cemetery, 9.75 m (32.0 ft) north of the center
line of the highway, 4.42 m (14.5 ft) west of the center line of driveway, 0.46
m (1.5 ft) east of a metal witness post, and about level with the highway.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 10 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


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


                         BENCH MARK STAMPING:  D 689 2007
                         DESIGNATION:          D 689

MONUMENTATION:           Survey disk                           VM#:        19080
AGENCY:                  Florida Dept. of Environmental
                         Protection (FLDEP)                    IDB PID#:  DM4901
SETTING CLASSIFICATION:  Concrete Culvert Head Wall            OPUS PID:        
LATITUDE:   29° 43.4' N (  29.72350)          LONGITUDE:  84° 59.6' W ( -84.99378)


The bench mark is a disk set flush in the top of the NE end of a concrete
culvert headwall in the SE quadrant of the intersection located about 83.82 m
(275.0 ft) SW of the centerline of 12th street, 11.70 m (38.4 ft) NE of the
centerline of 13th street, 9.02 m (29.6 ft) SE of the centerline of Avenue H,
0.30 m 0.30 m (1.0 ft) below the level of Avenue H and 0.5 ft NW of a carsonite
witness post.



                         BENCH MARK STAMPING:  8690 F 2009
                         DESIGNATION:          872 8690 F

MONUMENTATION:           Metal Rod                             VM#:        19558
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: DO1545
LATITUDE:   29° 43.5' N (  29.72439)          LONGITUDE:  84° 58.9' W ( -84.98083)


The bench mark is a metal rod set flush in a grassy area on the foot of the
Municipal commercial pier is set 120.9 m (396.7 ft) NE of the east side of the
public boat ramp, 55.8 m (183.1 ft) SE of the SE corner of the baseball field
concession stand, 35.0 m (114.8 ft) WSW of the SW corner of the tidal station,
24.7 m (81.0 ft) ESE of water ST., 2.0 m (6.6 ft) NE of the NE corner of the
city dock, and 1.0 m (3.28 ft) SE of a telephone pole.  The datum point is set
on top of a flange-encased rod, being the top of a stainless steel rod driven
27.3 m (89.57 ft) to refusal, and encased in a 5-inch NOS logo cap.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 11 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


                            T I D A L   D A T U M S 


Tidal datums at APALACHICOLA, APALACHICOLA RIVER based on:

     LENGTH OF SERIES:      19 YEARS
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (07/10/2005)         =  2.452
     MEAN HIGHER HIGH WATER                     MHHW   =  0.492
     MEAN HIGH WATER                            MHW    =  0.461
     MEAN TIDE LEVEL                            MTL    =  0.291
     MEAN SEA LEVEL                             MSL    =  0.277
     North American Vertical Datum              NAVD88 =  0.232
     MEAN LOW WATER                             MLW    =  0.122
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/18/1981)         = -0.560

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     14.124 NO 1 1933                            4.362    3.902
     APALACHICOLA 1934 15.771                    4.869    4.408
     J 45 1934 15.449                            4.769    4.309
     NO 3 1974                                   1.886    1.426
     NO 4 1974                                   1.004    0.543
     8690 A 1978                                 2.779    2.318
     8690 B 1978                                 1.642    1.182
     8690 D 1983                                 3.719    3.259
     8690 E 1983                                 1.886    1.425
     WEST POINT NO 2                             4.867    4.406
     P 294 1967                                  4.031    3.570
     Q 294 1967                                  5.398    4.937
     D 689 2007                                  4.789    4.329
     8690 F 2009                                 0.966    0.505


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 12 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


Foot Notes:

Bench marks D 689 2007, P 294 1967, Q 294 1967, and WEST POINT NO 2 are based on
one differential leveling connection and do not meet the quality control
standards of the NOS.  Therefore, caution should be used when deriving
elevations for these marks.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 13 of 13

                                                                                
Station ID: 8728690                         PUBLICATION DATE:  10/12/2011
Name:       APALACHICOLA, APALACHICOLA RIVER                  
            FL
NOAA Chart: 11401                           Latitude:   29° 43.6' N (  29.72670)
USGS Quad:  APALACHICOLA                    Longitude:  84° 58.9' W ( -84.98170)


                             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.

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Products available at 8728690 Apalachicola, FL

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services