Superseded Bench Mark Sheet for 8729943, HURST HAMMOCK, PERDIDO RIVER FL

Present Epoch

Printable version

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

                                                   PUBLICATION DATE:  06/12/1984
Station ID: 8729943                                SUPERCEDED DATE:   04/21/2003
Name:       HURST HAMMOCK, PERDIDO RIVER                      
            FLORIDA
NOAA Chart: 11382                                  Latitude:         30° 27.5' N
USGS Quad:  LILLIAN                                Longitude:        87° 24.5' W


To reach the tidal bench marks from the intersection of U.S. Highway 90 and
Beaulah Road, proceed south on Beaulah Road for 2.4 miles (3.9 km) to a fork in
the road, follow right fork (Hurst Hammock Road) for 3.1 miles (5.0 km) south to
the roads end, continue east on the dirt road at the end of Hurst Hammock Road
for 560 feet (171 m) to a fenced property on the Perdido River.  The bench marks
are located along Hurst Hammock Road and the dirt road and the tide gage and
staff were located on a dock behind the private residence.


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


                 PRIMARY BENCH MARK STAMPING:  9943 A 1977

MONUMENTATION:           Survey Disk                               VM#:    10312
AGENCY:                                                            PID#:  BG4597
SETTING CLASSIFICATION:  Galvanized Steel Rod


The bench mark is 300 feet (91 m) east of Bench Mark 9943 B 1977, 19.8 feet (6.0
m) south of the dirt road that continues from the end of Hurst Hammock Road,
13.9 feet (4.2 m) east of the centerline of dirt drive leading to the private
residence, and 3.7 feet (1.1 m) east of the NE corner of the fence that
surrounds the property.  The bench mark is 0.4 foot (0.1 m) below ground level,
crimped to a galvanized steel rod driven 40 feet (12 m) and encased in a PVC
pipe and concrete kickblock.



                         BENCH MARK STAMPING:  9943 B 1977

MONUMENTATION:           Survey Disk                               VM#:    10313
AGENCY:                                                            PID#:  BG4596
SETTING CLASSIFICATION:  Galvanized Steel Rod


The bench mark is 300 feet (91 m) west of Bench Mark 9943 A 1977, 263 feet (80
m) east of Bench Mark 9943 C 1977, 14.8 feet (4.5 m) south of the dirt road at
the end of Hurst Hammock Road, 5.4 feet (1.6 m) NE of the NW corner of the fence
which surrounds the private property and 2.9 feet (0.9 m) east of a power pole
with a witness sign.  The bench mark is 0.4 foot (0.1 m) below ground level,
cirmped to a galvanized steel rod driven 40 feet (12 m), and encased in a PVC
pipe and concrete kickblock.

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

                                                   PUBLICATION DATE:  06/12/1984
Station ID: 8729943                                SUPERCEDED DATE:   04/21/2003
Name:       HURST HAMMOCK, PERDIDO RIVER                      
            FLORIDA
NOAA Chart: 11382                                  Latitude:         30° 27.5' N
USGS Quad:  LILLIAN                                Longitude:        87° 24.5' W


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


                         BENCH MARK STAMPING:  9943 C 1977

MONUMENTATION:           Survey Disk                               VM#:    10314
AGENCY:                                                            PID#:  BG4595
SETTING CLASSIFICATION:  Galvanized Steel Rod


The bench mark is 262 feet (80 m) SE of Bench Mark 9943 D 1977, 24.4 feet (7.4
m) west of the point of the intersection of Hurst Hammock Road and the dirt road
at the end of Hurst Hammock Road, and 5.1 feet (1.6 m) north of power pole
#0834054257 with a witness sign.  The bench mark is 0.3 foot (0.1 m) below
ground level, crimped to a galvanized steel rod driven 40 feet (12 m), and
encased in a PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  9943 D 1977

MONUMENTATION:           Survey Disk                               VM#:    10315
AGENCY:                                                            PID#:  BG4594
SETTING CLASSIFICATION:  Galvanized Steel Rod


The bench mark is 46.5 feet (14.2 m) SSE of the SE corner of the last residence
on the west side of Hurst Hammock Road, 35 feet (11 m) north of the north bank
of a tidal creek, 32 feet (10 m) west of the centerline of Hurst Hammock Road,
and 3.6 feet (1.1 m) south of lighted power pole #833654277 with a witness sign.
 The bench mark is level with the ground, crimped to a galvanized steel rod
driven 40 feet (12 m), and encased in a PVC pipe and concrete kickblock.

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

                                                   PUBLICATION DATE:  06/12/1984
Station ID: 8729943                                SUPERCEDED DATE:   04/21/2003
Name:       HURST HAMMOCK, PERDIDO RIVER                      
            FLORIDA
NOAA Chart: 11382                                  Latitude:         30° 27.5' N
USGS Quad:  LILLIAN                                Longitude:        87° 24.5' W


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


                         BENCH MARK STAMPING:  9943 E 1977

MONUMENTATION:           Survey Disk                               VM#:    10316
AGENCY:                                                            PID#:  BG4593
SETTING CLASSIFICATION:  Galvanized Steel Rod


The bench mark is 380 feet (116 m) north of Bench Mark 9943 D 1977, 46.9 feet
(14.3 m) east of the SE corner of a fenced residence, 28.6 feet (8.7 m) west of
the centerline of Hurst Hammock Road, and 8.6 feet (2.6 m) north of a lighted
power pole with a witness sign.  The bench mark is 0.3 foot (0.1 m) below ground
level, crimped to a galvanized steel rod driven 40 feet (12 m), and encased in a
PVC pipe and concrete kickblock.

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

                                                   PUBLICATION DATE:  06/12/1984
Station ID: 8729943                                SUPERCEDED DATE:   04/21/2003
Name:       HURST HAMMOCK, PERDIDO RIVER                      
            FLORIDA
NOAA Chart: 11382                                  Latitude:         30° 27.5' N
USGS Quad:  LILLIAN                                Longitude:        87° 24.5' W


                            T I D A L   D A T U M S 


Tidal datums at HURST HAMMOCK, PERDIDO RIVER based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           JULY 1977
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  8729962 PERDIDO BAY


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

     HIGHEST OBSERVED WATER LEVEL (04/22/1977)         =   1.91
     MEAN HIGHER HIGH WATER                     MHHW   =   0.78
     MEAN HIGH WATER                            MHW    =   0.76
     MEAN TIDE LEVEL                            MTL    =   0.41
     MEAN LOW WATER                             MLW    =   0.06
     MEAN LOWER LOW WATER                       MLLW   =   0.00
     LOWEST  OBSERVED WATER LEVEL (03/23/1977)         =  -0.93

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In FEET above:

     Stamping or Designation                    MLLW        MHW

     9943 A 1977                                 4.39      3.63
     9943 B 1977                                 8.26      7.50
     9943 C 1977                                11.27     10.51
     9943 D 1977                                 3.33      2.57
     9943 E 1977                                 3.73      2.97


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

                                                   PUBLICATION DATE:  06/12/1984
Station ID: 8729943                                SUPERCEDED DATE:   04/21/2003
Name:       HURST HAMMOCK, PERDIDO RIVER                      
            FLORIDA
NOAA Chart: 11382                                  Latitude:         30° 27.5' N
USGS Quad:  LILLIAN                                Longitude:        87° 24.5' 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 8729943 HURST HAMMOCK, PERDIDO RIVER, FL