NOAA Web Site Link Tides and Currents Home Page Transparent placeholder image

Bench Mark Sheet for 8678124, Raccoon Key Spit GA

Superseded Epoch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Small blue map location marker Unpublished bench mark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  5

                                                                                
Station ID: 8678124                         PUBLICATION DATE:  07/11/2012
Name:       RACCOON KEY SPIT                                  
            GA
NOAA Chart: 11504                           Latitude:   31°  0.9' N (  31.01481)
USGS Quad:  JEKYLL ISLAND                   Longitude:  81° 27.4' W ( -81.45597)


From I95 through Georgia take exit 29 for US-17/US-82/GA-520 toward
Brunswick/Waycross/S Georgia Pkwy for .48 km (0.3mi).  Keep right at the fork,
follow signs for US-17 and merge onto GA-25 N/GA-520 E/U.S. 17B N for 8.69 km
(5.4mi).  Slight right onto GA-520 E/Jekyll Island Rd Continue to follow GA-520
E for 10.29km (6.4mi).  Turn right onto S Riverview Dr for .96 km (0.6mi).  Turn
right on dirt road and follow around pond until you reach boat ramp.  Proceed by
boat southwest on ICW for 4.26 km (2.64 mi) to a southerly cut, proceed south on
cut for 0.34 km (0.21 mi) to NOAA/NOS Tide Station 867 8124.  The station is
mounted to unmarked pylon and bench marks are onshore west of station.


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


                 PRIMARY BENCH MARK STAMPING:  867 8124 A
                         DESIGNATION:          867 8124 A

MONUMENTATION:           Bench Mark disk                       VM#:        20371
AGENCY:                  NOS                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID#: BBCR11
LATITUDE:   31°  0.9' N (  31.01489)          LONGITUDE:  81° 27.4' W ( -81.45642)


The primary bench mark is a flange-encased metal rod located 20.2 km (12.6 mi)
NE of Harrietts Bluff, 15.3 km (9.5 mi) south-southeast of Brunswick, 6.8 km
(4.2 mi) east of dover bluff, 61.4 m (201.4 ft) NNW of bench mark 867 8124 B,
47.8 m (156.8 ft) W of NOAA/NOS tide station 867 8124, 29.3 m (96.1 ft)
north-northeast of the northeastern edge of the woods, 0.6 m (2.0 ft) east of a
witness post.  The bench mark is set 0.3 m (1.0 ft) above the ground.  The datum
point is set 0.3 m (1.0 ft) above the ground, being the top of a stainless steel
rod driven 11.0 m (36.1 ft) to refusal, and encased in a 5-inch logo cap.  

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

                                                                                
Station ID: 8678124                         PUBLICATION DATE:  07/11/2012
Name:       RACCOON KEY SPIT                                  
            GA
NOAA Chart: 11504                           Latitude:   31°  0.9' N (  31.01481)
USGS Quad:  JEKYLL ISLAND                   Longitude:  81° 27.4' W ( -81.45597)


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


                         BENCH MARK STAMPING:  867 8124 B
                         DESIGNATION:          867 8124 B

MONUMENTATION:           Bench Mark disk                       VM#:        20372
AGENCY:                  NOS                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   31°  0.9' N (  31.01436)          LONGITUDE:  81° 27.4' W ( -81.45617)


The bench mark is a flange-encased metal rod located 20.2 km (12.6 mi) NE of
Harrietts Bluff, 15.4 km (9.6 mi) SSE of Brunswick, 6.8 km (4.2 mi) east of
Dover Bluff, 64.0 m (210.0 ft) NNW of bench mark 867 8124 C, 61.4 m (201.4 ft)
SSE of bench mark 867 8124 A, 54.7 m (179.5 ft) SW of NOAA/NOS tide station 867
8124, 12.6 m (41.3 ft) NNE of the eastern edge of the woods, 0.6 m (2.0 ft) east
of a witness post.  The bench mark is set 15 cm (0.5 ft) above the ground, being
the top of a stainless steel rod driven 11.0 m (36.1 ft) to refusal, and encased
in a 5-inch logo cap.  



                         BENCH MARK STAMPING:  867 8124 C
                         DESIGNATION:          867 8124 C

MONUMENTATION:           Bench Mark disk                       VM#:        20373
AGENCY:                  NOS                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   31°  0.8' N (  31.01383)          LONGITUDE:  81° 27.4' W ( -81.45594)


The bench mark is a flange-encased metal rod located 20.1 km (12.5 mi) NE of
Harrietts Bluff, 15.5 km (9.6 mi) SSE of Brunswick, 6.8 km (4.2 mi) east of
Dover Bluff, 92.70 m (304.13 ft) SW of NOAA/NOS tide station 867 8124, 64.0 m
(210.0 ft) SSE of bench mark 867 8124 B, 62.3 m (204.4 ft) NNW of bench mark 867
8124 D, 11.9 m (39.0 ft) ENE of the eastern edge of the woods, 0.6 m (2.0 ft) E
of a witness post. The bench mark is set 15.0 cm (0.5 ft) above the ground,
being the top of a stainless steel rod driven 11.0 m (36.1 ft) to refusal, and
encased in a 5-inch logo cap.  

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

                                                                                
Station ID: 8678124                         PUBLICATION DATE:  07/11/2012
Name:       RACCOON KEY SPIT                                  
            GA
NOAA Chart: 11504                           Latitude:   31°  0.9' N (  31.01481)
USGS Quad:  JEKYLL ISLAND                   Longitude:  81° 27.4' W ( -81.45597)


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


                         BENCH MARK STAMPING:  867 8124 D
                         DESIGNATION:          867 8124 D

MONUMENTATION:           Bench Mark disk                       VM#:        20374
AGENCY:                  NOS                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   31°  0.8' N (  31.01331)          LONGITUDE:  81° 27.3' W ( -81.45569)


The bench mark is a flange-encased metal rod located 20.1 km (12.5 mi) NE of
Harrietts Bluff, 15.5 km (9.6 mi) SSE of Brunswick, 6.8 km (4.2 mi) east of
Dover Bluff, 92.70 m (304.13 ft) SW of NOAA/NOS tide station 867 8124, 64.0 m
(210.0 ft) SSE of bench mark 867 8124 B, 62.3 m (204.4 ft) NNW of bench mark 867
8124 D, 11.9 m (39.0 ft) ENE of the eastern edge of the woods, 0.6 m (2.0 ft) E
of a witness post. The bench mark is set 15.0 cm (0.5 ft) above the ground,
being the top of a stainless steel rod driven 11.0 m (36.1 ft) to refusal, and
encased in a 5-inch logo cap.  



                         BENCH MARK STAMPING:  867 8124 E
                         DESIGNATION:          867 8124 E

MONUMENTATION:           Bench Mark disk                       VM#:        20375
AGENCY:                  NOS                                   IDB PID#:        
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   31°  0.8' N (  31.01264)          LONGITUDE:  81° 27.3' W ( -81.45544)


The bench mark is a flange-encased metal rod located 20.0 km (12.4 mi) NE of
Harrietts Bluff, 15.6 km (9.7 mi) SSE of Brunswick, 6.9 km (4.3 mi) E of Dover
Bluff, 222.90 m (731.28 ft) SW of NOAA/NOS tide station 867 8124, 77.5 m (254.3
ft) SSW of bench mark 867 8124 D, 22.8 m (74.8 ft) NW of the edge of the
highwater shoreline, 13.5 m (44.3 ft) ENE of the eastern edge of the woods, 0.6
m (2.0 ft) east of a witness post.  The bench mark is set 15.0 cm (0.5 ft) above
the ground, being the top of a stainless steel rod driven 11.0 m (36.1 ft) to
refusal, and encased in a 5-inch logo cap.  

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

                                                                                
Station ID: 8678124                         PUBLICATION DATE:  07/11/2012
Name:       RACCOON KEY SPIT                                  
            GA
NOAA Chart: 11504                           Latitude:   31°  0.9' N (  31.01481)
USGS Quad:  JEKYLL ISLAND                   Longitude:  81° 27.4' W ( -81.45597)


                            T I D A L   D A T U M S 


Tidal datums at RACCOON KEY SPIT based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           February 2012 - April 2012
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8720030 FERNANDINA BEACH, AMELIA RIVER


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

     MEAN HIGHER HIGH WATER                     MHHW   =  2.172
     MEAN HIGH WATER                            MHW    =  2.063
     MEAN SEA LEVEL                             MSL    =  1.084
     MEAN TIDE LEVEL                            MTL    =  1.063
     MEAN LOW WATER                             MLW    =  0.063
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     867 8124 A                                  2.478    0.415
     867 8124 B                                  2.547    0.484
     867 8124 C                                  2.553    0.490
     867 8124 D                                  2.413    0.350
     867 8124 E                                  2.316    0.253


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

                                                                                
Station ID: 8678124                         PUBLICATION DATE:  07/11/2012
Name:       RACCOON KEY SPIT                                  
            GA
NOAA Chart: 11504                           Latitude:   31°  0.9' N (  31.01481)
USGS Quad:  JEKYLL ISLAND                   Longitude:  81° 27.4' W ( -81.45597)


                             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.

Return to Top
Products available at 8678124 Raccoon Key Spit, GA

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services