U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 05/07/1986
Station ID: 8669601 SUPERCEDED DATE: 04/21/2003
Name: PINE ISLAND, RAMSHORN CREEK
SOUTH CAROLINA
NOAA Chart: 11512 Latitude: 32° 7.3' N
USGS Quad: FORT PULASKI Longitude: 80° 53.9' W
To reach the tidal bench marks by boat from the ramp at Harbour Town, Hilton
Head Island, proceed NW across Calibogue Sound to Cooper River, then SW on
Cooper River for 3.7 miles (6.0 km) to Ramshorn Creek, and south on Ramshorn
Creek for 0.8 mile (1.3 km) to Pine Island. The bench marks are located on Pine
Island. The tide gage and staff were located on an offshore platform on the
west side of the creek. Note: Care should be taken to anchor the boat offshore
of the clay bank, which is exposed at low water. The wake from a passing vessel
can literally lift a small craft onto these banks, causing it to become
stranded.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9601 D 1980
MONUMENTATION: Survey Disk VM#: 4673
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is 29.4 feet (9.0 m) north of a palmetto tree on the bluff edge,
20.6 feet (6.3 m) WNW of a 1.5-foot (0.5 m) diameter pine tree, 19.6 feet (6.0
m) ESE of a double oak tree, 7.9 feet (2.4 m) ESE of a witness post, and 3.0
feet (0.9 m) south of a witness post. The bench mark is crimped to a stainless
steel rod driven 40 feet (12 m) to refusal, encased in a 4-inch PVC pipe and
concrete kickblock, and 0.2 foot (0.1 m) below ground level.
BENCH MARK STAMPING: 9601 A 1980
MONUMENTATION: Survey Disk VM#: 4672
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is 59.0 feet (18.0 m) SE of a cluster of five oak trees, 29.0
feet (8.8 m) NE of a 2.0-foot (0.6 m) diameter oak tree, 16.8 feet (5.1 m) WNW
of the bluff edge, and 1.8 feet (0.5 m) SE of a witness post. The bench mark is
crimped to a stainless steel rod driven 40 feet (12 m) to refusal, encased in a
4-inch PVC pipe and concrete kickblock, and 0.2 foot (0.1 m) below ground level.
The PVC pipe extends 0.5 foot (0.2 m) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 05/07/1986
Station ID: 8669601 SUPERCEDED DATE: 04/21/2003
Name: PINE ISLAND, RAMSHORN CREEK
SOUTH CAROLINA
NOAA Chart: 11512 Latitude: 32° 7.3' N
USGS Quad: FORT PULASKI Longitude: 80° 53.9' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9601 F 1981
MONUMENTATION: Survey Disk VM#: 4674
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is 224.0 feet (68.3 m) ENE of Bench Mark 9601 G 1981, 140.5 feet
(42.8 m) WSW of Bench Mark 9601 A 1980, 11.1 feet (3.4 m) south of 1.0-foot (0.3
m) diameter oak tree, 1.7 feet (0.5 m) NE of a metal witness post, and at ground
level.
BENCH MARK STAMPING: 9601 G 1981
MONUMENTATION: Survey Disk VM#: 4675
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is 172.7 feet (52.6 m) NE of Bench Mark 9601 H 1981, 10.2 feet
(3.1 m) SE of 1.8-foot (0.5 m) diameter forked trunk oak tree, 2.1 feet (0.6 m)
east of a metal witness post, and at ground level.
BENCH MARK STAMPING: 9601 H 1981
MONUMENTATION: Survey Disk VM#: 4676
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is 149.5 feet (45.6 m) NNE of Bench Mark 9601 D 1980, 45.0 feet
(13.7 m) ESE of 2.0-foot (0.6 m) diameter oak tree, 23.3 feet (7.1 m) WNW of a
2.0-foot (0.6 m) diameter loblolly pine tree, 3.9 feet (1.2 m) NE of a metal
witness post, and at ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 05/07/1986
Station ID: 8669601 SUPERCEDED DATE: 04/21/2003
Name: PINE ISLAND, RAMSHORN CREEK
SOUTH CAROLINA
NOAA Chart: 11512 Latitude: 32° 7.3' N
USGS Quad: FORT PULASKI Longitude: 80° 53.9' W
T I D A L D A T U M S
Tidal datums at PINE ISLAND, RAMSHORN CREEK based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: SEPTEMBER-NOVEMBER 1981
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8670870 FORT PULASKI, GA
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (11/13/1981) = 10.29
MEAN HIGHER HIGH WATER MHHW = 7.70
MEAN HIGH WATER MHW = 7.33
MEAN TIDE LEVEL MTL = 3.77
MEAN LOW WATER MLW = 0.21
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (09/17/1981) = -0.76
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
9601 D 1980 9.55 2.22
9601 A 1980 11.57 4.24
9601 F 1981 11.46 4.13
9601 G 1981 11.56 4.23
9601 H 1981 11.15 3.82
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 05/07/1986
Station ID: 8669601 SUPERCEDED DATE: 04/21/2003
Name: PINE ISLAND, RAMSHORN CREEK
SOUTH CAROLINA
NOAA Chart: 11512 Latitude: 32° 7.3' N
USGS Quad: FORT PULASKI Longitude: 80° 53.9' 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.