U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 09/29/1989
Station ID: 8662670 SUPERCEDED DATE: 04/21/2003
Name: PLEASANT HILL LANDING, SANTEE RIVER
SOUTH CAROLINA
NOAA Chart: Latitude: 33° 14.7' N
USGS Quad: HONEY HILL Longitude: 79° 31.1' W
To reach the tidal bench marks from U.S. Highway 17 at McClellanville, proceed
north on U.S. Highway 17 for 5.9 miles (9.5 km) to State Road S-10-857, go west
on State Road S-10-857 for 3.2 miles (5.1 km) to the end of the paved road,
continue west on the dirt road for 1.5 miles (2.4 km), then turn left and go 0.1
mile (0.2 km) to the Elmwood Ranger Station entrance, turn right to the station
and continue past the station for 0.4 mile (0.6 km) to Echaw Road (Forest Route
204), turn right onto Echaw Road and go 5.8 miles (9.3 km) to the North Hampton
Hunt Unit gate, go through the gate, then turn right onto a clay bed road and go
0.9 mile (1.4 km) to a fork, bear right for 0.2 mile (0.3 km) to the South
Carolina Gas and Electric right-of-way with a pumping station to the left, and
continue past the clearing for 0.7 mile (1.1 km) to Pleasant Hill Landing.
NOTE: Access to this site after a moderate rain usually requires a 4-wheel
drive vehicle. The tidal bench marks are along the road leading to the landing.
The tide gage and staff were on a pier just west of the boat ramp.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 2670 A 1976
MONUMENTATION: Survey Disk VM#: 3938
AGENCY: PID:
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is set near the pier just west of the boat ramp, 61.0 feet (18.6
m) WNW of the centerline of a dirt path leading to the pier, 35.6 feet (10.9 m)
west of a 2.0-foot (0.6 m) diameter hickory tree, 31.2 feet (9.5 m) NE of a
1.0-foot (0.3 m) diameter pine tree, 16.0 feet (4.9 m) SSW of the edge of the
south bank of the river, and 14.7 feet (4.5 m) SW of a 1.5-foot (0.4 m) diameter
gum tree. The bench mark is crimped to a copper-clad steel rod driven 40 feet
(12 m) to refusal, and encased in a 4-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 09/29/1989
Station ID: 8662670 SUPERCEDED DATE: 04/21/2003
Name: PLEASANT HILL LANDING, SANTEE RIVER
SOUTH CAROLINA
NOAA Chart: Latitude: 33° 14.7' N
USGS Quad: HONEY HILL Longitude: 79° 31.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2670 G 1982
MONUMENTATION: Survey Disk VM#: 3939
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument along the west side of the road
leading to Pleasant Hill Landing, 244 feet (74 m) north of 2670 H 1982, 36.0
feet (11.0 m) WNW of the center of the rock paved parking area, 29.5 feet (9.0
m) east of a metal double trash receptacle, 18.0 feet (5.5 m) north of a
1.5-foot (0.5 m) diameter pine tree, 2.5 feet (0.8 m) WNW of the center of a
wooden guard rail, and 0.2 foot (0.1 m) above ground level.
BENCH MARK STAMPING: 2670 H 1982
MONUMENTATION: Survey Disk VM#: 3940
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument along the west side of the road
leading to Pleasant Hill Landing, 60.6 feet (18.5 m) SSE of a 1.3-foot (0.4 m)
diameter metal drain pipe, 27.5 feet (8.4 m) WSW of the centerline of the dirt
road, 5.9 feet (1.8 m) SSE of a 1.2-foot (0.4 m) diameter pine tree, 1.3 feet
(0.4 m) ENE of a metal witness post with sign, and 0.3 foot (0.1 m) below ground
level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 09/29/1989
Station ID: 8662670 SUPERCEDED DATE: 04/21/2003
Name: PLEASANT HILL LANDING, SANTEE RIVER
SOUTH CAROLINA
NOAA Chart: Latitude: 33° 14.7' N
USGS Quad: HONEY HILL Longitude: 79° 31.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2670 J 1982
MONUMENTATION: Survey Disk VM#: 3941
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument along the west side of the road
leading to Pleasant Hill Landing, 254.5 feet (77.6 m) north of 2670 K 1982, 22.7
feet (6.9 m) west of the centerline of the dirt road, 22.2 feet (6.8 m) south of
the 1.2-foot (0.4 m) diameter gum tree, 2.9 feet (0.9 m) NNW of a metal witness
post with sign, and 0.2 foot (0.1 m) above ground level.
BENCH MARK STAMPING: 2670 K 1982
MONUMENTATION: Survey Disk VM#: 3942
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument along the east side of the road
leading to Pleasant Hill Landing, 25.7 feet (7.8 m) ESE of the centerline of the
dirt road, 6.0 feet (1.8 m) SW of a 2.0-foot (0.6 m) diameter pine tree, 5.6
feet (1.7 m) NNE of a 1.2-foot (0.4 m) diameter pine tree, 1.3 feet (0.4 m) west
of a metal witness post with sign, and level with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 09/29/1989
Station ID: 8662670 SUPERCEDED DATE: 04/21/2003
Name: PLEASANT HILL LANDING, SANTEE RIVER
SOUTH CAROLINA
NOAA Chart: Latitude: 33° 14.7' N
USGS Quad: HONEY HILL Longitude: 79° 31.1' W
T I D A L D A T U M S
Tidal datums at PLEASANT HILL LANDING, SANTEE RIVER based on:
LENGTH OF SERIES: 8 MONTHS
TIME PERIOD: AUGUST 1976 - JULY 1977
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8662799 SOUTH SANTEE RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (12/24/1976) = 9.25
MEAN HIGHER HIGH WATER MHHW = 2.62
MEAN HIGH WATER MHW = 2.42
MEAN TIDE LEVEL MTL = 1.28
MEAN LOW WATER MLW = 0.14
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (02/25/1977) = -0.98
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
2670 A 1976 22.17 19.75
2670 G 1982 16.09 13.67
2670 H 1982 12.64 10.22
2670 J 1982 12.51 10.09
2670 K 1982 17.45 15.03
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 09/29/1989
Station ID: 8662670 SUPERCEDED DATE: 04/21/2003
Name: PLEASANT HILL LANDING, SANTEE RIVER
SOUTH CAROLINA
NOAA Chart: Latitude: 33° 14.7' N
USGS Quad: HONEY HILL Longitude: 79° 31.1' 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.