U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 1 of 5
Station ID: 8664442 PUBLICATION DATE: 03/10/1989
Name: MOORES LANDING, SEWEE BAY
SOUTH CAROLINA
NOAA Chart: 11531 Latitude: 32ø 56.2' N
USGS Quad: SEWEE BAY Longitude: 79ø 39.3' W
To reach the tidal bench marks from the intersection of U.S. Highway 17 (Ocean
Highway) and Sewee Road in Awendaw, proceed ESE for 3.35 miles (5.39 km) to a
Y, turn right and continue east for 1.35 miles (2.17 km) to Moores Landing.
The bench marks are near the Cape Romain Wildlife Refuge headquarters and at
the northern edge of the woods between the concrete dock and a wooden dock to
the NE. The tide gage and staff were at the end of the concrete dock inside a
U shaped section.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 5 1974
MONUMENTATION: Survey Disk VM#: 4040
AGENCY: PID#: CJ0255
SETTING CLASSIFICATION: Concrete Curb
The bench mark is set in a curb at the shore end of the concrete dock on the
wildlife refuge grounds, 6 feet (2 m) NE of the centerline of the dock, and 0.9
foot (0.3 m) above the dock floor.
BENCH MARK STAMPING: 1 1935
MONUMENTATION: Survey Disk VM#: 4036
AGENCY: PID#: CJ0257
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument about 0.3 mile (0.5 km) NE of Cape
Romain National Wildlife Refuge Headquarters, 0.1 mile (0.2 km) south of an old
2-story white farm house, 488 feet (149 m) SW of the shore end of L.C. Whites
wooden dock, 21 feet (6 m) SE of the edge of the woods and brush, 1.3 feet (0.4
m) north of a metal witness post with sign, and 0.2 foot (0.1 m) above ground
level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8664442 PUBLICATION DATE: 03/10/1989
Name: MOORES LANDING, SEWEE BAY
SOUTH CAROLINA
NOAA Chart: 11531 Latitude: 32ø 56.2' N
USGS Quad: SEWEE BAY Longitude: 79ø 39.3' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2 1935
MONUMENTATION: Survey Disk VM#: 4037
AGENCY: PID#: CJ0258
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument about 0.3 mile (0.5 km) NE of the
wildlife refuge headquarters, 304 feet (93 m) SW of the shore end of L.C.
Whites wooden dock, 182 feet (55 m) NE of Bench Mark 1 1935, 16.5 feet (5.0 m)
SE of the edge of the woods and brush, 14 feet (4 m) north of a 1.5-foot
(0.5 m) diameter pine tree, 1.2 feet (0.4 m) north of a metal witness post with
sign, and 0.3 foot (0.1 m) above ground level.
BENCH MARK STAMPING: 3 1935
MONUMENTATION: Survey Disk VM#: 4038
AGENCY: PID#: CJ0256
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument about 0.2 mile (0.3 km) NE of the
wildlife refuge headquarters, 628 feet (191 m) SW of the shore end of L.C.
Whites wooden dock, 140 feet (43 m) SW of Bench Mark 1 1935, 42 feet (13 m) SE
of the edge of the woods and brush, 37 feet (11 m) SE of a 1-foot (0.3 m)
diameter oak tree, and 1.3 feet (0.4 m) north of a metal witness post with
sign.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8664442 PUBLICATION DATE: 03/10/1989
Name: MOORES LANDING, SEWEE BAY
SOUTH CAROLINA
NOAA Chart: 11531 Latitude: 32ø 56.2' N
USGS Quad: SEWEE BAY Longitude: 79ø 39.3' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 4 1974
MONUMENTATION: Survey Disk VM#: 4039
AGENCY: PID#: CJ0254
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set in a concrete monument on the wildlife refuge grounds,
194.3 feet (59.2 m) NW of Bench Mark 5 1974, 73.4 feet (22.4 m) east of the NE
corner of a garage, 38.4 feet (11.7 m) south of a utility pole, and 1.9 feet
(0.6 m) east of a flagpole.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8664442 PUBLICATION DATE: 03/10/1989
Name: MOORES LANDING, SEWEE BAY
SOUTH CAROLINA
NOAA Chart: 11531 Latitude: 32ø 56.2' N
USGS Quad: SEWEE BAY Longitude: 79ø 39.3' W
T I D A L D A T U M S
Tidal datums at MOORES LANDING, SEWEE BAY based on:
LENGTH OF SERIES: 5 MONTHS
TIME PERIOD: MAY - SEPTEMBER 1976
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8665530 CHARLESTON
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (10/05/1975) = 7.42
MEAN HIGHER HIGH WATER (MHHW) = 5.60
MEAN HIGH WATER (MHW) = 5.23
MEAN TIDE LEVEL (MTL) = 2.71
MEAN LOW WATER (MLW) = 0.19
MEAN LOWER LOW WATER (MLLW) = 0.00
LOWEST OBSERVED WATER LEVEL (01/01/1976) = -1.58
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 5 1974 9.78 4.55
1 1935 11.09 5.86
2 1935 10.18 4.95
3 1935 11.66 6.43
NO 4 1974 10.71 5.48
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8664442 PUBLICATION DATE: 03/10/1989
Name: MOORES LANDING, SEWEE BAY
SOUTH CAROLINA
NOAA Chart: 11531 Latitude: 32ø 56.2' N
USGS Quad: SEWEE BAY Longitude: 79ø 39.3' 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 (NAVD 88).
NGVD 29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD 29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD 29 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 NGVD 29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD 88 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. NAVD 88 replaces NGVD 29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD 88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD 29 and NAVD 88 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 NAVD 88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD 88 elevations.
The NAVD 88 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, NAVD 88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD 88 elevations listed for
each bench mark in the NGS database.