U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8669801 PUBLICATION DATE: 03/09/2004
Name: BLOODY POINT, NEW RIVER
SC
NOAA Chart: 11512 Latitude: 32° 4.9' N ( 32.08170)
USGS Quad: FORT PULASKI Longitude: 80° 52.7' W ( -80.87830)
To reach the tidal bench marks by boat from the public boat landing at South
Beach, Hilton Head Island, proceed north and west across Calibogue Sound to
Cooper River (the Intracoastal Waterway), then proceed SW on Copper River for
6.0 km (3.7 mi) to Ramshorn Creek, then proceed south on Ramshorn Creek for 1.9
km (1.2 mi) to New River, then proceed south on New River for 7.9 km (4.9 mi) to
the entrance. The bench marks are located on the west side of Bloody Point.
The tide gage and staff were located on an offshore platform off Bloody Point,
Daufuskie Island.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9801 E 1980
DESIGNATION: 866 9801 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 4693
AGENCY: National Ocean Survey (NOS) IDB PID#: CK2117
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 32° 4.9' N ( 32.08170) LONGITUDE: 80° 52.6' W ( -80.87670)
The primary bench mark is a disk located 4.02 m (13.2 ft) NNE of a 0.46 m (1.5
ft) diameter pine tree, 2 m (7 ft) SSE of a 0.46 m (1.5 ft) diameter pine tree,
1.62 m (5.3 ft) NNE of a 0.46 m (1.5 ft) diameter pine tree, and 0.61 m (2.0 ft)
west of a witness post. The bench mark is crimped to the top of a stainless
steel rod driven 10.7 m (35 ft) 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
Station ID: 8669801 PUBLICATION DATE: 03/09/2004
Name: BLOODY POINT, NEW RIVER
SC
NOAA Chart: 11512 Latitude: 32° 4.9' N ( 32.08170)
USGS Quad: FORT PULASKI Longitude: 80° 52.7' W ( -80.87830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9801 C 1980
DESIGNATION: 866 9801 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 4692
AGENCY: National Ocean Survey (NOS) IDB PID#: CK2116
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 32° 4.9' N ( 32.08170) LONGITUDE: 80° 52.6' W ( -80.87670)
The bench mark is a disk located 24.93 m (81.8 ft) SSW of bench mark 9801 E
1980, 16.61 m (54.5 ft) NNE of a triple-trunk oak tree, 8.35 m (27.4 ft) WNW of
a 0.37 m (1.2 ft) diameter twin oak tree, and 5.43 m (17.8 ft) ENE of a 0.24 m
(0.8 ft) diameter pine tree. The bench mark is set 9 cm (0.3 ft) below ground
level, crimped to the top of a stainless steel rod driven 12.2 m (40 ft) to
refusal, and encased in a 4-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 9801 F 1981
DESIGNATION: 866 9801 F TIDAL
MONUMENTATION: Tidal Station disk VM#: 4694
AGENCY: National Ocean Survey (NOS) IDB PID#: CK2118
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 32° 5.0' N ( 32.08330) LONGITUDE: 80° 52.6' W ( -80.87670)
The bench mark is a disk set in a concrete monument, 36.48 m (119.7 ft) SSW of
bench mark 9801 G 1981, 5.64 m (18.5 ft) SSW of a 0.46 m (1.5 ft) diameter oak
tree, 4.18 m (13.7 ft) ENE of a twin oak tree, and 1.40 m (4.6 ft) west of a
witness post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8669801 PUBLICATION DATE: 03/09/2004
Name: BLOODY POINT, NEW RIVER
SC
NOAA Chart: 11512 Latitude: 32° 4.9' N ( 32.08170)
USGS Quad: FORT PULASKI Longitude: 80° 52.7' W ( -80.87830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9801 G 1981
DESIGNATION: 866 9801 G TIDAL
MONUMENTATION: Tidal Station disk VM#: 4695
AGENCY: National Ocean Survey (NOS) IDB PID#: CK2119
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 32° 5.0' N ( 32.08330) LONGITUDE: 80° 52.6' W ( -80.87670)
The bench mark is a disk set in a concrete monument, 66.66 m (218.7 ft) WSW of
bench mark 9801 H 1981, 7.47 m (24.5 ft) south of a 0.76 m (2.5 ft) diameter oak
tree, 4.45 m (14.6 ft) north of a 0.49 m (1.6 ft) diameter oak tree, 0.91 m (3.0
ft) SW of a witness post, and 0.06 m (0.2 ft) above ground level.
BENCH MARK STAMPING: 9801 H 1981
DESIGNATION: 866 9801 H TIDAL
MONUMENTATION: Tidal Station disk VM#: 4696
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 32° 4.9' N ( 32.08170) LONGITUDE: 80° 52.6' W ( -80.87670)
The bench mark is a disk set in a concrete monument, 12.59 m (41.3 ft) WNW of a
1.22 m (4.0 ft) diameter five-trunk oak tree, 3.02 m (9.9 ft) SSE of a 0.40 m
(1.3 ft) diameter pine tree, 0.85 m (2.8 ft) west of a witness post, and 0.06 m
(0.2 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8669801 PUBLICATION DATE: 03/09/2004
Name: BLOODY POINT, NEW RIVER
SC
NOAA Chart: 11512 Latitude: 32° 4.9' N ( 32.08170)
USGS Quad: FORT PULASKI Longitude: 80° 52.7' W ( -80.87830)
T I D A L D A T U M S
Tidal datums at BLOODY POINT, NEW RIVER based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: May 1981 - July 1981
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8670870 FORT PULASKI, SAVANNAH RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 2.238
MEAN HIGH WATER MHW = 2.126
North American Vertical Datum NAVD88 = 1.240
MEAN SEA LEVEL MSL = 1.135
MEAN TIDE LEVEL MTL = 1.094
MEAN LOW WATER MLW = 0.062
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
9801 E 1980 3.115 0.989
9801 C 1980 2.692 0.566
9801 F 1981 4.389 2.263
9801 G 1981 3.222 1.096
9801 H 1981 3.451 1.325
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8669801 PUBLICATION DATE: 03/09/2004
Name: BLOODY POINT, NEW RIVER
SC
NOAA Chart: 11512 Latitude: 32° 4.9' N ( 32.08170)
USGS Quad: FORT PULASKI Longitude: 80° 52.7' W ( -80.87830)
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.