U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
To reach the tidal bench marks from the intersection of State Highway 707 and
U.S. Highway 17 in Murrells Inlet, proceed SW on Highway 17 for 7.6 km (4.7 mi)
to the entrances to Huntington State Park and Brookgreen Gardens, then turn and
proceed SE along the park entrance road for 0.24 km (0.15 mi) to an intersection
and a small guard house. The bench marks are along the park road. The tide
gage and staff were on a small offshore platform at the head of the creek, 1.1
km (0.7 mi) SE of the guard house, and 0.2 km (0.1 mi) NE of the park road.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: HB 1 1975
DESIGNATION: 866 1684 TIDAL HB 1
MONUMENTATION: Tidal Station disk VM#: 3845
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1445
SETTING CLASSIFICATION: Concrete spillway OPUS PID:
LATITUDE: 33° 30.6' N ( 33.51000) LONGITUDE: 79° 4.2' W ( -79.07000)
The primary bench mark is a disk set in the NW corner of a concrete water
leveling structure for an alligator pond, 1.1 km (0.7 mi) SE of the guard house,
5.43 m (17.8 ft) SW of the park road, and 2.80 m (9.2 ft) SE of a metal witness
post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HB 2 1975
DESIGNATION: 866 1684 TIDAL HB 2
MONUMENTATION: Tidal Station disk VM#: 3846
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1446
SETTING CLASSIFICATION: Copper clad steel rod OPUS PID:
LATITUDE: 33° 30.5' N ( 33.50830) LONGITUDE: 79° 4.0' W ( -79.06670)
The bench mark is a disk located near a power pole in the north angle of the
T-junction of a paved road running NE-SW, 1.6 km (1.0 mi) SE of the guard house,
13.41 m (44.0 ft) ENE of the centerline of the park road, 12.62 m (41.4 ft) WNW
of the centerline of the paved road leading NE/SW, 3.75 m (12.3 ft) WNW of power
pole #AQAA4/33865, and 3.38 m (11.1 ft) SW of a 0.21 m (0.7 ft) diameter lone
cedar tree. The bench mark is crimped to the top of a copper-clad steel rod
driven an unspecified depth 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 3 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HB 3 1975
DESIGNATION: 866 1684 TIDAL HB 3
MONUMENTATION: Tidal Station disk VM#: 3847
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1447
SETTING CLASSIFICATION: Copper clad steel rod OPUS PID:
LATITUDE: 33° 30.5' N ( 33.50830) LONGITUDE: 79° 4.0' W ( -79.06670)
The bench mark is a disk located near a 0.82 m (2.7 ft) diameter pine tree in
the vee of a sand road leading to a camper water dump site, 1.6 km (1.0 mi) SE
of the guard house, 48 m (159 ft) NE of bench mark HB 2 1975, 6.86 m (22.5 ft)
ESE of the centerline of the paved road, 5.76 m (18.9 ft) NNE of the pine tree,
5 m (16 ft) WSW of the centerline of the sand road, and 3.84 m (12.6 ft) NNW of
a 0.55 m (1.8 ft) diameter pine tree. The bench mark is set 12 cm (0.4 ft)
below ground level, crimped to the top of a copper-clad steel rod driven an
unspecified depth 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 4 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HB 4 1975
DESIGNATION: 866 1684 TIDAL HB 4
MONUMENTATION: Tidal Station disk VM#: 3848
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1951
SETTING CLASSIFICATION: Copper clad steel rod OPUS PID:
LATITUDE: 33° 30.7' N ( 33.51170) LONGITUDE: 79° 4.2' W ( -79.07000)
The bench mark is a disk located near the rear of a wooded picnic area, about
1.0 km (0.6 mi) SE of the guard house, 62.79 m (206.0 ft) WSW of bench mark HB 5
1975, 41 m (134 ft) WSW of the centerline of the park road, 12 m (39 ft) SW of a
triangle-blazed 0.21 m (2.2 ft) diameter oak tree, and 9 m (29 ft) NNW of a
triangle-blazed 0.73 m (2.4 ft) diameter pine tree. The bench mark is set 12 cm
(0.4 ft) below ground level, crimped to the top of a copper-clad steel rod
driven 3.0 m (10 ft) to refusal, and encased in a 4-inch PVC pipe and concrete
kickblock. NOTE: The bench mark has a crossed-out 3 preceeding the 4. Mark not
found in 1990 by NGS.
BENCH MARK STAMPING: HB 6 1986
DESIGNATION: 866 1684 TIDAL HB 6
MONUMENTATION: Tidal Station disk VM#: 3850
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1952
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 33° 30.6' N ( 33.51000) LONGITUDE: 79° 4.2' W ( -79.07000)
The bench mark is a disk set in the top of a concrete monument near the SE leg
of a sign board near a lagoon floodgate, about 1.1 km (0.7 mi) SE of the guard
house, 18.32 m (60.1 ft) SSE of bench mark HB 1 1975, 11.13 m (36.5 ft) WSW of
the wooden no parking sign post, 7.13 m (23.4 ft) SW of the park road, and 0.52
m (1.7 ft) SE of the leg of the sign board. NOTE: Mark not found in 1990 by
NGS.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
T I D A L D A T U M S
Tidal datums at OAKS CREEK, UPPER END, MURRELLS INLET based on:
LENGTH OF SERIES: 9 MONTHS
TIME PERIOD: May 1975 - January 1976
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8661559 SMITH'S DOCK, MURRELLS INLET
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.510
MEAN HIGH WATER MHW = 1.386
North American Vertical Datum NAVD88 = 0.830
MEAN SEA LEVEL MSL = 0.764
MEAN TIDE LEVEL MTL = 0.723
MEAN LOW WATER MLW = 0.060
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
HB 1 1975 2.855 1.469
HB 2 1975 2.179 0.793
HB 3 1975 2.411 1.025
HB 4 1975 1.955 0.569
HB 6 1986 2.562 1.176
Foot Notes:
Bench mark HB 6 1986 is based on one differential leveling connection and does
not meet the quality control standards of the NOS. Therefore, caution should be
used when deriving elevations for this mark.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8661684 PUBLICATION DATE: 06/16/2004
Name: OAKS CREEK, UPPER END, MURRELLS INLET
SC
NOAA Chart: 11535 Latitude: 33° 30.7' N ( 33.51170)
USGS Quad: BROOKGREEN Longitude: 79° 4.1' W ( -79.06830)
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.