U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8661991 PUBLICATION DATE: 07/02/2003
Name: HAGLEY, WACCAMAW RIVER
SC
NOAA Chart: 11535 Latitude: 33° 26.1' N ( 33.43500)
USGS Quad: WAVERLY MILLS Longitude: 79° 10.9' W ( -79.18170)
To reach the tidal bench marks from Pawleys Island Post Office, proceed SW on US
Highway 17 for 2.7 km (1.7 mi) to an Exxon station at the intersection with Old
Hagley Road (Hagley Boulevard), then turn right and proceed west on Old Hagley
Road for 3.4 km (2.1 mi) to a breakwater and boat ramp. The bench marks are
along Old Hagley Road, Waccamaw Trail, and Emerson Circle. The tide gauge and
staff were originally on the breakwater and in October 1977 moved to a dock with
a boathouse, just north of the breakwater.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: HL NO 1 1975
DESIGNATION: 866 1991 TIDAL HL 1
MONUMENTATION: Tidal Station disk VM#: 12082
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1392
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 33° 26.2' N ( 33.43670) LONGITUDE: 79° 10.9' W ( -79.18170)
The primary bench mark is a disk located along Old Hagley Road near the boat
ramp, 24.93 m (81.8 ft) SSE of the NE end of the north bulkhead, 19.66 m (64.5
ft) ESE of the SE end of the south bulkhead, 12.95 m (42.5 ft) SSW of the
centerline of the road, 2.50 m (8.2 ft) SE of a laurel oak tree, and 0.52 m (1.7
ft) NNW of a steel witness post with sign. The bench mark is set level with the
ground, crimped to the top of a copper-clad steel rod driven an unspecified
depth, and encased in an ABS pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8661991 PUBLICATION DATE: 07/02/2003
Name: HAGLEY, WACCAMAW RIVER
SC
NOAA Chart: 11535 Latitude: 33° 26.1' N ( 33.43500)
USGS Quad: WAVERLY MILLS Longitude: 79° 10.9' W ( -79.18170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HL NO 2 1975
DESIGNATION: 866 1991 TIDAL HL 2
MONUMENTATION: Tidal Station disk VM#: 12083
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1388
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 33° 26.2' N ( 33.43670) LONGITUDE: 79° 10.8' W ( -79.18000)
The bench mark is a disk located near the intersection of Old Hagley Road and
Waccamaw Trail, 8.20 m (26.9 ft) north of the centerline of Old Hagley Road,
6.80 m (22.3 ft) WNW of Waccamaw Trail, and 0.91 m (3.0 ft) west of an
unnumbered power pole. The bench mark is set 0.03 m (0.1 ft) above the ground,
crimped to the top of a copper-clad steel rod driven an unspecified depth, and
encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: HL NO 3 1975
DESIGNATION: 866 1991 TIDAL HL 3
MONUMENTATION: Tidal Station disk VM#: 12084
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1393
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 33° 26.2' N ( 33.43670) LONGITUDE: 79° 10.8' W ( -79.18000)
The bench mark is a disk located near the intersection of Waccamaw Trail and
Lancer Drive, 5.97 m (19.6 ft) NW of the centerline of Waccamaw Trail, 5.58 m
(18.3 ft) SW of the centerline of Lancer Drive, and 1.92 m (6.3 ft) WNW of power
pole #JAA2. The bench mark is set level with the ground, crimped to the top of
a copper-clad steel rod driven an unspecified depth, and encased in an ABS pipe
and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8661991 PUBLICATION DATE: 07/02/2003
Name: HAGLEY, WACCAMAW RIVER
SC
NOAA Chart: 11535 Latitude: 33° 26.1' N ( 33.43500)
USGS Quad: WAVERLY MILLS Longitude: 79° 10.9' W ( -79.18170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: HL NO 4 1975
DESIGNATION: 866 1991 TIDAL HL 4
MONUMENTATION: Tidal Station disk VM#: 12085
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1394
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 33° 26.2' N ( 33.43670) LONGITUDE: 79° 10.8' W ( -79.18000)
The bench mark is a disk located near the intersection of Waccamaw Trail and
Emerson Circle, 11.03 m (36.2 ft) WSW of the centerline of Emerson Circle, 5.61
m (18.4 ft) NNW of the centerline of Waccamaw Trail, and 1.74 m (5.7 ft) west of
power pole #JAA1. The bench mark is set level with the ground, crimped to the
top of a copper-clad steel rod driven an unspecified depth, and encased in an
ABS pipe and concrete kickblock.
BENCH MARK STAMPING: HL NO 5 1975
DESIGNATION: 866 1991 TIDAL HL 5
MONUMENTATION: Tidal Station disk VM#: 12086
AGENCY: National Ocean Survey (NOS) IDB PID#: DD1395
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 33° 26.3' N ( 33.43830) LONGITUDE: 79° 10.8' W ( -79.18000)
The bench mark is a disk located along Emerson Circle, 59 m (195 ft) NNE of
bench mark HL NO 4 1975, 7.92 m (26.0 ft) ENE of the centerline of Emerson
Circle, 5.61 m (18.4 ft) south of the centerline of a driveway, and 2.99 m (9.8
ft) north of power pole #JA5. The bench mark is set level with the ground,
crimped to the top of a copper-clad steel rod driven an unspecified depth, and
encased in an ABS pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8661991 PUBLICATION DATE: 07/02/2003
Name: HAGLEY, WACCAMAW RIVER
SC
NOAA Chart: 11535 Latitude: 33° 26.1' N ( 33.43500)
USGS Quad: WAVERLY MILLS Longitude: 79° 10.9' W ( -79.18170)
T I D A L D A T U M S
Tidal datums at HAGLEY, WACCAMAW RIVER based on:
LENGTH OF SERIES: 1 YEAR
TIME PERIOD: June 1979 - May 1980
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8665530 CHARLESTON, COOPER RIVER ENTRANCE
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (09/04/1979) = 1.707
MEAN HIGHER HIGH WATER MHHW = 1.170
MEAN HIGH WATER MHW = 1.102
MEAN SEA LEVEL MSL = 0.605
MEAN TIDE LEVEL MTL = 0.573
North American Vertical Datum NAVD88 = 0.530
MEAN LOW WATER MLW = 0.045
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/09/1978) = -0.601
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
HL NO 1 1975 2.528 1.426
HL NO 2 1975 3.405 2.303
HL NO 3 1975 5.064 3.962
HL NO 4 1975 5.112 4.010
HL NO 5 1975 4.869 3.767
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8661991 PUBLICATION DATE: 07/02/2003
Name: HAGLEY, WACCAMAW RIVER
SC
NOAA Chart: 11535 Latitude: 33° 26.1' N ( 33.43500)
USGS Quad: WAVERLY MILLS Longitude: 79° 10.9' W ( -79.18170)
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.