U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) To reach the tidal bench marks from the intersection of U.S. Highway 17A and State Highway 41 at Jamestown, proceed north on U.S. Highway 17A for 2.4 km (1.5 mi) to the W.H. Andrews Memorial Bridge over the Santee River. The bench marks are on the south end of the bridge, and along a dirt road to the SE of U.S. Highway 17A, just south of the bridge. The tide station was located on the SE end of the bridge. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 2405 A 1976 DESIGNATION: 866 2405 A TIDAL MONUMENTATION: Tidal Station disk VM#: 3927 AGENCY: National Ocean Survey (NOS) IDB PID#: DD1149 SETTING CLASSIFICATION: Concrete bridge abutment OPUS PID: LATITUDE: 33° 18.3' N ( 33.30500) LONGITUDE: 79° 40.7' W ( -79.67830) The primary bench mark is a disk set in the SW concrete bridge abutment, 4.39 m (14.4 ft) NE of the centerline of the bridge, 0.40 m (1.3 ft) ESE of the bridge rail, 0.15 m (0.5 ft) NNW of the end of the bridge, and 0.3 m (1.0 ft) above highway level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 2405 B 1976 DESIGNATION: 866 2405 B TIDAL MONUMENTATION: Tidal Station disk VM#: 3928 AGENCY: National Ocean Survey (NOS) IDB PID#: DD1150 SETTING CLASSIFICATION: Concrete bridge abutment OPUS PID: LATITUDE: 33° 18.3' N ( 33.30500) LONGITUDE: 79° 40.7' W ( -79.67830) The bench mark is a disk set flush in the SE concrete bridge abutment, 8.78 m (28.8 ft) SE of 2405 A 1976, 4.39 m (14.4 ft) SW of the centerline of the bridge, 2.13 m (7.0 ft) NNE of the bridge, 0.49 m (1.6 ft) ENE of the right bridge rail, 0.18 m (0.6 ft) NNE of the end of the bridge abutment, and 0.3 m (1.0 ft) above the highway. BENCH MARK STAMPING: 2405 C 1976 DESIGNATION: 866 2405 C TIDAL MONUMENTATION: Tidal Station disk VM#: 3929 AGENCY: National Ocean Survey (NOS) IDB PID#: DD1153 SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID: LATITUDE: 33° 18.2' N ( 33.30330) LONGITUDE: 79° 40.7' W ( -79.67830) The bench mark is a disk located in the treeline at the SE edge of the dirt road paralleling the SE side of the highway, 91 m (299 ft) east of bench mark 2405 G 1976, 37.92 m (124.4 ft) SSW of the SE corner of the bridge, 16.12 m (52.9 ft) SE of the centerline of the highway, 2.99 m (9.8 ft) north of a 1 m (2 ft) diameter pine tree, 2.13 m (7.0 ft) SSE of the center of the dirt road, and 0.46 m (1.5 ft) NNE of a metal witness post. The bench mark is set about 4 m (12 ft) below the highway, crimped to the top of a copper-clad steel rod driven 4.9 m (16 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 3 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 2405 E 1976 DESIGNATION: 866 2405 E TIDAL MONUMENTATION: Tidal Station disk VM#: 3931 AGENCY: National Ocean Survey (NOS) IDB PID#: DD1151 SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID: LATITUDE: 33° 18.0' N ( 33.30000) LONGITUDE: 79° 40.9' W ( -79.68170) The bench mark is a disk located between the tree line and Highway 17A at its intersection with the dirt road leading to the boat ramp just SE of the bridge, 88 m (290 ft) west of 2405 G 1976, 9.63 m (31.6 ft) SE of the centerline of the highway, 1.83 m (6.0 ft) east of the center of the dirt road leading back from the boat ramp, and 0.70 m (2.3 ft) east of a metal witness post and sign. The bench mark is set 1.49 m (4.9 ft) below the highway, crimped to the top of a copper-clad steel rod driven 4.9 m (16 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 4 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 2405 G 1982 DESIGNATION: 866 2405 G TIDAL MONUMENTATION: Tidal Station disk VM#: 3932 AGENCY: National Ocean Survey (NOS) IDB PID#: DD1152 SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID: LATITUDE: 33° 18.1' N ( 33.30170) LONGITUDE: 79° 40.8' W ( -79.68000) The bench mark is a disk located near a lone 1.28 m (4.2 ft) diameter pine tree in the treeline at the SE edge of the dirt road paralleling the SE side of the highway, 14.72 m (48.3 ft) SE of the centerline of the highway, 5.58 m (18.3 ft) north of a 1 m (3 ft) diameter pine tree, 3.14 m (10.3 ft) WSW of the 1.28 m (4.2 ft) diameter pine tree, 2.29 m (7.5 ft) SE of the center of the dirt road, and 0.88 m (2.9 ft) north of a witness post and sign. The bench mark is set about 3 m (10 ft) below the highway, crimped to the top of a copper-clad steel rod driven 7.3 m (24 ft) to refusal, and encased in a 5-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) T I D A L D A T U M S Tidal datums at JAMESTOWN BRIDGE, SANTEE RIVER based on: LENGTH OF SERIES: 4 MONTHS TIME PERIOD: May 1977 - August 1977 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: MEAN HIGHER HIGH WATER MHHW = 0.406 MEAN HIGH WATER MHW = 0.361 MEAN TIDE LEVEL MTL = 0.191 MEAN SEA LEVEL MSL = 0.179 MEAN LOW WATER MLW = 0.020 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum NAVD88 = -0.135 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 2405 A 1976 12.502 12.141 2405 B 1976 12.503 12.142 2405 C 1976 8.244 7.883 2405 E 1976 9.121 8.760 2405 G 1982 7.709 7.348 Foot Notes: Note:The tidal signal is masked at this station during periods of high river level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 8662405 PUBLICATION DATE: 06/16/2003 Name: JAMESTOWN BRIDGE, SANTEE RIVER SC NOAA Chart: 11531 Latitude: 33° 18.3' N ( 33.30500) USGS Quad: JAMESTOWN Longitude: 79° 40.7' W ( -79.67830) 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.