U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 8671086 PUBLICATION DATE: 12/19/2018 Name: SKIDAWAY INSTITUTE, SKIDAWAY RIVER GA NOAA Chart: 11512 Latitude: 31° 59.4' N ( 31.99000) USGS Quad: ISLE OF HOPE Longitude: 81° 1.4' W ( -81.02330) T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 1086 A 1994 DESIGNATION: 867 1086 A MONUMENTATION: Bench Mark disk VM#: 15748 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Concrete OPUS PID: LATITUDE: 31° 59.4' N ( 31.99000) LONGITUDE: 81° 1.4' W ( -81.02330) The primary bench mark is a disk set flush in concrete located in a wooded area surrounding the Life Science Building at Skidaway Institute, 25 m (82 ft) SE of the SE corner of the Life Science Building, 17.37 m (57.0 ft) NNE of a fire hydrant in front on the cold lab freezer, and 0.58 m (1.9 ft) west of a manhole cover located in the center of the wooded area. BENCH MARK STAMPING: 1086 B 1994 DESIGNATION: 867 1086 B MONUMENTATION: Bench Mark disk VM#: 15749 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Concrete OPUS PID: LATITUDE: 31° 59.4' N ( 31.99000) LONGITUDE: 81° 1.4' W ( -81.02330) The bench mark is a disk set flush in concrete located in at the corner of the Skidaway Institute Carpenter's shop, 60.66 m (199.0 ft) SSE of a fire hydrant located SW of white "Roebling House", 40.84 m (134.0 ft) NE of the corner of the Power House Building at the NE base of the water tower, and 0.91 m (3.0 ft) out from the front left corner of the carpenter shop.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 8671086 PUBLICATION DATE: 12/19/2018 Name: SKIDAWAY INSTITUTE, SKIDAWAY RIVER GA NOAA Chart: 11512 Latitude: 31° 59.4' N ( 31.99000) USGS Quad: ISLE OF HOPE Longitude: 81° 1.4' W ( -81.02330) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1086 C 1994 DESIGNATION: 867 1086 C MONUMENTATION: Bench Mark disk VM#: 15750 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Concrete OPUS PID: LATITUDE: 31° 59.4' N ( 31.99000) LONGITUDE: 81° 1.4' W ( -81.02330) The bench mark is a disk set flush in concrete located in the ESE corner of the concrete slab holding generator # 1 at the rear (ESE) corner of the Administration Building, 56.85 m (186.5 ft) south of the center of the left doorway on the SE side of the Hazardous Chemical Shed, and 30.48 m (100.0 ft) NW of the western leg of the water tower. BENCH MARK STAMPING: RM 2 1983 DESIGNATION: 867 1086 RM 2 MONUMENTATION: Bench Mark disk VM#: 15751 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Unspecified deep rod OPUS PID: LATITUDE: 31° 59.4' N ( 31.99000) LONGITUDE: 81° 1.4' W ( -81.02330) The bench mark is a disk located in the field behind the Administration Building at Skidaway Institute, 43.59 m (143.0 ft) west of telephone pole #58, 41.73 m (136.9 ft) SW of the SW corner of the Administration Building, and 5.61 m (18.4 ft) east of the centerline of Ocean Science Circle Road.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 8671086 PUBLICATION DATE: 12/19/2018 Name: SKIDAWAY INSTITUTE, SKIDAWAY RIVER GA NOAA Chart: 11512 Latitude: 31° 59.4' N ( 31.99000) USGS Quad: ISLE OF HOPE Longitude: 81° 1.4' W ( -81.02330) T I D A L B E N C H M A R K S BENCH MARK STAMPING: BV Oceanography 1983 DESIGNATION: 867 1086 BV MONUMENTATION: Bench Mark disk VM#: 15752 AGENCY: National Ocean Service (NOS) IDB PID#: BR1838 SETTING CLASSIFICATION: Unspecified deep rod OPUS PID: LATITUDE: 31° 59.4' N ( 31.99000) LONGITUDE: 81° 1.4' W ( -81.02330) The bench mark is a disk located in the field behind the Administration Building at Skidaway Institute, 45.23 m (148.4 ft) south of a SE&P power pole #58, 25.60 m (84.0 ft) NE of the centerline of Ocean Science Circle Road, and 1.58 m (5.2 ft) south of a GA Department of Transportation witness post.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 8671086 PUBLICATION DATE: 12/19/2018 Name: SKIDAWAY INSTITUTE, SKIDAWAY RIVER GA NOAA Chart: 11512 Latitude: 31° 59.4' N ( 31.99000) USGS Quad: ISLE OF HOPE Longitude: 81° 1.4' W ( -81.02330) T I D A L D A T U M S Tidal datums at SKIDAWAY INSTITUTE, SKIDAWAY RIVER based on: LENGTH OF SERIES: 30 DAYS TIME PERIOD: Oct 7 1994 - Nov 5 1994 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 = 2.552 MEAN HIGH WATER MHW = 2.430 MEAN SEA LEVEL MSL = 1.301 MEAN TIDE LEVEL MTL = 1.253 MEAN LOW WATER MLW = 0.075 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 1086 A 1994 3.322 0.891 1086 B 1994 3.477 1.046 1086 C 1994 4.506 2.076 RM 2 1983 4.222 1.791 BV Oceanography 1983 3.899 1.468
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 8671086 PUBLICATION DATE: 12/19/2018 Name: SKIDAWAY INSTITUTE, SKIDAWAY RIVER GA NOAA Chart: 11512 Latitude: 31° 59.4' N ( 31.99000) USGS Quad: ISLE OF HOPE Longitude: 81° 1.4' W ( -81.02330) 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.