U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) To reach the tidal bench marks from the intersection of State Highway A1A and the Mayport Ferry proceed NE on State Highway A1A for 1.0 km (0.6 mi) to Fort George Road, then north on Fort George Road for 0.8 km (0.5 mi) to Palmetto Avenue, then north on Palmetto Avenue for 3.0 km (2.0 mi) to the Kingsley Plantation, follow the western leading drive to the NW corner of the plantation property. The bench marks are located in the area around the Park Ranger residence. The tide gage and staff were located on a free-standing structure, 61.0 m (200.0 ft) NW of the NW corner of the largest white house on the plantation, and 15.0 m (50.0 ft) north of the shoreline. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 0186 A 1978 DESIGNATION: 872 0186 A TIDAL MONUMENTATION: Tidal Station disk VM#: 5062 AGENCY: National Ocean Survey (NOS) IDB PID#: BC1395 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 26.4' N ( 30.44028) LONGITUDE: 81° 26.3' W ( -81.43889) The primary bench mark is a disk set in a round concrete monument, flush with the ground, 40.0 m (130.0 ft) NW of the 2-story building referred to as the Army-Navy Club, 14.9 m (49.0 ft) SSW of the NW corner and inline with the west side of a wood bulkhead along the Fort George River, 14.3 m (47.0 ft) SSW of the NW corner of a wooden sea wall, 7.9 m (26.0 ft) NE of a 91.4 cm (36.0 in) oak tree, 5.0 m (16.5 ft) east of a 81.3 cm (32.0 in) oak tree, 0.3 m (1.0 ft) south of the south edge of a walking path, 0.3 m (1.0 ft) south of the south edge of a walking path and 0.2 m (0.5 ft) north of a carsonite witness post. NOTE: A magnet was buried at the south side of the monument.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: FT GEORGE NO 1 RESET 1977 DESIGNATION: FT GEORGE 1 RESET MONUMENTATION: Vertical Control disk VM#: 5059 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: BC1394 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 26.4' N ( 30.43972) LONGITUDE: 81° 26.2' W ( -81.43722) The bench mark is a disk set in the top of a round concrete monument flush with the ground, 59.9 m (196.5 ft) NE of the center of a brick and concrete cistern, 56.1 m (184.0 ft) east of the center of the easternmost wall of the Kingsley house, 23.9 m (78.5 ft) NNE of bench mark FT. GEORGE NO 2 RESET 1977, 7.0 m (23.0 ft) south of the top of the bank of the Ft. George River, and 6.1 m (20.0 ft) SE of a 61.0 cm (24.0 in) cypress tree. NOTE: A magnet was buried at the south side of the monument.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: FT GEORGE NO 2 RESET 1977 DESIGNATION: FT GEORGE 2 RESET MONUMENTATION: Vertical Control disk VM#: 5060 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: BC1393 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 26.4' N ( 30.43944) LONGITUDE: 81° 26.2' W ( -81.43722) The bench mark is a disk set in the top of a round concrete monument flush with the ground, 57.6 m (188.9 ft) ESE of the center of the easternmost wall of the Kingsley house, 46.4 m (152.3 ft) ENE of the center of a brick and concrete cistern, 23.9 m (78.5 ft) SSW of bench mark FT GEORGE NO 1 RESET 1977, and 16.5 m (54.2 ft) NNE of bench mark FT GEORGE NO 3 RESET 1977, and 9.9 m (32.5 ft) east of the east side of a 91.4 cm (36.0 in) hickory tree. NOTES: The mark can be located with a metal detector. A magnet was buried at the south side of the monument.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: FT GEORGE NO 3 RESET 1977 DESIGNATION: FT GEORGE 3 RESET MONUMENTATION: Vertical Control disk VM#: 5061 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: BC1392 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 26.4' N ( 30.43944) LONGITUDE: 81° 26.2' W ( -81.43722) The bench mark is a disk set in the top of a round concrete monument and flush with the ground, 45.0 m (147.0 ft) east of the center of a brick and concrete cistern, 37.3 m (122.4 ft) NE of the NE corner of the stable and carriage house, 63.3 m (214.4 ft) SE of the easternmost wall of the Kingsley house, 16.5 m (54.2 ft) south of bench mark FT GEORGE NO 2 RESET 1977, and 1.3 m (4.1 ft) west of a carsonite witness post. NOTE: A magnet was buried on the south side of the monument. BENCH MARK STAMPING: 0186 E 1978 DESIGNATION: 872 0186 E TIDAL MONUMENTATION: Tidal Station disk VM#: 5063 AGENCY: National Ocean Survey (NOS) IDB PID#: BC1391 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 26.2' N ( 30.43667) LONGITUDE: 81° 26.3' W ( -81.43889) The bench mark is a disk set in a concrete monument, level with the ground, 88.0 m (290.0 ft) west of the centerline of the gravel drive to Kingsley Plantation, 5.0 m (18.0 ft) SW of the SW corner of the seventh (last) slave quarter west of Palmetto Road, 9.8 m (32.2 ft) WNW of the SE corner of the slave quarter, 1.5 m (5.0 ft) SW of a 38.1 cm (15.0 in) oak tree marked with an "X", 1.8 m (6.0 ft) above ground level, 1.8 m (6.0 ft) north of a carsonite witness post and 1.6 m (5.1 ft) north of a 35.6 cm (14.0 in) palmetto palm. NOTE: A magnet was buried at the south side of the monument.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: Q 324 1970 DESIGNATION: Q 324 MONUMENTATION: Bench Mark disk VM#: 19266 AGENCY: US Coast and Geodetic Survey (USC & GS) IDB PID#: BC0442 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 30° 25.5' N ( 30.42417) LONGITUDE: 81° 26.0' W ( -81.43353) The bench mark is a disk set in the top of a concrete post projecting 5.1 cm (2.0 in) above the level of the ground on the grounds of Kingsley Plantation on Fort George Island, about 1.8 km (1.1 mi) south of the north end of the island, 5.8 m (19.0 ft) east of the center line of the avenue, 11.0 m (36.0 ft) south of a power line pole with two transformers, 0.5 m (1.5 ft) east of the ground end of a guy wire, 0.5 m (1.5 ft) north of a metal witness post, and 0.3 m (1.0 ft) above the level of Palmetto Avenue.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) T I D A L D A T U M S Tidal datums at FORT GEORGE ISLAND based on: LENGTH OF SERIES: 6 MONTHS TIME PERIOD: April 1978 - September 1978 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8720220 MAYPORT (FERRY DEPOT), SAINT JOHNS RIVER Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 1.591 MEAN HIGH WATER MHW = 1.500 North American Vertical Datum NAVD88 = 0.906 MEAN SEA LEVEL MSL = 0.799 MEAN TIDE LEVEL MTL = 0.772 MEAN LOW WATER MLW = 0.043 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 0186 A 1978 3.413 1.913 FT GEORGE NO 1 RESET 1977 3.758 2.258 FT GEORGE NO 2 RESET 1977 3.871 2.371 FT GEORGE NO 3 RESET 1977 3.978 2.478 0186 E 1978 3.057 1.557 Q 324 1970 5.148 3.648 Foot Notes: Geodetic heights of the bench marks meet all NOAA/NOS/NGS quality control standards for Second Order, Class 1 leveling. It is advised that a confirmation set of levels be established for bench mark Q 324 1970 to verify height differences before using tidal bench mark elevation information.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 7 of 7 Station ID: 8720186 PUBLICATION DATE: 11/20/2009 Name: FORT GEORGE ISLAND FL NOAA Chart: 11490 Latitude: 30° 26.4' N ( 30.44000) USGS Quad: MAYPORT Longitude: 81° 26.3' W ( -81.43830) 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.