U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) To reach the tidal bench marks from the intersection of the FEC Railroad crossing and State Highway 706 (West Indiantown Road) in Jupiter, proceed 4.7 km (2.9 mi) west along Highway 706 to the bridge over Hungryland Slough. The bench marks are located in the area around State Highway 706. The tide gage and staff were located on a Flood Control District bulkhead just north of the locks. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 1 DESIGNATION: 1 FLDT MONUMENTATION: Tidal Station disk VM#: 5567 AGENCY: Florida Department of Transportation (FLDT) IDB PID#: AD6272 SETTING CLASSIFICATION: Concrete bridge abutment OPUS PID: LATITUDE: 26° 56.0' N ( 26.93330) LONGITUDE: 80° 8.4' W ( -80.14000) The primary bench mark is a disk set flush in the NE corner of the State Highway 706 bridge over Hungryland Slough and 0.46 m (1.5 ft) south of the north end of the abutment wingwall. NOTE: The wing wall has been removed. Mark not found in 2002 & 2003 by US Power Squadron.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) T I D A L B E N C H M A R K S BENCH MARK STAMPING: JENKINS 1970 DESIGNATION: JENKINS MONUMENTATION: Survey disk VM#: 5564 AGENCY: Florida Department of Transportation (FLDT) IDB PID#: AD6275 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 26° 56.0' N ( 26.93330) LONGITUDE: 80° 8.6' W ( -80.14333) The bench mark is a disk set in a concrete monument 69 m (227 ft) SW of the SW corner of the State Highway 706 bridge over Hungryland Slough, 50 m (165 ft) south of the centerline of the highway, 11 m (35 ft) NW of the west edge of the levee, and 0.67 m (2.2 ft) east of a metal witness post.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) T I D A L B E N C H M A R K S BENCH MARK STAMPING: JENKINS NO 2 1970 DESIGNATION: JENKINS RM 2 MONUMENTATION: Reference Mark disk VM#: 5565 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: AD6276 SETTING CLASSIFICATION: Concrete monument OPUS PID#: AD6276 LATITUDE: 26° 56.0' N ( 26.93330) LONGITUDE: 80° 8.6' W ( -80.14330) The bench mark is a disk set flush in a concrete monument, 23.71 m (77.8 ft) SW of bench mark JENKINS 1970, 17 m (57 ft) SE of the east side of a palmetto patch, 7.16 m (23.5 ft) NW of the west edge of the levee, and 0.37 m (1.2 ft) NE of a metal witness post. BENCH MARK STAMPING: 93 79 A 20 DESIGNATION: 93 79 A 20 FLDT MONUMENTATION: Tidal Station disk VM#: 5566 AGENCY: Florida Department of Transportation (FLDT) IDB PID#: AD6274 SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 26° 56.1' N ( 26.93500) LONGITUDE: 80° 8.4' W ( -80.14000) The bench mark is a disk set in the top of a concrete monument, 11.55 m (37.9 ft) west of the SW corner of the State Highway 706 bridge over Hungryland Slough, 5.39 m (17.7 ft) south of the centerline of the highway, 0.94 m (3.1 ft) north of a guardrail, and 0.73 m (2.4 ft) north of a witness post. NOTE: Mark not found in 1995, 2002 and 2003 by US Power Squadron.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 2 DESIGNATION: 2 FLDT MONUMENTATION: Tidal Station disk VM#: 5568 AGENCY: Florida State Road Department (FLSRD) IDB PID#: AD6273 SETTING CLASSIFICATION: Concrete foundation OPUS PID: LATITUDE: 26° 56.1' N ( 26.93500) LONGITUDE: 80° 8.4' W ( -80.14000) The bench mark is a disk set flush in the NW corner of State Highway 706 bridge over Hungryland Slough, and 0.46 m (1.5 ft) south of the north end of the abutment wingwall.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) T I D A L D A T U M S Tidal datums at LOXAHATCHEE RIVER LOCK based on: LENGTH OF SERIES: 2 MONTHS TIME PERIOD: December 1972 - January 1973 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8722557 NORTH PALM BEACH Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 0.677 North American Vertical Datum NAVD88 = 0.640 MEAN HIGH WATER MHW = 0.632 MEAN SEA LEVEL MSL = 0.341 MEAN TIDE LEVEL MTL = 0.341 MEAN LOW WATER MLW = 0.050 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 1 7.028 6.396 JENKINS 1970 6.701 6.069 JENKINS NO 2 1970 6.828 6.196 93 79 A 20 6.556 5.924 2 7.101 6.469
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 8722496 PUBLICATION DATE: 04/18/2005 Name: LOXAHATCHEE RIVER LOCK FL NOAA Chart: 11474 Latitude: 26° 56.1' N ( 26.93500) USGS Quad: ROOD Longitude: 80° 8.6' W ( -80.14330) 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.