U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 8724168 PUBLICATION DATE: 03/09/2004 Name: NO NAME KEY FL NOAA Chart: 11445 Latitude: 24° 41.9' N ( 24.69830) USGS Quad: BIG PINE KEY Longitude: 81° 19.1' W ( -81.31830) To reach the tidal bench marks from the intersection of U.S. Highway 1 and County Road 940 (Key Deer Boulevard), proceed 2.7 km (1.7 mi) NW on County Road 940 to Watson Boulevard, thrn turn left and proceed east on Watson Boulevard for 5.6 km (3.5 mi), veering left at the fork to continue on State Route 4A, to its end on No Name Key. The bench marks are located along Watson Boulevard, and along a dirt road leading north from Watson Boulevard. The tide gage and staff were located on a pier at the end of Watson Boulevard. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: NO 1 1935 DESIGNATION: 872 4168 TIDAL 1 1935 MONUMENTATION: Tidal Station disk VM#: 6386 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: AA0247 SETTING CLASSIFICATION: Concrete post OPUS PID: LATITUDE: 24° 41.9' N ( 24.69830) LONGITUDE: 81° 19.1' W ( -81.31830) The primary bench mark is a disk near an abandoned concrete water tank along the dirt road, set in the top of a 0.3 x 0.3 m (1 x 1 ft) concrete post, 32 m (105 ft) north of the centerline of the boulevard, 17.4 m (57.0 ft) NE of bench mark NO 1 1973, 9.88 m (32.4 ft) north of the north side of an abandoned concrete slab, 5.09 m (16.7 ft) west of the centerline of the dirt road, 2.29 m (7.5 ft) west of the SE corner of the water tank, 0.30 m (1.0 ft) south of the south side of the water tank, and at ground level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 8724168 PUBLICATION DATE: 03/09/2004 Name: NO NAME KEY FL NOAA Chart: 11445 Latitude: 24° 41.9' N ( 24.69830) USGS Quad: BIG PINE KEY Longitude: 81° 19.1' W ( -81.31830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: NO 3 1935 DESIGNATION: 872 4168 TIDAL 3 MONUMENTATION: Tidal Station disk VM#: 6387 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: AA0249 SETTING CLASSIFICATION: Concrete post OPUS PID: LATITUDE: 24° 41.9' N ( 24.69830) LONGITUDE: 81° 19.1' W ( -81.31830) The bench mark is a disk set in the top of a 0.3 x 0.3 m (1 x 1 ft) concrete post, 29.81 m (97.8 ft) WSW of the northernmost concrete post which supports the guard rail at the east end of the boulevard, 25.66 m (84.2 ft) SW of the SE corner of a concrete slab, 21.15 m (69.4 ft) SSW of bench mark NO 1 1973, 5.49 m (18.0 ft) south of the centerline of the boulevard, and at ground level. BENCH MARK STAMPING: NO 1 1973 DESIGNATION: 872 4168 TIDAL 1 1973 MONUMENTATION: Tidal Station disk VM#: 6388 AGENCY: National Ocean Survey (NOS) IDB PID#: AA0899 SETTING CLASSIFICATION: Concrete post OPUS PID: LATITUDE: 24° 41.9' N ( 24.69830) LONGITUDE: 81° 19.1' W ( -81.31830) The bench mark is a disk set in the top of a concrete post, 21.15 m (69.4 ft) NNE and across the boulevard from bench mark NO 3 1935, 17 m (57 ft) SW of bench mark NO 1 1935, 16 m (54 ft) north of the centerline of the boulevard, 12.56 m (41.2 ft) west of the centerline of the dirt road, 9 m (30 ft) WSW of the SE corner of a concrete slab, 0.9 m (3 ft) south of the south side of the concrete slab, and at ground level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 8724168 PUBLICATION DATE: 03/09/2004 Name: NO NAME KEY FL NOAA Chart: 11445 Latitude: 24° 41.9' N ( 24.69830) USGS Quad: BIG PINE KEY Longitude: 81° 19.1' W ( -81.31830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 4168 D 1982 DESIGNATION: 872 4168 D TIDAL MONUMENTATION: Tidal Station disk VM#: 6389 AGENCY: National Ocean Survey (NOS) IDB PID#: AA0900 SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 24° 41.9' N ( 24.69830) LONGITUDE: 81° 19.1' W ( -81.31830) The bench mark is a disk set in the top of a rock outcrop, 0.3 km (0.2 mi) west of the east end of the boulevard, 10.45 m (34.3 ft) south of the centerline of the boulevard, 7.62 m (25.0 ft) west of the centerline of a dirt road, and at road level. BENCH MARK STAMPING: 4168 E 1982 DESIGNATION: 872 4168 E TIDAL MONUMENTATION: Tidal Station disk VM#: 6390 AGENCY: National Ocean Survey (NOS) IDB PID#: AA0901 SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 24° 41.9' N ( 24.69830) LONGITUDE: 81° 19.1' W ( -81.31830) The bench mark is a disk set in the top of a rock outcrop at the north edge of a line of trees paralleling the boulevard, 0.5 km (0.3 mi) west of the east end of the boulevard, 194.55 m (638.3 ft) west of bench mark 4168 D 1982, 8.32 m (27.3 ft) south of the centerline of the boulevard, 4.69 m (15.4 ft) north of a tree with a witness sign attached, and 0.3 m (1 ft) below road level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 8724168 PUBLICATION DATE: 03/09/2004 Name: NO NAME KEY FL NOAA Chart: 11445 Latitude: 24° 41.9' N ( 24.69830) USGS Quad: BIG PINE KEY Longitude: 81° 19.1' W ( -81.31830) T I D A L D A T U M S Tidal datums at NO NAME KEY based on: LENGTH OF SERIES: 3 MONTHS TIME PERIOD: December 1973 - February 1974 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8724211 BIG PINE KEY VIADUCT Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: North American Vertical Datum NAVD88 = 0.418 MEAN HIGHER HIGH WATER MHHW = 0.345 MEAN HIGH WATER MHW = 0.266 MEAN SEA LEVEL MSL = 0.185 MEAN TIDE LEVEL MTL = 0.162 MEAN LOW WATER MLW = 0.058 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW NO 1 1935 0.965 0.699 NO 3 1935 1.059 0.793 NO 1 1973 0.950 0.684 4168 D 1982 1.521 1.255 4168 E 1982 1.487 1.221 Foot Notes: Bench marks 4168 D 1982 and 4168 E 1982 are based on one differential leveling connection and do not meet the quality control standards of the NOS. Therefore, caution should be used when deriving elevations for these marks.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 8724168 PUBLICATION DATE: 03/09/2004 Name: NO NAME KEY FL NOAA Chart: 11445 Latitude: 24° 41.9' N ( 24.69830) USGS Quad: BIG PINE KEY Longitude: 81° 19.1' W ( -81.31830) 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.