U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 8724964 PUBLICATION DATE: 09/27/2010 Name: COON KEY PASS, GULLIVAN BAY FL NOAA Chart: 11429 Latitude: 25° 53.8' N ( 25.89670) USGS Quad: MARCO ISLAND Longitude: 81° 38.2' W ( -81.63670) To reach the tidal bench marks from Goodland, proceed by boat SE through Cook Key Pass for 2.6 km (1.8 nm) to the SW end of Tripod Key. The bench marks are located on the highest ridge on the SW end of Tripod Key. The tide gage and staff were located on a small offshore platform, about 18 m (60 ft) SW of the SW end of Tripod Key. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 4964 A 1978 DESIGNATION: 872 4964 A TIDAL MONUMENTATION: Tidal Station disk VM#: 9725 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Galvanized steel rod OPUS PID: LATITUDE: 25° 53.8' N ( 25.89670) LONGITUDE: 81° 38.2' W ( -81.63670) The primary bench mark is a disk located on the shoreline, 56 m (184 ft) WNW of bench mark 4964 C 1978, 0.34 m (1.1 ft) south of a new witness sign and 0.15 m (0.5 ft) south of an old witness sign. The bench mark is 0.55 m (1.8 ft) above ground level, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft) to refusal, and encased in 6-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 8724964 PUBLICATION DATE: 09/27/2010 Name: COON KEY PASS, GULLIVAN BAY FL NOAA Chart: 11429 Latitude: 25° 53.8' N ( 25.89670) USGS Quad: MARCO ISLAND Longitude: 81° 38.2' W ( -81.63670) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 4964 B 1978 DESIGNATION: 872 4964 B TIDAL MONUMENTATION: Tidal Station disk VM#: 9726 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Galvanized steel rod OPUS PID: LATITUDE: 25° 53.8' N ( 25.89670) LONGITUDE: 81° 38.2' W ( -81.63670) The bench mark is a disk located 34 m (111 ft) ESE of bench mark 4964 A 1978, 6 m (19 ft) ESE of the approximate high water line, 0.30 m (1 ft) SW of a new witness post, and 0.15 m (0.5 ft) SW of an old witness sign. The bench mark is 3 cm (0.1 ft) above the pipe, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft) to refusal, and encased in a 4-inch steel pipe and concrete kickblock. BENCH MARK STAMPING: 4964 C 1978 DESIGNATION: 872 4964 C TIDAL MONUMENTATION: Tidal Station disk VM#: 9727 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Galvanized steel rod OPUS PID: LATITUDE: 25° 53.8' N ( 25.89670) LONGITUDE: 81° 38.2' W ( -81.63670) The bench mark is a disk located 22 m (73 ft) SE of bench mark 4964 B 1978, 20 m (66 ft) ESE of the approximate high water line, 0.37 m (1.2 ft) SW of a new witness post, and 0.15 m (0.5 ft) SW of an old witness sign. The bench mark is 3 cm (0.1 ft) above the pipe, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft) to refusal, and encased in a 4-inch steel pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 8724964 PUBLICATION DATE: 09/27/2010 Name: COON KEY PASS, GULLIVAN BAY FL NOAA Chart: 11429 Latitude: 25° 53.8' N ( 25.89670) USGS Quad: MARCO ISLAND Longitude: 81° 38.2' W ( -81.63670) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 4964 D 1978 DESIGNATION: 872 4964 D TIDAL MONUMENTATION: Tidal Station disk VM#: 9728 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Galvanized steel rod OPUS PID: LATITUDE: 25° 53.8' N ( 25.89670) LONGITUDE: 81° 38.2' W ( -81.63670) The bench mark is a disk located 17.07 m (56.0 ft) ESE of the approximate high water line, 8.05 m (26.4 ft) south of bench mark 4964 C 1978, 3 m (10 ft) NE of the approximate shoreline, 0.34 m (1.1 ft) SW of the new witness post, and 0.15 m (0.5 ft) SW of the old witness post. The bench mark is 0.21 m (0.7 ft) above ground level, crimped to the top of a galvanized steel rod driven 9.8 m (32 ft) to refusal, and encased in a 4-inch steel pipe and concrete kickblock. BENCH MARK STAMPING: 4964 F 1984 DESIGNATION: 872 4964 F TIDAL MONUMENTATION: Tidal Station disk VM#: 9729 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Stainless steel rod OPUS PID: LATITUDE: 25° 53.8' N ( 25.89670) LONGITUDE: 81° 38.2' W ( -81.63670) The bench mark is a disk located 16.61 m (54.5 ft) NW of bench mark 4964 B 1978, 15.97 m (52.4 ft) ENE of bench mark 4964 A 1978, 9 m (30 ft) NE of the approximate shoreline, and 0.46 m (1.5 ft) SW of a witness post. The bench mark is level with the ground, crimped to the top of a stainless steel rod driven 8.5 m (28 ft) to refusal, and encased in a 6-inch PVC pipe.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 8724964 PUBLICATION DATE: 09/27/2010 Name: COON KEY PASS, GULLIVAN BAY FL NOAA Chart: 11429 Latitude: 25° 53.8' N ( 25.89670) USGS Quad: MARCO ISLAND Longitude: 81° 38.2' W ( -81.63670) T I D A L D A T U M S Tidal datums at COON KEY PASS, GULLIVAN BAY based on: LENGTH OF SERIES: 2 MONTHS TIME PERIOD: March 1978 and May 1978 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8724967 MARCO ISLAND, CAXAMBAS PASS Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 1.156 MEAN HIGH WATER MHW = 1.073 MEAN TIDE LEVEL MTL = 0.631 MEAN SEA LEVEL MSL = 0.627 MEAN LOW WATER MLW = 0.189 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 4964 A 1978 1.670 0.597 4964 B 1978 1.705 0.632 4964 C 1978 2.476 1.403 4964 D 1978 2.414 1.341 4964 F 1984 1.634 0.561 Foot Notes: Bench mark 4964 F 1984 is based on one differential leveling connection and does not meet the quality control standards of the NOS. Therefore, caution should be used when deriving elevations for this mark.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 8724964 PUBLICATION DATE: 09/27/2010 Name: COON KEY PASS, GULLIVAN BAY FL NOAA Chart: 11429 Latitude: 25° 53.8' N ( 25.89670) USGS Quad: MARCO ISLAND Longitude: 81° 38.2' W ( -81.63670) 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.