U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) To reach the station from route 48 at the intersection with main road route 25, turn onto main rd/route 25 and proceed south 1.5 km (0.9 mi) to the intersection with front street, turn right and proceed west 0.25 km (0.15 mi) to the parking lot on the left for the greenport us post office at 131 front street, turn into the parking lot and continue on foot south 0.1 km (0.1 mi) into mitchell park and marina and the tide station at the nw corner of the marina. The bench marks are in mitchell park, near the long island railroad train station, an along the streets of greenport. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 1907 B 2014 DESIGNATION: 851 1907 B MONUMENTATION: Flange-encased Rod VM#: 21023 AGENCY: National Ocean Service IDB PID#: SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID#: BBDM08 LATITUDE: 41° 6.1' N ( 41.10114) LONGITUDE: 72° 21.7' W ( -72.36128) The primary bench mark is a flange encased rod set in the grass below the wooden boardwalk, 14.03 m (46.0 ft) NW of a storm drain, 8.70 m (28.5 ft) NE of the E side of the wood dock, 5.10 m (16.7 ft) WSW of the center of the lowest step in the stone stairs leading to the gravel path, 4.32 m (14.2 ft) ESE of the boardwalk and 2.95 m (9.7 ft) S of a light pole.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1907 A 2014 DESIGNATION: 851 1907 A MONUMENTATION: Flange-encased Rod VM#: 21024 AGENCY: National Ocean Service IDB PID#: SETTING CLASSIFICATION: Stainless steel rod in sleeve OPUS PID: LATITUDE: 41° 6.1' N ( 41.10156) LONGITUDE: 72° 21.6' W ( -72.36017) The bench mark is a flange encased rod set in the grass lawn, 20.01 m (65.6 ft) NNW of the inside face of the wood seawall, 16.03 m (52.6 ft) NE of the center of the entrance door to the camera obscura, 14.40 m (47.2 ft) SE of the SE corner of the restroom building and 14.15 m (46.4 ft) SW of the NW corner of the harbor masters building.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) T I D A L B E N C H M A R K S BENCH MARK STAMPING: TIDAL 4 STA II 29 DESIGNATION: TIDAL 4 STA II 29 MONUMENTATION: Stone Monument VM#: 21025 AGENCY: Unknown IDB PID#: LX0243 SETTING CLASSIFICATION: Stone post set into the sidewalk OPUS PID: LATITUDE: 41° 6.3' N ( 41.10483) LONGITUDE: 72° 21.6' W ( -72.35925) The bench mark is a stone post set in the sidewalk, 15.59 m (51.1 ft) NNE of a power pole with metal tag nyt12, 9.31 m (30.5 ft) SSW of the SW corner of the house porch at 84 central street, 8.29 m (27.2 ft) NNE of the manhole cover near the center of the street intersection and 2.87 m (9.4 ft) NW of the stop sign on the N side of central avenue. BENCH MARK STAMPING: 1907 C 2014 DESIGNATION: 851 1907 C MONUMENTATION: Bench Mark disk VM#: 21026 AGENCY: National Ocean Service IDB PID#: SETTING CLASSIFICATION: Concrete pad. OPUS PID: LATITUDE: 41° 6.0' N ( 41.09958) LONGITUDE: 72° 21.8' W ( -72.36292) The bench mark is a disk set in the concrete slab for the bicycle storage lockers, 12.77 m (41.9 ft) WSW of the base of the decorative ship anchor, 10.94 m (35.9 ft) S of the S most rail of the pair of long island railroad tracks, 5.35 m (17.6 ft) S of the SW corner of a rectangular storm drain, 4.98 m (16.3 ft) NE of the NE corner of the bus shelter and 0.13 m (0.4 ft) ENE of the E side of the bicycle storage lockers.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) T I D A L B E N C H M A R K S BENCH MARK STAMPING: Z 325 DESIGNATION: Z 325 1943 MONUMENTATION: Bench Mark disk VM#: 21027 AGENCY: U.S. Coastal Geodetic Survey IDB PID#: LX0237 SETTING CLASSIFICATION: Set in a culvert OPUS PID: LATITUDE: 41° 5.9' N ( 41.09853) LONGITUDE: 72° 22.6' W ( -72.37636) The bench mark is a disk set in the top of a concrete headwall for a culvert on the N side of route 25, 38.74 m (127.1 ft) ENE of a fire hydrant, 31.08 m (102.0 ft) WSW of the centerline of a private driveway, 26.00 m (85.3 ft) WSW of a power pole with no tag, 6.65 m (21.8 ft) NNW of the road centerline, 4.08 m (13.4 ft) ENE of a power pole with no tag, 0.2 m (0.7 ft) S of the N end of the culvert, 0.69 m (2.3 ft) above the ground and 0.25 m (0.8 ft) below the asphalt road.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) T I D A L D A T U M S Tidal datums at GREENPORT, GREENPORT HARBOR based on: LENGTH OF SERIES: 3 MONTHS TIME PERIOD: May 2014 - July 2014 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8461490 NEW LONDON, THAMES RIVER Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 0.885 MEAN HIGH WATER MHW = 0.799 MEAN SEA LEVEL MSL = 0.441 MEAN TIDE LEVEL MTL = 0.426 MEAN LOW WATER MLW = 0.054 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 1907 B 2014 2.273 1.474 1907 A 2014 1.951 1.152 TIDAL 4 STA II 29 3.540 2.741 1907 C 2014 2.595 1.796 Z 325 4.133 3.334
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 8511907 PUBLICATION DATE: 11/06/2014 Name: GREENPORT, GREENPORT HARBOR NY NOAA Chart: 12358 Latitude: 41° 6.1' N ( 41.10100) USGS Quad: GREENPORT Longitude: 72° 21.7' W ( -72.36117) 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.