U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 8468799 PUBLICATION DATE: 05/27/2003 Name: LONG NECK PT., LONG ISLAND SND CT NOAA Chart: 12368 Latitude: 41° 2.3' N ( 41.03830) USGS Quad: NORWALK SOUTH Longitude: 73° 28.8' W ( -73.48000) To reach the tidal bench marks from US Highway 1 and Rings End Road in Noroton, proceed SE on Rings End Road to Pear Tree Point Road, then south on Pear Tree Point Road to Long Neck Point Road, then south on Long Neck Point Road to the residence at 244 Long Neck Point Road. The bench marks are in the vicinity of 244 and 245 Long Neck Point Road. The tide gauge and staff were on the concrete T-shaped pier at 244 Long Neck Point Road. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 8799 A 1990 DESIGNATION: 846 8799 A MONUMENTATION: Survey disk VM#: 7462 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete platform OPUS PID: LATITUDE: 41° 2.3' N ( 41.03830) LONGITUDE: 73° 28.8' W ( -73.48000) The primary bench mark is a disk set in the top of the SW corner of a concrete platform at the east end of a concrete T-pier (platform is also the ceiling of a small boat shed at 244 Long Neck Point Road), 5 m (18 ft) west of the west edge of the lawn, 1.92 m (6.3 ft) south of the north edge of the platform, 0.37 m (1.2 ft) east of the west edge of the platform, and 0.34 m (1.1 ft) north of the south edge of the platform.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 8468799 PUBLICATION DATE: 05/27/2003 Name: LONG NECK PT., LONG ISLAND SND CT NOAA Chart: 12368 Latitude: 41° 2.3' N ( 41.03830) USGS Quad: NORWALK SOUTH Longitude: 73° 28.8' W ( -73.48000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 8799 B 1990 DESIGNATION: 846 8799 B MONUMENTATION: Survey disk VM#: 7463 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete step OPUS PID: LATITUDE: 41° 2.3' N ( 41.03830) LONGITUDE: 73° 28.8' W ( -73.48000) The bench mark is a disk set in the top of a concrete step on the east side of the log cabin at 244 Long Neck Point Road (log cabin is located at the waters edge just north of the concrete T-pier), 1.13 m (3.7 ft) north of the south edge of the upper step, 0.40 m (1.3 ft) south of the north edge, and 0.15 m (0.5 ft) east of the west edge. BENCH MARK STAMPING: 8799 C 1990 DESIGNATION: 846 8799 C MONUMENTATION: Survey disk VM#: 7464 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete slab OPUS PID: LATITUDE: 41° 2.3' N ( 41.03830) LONGITUDE: 73° 28.8' W ( -73.48000) The bench mark is a disk set in a concrete slab base of the cellar door at 244 Long Neck Point Road, 22 m (72 ft) west of the centerline of Long Neck Point Road, 4 m (14 ft) east of the SE wall of the house, and 1.68 m (5.5 ft) south of the south wall.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 8468799 PUBLICATION DATE: 05/27/2003 Name: LONG NECK PT., LONG ISLAND SND CT NOAA Chart: 12368 Latitude: 41° 2.3' N ( 41.03830) USGS Quad: NORWALK SOUTH Longitude: 73° 28.8' W ( -73.48000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 8799 D 1990 DESIGNATION: 846 8799 D MONUMENTATION: Survey disk VM#: 7465 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete slab OPUS PID: LATITUDE: 41° 2.3' N ( 41.03830) LONGITUDE: 73° 28.8' W ( -73.48000) The bench mark is a disk set in a concrete slab set flush in the ground in the driveway at 245 Long Neck Point Road, on the north side of the house and on the east side of the garage doors, 14 m (45 ft) south of the south edge of the tennis court, 2 m (7 ft) west of the front door entrance, and 1 foot (0.3 m) north of the garage door. BENCH MARK STAMPING: 8799 E 1990 DESIGNATION: 846 8799 E MONUMENTATION: Survey disk VM#: 7466 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete slab OPUS PID: LATITUDE: 41° 2.3' N ( 41.03830) LONGITUDE: 73° 28.8' W ( -73.48000) The bench mark is a disk set in a concrete slab which is the base of a telescope mount, at the NE corner of the residence at 245 Long Neck Point Road, 32 m (105 ft) NE of the NE corner of the house, 23 m (75 ft) east of the east edge of the tennis court, and 2 m (6 ft) west of the hedges on the east edge of the property.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 8468799 PUBLICATION DATE: 05/27/2003 Name: LONG NECK PT., LONG ISLAND SND CT NOAA Chart: 12368 Latitude: 41° 2.3' N ( 41.03830) USGS Quad: NORWALK SOUTH Longitude: 73° 28.8' W ( -73.48000) T I D A L D A T U M S Tidal datums at LONG NECK PT., LONG ISLAND SND based on: LENGTH OF SERIES: 3 MONTHS TIME PERIOD: June 1990 - August 1990 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8518490 NEW ROCHELLE Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 2.362 MEAN HIGH WATER MHW = 2.254 MEAN TIDE LEVEL MTL = 1.163 MEAN SEA LEVEL MSL = 1.162 MEAN LOW WATER MLW = 0.071 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 8799 A 1990 6.156 3.902 8799 B 1990 6.563 4.309 8799 C 1990 7.717 5.463 8799 D 1990 8.420 6.166 8799 E 1990 7.194 4.940
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 8468799 PUBLICATION DATE: 05/27/2003 Name: LONG NECK PT., LONG ISLAND SND CT NOAA Chart: 12368 Latitude: 41° 2.3' N ( 41.03830) USGS Quad: NORWALK SOUTH Longitude: 73° 28.8' W ( -73.48000) 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.