U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 8410834 PUBLICATION DATE: 11/19/2010 Name: PETTEGROVE POINT, DOCHET ISLAND ME NOAA Chart: 13398 Latitude: 45° 7.7' N ( 45.12844) USGS Quad: DEVILS HEAD Longitude: 67° 8.7' W ( -67.14467) To reach the tide station from the Post Office in Robbinston Maine travel north on US Route 1 (River Rd) 5.47 km (3.4 mi), turn right onto St. Croix Drive travel north around the bend for 0.32 km (0.2 mi) to 60 St Croix Drive on the right, on the northern end of the property near the road is the gated beginning of a dirt road, follow the dirt road generally west for 0.23 km (0.14 mi) down to the lower lawn of the same property, cross the lawn 87 m (286 ft) to the WNW to the station. The tide house was on the knoll at the end of the point out into the St Croix river and the bench marks are in the lawn and the beach surrounding it. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 0834 A 2010 DESIGNATION: 8410834 A MONUMENTATION: Tidal Station disk VM#: 19718 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: bedrock OPUS PID: LATITUDE: 45° 7.6' N ( 45.12692) LONGITUDE: 67° 8.7' W ( -67.14561) The primary bench mark is set flush in bedrock on the southern end of the beach that forms the southern side of Pettegrove Point, 61.59 m (202.1 ft) SSW of bench mark 8410834 B, 55.35 m (181.6 ft) SSW of the southern most corner of the beach shack on the point, 13.30 m (43.6 ft) SSE of the center of the end of a small ravine cut into the southern end of the bank that runs SW to NE above the beach, and 1.24 m (4.1 ft) above the beach
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 8410834 PUBLICATION DATE: 11/19/2010 Name: PETTEGROVE POINT, DOCHET ISLAND ME NOAA Chart: 13398 Latitude: 45° 7.7' N ( 45.12844) USGS Quad: DEVILS HEAD Longitude: 67° 8.7' W ( -67.14467) T I D A L B E N C H M A R K S BENCH MARK STAMPING: Unstamped DESIGNATION: 8410834 Wilson MONUMENTATION: Tidal Station disk VM#: 19719 AGENCY: US Coast & Geodetic Survey IDB PID#: QF0693 SETTING CLASSIFICATION: burried boulder OPUS PID: LATITUDE: 45° 7.7' N ( 45.12839) LONGITUDE: 67° 8.7' W ( -67.14472) The bench mark is set flush in the top of a buried boulder on the northern end of the tree and grass covered knoll near the end of Pettegrove Point, 117.9 m (386 ft) NW of bench mark 8410834 C, 46.10 m (151.2 ft) north of the center of the northwestern end of the sandbar section of the point where it meets the rocky islet end, 4.30 m (14.1 ft) south of the line where the rock changes in color from black to red, and 2.30 m (7.5 ft) north of tree line. BENCH MARK STAMPING: 0834 B 2010 DESIGNATION: 8410834 B MONUMENTATION: Tidal Station disk VM#: 19720 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: bedrock OPUS PID#: BBCB15 LATITUDE: 45° 7.6' N ( 45.12739) LONGITUDE: 67° 8.7' W ( -67.14525) The bench mark is set flush in the top of exposed bedrock on the beach that forms the southern side of the base of Pettegrove Point, 61.59 m (202.1 ft) NNE of bench mark 8410834 A, 58.13 m (190.7 ft) SE of bench mark 8410834 C, 52.90 m (173.6 ft) NE of the center of the end of a small ravine cut into the embankment above the southern end of the beach, 18.75 m (61.5 ft) SE of the southern most corner of the beach shack on the point, and 12.50 m (41.0 ft) SE of the vegetation line along the top of the beach.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 8410834 PUBLICATION DATE: 11/19/2010 Name: PETTEGROVE POINT, DOCHET ISLAND ME NOAA Chart: 13398 Latitude: 45° 7.7' N ( 45.12844) USGS Quad: DEVILS HEAD Longitude: 67° 8.7' W ( -67.14467) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 0834 C 2010 DESIGNATION: 8410834 C MONUMENTATION: Tidal Station disk VM#: 19721 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: bedrock outcrop OPUS PID#: BBBW07 LATITUDE: 45° 7.7' N ( 45.12772) LONGITUDE: 67° 8.7' W ( -67.14581) The bench mark is set flush in the top of exposed bedrock ledge extending NNE into the water on the beach that forms the northern side of the base of Pettegrove Point, 117.9 m (386 ft) SE of bench mark 8410834 WILSON, 64.32 m (211.0 ft) NE of bench mark 8410834 D, 58.13 m (190.7 ft) NW of bench mark 8410834 B, 38.94 m (127.8 ft) NNE of the northern most corner of the beach shack on the point, and 4.20 m (13.8 ft) NE of the edge of vegetation. BENCH MARK STAMPING: 0834 D 2010 DESIGNATION: 8410834 D MONUMENTATION: Tidal Station disk VM#: 19722 AGENCY: National Oceaan Service (NOS) IDB PID#: SETTING CLASSIFICATION: boulder OPUS PID: LATITUDE: 45° 7.6' N ( 45.12733) LONGITUDE: 67° 8.8' W ( -67.14628) The bench mark is set flush in the top of a partially buried 2.72 m x 1.39 m x 0.61 m (8.9 ft x 4.6 ft x 2.0 ft) boulder on the western side of the lawn at the base of Pettegrove Point, 64.32 m (211.0 ft) SW of bench mark 8410834 C, 14.17 m (46.5 ft) SSE of the centerline of the end of the dirt road that leads down to the lawn from St Croix Drive, 5.49 m (18.0 ft) east of the western edge of the lawn, and 0.61 m (2.0 ft) above grade.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 8410834 PUBLICATION DATE: 11/19/2010 Name: PETTEGROVE POINT, DOCHET ISLAND ME NOAA Chart: 13398 Latitude: 45° 7.7' N ( 45.12844) USGS Quad: DEVILS HEAD Longitude: 67° 8.7' W ( -67.14467) T I D A L D A T U M S Tidal datums at PETTEGROVE POINT, DOCHET ISLAND based on: LENGTH OF SERIES: 7 MONTHS TIME PERIOD: April 2010 - October 2010 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8410140 EASTPORT, PASSAMAQUODDY BAY Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 6.252 MEAN HIGH WATER MHW = 6.104 MEAN SEA LEVEL MSL = 3.129 MEAN TIDE LEVEL MTL = 3.121 MEAN LOW WATER MLW = 0.138 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 0834 A 2010 7.594 1.490 Unstamped 8.158 2.054 0834 B 2010 6.759 0.655 0834 C 2010 7.239 1.135 0834 D 2010 12.308 6.204
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 8410834 PUBLICATION DATE: 11/19/2010 Name: PETTEGROVE POINT, DOCHET ISLAND ME NOAA Chart: 13398 Latitude: 45° 7.7' N ( 45.12844) USGS Quad: DEVILS HEAD Longitude: 67° 8.7' W ( -67.14467) 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.