U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 9451247 PUBLICATION DATE: 09/11/2008 Name: MONTE CARLO ISLAND AK NOAA Chart: 17372 Latitude: 55° 32.1' N ( 55.53500) USGS Quad: PETERSBURG (C-6) Longitude: 133° 46.0' W (-133.76700) To reach the bench marks from Point Baker on the north tip of Prince of Wales Island via boat, go approximately 20.8 km (11.2 nm) NNW crossing Sumner Strait to Monte Carlo Island at the southern part of the entrance to Keku Straits. The tide gauge location is on the north corner of the western shore of the large bight on the north side of the island. The tidal bench marks are located on the beach. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 4 1937 DESIGNATION: 945 1247 TIDAL 4 MONUMENTATION: Tidal Station disk VM#: 18607 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 56° 32.1' N ( 56.53500) LONGITUDE: 133° 46.1' W (-133.76800) The primary bench mark is a disk set on the top of a NNE/SSW oriented rock outcrop at a 90 degree bend in the rock beach, approximately 91 m (300 ft) SSW of bench mark 945 1247 TIDAL 5, 7.71 m (25.3 ft) west of the approximate MHW line, 6.19 m (20.3 ft) east of the brush and tree line, 2.38 m (7.8 ft) NNE of the SSW end of the rock outcrop and approximately 2 m (5 ft) higher than the adjacent rock immediately to the west.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 9451247 PUBLICATION DATE: 09/11/2008 Name: MONTE CARLO ISLAND AK NOAA Chart: 17372 Latitude: 55° 32.1' N ( 55.53500) USGS Quad: PETERSBURG (C-6) Longitude: 133° 46.0' W (-133.76700) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 5 1937 DESIGNATION: 945 1247 TIDAL 5 MONUMENTATION: Tidal Station disk VM#: 18608 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Rock outcrop OPUS PID#: BBBG77 LATITUDE: 56° 32.1' N ( 56.53500) LONGITUDE: 133° 46.0' W (-133.76700) The bench mark is a disk set on the top of a NNE/SSW oriented rock islet which drops off rapidly to the east, approximately 91 m (300 ft) NNE of bench mark 945 1247 Tidal 4, approximately 60 m (197 ft) south of bench mark 945 1247 TIDAL 6, 21.21 m (69.6 ft) SSW of the MHW line at the NNE end of the islet, 16.09 m (52.8 ft) NNE of the SSW end of the islet, and 2.0 m (6.6 ft) WNW of the MHW line. BENCH MARK STAMPING: 6 1937 DESIGNATION: 945 1247 TIDAL 6 MONUMENTATION: Tidal Station disk VM#: 18609 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 56° 32.1' N ( 56.53500) LONGITUDE: 133° 46.0' W (-133.76700) The bench mark is a disk set in the highest point of a solid rock outcrop which becomes an island at high tide, approximately 60 m (197 ft) north of bench mark 945 1247 TIDAL 5, 4.39 m (14.4 ft) SSW of the approximate MHW line, and 2.3 m (7.5 ft) NNE of the approximate MHW line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 9451247 PUBLICATION DATE: 09/11/2008 Name: MONTE CARLO ISLAND AK NOAA Chart: 17372 Latitude: 55° 32.1' N ( 55.53500) USGS Quad: PETERSBURG (C-6) Longitude: 133° 46.0' W (-133.76700) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 7 1938 DESIGNATION: 945 1247 TIDAL 7 MONUMENTATION: Tidal Station disk VM#: 18610 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 56° 32.0' N ( 56.53330) LONGITUDE: 133° 46.1' W (-133.76800) The bench mark is a disk set on the top of a NNE / SSW oriented rock outcrop, 47.49 m (155.8 ft) SSE of bench mark 945 1247 A, 16.9 m (55.4 ft) SE of the south end of a 20 m (66 ft) long gravel beach, and 3.41 m (11.2 ft) west of the approximate MHW line. BENCH MARK STAMPING: 1247 A 2007 DESIGNATION: 945 1247 A MONUMENTATION: Tidal Station disk VM#: 18611 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Rock outcrop OPUS PID: LATITUDE: 56° 32.0' N ( 56.53330) LONGITUDE: 133° 46.1' W (-133.76800) The bench mark is a disk set on the top of a black colored NNE/SSW oriented rock outcrop at the north end of a 20 m (66 ft) long gravel beach and the south end of a 15 m (49 ft) rocky beach, 47.48 m (155.8 ft) NNW of bench mark 945 1247 TIDAL 7, 16.70 m (54.8 ft) west of the tree line, 11.31 m (37.1 ft) NNE of the north end of the gravel beach, and 2 m (6 ft) west of the approximate MHW line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 9451247 PUBLICATION DATE: 09/11/2008 Name: MONTE CARLO ISLAND AK NOAA Chart: 17372 Latitude: 55° 32.1' N ( 55.53500) USGS Quad: PETERSBURG (C-6) Longitude: 133° 46.0' W (-133.76700) T I D A L D A T U M S Tidal datums at MONTE CARLO ISLAND based on: LENGTH OF SERIES: 1 MONTH TIME PERIOD: August 2007 - August 2007 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 9450460 KETCHIKAN, TONGASS NARROWS Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 3.861 MEAN HIGH WATER MHW = 3.606 MEAN TIDE LEVEL MTL = 2.028 MEAN SEA LEVEL MSL = 2.013 MEAN LOW WATER MLW = 0.450 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 4 1937 5.709 2.103 5 1937 4.880 1.274 6 1937 5.023 1.417 7 1938 4.189 0.583 1247 A 2007 4.327 0.721
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 9451247 PUBLICATION DATE: 09/11/2008 Name: MONTE CARLO ISLAND AK NOAA Chart: 17372 Latitude: 55° 32.1' N ( 55.53500) USGS Quad: PETERSBURG (C-6) Longitude: 133° 46.0' W (-133.76700) 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.