U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) To reach the bench marks from Petersburg Ferry Terminal, drive south 0.97 km (0.6 mi) along Mitkof Hwy. The bench marks are located just south of the Fisherman's Cemetery and on either side of Mitkof Highway just south of the Fisherman's Cemetery. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 1434 A 2006 DESIGNATION: 945 1434 TIDAL A MONUMENTATION: Tidal Station disk VM#: 18109 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: OPUS PID#: BBBC62 LATITUDE: 56° 48.0' N ( 56.80000) LONGITUDE: 132° 58.8' W (-132.98000) The primary bench mark is a disk set flush in bedrock, located on the east side Mitkof Highway just south of the Fisherman's Cemetery, bearing 053 T (030 M) and 1.3 m from a yellow fire hydrant number "342", directly across the road from a pier house with a blue roof whose peak bears 293 T (270 M) and 20.0 m (65.6 ft) away, across from another pier wooden house with a red roof north of the one with the blue roof and the east peak of the red roof bearing 343 T (320 M) from bench mark 1434 A 2006, 50 m (164 ft) from bench mark 1434 B 2006 bearing 338 T (315 M), and 3.3 m (10.8 ft) above the apparent mean high water line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1434 B 2006 DESIGNATION: 945 1434 TIDAL B MONUMENTATION: Tidal Station disk VM#: 18104 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete base OPUS PID: LATITUDE: 56° 48.0' N ( 56.80000) LONGITUDE: 132° 58.8' W (-132.98000) The bench mark is a disk set fluch in a cement lamp post base on the west side of Mitkof Highway, between the road and the bike path, just north of a pierhouse with a blue roof 50 m from bennch mark 945 1434 A, 15 m (49.2 ft) from bench mark "Eye bolt", and 3.0 m (9.8 ft) above the apparent mean high water line. BENCH MARK STAMPING: 1434 C 2006 DESIGNATION: 945 1434 TIDAL C MONUMENTATION: Tidal Station disk VM#: 18105 AGENCY: National Ocean Service IDB PID#: SETTING CLASSIFICATION: Boulder OPUS PID: LATITUDE: 56° 48.0' N ( 56.80000) LONGITUDE: 132° 58.8' W (-132.98000) The bench mark is a disk set in a boulder at the high water line, 87 m (285 ft) from bench mark 945 1434 D, 62 m (203 ft) from a pier on which sits a storage house with a blue roof, 33 m (108 ft) from a pier on which sits a wooden storage house with a red roof, 21.40 m (70.2 ft) from bench mark "Eye bolt", and 0.40 m (1.3 ft) above the apparent mean high water line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1434 D 2006 DESIGNATION: 945 1434 TIDAL D MONUMENTATION: Tidal Station disk VM#: 18106 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Concrete base OPUS PID: LATITUDE: 56° 48.1' N ( 56.80170) LONGITUDE: 132° 58.8' W (-132.98000) The bench mark is a disk set flush in a circular lamp post base between Mikof Highway and the bike path located on the west side of teh road, 450 m (137 ft) SE of the red daymark "54", 87 m (285 ft) from bench mark 1434 C 2006, 55 m from the pier to the south on which a wooden pier house with a red roof sits, 30.00 m (98.4 ft) from bench mark 1434 E 2006, and 2.56 m (8.4 ft) above the apparent mean high water line. BENCH MARK STAMPING: 1434 E 2006 DESIGNATION: 945 1434 TIDAL E MONUMENTATION: Bolt VM#: 18107 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Fire hydrant OPUS PID: LATITUDE: 56° 48.1' N ( 56.80170) LONGITUDE: 132° 58.8' W (-132.98000) The bench mark is the westernmost nut on the top of a yellow fire hydrant with the number 341 stenciled in black on its side located on the east side of Mitkof Highway just south of fisherman's cemetery, 430 m (1410 ft) from the red daymark "54", 80 m (262 ft) from a pier with a wooden storage house and a red roof, 30 m (98.4 ft) from bench mark 1434 D 2006, 5.36 m (17.6 ft) above the apparent mean high water line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: DESIGNATION: 945 1434 Eye Bolt MONUMENTATION: Bolt VM#: 18108 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Boulder OPUS PID: LATITUDE: 56° 48.1' N ( 56.80170) LONGITUDE: 132° 58.8' W (-132.98000) The bench mark is a rusty eye bolt set in a boulder located between two houses, 51 m (167.3 ft) from a house with a red roof, 41 m (134.5 ft) across from a pier with a house with a blue roof, 21.4 m (70.2 ft) from bench mark 1434 C 2006, and 15.0 m (49.2 ft) from bench mark 1434 B 2006.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) T I D A L D A T U M S Tidal datums at TURN POINT based on: LENGTH OF SERIES: 41 DAYS TIME PERIOD: April 15, 2006 - May 26, 2006 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 = 4.898 MEAN HIGH WATER MHW = 4.628 MEAN TIDE LEVEL MTL = 2.543 MEAN SEA LEVEL MSL = 2.542 MEAN LOW WATER MLW = 0.458 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 1434 A 2006 8.272 3.644 1434 B 2006 7.960 3.332 1434 C 2006 5.340 0.712 1434 D 2006 9.103 4.475 1434 E 2006 10.359 5.731 945 1434 Eye Bolt 4.907 0.279
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 9451434 PUBLICATION DATE: 06/08/2009 Name: TURN POINT AK NOAA Chart: 17375 Latitude: 56° 48.0' N ( 56.80000) USGS Quad: PETERSBURG D-3 Longitude: 132° 58.8' W (-132.98000) 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.