U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) To reach the tidal bench marks from the Ted Stevens Anchorage International Airport, follow International Airport Road 3.8 km (2.4 mi) east to the northbound Minnesota exit, proceed north 5.5 km (3.4 mi) to 6th Avenue and turn right, proceed 0.9 km (0.5 mi) east to A Street and turn left, proceed north 0.9 km (0.6 mi) and to the Port Exit in the right lane, follow this curving exit road which becomes Ocean Dock Road 1.0 km (0.6 mi) through two security check points, veer to the right as the road becomes Anchorage Port Road and continue north 0.8 km (0.5 mi) to the POL-1 dock. The tide house is located in the green metal building at the very south end of the POL-1 dock. The bench marks are located from the Port of Anchorage Building south 1.3 km (0.8 mi) to the railroad yard near the Port Exit from A Street. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: NO 15 RESET 1966 DESIGNATION: 945 5920 TIDAL 15 1966 MONUMENTATION: Bench Mark disk VM#: 1332 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: TT0711 SETTING CLASSIFICATION: Concrete dock OPUS PID: LATITUDE: 61° 14.4' N ( 61.23953) LONGITUDE: 149° 53.3' W (-149.88769) The primary bench mark is a disk set flush with the concrete surface of the Anchorage City Dock, 101 m ( (330 ft) NW of bench mark 5920 B 1980, 9.45 m (31.0 ft) S of the N edge of the dock, 4.85 m (15.9 ft) NW of the NE corner of the Port of Anchorage Office building, 3.84 m (12.6 ft) NE of the N door of the office, and 2.87 m (9.4 ft) E of a 1 m (4 ft) high concrete deck landing for the office N door.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 5920 B 1980 DESIGNATION: 945 5920 B MONUMENTATION: Tidal Station disk VM#: 1336 AGENCY: National Ocean Survey (NOS) IDB PID: SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID: LATITUDE: 61° 14.3' N ( 61.23914) LONGITUDE: 149° 53.2' W (-149.88586) The bench mark is a disk set near the NW corner of the blue and white repair shop building belonging to the Port of Anchorage, 101 m (330 ft) SE of bench mark NO 15 RESET 1966, 27 m (90 ft) S of light pole LP 5, 0.98 m (3.2 ft) N of the NW edge of a 5 m (15 ft) wide doorway, and 0.37 m (1.2 ft) NE of NW corner of the repair shop. The bench mark is 0.06 m (0.2 ft) below ground, being the top of a disk set on a copper-clad steel rod driven to a depth of 21.6 m (71 ft) and encased in a 4-inch PVC pipe. BENCH MARK STAMPING: 5920 G 2011 DESIGNATION: 945 5920 G MONUMENTATION: Tidal Station disk VM#: 20098 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Utility vault OPUS PID#: BBFH14 LATITUDE: 61° 14.1' N ( 61.23506) LONGITUDE: 149° 53.2' W (-149.88714) The bench mark is a disk set in a 1.80 m X 2.10 m concrete utility vault located on the W side of Tidewater Road, 25.30 m (83.0 ft) E of the most eastern rail of the railroad tracks that run N and S 8.30 m (27.2 ft) W of the centerline of Tidewater Road, and 7.30 m (23.9 ft) S of a yellow fire hydrant.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 5920 H 2011 DESIGNATION: 945 5920 H MONUMENTATION: Tidal Station disk VM#: 20099 AGENCY: National Ocean Service (NOS) IDB PID: SETTING CLASSIFICATION: Concrete sidewalk OPUS PID#: BBFH52 LATITUDE: 61° 13.8' N ( 61.23025) LONGITUDE: 149° 53.4' W (-149.89022) The bench mark is a disk set in a concrete sidewalk on the W side of Chevron Corporation at 459 W Bluff Road, 12.25 m (40.1 ft) N of the centerline of W Bluff Road, 1.60 m (5.2 ft) NW of the SW corner of the Chevron Building, 1.20 m (3.9 ft) E of the most eastern rail road track, and 0.20 m (0.65 ft) above ground level. BENCH MARK STAMPING: 945 5920 J 2014 DESIGNATION: 945 5920 J MONUMENTATION: Bench Mark disk VM#: 21300 AGENCY: National Ocean Service IDB PID: SETTING CLASSIFICATION: Concrete step OPUS PID: LATITUDE: 61° 14.2' N ( 61.23667) LONGITUDE: 149° 53.2' W (-149.88597) The bench mark is a surface disk set in a large concrete stair pad at the entrance to the horizon lines building at 1717 port road, 20 m (65.6 ft) S of NW corner of brick building, 6.5 m (21.3 ft) east of N of 2 flag poles, 2.5 m (8.2 ft) W of main building wall, 0.7 m (2.3 ft) above grade.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 945 5920 K 2014 DESIGNATION: 945 5920 K MONUMENTATION: Bench Mark disk VM#: 21301 AGENCY: National Ocean Service IDB PID: SETTING CLASSIFICATION: Top of concrete base OPUS PID: LATITUDE: 61° 13.9' N ( 61.23250) LONGITUDE: 149° 53.3' W (-149.88834) The bench mark is a disk set in a 2 m (6.6 ft) x 2 meter concrete base of a 3.5 m (11.5 ft) bronze propeller monument SW of the port security building at 311 Anchorage port road. Set in the NW corner of the concrete pad, 19.5 m (64.0 ft) SW of the SW corner of the port security building, 14.7 m (48.2 ft) E of the E spur railroad tracks, 3.5 m (11.5 ft) WSW of fire hydrant 1030 #904. BENCH MARK STAMPING: 945 5920 L 2014 DESIGNATION: 945 5920 L MONUMENTATION: Bench Mark disk VM#: 21302 AGENCY: National Ocean Service IDB PID: SETTING CLASSIFICATION: Disk set in concrete silo base OPUS PID: LATITUDE: 61° 13.9' N ( 61.23228) LONGITUDE: 149° 53.5' W (-149.89153) The bench mark is W of the port security building at 311 Anchorage port road and NW of the intersection of roger graves and Anchorage port rd. The bench mark disk set in SW corner of 20 m (65.6 ft) x 30 m (98.4 ft) concrete pad with 6 cement powder storage silos. 10.5 m (34.4 ft) W of centerline of concrete pad. 5.3 m (17.4 ft) S of center line weld on SW most of 6 steel silos. 0.2 m (0.7 ft) N of SW corner of concrete pad.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 5920 THERMO 1 1988 DESIGNATION: 945 5920 THERMO 1 ALIAS: THERMO 1 RESET MONUMENTATION: Tidal Station disk VM#: 23023 AGENCY: National Ocean Service IDB PID: SETTING CLASSIFICATION: Thermopile deep rod OPUS PID#: BBBH31 LATITUDE: 61° 14.0' N ( 61.23358) LONGITUDE: 149° 53.3' W (-149.88781) The bench mark is an aluminum disk located W of Tesoro Alaska at 1331 Tidewater Road at the intersection of Terminal Road and Anchorage Port Road, 21.85 m (71.5 ft) W of the first light pole E of the intersection on the N side of Terminal Rd, 7.06 m (23.2 ft) NNE of the stop sign, 6.92 m (22.7 ft) E of the eastern-most rail of the railroad tracks, and 1.62 m (5.3 ft) W of a 0.6 m (2 ft) high 6-inch square concrete post. The bench mark is set 0.15 m (0.5 ft) above ground level, attached to a 1-inch diameter 3.20 m (10.5 ft) long thermopile cylinder driven to a depth of 3.1 m (10 ft), and encased in a 4-inch PVC pipe with concrete kick block.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) T I D A L D A T U M S Tidal datums at ANCHORAGE, KNIK ARM, COOK INLET based on: LENGTH OF SERIES: 19 YEARS TIME PERIOD: Jan '83 - Dec '01 & Jan '97 - Dec '01 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: HIGHEST OBSERVED WATER LEVEL (11/06/2002) = 10.624 MEAN HIGHER HIGH WATER MHHW = 8.889 MEAN HIGH WATER MHW = 8.667 MEAN SEA LEVEL MSL = 5.020 MEAN TIDE LEVEL MTL = 4.676 North American Vertical Datum NAVD88 = 3.284 MEAN LOW WATER MLW = 0.685 MEAN LOWER LOW WATER MLLW = 0.000 LOWEST OBSERVED WATER LEVEL (12/25/1999) = -1.949 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW NO 15 RESET 1966 11.320 2.653 5920 B 1980 11.876 3.209 5920 G 2011 11.368 2.701 5920 H 2011 11.702 3.035 945 5920 J 2014 12.288 3.621 945 5920 K 2014 11.835 3.168 945 5920 L 2014 11.974 3.307 5920 THERMO 1 1988 11.337 2.670
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 7 of 7 Station ID: 9455920 PUBLICATION DATE: 07/03/2019 Name: ANCHORAGE, KNIK ARM, COOK INLET AK NOAA Chart: 16664 Latitude: 61° 14.2' N ( 61.23750) USGS Quad: ANCHORAGE A-8 Longitude: 149° 53.4' W (-149.89040) 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.