NOAA Charting - Unimak Pass Unimak, Alaska

We conducted hydrographic surveys in this critical shipping waterway using shallow-water multibeam sonar. The bathymetry was acquired using the hydrographic survey vessel R/V Kittiwake, a steel hull vessel, 30.3 meters in length.

The final depth information was submitted in digital form as CARIS BASE surfaces and also in Bathymetric Attributed Grid (BAG) formats that best represented the sea floor at the time of the survey.

Sounding data was tide adjusted using final tide levels for the historic U.S. Coast & Geodetic Survey (USC&GS) tide station at Cape Sarichef on Unimak Island.

The survey identified a sunken cargo vessel that had never been charted. A review of the Department of the Interior, Minerals Management Service, Alaska Outer Continental Shelf Regions online database, produced an entry suggesting that the wreck was the 551' M/V Pan Nova, a Korean freighter carrying a load of wheat that sank five nautical miles north of Akun Island following a collision with another Korean freighter in the Unimak Pass area on September 10, 1983.

TerraSond was awarded another task in 2009 to complete the survey of Unimak Pass. The survey completion will require 100% multibeam coverage of 748 square nautical miles. The project is currently underway with the 180' R/V Bluefin and 30' Mt. Augustine, two Reson 8101 multibeam sonar systems, tertiary tide gauges and post processed kinematic GPS (PPK).

Back to top