With 3.4 million square nautical miles of U.S. waters to survey and chart, Coast Survey is up against some big challenges in keeping nautical charts current, consequently NOAA joins hands with the US Coast Guard to provide the best possible safety service to shipping. With the Alaskan coast comprising 57% of the U.S. navigationally significant waters, a multi-agency partnership for hydro survey data is necessary for maritime safety. Since 2008, NOAA has been working with the U.S. Coast Guard in Alaska to improve shipping safety.