On April 1, 2008, about 0900 Alaska daylight time, a tailwheel and tundra tire-equipped Piper PA-22 airplane, N5840Z, sustained substantial damage when it nosed over during the landing roll at a remote, ice-covered lake, about 15 miles northeast of Ugashik, Alaska. The airplane was operated by the pilot as a visual flight rules (VFR) local area personal flight under Title 14, CFR Part 91, when the accident occurred. The airline transport certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed, and no flight plan was filed. The flight originated at the Ugashik Airport, about 0830. A Federal Aviation Administration (FAA) inspector, Anchorage Flight Standards District Office (FSDO), Anchorage, Alaska, reported that he received a telephone call from the pilot. The pilot told the inspector that during the landing roll on the lake, the main landing gear tires encountered an area of water, and the airplane nosed over. The airplane received structural damage to the wings, wing lift struts, and the vertical stabilizer.