On August 9, 2001, about 2000 Alaska daylight time, a float-equipped Cessna 180H airplane, N2716X, received substantial damage when it collided with a sandbar during takeoff from the Alexander River, located about 20 miles southwest of Big Lake, Alaska. The airline transport certificated pilot and the sole passenger were not injured. The 14 CFR Part 91 local personal flight departed Lake Hood, Anchorage, Alaska, about 1700. The flight operated in visual meteorological conditions without a flight plan. During a telephone interview with the NTSB investigator-in-charge on August 13, the pilot related he initiated a takeoff from the Alexander River near its confluence with the Susitna River. The pilot said the right float struck a sandbar he didn't see, and the right float collapsed. The right wing subsequently hit the sandbar, and received substantial damage.