On July 17, 2005, about 1345 central daylight time, a fixed-float equipped Cessna 180, N4652B, piloted by a private pilot, was substantially damaged during an aborted takeoff when it encountered rough water and nosed over on Bowstring Lake, Minnesota. The local flight was being conducted under 14 CFR Part 91 without a flight plan. Visual meteorological conditions prevailed. The pilot reported no injuries. The pilot reported that high winds were forecast and he planned to relocate his float plane to Turtle Lake for security. He stated that by the time he arrived Bowstring Lake was "rough" and the tie downs were not holding. The pilot stated that during the takeoff run he decided that it was "too rough to continue." He reported that he "let up" on the throttle and was slowing down when the left float "caught a wave" and the airplane nosed over. Wind conditions recorded by the Bigfork Municipal Airport (FOZ) Automated Weather Observing System (AWOS), located 18 nautical miles northeast of the accident site, at 1335, were from 170 degrees at 19 knots, gusting to 27 knots. The pilot reported winds from 140 degrees at 18 knots, gusting to 22 knots. The pilot stated that there were no failures or malfunctions with the aircraft prior to the accident.