On July 16, 2017, about 1515 eastern daylight time, a Cessna R172K, N736NK, was substantially damaged during landing at Brandy Pond Seaplane Base (5ME), Naples, Maine. The private pilot and passenger were not injured. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the flight that departed Biddeford Municipal Airport (B19), Biddeford, Maine. The pilot reported to local police that when the airplane landed it "bounced" and that he was "not entirely sure what happened" and felt that maybe one of the wings went into the water. In a statement provided to a Federal Aviation Administration (FAA) inspector, the pilot reported, "Upon water landing touchdown and after an otherwise normal circling approach the aircraft yaw and roll were uncontrollable. The aircraft rolled right and came to a stop with at least part of the right wing submerged." Multiple witnesses reported the water was "choppy" and "very busy" with boating activity. The landing was recorded by a boater on Brandy Pond at the time of the accident and posted on a commercial website. Examination of the video revealed rapid, abrupt rolling of the wings at a very low altitude just prior to water contact. At touchdown, the airplane bounced and then rotated back and forth about the roll axis, alternately contacting the water with the left and right pontoons. The roll oscillations increased in magnitude until the right pontoon and right wing tip dragged the water, which brought the airplane to an abrupt stop with the right wingtip submerged. One witness stated the water was rough and he thought the airplane looked high on its approach and was not landing into the wind. He stated the airplane was fast and did not decrease power until just before touchdown. Examination of the airplane by the FAA inspector revealed that the right wing and right horizontal stabilizer were substantially damaged. Flight control continuity was confirmed to all flight control surfaces. Movement of the elevator was restricted due to impact damage. The four-seat, high wing, amphibious airplane, was powered by a Continental IO-360, 210 horsepower engine. The pilot held a private pilot certificate with ratings for airplane single-engine land, and airplane single-engine sea. He reported 650 hours of total flight experience on his most recent application for an FAA third-class medical certificate, which was issued on February 28, 2017. The closest weather reporting facility was Auburn/Lewiston Municipal Airport (LEW), Auburn, Maine, about 14 miles east of the accident site. At 1656, weather included wind from 170° at 12 knots; clear skies; visibility 10 statute miles; temperature, 28° C; dew point, 18° C; and an altimeter setting 29.91 inches of mercury.