The pilot was en-route when he decided to land the helicopter in a clearing, near the edge of a small dam. The wind was from the north-east and gusting to about 25 knots. Temperature was about 25 degrees Celsius. As the aircraft was about to enter a hover the pilot noticed that the ground near the edge of the dam had too much slope to permit a landing into wind. He turned the aircraft slightly downwind so that the tail would be facing down the slope. At a height of about 15 feet the low RPM warning horn sounded. The pilot attempted to reject the landing. He applied power, at the same time lowering the collective slightly and moving the cyclic forward to gain speed. The helicopter had insufficient forward speed or height to recover and landed in scrub, skids level, about 200 feet beyond the dam. It bounced twice, rolling onto its side after the second impact, severing the tail cone and destroying the main rotor blades.