On March 26, 1999, about 1530 central standard time, a Cessna 172, N8968B, collided with trees while maneuvering for an emergency landing at Florala Municipal Airport, in Florala, Alabama. The airplane was operated by the private pilot under the provisions of Title 14 CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed at the accident site and no flight plan was filed. The pilot received minor injuries and the airplane sustained substantial damage. The personal flight originated from Florala, Alabama at 1527. According to the pilot, the airplane had been parked on the ramp for several days, and it had rained the day before the accident. During the preflight inspection the pilot stated he had taken fuel samples from both fuel tanks and found no water or other contamination. After the preflight examination, the flight departed on runway 04. The pilot turned downwind, and had started a turn to left base when the engine lost power and sputtered. The pilot activated the carburetor heat and switched fuel tanks before returning the fuel selector to both. The engine continued to sputter. While attempting to return to runway 04, the airplane collided with trees approximately 50 feet south of the airport. Examination of the airplane disclosed that a quantity of water was in the fuel tanks. The pilot did not report or experience a loss of engine power until he started a left descending turn for the base leg of the traffic pattern.