The pilot reported that as he made a teardrop turn towards the airport, the engine lost power. Shortly thereafter, it resumed developing power. The engine lost power and resumed developing power on two more occasions. The engine lost power a fourth time but did not regain power. The pilot switched the fuel selector from both tanks to one tank, and turned on the backup ignition. The engine would not resume operation. The pilot realized he did not have enough airspeed or altitude to glide to the runway so elected to make a forced landing on a narrow gravel road. As he approached the road, the left wing struck the top of a tree, spinning the airplane around. The pilot said the airplane made a hard impact with the ground. The left wing leading edge sustained compression damage, and the main landing gear was spread apart. Post-accident examination revealed water in the fuel. The carburetor was opened and a “substantial” amount of water was drained. Water was also found in the pilot's fuel storage tank. The pilot surmised that the water was likely due to recent heavy rain showers. The pilot admitted he failed to check the fuel when he preflighted the airplane, and he overlooked checking the fuel storage tank’s fuel filter/water separator.