According to the pilot, he noted the tarmac and runway were covered in a half inch of rough ice during preflight. He back-taxied on the runway and performed a normal run-up without any problems. During the departure roll the aircraft veered toward the left, departed the runway, and came to rest in a creek. Examination of the airplane revealed the left aileron was damaged. The pilot and passenger were not injured. The pilot reported no mechanical anomalies prior to the accident. Wind conditions reported five minutes before the accident were 260 degrees at 16 mph gusting to 21 mph.