On March 15, 1998, at 2000 central standard time, a Cessna 310Q, N1521T, operated by a private pilot collided with a snowbank while landing on runway 13 (4,100' x 75') at the Council Bluffs Municipal Airport, Council Bluffs, Iowa. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions on an IFR flight plan. The airplane was substantially damaged. The pilot and two passengers were not injured. Two other passengers received minor injuries. The flight originated from North Platte, Nebraska, at 1830 cst. The pilot reported he flew the VOR-A approach, cancelled IFR and made a visual approach to landing on runway 13. The pilot reported he extended the landing gear and 15 degrees of flaps during the approach, but he was unable to extend the wing mounted landing lights. He stated the runway lights were at "maximum brightness" and the visibility was "good." The pilot continued to report, "...I was aligned between the runway lights. I was descending gently, feeling for the last few feet of altitude. Several hundred feet down the runway, the airplane impacted a snowbank along the right (west) side of the runway. The snowdrift was inside the runway lights, and extended several feet onto the 75 foot runway." The nose gear collapsed and the airplane slid sideways coming to rest on an easterly heading. The Council Bluffs Airport manager arrived at the airport shortly after the accident occurred. He reported, "The aircraft appeared to have settled in on top of a snow bank parallel to the runway. The nose gear made contact on top of the snow bank then the right main, then the left main. The nose gear collapsed from engaging the snow bank causing the left tip tank to impact the runway, then the left propeller, then the right propeller." He reported during a telephone interview that the tracks in the snow indicated that the airplane did not veer off the side of the runway, but rather the initial touchdown was in the snow off the side of the runway. During a telephone interview the pilot stated the airplane touched down about 1,000 feet down the runway at an airspeed of about 100 mph. The pilot reported that the nose gear collapsed immediately upon touchdown. He continued to report that the left propeller was heavly damaged and although the right propeller was also damaged, it was not damaged to extent of the left one. He stated that after he looked at the damage it made sense to him that the right propeller was in the snow when the nose gear collapsed. He also stated that after reviewing the aircraft manuals he determined that he was unable to extend the airplane's landing lights because he was moving the switch in the wrong direction.