The pilot reported that he taxied the ski-equipped airplane to a snow-covered area adjacent to the runway. He made two passes over 8 inches of fresh snow to create a makeshift runway. He then added engine power and started to take off toward the west. At rotation speed he heard and felt a “whack” along with a “bump,” and deceleration. The airplane felt “mushy” as it became airborne, and the pilot leveled the nose to maintain control. The pilot observed the right ski hanging straight down; with the airplane approaching trees, he pushed the nose down and landed in the remaining open area. The airplane slid about 20 ft before it came to rest; its lower fuselage structure sustained substantial damage. The pilot reported that there were no mechanical failures or malfunctions that would have precluded normal operations. After the accident occurred, the pilot noted that the fresh snow obscured various ice chunks and frozen drifts.