RedactedNarrative: Operator was operating a PWC in Lake Michigan near Calumet Harbor. Operator had borrowed the PWC from a friend and had very little experience with PWC''s. Operator was travelling in a southern direction with the shoreline to his right. As Operator was coming closer to the rock wall near where there were several people in/near the water, he lost control of his PWC and could not avoid a collision with subject.  Subject was in the water hanging on to the wall facing the shore. 
  
  Operator struck subject on her upper back and behind her left shoulder. Operator sustained no injuries nor was his PWC damaged.