RedactedNarrative: On July 23, 2015 at 14:30 hours at Lake Quivira, located within Lake Quivira, Kansas, vessel 1 was towing a tube with two occupants on it.  The operator of vessel 1 stopped in the middle of the main body of the lake.  When the two occupants on the tube signaled that they were ready to be pulled, operator of vessel 1 increased the throttle of the vessel to take off.  The back of the tube was facing the stern of vessel.  As the slack in the tow line became taut, it came out of the water and over the tube and across the knee of victim 1 and caused a deep laceration.  At that same time the metal cable tow harness of vessel 1 snapped.  Operater 1 took victim 1 and occupant 1 to the beach for medical aid.  Operator 1 called Emergency Medical Services to respond.  Emergency Medical Services transported victim 1 by ambulance to the Shawnee Mission Hospital in Shawnee, Kansas.  When vessel 1 was inspected by law enforcement, a mirror was located on the control panel of it.