LAUNCHED DRIFT BOAT.  WAS ROWING WHEN OPERATOR SAW OBSTRUCTION (TREE).  THE OPERATOR FAILED TO NEGOTIATE THE DRIFT BOAT AROUND THE MID-STREAM OBSTRUCTION AND FLIPPED THE BOAT.  THE PASSENGER FLUSHED OUT AROUND THE OBSTRUCTION AND THE OPERATOR SWEPT UNDER THE OBSTRUCTION.  A COMMERCIAL BOAT PASSING BY CALLED 911.  THE BOATERS WERE PICKED UP BY RANGERS.
MOOSE                         