RedactedNarrative: UNIT 1 WAS BACKING OUT OF DOCKING AREA AT KEOWEE MARINA AND THEN CHANGED DIRECTION TO FORWARD WHEN THE OPERATOR STATED HE GAVE TOO MUCH THROTTLE.  UNIT 1 STRUCK UNIT 2 WHICH WAS TIED TO THE DOCK.  UNIT 2 SUSTAINED A PUNCTURE TO THE PORT FIBERGLASS AND SCRATCHES.