RedactedNarrative: UNIT 1 WAS TRAVELING WESTBOUND ON CASTLE ROCK LAKE APPROXIMATELY 100 YARDS OFF THE SOUTH SHORE. UNIT 1 WAS TRAVELING AT APPROXIMATELY 10-15 MPH. UNIT 1 STRUCK AN UNDERWATER SAND BAR WITH THE LOWER UNIT OF THE MOTOR. THE DRIVER WAS UNINJURED. THE PASSENGER WAS THROWN FORWARD FROM HER SEAT WENT HEAD FIRST INTO THE SEAT IN FRONT OF HER CAUSING A NECK INJURY. OPERATOR OF UNIT 1 CALLED 911 FOR AN AMBULANCE AND THEN DROVE THE BOAT BACK TO THE LAUNCH AT CASTLE ROCK COUNTY PARK WHERE EMS MET WITH THEM. PASSENGER WAS TRANSPORTED BY MAUSTON AREA AMBULANCE TO MILE BLUFF MEDICAL CENTER. INSPECTION OF BOAT DID NOT SHOW ANY NEW DAMAGE.