RedactedNarrative: UNIT 1 WAS OPERATING ON CASTLE ROCK LAKE HEADING TOWARDS THE BRIDGE ON CTH Z ON THE ADAMS COUNTY SHORELINE. OPERATOR OF UNIT 1 STATED THE THROTTLE STUCK AND HE WAS UNABLE TO SLOW DOWN. OPERATOR TOLD PASSENGERS TO JUMP OFF AS THEY WERE HEADING TOWARDS THE ROCK SHORELINE JUST NORTH OF THE BRIDGE. ALL OCCUPANTS JUMPED OFF THE PWC AND THE PWC CONTINUED INTO THE ROCKS CAUSING THE DAMAGE. PWC PARTIALLY SUNK AND WAS TOWED TO THE NEAREST LAUNCH BY A PASSERBY WHO ALSO TRANSPORTED THE OCCUPANTS OF THE PWC.