SUBJECT ON UNIT 1 WAS CRUISING AT APPROIMATELY 40 MPH. AND CROSSED A WAVE THAT SENT THE SEADOO APPROIXMATELY 3 FEET IN THE AIR. SEADOO CAME DOWN AND SUBJECT WAS SEATED CAUSING LOWER BACK PAIN. SUBJECT WAS UNABLE TO MOVE AND FELL INTO THE WATER. SUBJECT WAS TRANSPORTED BY EMS AND LATER DETERMINED TO HAVE A FRACTURED SPINE.