Sec. 7. A personal watercraft shall not be used on public waters to tow individuals engaged in waterskiing, aquaplaning, or similar activities, unless:
(1) the personal watercraft is at least nine (9) feet long;
(2) the personal watercraft is designed to seat at least three (3) individuals;
(3) an individual other than the operator of the personal watercraft is aboard the personal watercraft, acting as an observer; and
(4) the total number of persons on the watercraft and being towed is not more than the capacity of the watercraft.