You ought to try entering the ocean, swamp, river, or whatever at your own risk if the Coast Guard is around. You will be required to at least have a pfd on board for everyone in the boat. Once. while I was out sailing in my 30 ft. sailboat, a Coast Guard Boat came by and told me to sit down in the seat and put my life vest on. I almost gave him the one finger salute, but I thought better of it and just sailed away.
Anyway, entering the forest, ocean, or any other general area is different than a designated camp spot. I'm not into petty litigation at all, but there is the law of reasonable expectations.