Can't you just drag it a few feet out of the water at the bank near the campsite? Would be technically out of the water if its not floating... If that's not enough to satisfy them and your site is near the waters edge then have You got a winch on your truck? Setup camp near the waters edge and Face the water with it and yank it up a bit further if you cant pull it, if no winch then take a bit if extra rope and park backwards and use the trailer winch to pull it out. Use some round logs under it like rollers and tie it off if you think you can't push it back in..
edit - scratch all that, just read you can't even pull them up any bank.