I was always told that the rule in Mo, or at least on the Missouri river, is public property stops at the high water mark, which is usually the vegetation line at the tops of the banks. I know of a few guys who have had charges pressed against them for mushroom hunting along the banks of the river. I don't know if flooded conditions affect this rule or not, but I would think if you pay taxes on the ground then it is private, regardless of if there is water covering it or not. I would guess a wildlife official would answer your question in due time, but sometimes it takes a few days or even a few weeks for them to respond here because first of all they are busy guys with a lot of ground to cover and second your question is gonna be a little tough to get a definative answer (as to whats legal and how to enforce it). it seems like when a tough question is asked, our agents like to ask other agents their opinions so you get an accurate answer.