Is it legal to fish a moving body of water such as a creek or river on private property as long as you are on the water and do not step out on the bank and access it on public ground?
Only if it is considered a navigable waterway by the army corps of engineers. And then you still cannot touch the stream bottom. I've researched this myself due to some trespassing issues in the past. There's a website somewhere that actually list the navigable streams in the state.
It is impossible to answer that as there are so many variables. If you aren't on a Corps of Engineer's listed navigatable water, and are talking about wading, my best guess is that it would not be legal without the landowner's permission.