Indiana laws say that no permit is needed to cross streams by loggers or farmers. I however don't like to cross a stream without a bridge or pipe or maybe tree tops to keep the skidder above the water level. They do have a law that anything put into a stream has to be removed when you are done at the site. In flood areas the tree tops have to be moved to high land or secured so they don't float away. They will also allow you to burn the tree tops on site.