Nope, if a tile isn't passable, no events can move over it (including the hero event) except for explicit cases such as being passable by airships. And if it IS passable, everything can move on it (including the hero event, again.) This leads to situations where the hero can walk on water - the usual workaround is a blank event that is set to "Same Layer As Hero" which acts as a border around the part of the map that you want to block access to.


I'm not sure what you want to do with boarding the boat - you can force that with "Enter/Exit Vehicle" if you move your hero to it (either manually or with events).