Very interesting map indeed. Quite creative and unusual location for a settlement, not to speak of the harbor. I am curious as to how ships would enter the docks? Perhaps a giant winch of some kind could pull a ship up the rails. Also, I do agree with Arimel, the current would be dramatic, so the rails probably need to be extended to cover the entire precipice of the waterfall to act like a funnel, or a ship might be pushed over the edge of the fall before it can properly align.
Besides that, a very cool and fantastical map.