I was able to make an EAST station in my world that connects the dock district to my main market town.
this is just a schematics of the boat station.
read the tips in the schematics if you want to build it in your world.
in the future i'll add corners and a 4 way intersection.
big thanks to Charlie Brown and gjrud for their testing and knowledge

IMPORTANT update
this doesn't work in latest pre release. you'll go in an infinite loop fast movement and you can't get out from the boat.blame mojang for stupid single player multiplayer decision and blame the team again for stupid boat physics