I can't think of any examples of successful ferries in North America in places where driving takes more or less the same amount of time as the boat. The most recent and spectacular failure was the Rochester-Toronto ferry, which only lasted a year, despite the enormous investment in the vessel, because it ended up being only slightly faster than driving. The only places where ferries are routinely successful in the US is either where they go where cars can't (i.e. islands) or where they cut a really substantial amount of time off the drive (i.e. Lewes-Cape May or Manitowoc, WI-Ludington, MI).