Well, I am not reading through 843 comments but reaction ferries are prevalent in many places I am sure. I live in British Columbia, Canada where the terrain is mountainous and we have many swiftly flowing rivers. Reaction ferries are to be found on many of them. I have had trips across many of BC's rivers on some of these ferries. As a boy, my father hauled tons of sawlogs from our place over an intervening river to a sawmill with a 5-ton truck. We would be the only vehicle crossing when the truck was full. The pontoons of the ferry would sink quite a ways into the fast flowing current and then we would be off for about a 10 minute ride. Lot's of good memories.