There was an Ampicar tooling around in the Delaware River between New Hope, PA and Lambertville NJ about a month ago. The water level was low due to the drought we've been having, and the car got hung up on a rock. After about a week of trying to get it unstuck, someone finally came up with the idea of putting a large inflatable bag under the car and lifting it up. It worked. I prefer driving on land, where the hazards are visible.