They didn't seem too surprised that they just passed a floating semi? No "Holy Sh** look at that" it was kind of like "Oh geeze would you look at that, another one of Dale 's delivery trucks went off the I95 bridge....."
Is it up north on something like the MacKenzie River? They drive on the winter ice until (perhaps like this guy found out) it gets thin and they go in. The boaters may not seem surprised because it's been there since the ice melted. Hope the tank is empty and he doesn't get a parking ticket.