http://www.bbc.co.uk/news/world-us-canada-35420734
Bridge demolished in Pennsylvania
I'm surprised it wasn't cheaper to do it bit by bit? Doesn't that block the river?
I don't believe the river is navigable there, at least not for commercial traffic. I spent a lot of time in that part of Pennsylvania growing up and much of the Allegheny River is pretty shallow.
I really hate it when they demolish these old bridges, though. They are part of the charm of that area and the replacements are always ugly steel and concrete eyesores, which while no doubt cheap, just don't have the personality of an old green truss bridge.
My brother and I used to hike around the mountains out there and run across old railroad truss bridges and abandoned tunnels and oil pumping equipment deep in the woods.