The last bit of what has been known for four decades as the "Blue Bridge," above, was exploded

The last bit of what has been known for four decades as the "Blue Bridge," above, was exploded Friday afternoon by Dem-Tech of DuBois, Wyo., to remove the steel trusses as work continues on the bridge replacement. Dem-Tech specializes in the precise demolition of structures through the use of explosive technology. At left, Chris Stutz, superintendent of bridge replacement for Great Lakes Construction, and his son Hayden, 2, of Navarre, are all smiles after the bridge goes down. The bridge carries the Madison Avenue Expressway over Salt Springs Road and the MahoningRiver in Youngstown. The blue-colored bridge was built in 1966. Costs to demolish the bridge and replace it have been estimated at $13 million.