These parallel suspension bridges carry I-74 over the Mississippi River between Bettendorf, Iowa and Moline, Illinois.  The northbound bridge was built in 1935 and the southbound bridge was built in 1960.  The bridges are over 3,000 feet long and the longest suspended span is 740 feet.  Our inspection of these structures was limited to an in-depth inspection of the fracture critical members in the deck truss spans and a cursory walk-through of the primary cables.  A corridor study is underway to investigate replacing the structures to provide larger capacity and to meet current day design and safety standards.  The recommended bridge type is a pair of basket-handle true-arch bridges.

As part of the same task work order with the Iowa DOT, we inspected a steel deck truss known as the Kenyon Road Bridge that carries US 20 over the Des Moines River in Fort Dodge.  This bridge is 562 feet long and was built in 1935 and rehabilitated in 1977.  Rope access webbing climbing and a beam roller were used to access this structure.