Benton Street Bridge, Spanning Iowa River at Benton Street, Iowa City, Johnson County, IA

Significance: Crossing the Iowa River in the south-central section of Iowa City, the Benton Street Bridge is an all-welded, continuous, five-span, deck, plate-girder highway bridge. Although all-welded bridges appeared in the United States as early as the 1920s, welding was not widely advocated for new bridge construction until immediately after World War II, when a number of state highway departments began preparing all-welded, deck, plate-girder plans. Designed in 1947 and erected in 1949, the Benton Street Bridge introduced all-welded bridge construction to the State of Iowa, and was nationally recognized as one of the most notable examples of the new genre. An early champion of welding, the bridge's designer, Edward (Ned) L. Ashton, had previously engineered several major Mississippi River crossings, and would subsequently be responsible for the world's first welded aluminum highway bridge, completed in Des Moines, Iowa in 1958. Ashton has justifiably been called "the most distinguished bridge engineer in the history of Iowa."
Survey number: HAER IA-30
Building/structure dates: 1949 Initial Construction
Building/structure dates: 1989 Demolished