US 20 over Iowa R., Iowa Falls, Iowa. County/parish: Hardin.
Added to the National Register of Historic Places May 15, 1998. NRIS 98000518.
Part of Highway Bridges of Iowa MPS (NRIS 64500160).
1 contributing structure.
The Washington Avenue Bridge in Iowa Falls, Iowa, is an attractive concrete, two-span open-spandrel arch bridge that carries Washington Avenue over the Iowa River. Originally, it served as part of U.S. Route 20. The bridge was built in 1934 by the Weldon Brothers at a cost of $51,710.55.
In the 1920s and 1930s, if a relatively long bridge was needed in a rural area, it would typically have been constructed using steel trusses. However, in urban settings—where sufficient height allowed for wide arches—a concrete open-spandrel arch bridge could be built, offering both structural efficiency and visual appeal. In Iowa, other examples of this bridge type include the Mederville Bridge (1918), the Adair Viaduct (1923), and the Iowa Falls Bridge (1928, also built by the Weldon Brothers). The Washington Avenue bridge is especially notable as a well-preserved two-span example.
It was listed on the National Register of Historic Places in 1998.
(read more...)National Park Service documentation: https://catalog.archives.gov/id/75336530