This week’s Pic of the Week provides us with a rare example of a historic bridge that is homemade- built by bridge companies that are local with a local engineer overseeing the design and construction. This bridge is located in Linn County, spanning the Iowa River. The Greencastle Avenue Bridge is located NW of Cedar Rapids in the Hawkeye Wildlife Area. It features a pin-connected Pratt pony truss span and a riveted Pratt through truss span with A-frame portals. Originally built as a three-span bridge in 1922, one of the spans was destroyed in the flooding in 1949 and was replaced with a temporary span in 1950. That span was then removed and filled in, reducing the crossing to only two spans. The bridge has been abandoned since 1992 though one can access the bridge by car from the north side but going down a steep hill. At the entrance to the bridge on the north side, it is all for pedestrians.
The bridge is unique as it was built and rebuilt by four different bridge builders, all of which were located in Iowa. Two of them came from the same county as where this bridge is located- Linn County. The pony truss span was built by the Iowa Bridge Company of Des Moines; the through truss span was a standardized bridge built by the Iowa State Highway Commission of Ames. For the reconstruction of the bridge after the flood of 1949, there were two local bridge engineers responsible: Ned L. Ashton of Iowa City and A.P. Munson of Marion. Ashton was well known for bridges during his time, for each of the Cedar River crossings in Cedar Rapids and Iowa City that exist today were either built by him or whose predecessor spans had been built by him but were replaced in the end. The crossing is the second one in its present location as a previous structure, a through truss span, was built by another Iowa bridge firm, J.E. Jayne and Sons, located in Iowa City. That bridge, known by locals as the Dupont Mill Bridge, was built in 1908 and replaced in 1922. All in all, there were five different bridge builders all in this location, three of which in Linn County! Amazing how such a bridge could have the markings left by locals.
The bridge is not on the National Register but should because of its history, including what was mentioned already. The structure is still in place but is in need of a full restoration in order for it to continue its life as a pedestrian crossing. Given its location and setting, it would be perfect except to say, one could make a picnic area out of it, with info boards on its history and that of the adjacent Dupont Mill. Whether it will happen depends on the interest and there seems to be a lot of interest in keeping the bridge and reusing it. The question is whether Iowa Department of Natural Resources and Linn County would agree. But given the county’s high number of historic bridges and the way they have been maintained, there is a chance that the officials will listen and make the proper maintenance of and repairs to ensure the bridge will continue its use for years to come.
Iowa is celebrating 175 years this year and if there is a piece of history that should be considered, it’s this bridge. While the state has seen the likes of King, Jensen, Thacher, Wickes, and Jayne in several of the bridges, there are some that deserve recognition for their work, like Ashton and Munson. And this bridge represents such a structural work that deserves attention from these people.