Gateway Bridge

Information and Findings From Iowa's Historic Bridge Inventory

Discussion of Bridge

In 1944 an act of the U.S. Congress authorized the organization of the City of Clinton Bridge Commission to supervise the planning, financing and construction of a new bridge across the Mississippi. The first meeting of the seven-man board was held on April 5, 1945 (Clinton Herald, June 29, 1956:20). Traffic counts and surveys were conducted in 1945, 1946, and 1953 to gather information in support of the financing and potential location of the new bridge (Clinton Herald, June 29, 1956:29). The ISHC contracted Modjeski and Masters of Mechanicsburg, Pennsylavnia to design the bridge. Plans were drawn up in 1951 and finalized in January 1954. Work on the bridge began on September 21, 1954. Allied Structural Steel Companies of Clinton provided the steel for the bridge. The bridge was completed on June 30, 1956. The total cost of the bridge was $6.8 million (City of Clinton Bridge Commission 1956:2). In 1976, repairs were made to the west abutment and four piers on the west side of the bridge.

The bridge was included in the Phase II survey as it is a large of exceptional span or overall length, which according to the registration requirements in the MPD includes any steel suspension bridge. The steel suspension bridge is the only one of its type (Type 313) built in the state. As such, the U.S. 30 Mississippi River Bridge is eligible for inclusion in the NRHP under Criterion C as it does meet several registration requirements outlined in the MPD for bridges under Criterion C as a large exceptional span, as an exceptional example of work by an important engineer such as Modjeski and Masters; and under Criterion A as a bridge that was built as part of a large bridge building initiative.

Spans: The crossing has 15 approach spans on the west side (6 beam spans and 9 girder spans) and 14 approach spans in the east side, all of which are girder spans.

Bridge Considered Historic By Survey: Yes