Gillespie Ave. / Clinton River

MDOT Historic Bridge Oakland County Gillespie Ave. / Clinton River

County: Oakland

City/Township: Pontiac

Location: Gillespie Ave. / Clinton River

Year Built: 1936

About this Bridge:
The Gillespie Street Bridge, built in 1936, is a relatively early example of rigid-frame construction in Michigan. Wayne County introduced rigid-frame bridges in the state in the early 1930s, and the Michigan State Highway Department adopted the design in 1935-1936. While the style was popular into the 1950s, few well-preserved structures of this type remain. The Gillespie Street Bridge is eligible for the National Register as an excellent example of concrete rigid-frame design.

The bridge was designed for the city of Pontiac by Harold Hawley Corson, a consulting engineer. Born in nearby Birmingham in 1886, Corson received a civil engineering degree from the University of Michigan. He worked on the construction of the Detroit River Tunnel and was briefly employed by the U.S. Reclamation Service. From 1922 to 1927, he apparently did some consulting work for the Michigan State Highway Department. He returned to Birmingham in 1927, where he served as the town's engineer until at least the 1940s. It was during this period that he prepared the plans for the Gillespie Street Bridge for the city of Pontiac.

It is unclear why Corson selected a rigid-frame design for the Gillespie Street crossing. Rigid-frame bridges had initially appeared in Michigan in the early 1930s, and he perhaps sought to experiment with this new bridge type at a modest scale. The first concrete rigid-frame bridge in the United States was built in Westchester County, New York, in 1922. The design was considered both attractive and practical: it offered a broad, arch-like opening with a relatively shallow superstructure and a minimal loss of headroom beneath the span.