Madison County-McKinley Bridge over the Mississippi River

origins and construction

The McKinley Bridge was constructed in 1910 by the Illinois Traction System, an interurban electric railway that sought to connect Illinois communities with St. Louis. Designed by renowned engineer Ralph Modjeski, the bridge was built as a steel truss structure capable of carrying both rail and vehicular traffic — an innovative dual-purpose design for its time.

Interestingly, the bridge is named not after President William McKinley, but after William B. McKinley, a key figure in the Illinois Traction System who helped bring the project to life.

At the time of its completion, the McKinley Bridge was one of only a few crossings over the Mississippi River in the region, serving as a critical transportation link between St. Louis and Venice.

a role in route 66 and regional growth

With the establishment of the U.S. Highway System in 1926, the McKinley Bridge briefly became part of the legendary Route 66, serving as one of the earliest crossings of the Mississippi River for travelers heading west.

During its early decades, the bridge carried both trains and automobiles, supporting industrial expansion and daily commuting across the river. By 1978, however, rail service on the bridge was discontinued, and it transitioned to exclusively vehicular use.

decline and closure

Like many aging infrastructure systems, the McKinley Bridge fell into disrepair by the late 20th century. A lack of maintenance funding led to deteriorating conditions. By 2001, the bridge was deemed unsafe and closed to all traffic.

restoration and modern use

A major rehabilitation effort began in 2004, led by a partnership between the states of Missouri and Illinois. The project restored the original through truss spans, modernized the approach roadway and added new features to accommodate pedestrians and cyclists.

The bridge reopened to pedestrians and bicycles in November 2007 and fully reopened to vehicular traffic the following month. Today, it carries thousands of vehicles daily while also serving as part of a broader network of trails connecting communities along the Mississippi River.

a bridge for the future

Now more than a century old, the McKinley Bridge continues to serve as both a functional transportation route and a historic landmark. Its integration of vehicle lanes with pedestrian and bicycle paths reflects modern priorities of accessibility and recreation, while its preserved steel truss design honors the engineering achievements of its era.

This study will evaluate and analyze current bridge conditions and traffic management to prepare a report for design approval that justifies proposed preventative maintenance treatments for the structure.  Some of the anticipated treatments include, but are not limited to, expansion joint replacement, bridge deck patching, application of a new bridge deck overlay, cleaning and painting portions of the existing structure steel, and minor structural steel and bridge support repairs.  These treatments are designed to delay the need for more expensive rehabilitation in the future.

As St. Louis continues to evolve, the McKinley Bridge remains a powerful reminder of the city’s industrial roots and its enduring connection across the Mississippi River.

This study will focus on the entire bridge spanning from abutment to abutment on the Illinois and Missouri sides of the bridge.

We are currently nearing the end of Phase I (project study), during which the project team collected data and completed the preliminary analysis of various bridge preservation treatments.

The Illinois Department of Transportation is following the Context Sensitive Solutions process for this study, CSS is an interdisciplinary approach that seeks effective, multimodal transportation solutions by working with stakeholders to develop, build and maintain cost-effective transportation facilities that fit into and reflect the project’s surroundings, its “context.” 

Your input and feedback are critical to the success of this project, and your participation in the process is welcomed.  Here are some ways you can participate and stay informed and engaged:

• Attend public meetings and open houses
• Sign up to receive our project newsletter
• Take our online surveys
• Provide feedback and submit comments
• Share information with your neighbors and friends

A Stakeholder Involvement Plan has been developed to outline the opportunities and timeline for outreach activities. A copy of this plan is available upon request.

News and Events

Q. What is the purpose of this project?
A. This is a bridge preservation project aimed at maintaining the existing condition of the bridge and extending its service life. The work is intended to delay the need for more extensive and costly rehabilitation in the future.

Q. What improvements will be made?
A. Planned improvements include bridge deck patching, replacement of expansion joints and the application of a new deck overlay to the driving surface. The project will also incorporate minor structural repairs, along with cleaning and painting of select bridge components.

Q. Will the proposed improvement affect any of the historical elements or characteristics of the bridge structure?
A. Minimal impacts are anticipated to the historical elements or characteristics of the bridge structure.

Q. Are improvements planned for the bike lane on the bridge?
A. At this time, it is anticipated that the new bridge deck overlay will be restricted to the driving lanes and adjacent shoulders.

Q. Will there be any traffic impacts?
A. Yes. The bridge is anticipated to be fully closed to vehicle, pedestrian, and bicycle traffic during construction.

Q. When will construction start and how long will it last?
A. Construction is currently anticipated to begin in early spring 2028 and continue through the full construction season, with completion expected in fall 2028.

Q. How can I get involved and stay informed?
A. Please visit this project website regularly for updates. To receive the project newsletter and public meeting announcements, please contact Brandon Humphreys at (618) 346-3413 or by email at brandon.humphreys@illinois.gov. 

Submit comments to:

Illinois Department of Transportation – District 8/Region 5
c/o   Brandon Humphreys, Civil Engineer IV
1102 Eastport Plaza Drive
Collinsville, IL 62234
Phone: (618) 346-3413
E-mail: brandon.humphreys@illinois.gov