Newly Reconstructed Merchants Bridge Opens in St. Louis

Float-in of the third and final truss for the reconstructed Merchants Bridge in St. Louis. Photo courtesy of Walsh Construction and Trey Cambern Photography

Merchants Bridge in St. Louis reopened to rail traffic last week, marking the completion of a decade-long, $222 million reconstruction of the vital rail artery connecting Missouri and Illinois.

As one of the most heavily traveled crossings over the Mississippi River, Merchants Bridge links the eastern and western rail networks in the United States, providing an alternative to more congested rail hubs like Chicago. The 133-year-old bridge required reconstruction due to speed, clearance, and load restrictions.

In addition to addressing these areas, the newly reopened bridge boasts a double track, providing reliable, resilient, and expanded freight and passenger rail capacity. In fact, bridge owner Terminal Railroad Association of St. Louis estimated that the bridge renovation will generate more than $456 million of economic activity over a 20-year period for the region.

To ensure minimal disruptions to rail service during construction, the project team constructed all three new spans for the bridge at AISC member fabricator Veritas Steel in Wisconsin and shipped them to St. Louis for final assembly. Immediately after floating the old spans out, workers floated in the new spans, with the final truss installed on August 27.

Joining Veritas Steel as part of the project team for the Merchants Bridge replacement are project engineers TranSystems and Burns & McDonnell, as well as general contractor Walsh Construction.