Rail Bridge Replacement Marks Major Milestone for Wisconsin’s Oldest Interchange

Wauwatosa, WI — Built in 1963, the Zoo Interchange stands as Wisconsin’s oldest and busiest interchange, connecting Interstates 41, 94, and 894 near the Milwaukee County Zoo. The Wisconsin Department of Transportation (WisDOT) and Federal Highway Administration (FHWA) began reconstructing the Zoo Interchange in 2013 to improve safety, reduce congestion, replace aging infrastructure and improve vertical clearance at bridges. Following a successful collaboration between WisDOT and FHWA, the community came together to celebrate completion of the North Leg of the Interchange during a ribbon cutting ceremony.

The North Leg Project was the final segment to complete the Zoo Interchange and included expanding a 1.7-mile segment of I-41 from six lanes to eight; widening the on and off ramps; and constructing frontage roads, cut walls, retaining walls and noise walls. The project also involved replacing several freeway bridges, as well as reconstruction of a Union Pacific Railroad (UPRR) bridge passing over the interstate.

Benesch oversaw the design and construction of the temporary and permanent UPPR bridge structures for the North Leg Project. The replacement railroad bridge structure consists of a two-span through plate girder superstructure supported by concrete substructures in-line with the existing I-41 underpass.

“The railroad structures involved in this project were highly complex,” said Benesch Project Manager Jordan Card, PE, SE. “Due to the straight alignment of the UPPR rail track, designing an off-alignment bridge was not possible. Instead, a temporary roll beam bridge was constructed about 40 feet west of the existing one to keep trains moving safely through the area as the new bridge was constructed on the existing alignment.”

Benesch’s railroad team regularly works with UPRR on complex projects like this which require partnership between DOTs and railroads. On behalf of the railroad, Jordan oversaw all aspects of the peer reviews, construction observation and steel superstructure shop inspections. Additionally, he was responsible for managing the schedule, budget and communication involved in construction of the new railroad bridge.

“It’s always exciting to see projects like this come to successful completion,” said Jordan. “Especially when rail bridge construction overlaps with highway work, there are so many moving parts to keep track of. Overseeing this kind of work is something our team excels at—it’s a pleasure to work with UPRR in this capacity.”

After nearly three years, the North Leg of the Zoo Interchange was successfully completed, and the interstate was reopened to traffic on November 6. On November 9, Jordan joined officials in Wauwatosa for a ribbon cutting ceremony to mark the completion of the project.