Chicago spent seven years rebuilding two miles of elevated railroad without shutting it down. On July 1 the job hit substantial completion.
The Walsh-Fluor Design-Build Team, with Stantec leading design, delivered Red and Purple Modernization Phase One for the Chicago Transit Authority. At $2.1 billion, it’s the largest capital project CTA has ever finished.
Rebuilding a century-old elevated structure in service
The corridor between Lawrence and Bryn Mawr carried steel that went up around 1920. Crews replaced just over two miles of it and rebuilt four stations — Lawrence, Argyle, Berwyn and Bryn Mawr — as fully accessible facilities. All four opened to riders in summer 2025.
Trains never stopped running. Anyone who has staged a phased demolition over an operating right-of-way knows what that constraint does to sequencing, and to price.
The Belmont bypass is the part that adds capacity
New stations are what riders notice. The flyover at Belmont is what actually changes the railroad.
Brown Line trains used to cross the Red and Purple mainline at grade. Every crossing move made trains from three lines wait on each other, and it hard-capped how many Red Line trains CTA could push north of Belmont no matter what demand did. The bypass carries the Brown Line over the top. The conflict is gone.
Crews also laid 11 miles of new digital track-circuit signaling, which adds throughput now and clears the path for future signal and rolling-stock work.
What it cost and what it proves
Funding came through a $957 million Core Capacity Full Funding Grant Agreement from the FTA, signed in January 2017, plus a dedicated Transit TIF from the city. It’s one of the largest Core Capacity awards the program has issued.
Design-build got a hard test here: a fixed corridor, a live railroad, a 100-year-old structure with unknown conditions, and a federal funding agreement with teeth. Final completion is scheduled for November 2026. Full details are on our RPM Phase One project listing, and CTA’s program page has the segment-level detail.
The next question for Chicago is whether CTA runs the service the bypass now permits. Steel doesn’t move people. Timetables do.