The Chicago Transit Agency (CTA) will open the Red Line South on 20 October, after a $425m revamp.
The 10.2-mile Red Line South between Cermak-Chinatown and 95th Street has been closed for five months to undergo an upgrade.
The entire railroad was re-laid and eight stations upgraded, creating 1,500 jobs, while the rails, ties, ballast, drainage systems and signaling equipment were all improved to reduce the travel time by 20 minutes.
Built in 1969, the Red Line South had been undergoing repairs regularly, but 40% of it turned into a slow zone resulting in the trains to run at far below their speed limit.
The project, which has been completed on time and within budget, is part of the infrastructure renewal programme known as Building a New Chicago.
The upgrade has been primarily funded from the $646m granted under the Illinois Jobs Now! Programme to CTA, $220m of this has been allocated to the North Side Red Line Branch, Purple Line and Blue Line.
Chicago Governor Pat Quinn said: “The Red Line South reconstruction was among the largest and most important investments in my Illinois Jobs Now! capital construction programme.
“This historic project created more than 1,500 jobs and built a new Red Line that is faster, more efficient and easier to use for tens of thousands of people who will ride on it every day.”
CTA said that 29% of the track work and 40% of station upgrade were awarded to Disadvantage Business Enterprise (DBE) contractors while $56.4m in construction work was awarded to African-American contractors.
The decision to close the line and complete the work in five months saved the agency $75m as against restricting the job to weekends and prolonging it for four years; the saved amount has been reinvested in the development of the eight stations.
Mayor Rahm Emanuel said that the reconstruction of the Red Line South was a historic investment in both the Red Line and the many communities it serves on Chicago’s South Side.
