Dearborn (Blue Line) Subway Track Renewal
Chicago, Illinois, United States
Client: Chicago Transit Authority
Parsons Brinckerhoff Role: Construction Management
The Dearborn (Blue Line) subway connects the Chicago downtown business district with O’Hare International Airport, serving approximately 150,000 customers daily. As construction manager for this $87.8 million, high-profile track renewal project, Parsons Brinckerhoff helped provide safe and reliable public transportation for the residents of Chicago.
The project, completed in March 2010, involved replacement of wooden half ties with new, cast-in-place concrete half-ties and stone ballast with a new reinforced concrete base slab and direct fixation fasteners. It also included installation of new running rail and new traction power contact (third) rail. One track crossover was completely replaced and a second rebuilt on new ballast. Some structural repairs of the tunnel walls, ceiling and safety footwalks were performed within the 4-mile (6.4-kilometer) length of the 60-year-old tunnel.
To minimize disruption to the thousands of Chicago Transit Authority (CTA) customers during the reconstruction, the majority of the work was performed during weekend 54-hour track outages, during which time one or both of the two tracks were taken out of service. The tracks were then safely returned to full service on Monday morning in time to support the rush-hour commute. The CTA limited the number of outages to 23 and scheduled outages around the city’s summer and fall public events.
The success of the Dearborn Track Renewal Project was critical for the CTA to obtain funding for additional work to bring the system to a state of good repair. The project received an American Council of Engineering Companies (ACEC)-Illinois Honor Award and an ACEC National Honor Award in 2010.