The Dearborn–Congress–Kennedy Block 37 project consists of comprehensive train control system and traction power system upgrades along the Chicago Transit Authority (CTA) Blue Line, extending from the Forest Park terminal to Jefferson Park on the O’Hare/Kennedy branch. The project includes the design, fabrication, and installation of new train control and communication
systems, as well as significant modifications to the traction power distribution system and negative return bonding within the Dearborn and State Street subways. Additional scope includes upgrades to architectural, civil, structural, mechanical, HVAC, electrical, and facility furnishings within the project limits.

A major element of the project is the replacement of approximately 20 miles of existing train control infrastructure with a modern, bidirectional cab signal system that is fully compatible with signal systems across the remainder of the CTA rail network. The project also incorporates new interlockings and train control systems to enable future connections between the Dearborn and State subways, following the construction of new tunnels and a station under separate contracts. Collectively, these improvements enhance system reliability, operational flexibility, and long-term transit performance along one of CTA’s most heavily used rail corridors.