SQN provided construction management services for CTA’s Blue Line Train Control and Communication System Upgrade project, improving safety, reliability, and operational performance along the O’Hare Branch. The project included installation of new train control and communication systems between Jefferson Park Interlocking and O’Hare Interlocking, track replacement within the O’Hare subway/tunnel approach, signal upgrades, and related civil, structural, and mechanical work. The improvements eliminated longstanding slow zones and enhanced service reliability along the corridor.
Sine Qua Non | Absolutely Essential