CDOT Lake Street Bascule Bridge Proposal Design

The Lake Street Bascule Bridge is one of Chicago’s most recognizable double-decker bridges carrying both vehicles and CTA trains across the South Branch of the Chicago River. Our proposal focused on preserving this 1916 landmark while planning a major structural rehabilitation to extend its life for another century.

Rehabilitating a movable bridge with an active CTA line running above it required extreme precision. The team had to plan two 12-day full outages to replace truss spans, coordinate with multiple agencies, and protect the bridge’s historic architectural houses—all while keeping traffic, river navigation, and daily city life moving.

To help tell the story visually, I created a custom illustration of the Lake Street Bridge, showing how the team would manage the complex “float-in” outages—where massive truss spans are floated in and out by barge. This graphic became a centerpiece of the proposal, simplifying a highly technical process for reviewers.

Working closely with the project manager and engineers, I built layouts that highlighted each stage—from demolition and lift coordination to balancing and realignment. The visuals paired with clear callouts and captions to show how the team would maintain CTA service, protect the structure, and preserve its historic character.

The final proposal delivered a clear, engaging narrative combining technical depth with strong visuals. The custom illustration made the approach instantly understandable, helping communicate how HNTB’s “Movable Bridge A-Team” could confidently deliver one of Chicago’s most complex bridge projects on schedule and with minimal disruption.