Chicago Transit Authority EV Charging Infrastructure

Mortenson and Proterra were chosen as the team for Chicago Transit Authority’s (CTA) first foray into electrification. This design-build project included engineering, procurement, and construction of eight rapid-charging electric bus overhead opportunity chargers at three locations along Chicago Avenue in Chicago, Illinois. These stations were: Navy Pier, a heavily trafficked tourist area; the Chicago Garage, a central operations and maintenance depot; and the Chicago / Austin Avenue turn around, an existing, limited-service bus stop in an economically challenged area of the metro.

The overhead, cantilever-type chargers allow buses to “reload” while on route so the vehicles can return to service quickly. The project supported up to 40 Proterra all-electric buses on Chicago Transit Authority’s Route 66.

To support the overhead rapid charging systems installed at the Navy Pier and Chicago / Austin Avenue Bus Turn Arounds (BTA's), Mortenson constructed two electrical buildings. These glazed brick masonry structures house the 600 VDC charging systems, AC switchgear, and HVAC equipment. Both BTA's included new site utilities and dual AC service provided by ComEd.

The project also included the installation of electrical equipment at the Chicago Garage including an overhead pantograph system and depot charging system and depot charging system.

The CTA EV Charging Infrastructure project was CTA’s first big step in achieving their goal of converting their entire bus fleet to electric, including facilities and supporting infrastructure, by 2040, making it one of the first large cities in the United States to take on such a large and complex electrification project.

Due to the Navy Pier location being considered a "Superfund Act" site by the Environmental Protection Agency, the scope of work also included the remediation of thorium from the project site.

For this project, Mortenson prioritized the customer's goal of achieving a 30% Disadvantaged Business Enterprise (DBE) utilization. Through our dedicated efforts and strategic partnerships, we surpassed this target, achieving 43% DBE utilization by the project's completion. This accomplishment underscores our unwavering dedication to fostering diversity and inclusion within the industry.