Dunnet Bay Construction

Dunnet Bay Construction is an Illinois heavy-civil contractor that builds the roads, bridges and interchanges most drivers never think about. Based in the Chicago suburbs, the firm specializes in complex highway work for state and tollway agencies, the kind of job that closes lanes for years and reshapes a corridor. Dunnet Bay is the prime contractor on the western interchange package of the new I-490 Tollway near O’Hare, a tri-level connection carrying millions in roadway and bridge work. It’s the sort of self-perform heavy-civil outfit that state DOTs and the Illinois Tollway lean on for their largest, most technical projects.

Dunnet Bay Construction Company has operated out of Glendale Heights, Illinois since 1990, and the firm frames its history around a straightforward claim: over three decades of tackling difficult heavy-highway work across Chicagoland. A second office in Hammond, Indiana extends that footprint into northwest Indiana, giving the company two operating divisions under one roof.

The company organizes its work into four divisions: airports, rail, road and bridge, and foundations. That structure reflects a business built around self-performing the bulk of its own scopes rather than subcontracting them out. Dunnet Bay maintains a 100%-owned equipment fleet, which it says gives more control over schedule, quality and cost on infrastructure jobs.

Its client list points to the kind of agencies that define heavy-civil work in the region: the Illinois Department of Transportation, the Illinois State Toll Highway Authority, the Chicago Transit Authority, Metra, the Chicago Department of Aviation, Union Pacific and the Indiana Department of Transportation, among others named on the company’s site.

Recent recognition from public agencies backs up that track record. IDOT named Dunnet Bay its 2024 Bridge Rehab Contractor of the Year and its 2023 Contractor of the Year, and the Illinois State Toll Highway Authority named the company its 2022 Bridge Contractor of the Year, three awards across three consecutive years and two different state agencies, both listed on the company’s homepage.

The foundations and earth-retention expertise the company built serving public agencies has also become a doorway into private-sector work, according to Dunnet Bay’s own description of its growth. For a company whose roots are in heavy/highway construction management, that marks a notable expansion beyond the traditional DOT-contractor model.

Contact for the Illinois headquarters runs through the Glendale Heights office at (630) 539-1200, while the Indiana division can be reached at (219) 844-9522.