Minnesota and Wisconsin Advance Design-Build Selection for $1.8B Twin Ports Bridge Project

Minnesota and Wisconsin transportation agencies have narrowed bidders for a $1.8 billion effort to replace the aging John A. Blatnik Bridge linking Duluth and Superior.

The 7,975-foot structure, opened in 1961, connects Interstate 535 across the St. Louis Bay and carries about 33,000 vehicles daily. Deterioration forced weight limits in 2019, prompting a full replacement plan led by MnDOT.

Two contractor teams—Ames Kramer Joint Venture II and Lunda Construction—remain in competition for the design-build contract. The future bridge will follow the existing alignment and may adopt a cable-stayed or tied-arch design.

The project received $1.06 billion in federal support through the Infrastructure Investment and Jobs Act’s MEGA and INFRA programs. Minnesota and Wisconsin will each fund $400 million in additional costs.

Pre-construction and permitting will continue into 2026, with major work expected to begin later that year and extend through 2031. The new bridge will have a projected 100-year lifespan.