I-535 Blatnik Bridge

Duluth, Minn., and Superior, Wis.

About this project

A rendering of the Blatnik Bridge location.

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The John A. Blatnik Bridge, one of two bridges that connects Duluth, Minn., to Superior, Wis., opened to traffic in 1961 and carries I-535 over the St. Louis Bay. The Blatnik Bridge is an important freight and commercial connection between the Twin Ports.

Jointly owned and managed by MnDOT and WisDOT, it is Minnesota's second longest bridge and serves an average of 33,000 cars traveling between the two cities each day. In early 2024, the two agencies received more than $1 billion in federal funding to replace the aging bridge. Both states are also contributing funding for the project. MnDOT will lead the bridge replacement project, which will address aging infrastructure, improve safety and better accommodate oversize/overweight loads.

New bridge alignment

A rendering of the chosen Blatnik Bridge alignment.

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After more than three years of studying multiple alternatives and engaging the public for feedback, the states will construct the new bridge on the same alignment as it exists today. It will also include a shared-use path, and a new interchange into Superior will be constructed.

Since project development began in 2020, many alternatives were considered against the project purpose and need and evaluation criteria. The process was broken into several steps and documented in technical reports available in Appendix F of the Environment Assessment document on the project website to allow for public and agency input at key decision points.

Reasons for keeping the bridge on the current alignment include

  • Provides shortest overall construction duration
  • Eliminates risk of construction near motorists
  • Minimizes impacts to properties and wetlands
  • Lowest cost option

Find out more on the Documents page or the Meetings page.

History and future of Blatnik Bridge

WisDOT created a video sharing the history and future of the Blatnik Bridge.

Federal INFRA grant

MnDOT and WisDOT received word Monday, Jan. 22, that the two states received more than $1 billion in the form of the federal INFRA grant to replace the Blatnik Bridge. Since then, the Department of Transportation has released a new video talking about Blatnik Bridge and how President Biden’s Bipartisan Infrastructure Law (BIL) is creating jobs, improving lives and creating stronger communities.