MnDOT Twin Ports Interchange CM/GC


Twin Ports is Minnesota’s largest progressively developed CM/GC project. With a multi-year timeline with multiple work packages, Twin Ports is the reconstruction of the I-35/I-535, Hwy 53 Interchange in the heart of Duluth, MN, adjacent to St. Louis Bay. The project includes complex traffic management and innovative phasing to eliminate blind merges and left exits and improve freight movement on the aging interchange known as the “Can of Worms.” The project provides motorists improved merging sight distances while eliminating merge conflicts while providing lane continuity for through I-35 traffic. The project significantly reduces the number of load-restricted bridges while using innovative ground improvement techniques to build the interstate on an elevated fill section. The project features constrained right-of-way corridors, multiple rail crossings, and 18 bridges. The Kraemer team maximized winter work, such as bridge removal, pile driving and construction of the substructure and Miller Creek box culvert so earth work, concrete pours and paving could start in the summer months. The project also required management and treatment of contaminated soils and groundwater. The Kraemer project team worked with MnDOT, local agencies, Western Lake Superior Sanity District, and vendors to implement a response action plan. Kraemer assisted in the development of project specifications and work plans that significantly reduced schedule, cost, and risks to the project. The project, initiated in 2020, is scheduled for completion in 2025.