Interstate 90 - Exit 406 (Brandon)

Project Summary:

This project includes the reconstruction of exit 406 (Brandon) with added lighting, signals, and mainline Interstate work. This project also includes three structure replacements. 

  • The interchange will be reconstructed as a diverging diamond configuration.
  • Westbound Interstate 90 lanes (along with the railroad structure on I90) will be reconstructed in 2024 and the eastbound lanes (and railroad structure in 2025). The interchange itself and new structure over I90 will be reconstructed between 2024 and 2025.
  • S.D. Highway 11 traffic will be maintained across Interstate 90 during construction.
  • The westbound on-ramp and eastbound off-ramp are expected to be open to traffic for the majority of the project. Closures for the westbound off-ramp and eastbound on-ramp are planned for 2025.
  • Work will extend on S.D. Highway 11 down to Redwood Boulevard. That work includes adding a shared use path on the west side, approach and side street work, a retaining wall on the east side north of Ash St, and other items.

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Text "I90Exit406" to 605-566-4041

Project Timeline:

Spring 2024 - Overall Completion Date: June 19, 2026

Minor clean-up work to be completed in 2026

Project Updates:

May 22, 2024:

Wind dependent, the eastbound off-ramp closures on Interstate 90 at exit 406 (Brandon) will be in place on Thursday, May 23, and Friday, May 24, 2024.


May 20, 2024:

April 15, 2024 – May 15,
2024, Completed Work
Express Avenue curb, gutterand asphalt has been completed. Grading continues on north side of I-90 between westbound on-ramp and the railroad bridges. A portion of the I-90 main line is complete and bridge work has begun on the new exit bridge. Approximately half of the storm sewer is complete on S.D. Highway 11. 

Anticipated work in May 15, 2024 – June 15, 2024: Bridge construction will continue as grade preparation on I-90 will continue between the railroad and the west bound on-ramp. Work will continue on underground utilities on both I-90 and Highway 11. Excel to complete power line switch and more paving on I-90 and west bound on-ramp and Highway 11 north of the exit bridge. 


April 25, 2024:

March 26, 2024 - Dakota News Now: 

Watch the full story here


Project Resources (PDFs): 

Interstate 90 Layout

S.D. Highway 11 Layout

DDI Layout

Phasing Year One

Phasing Year Two

Project Photos:

Project Contract Amount:

$41.3 Million

Project Contacts:

Michael Noonan

T&R Contracting, Inc. of Sioux Falls, S.D.
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