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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Project Timeline:

Spring 2024 - Overall Completion Date: June 2026

Minor clean-up work to be completed in 2026

Project Updates:

May 20, 2025:

April 15, 2025 – May 15, 2025, Completed Work: The eastbound lanes have been crushed and incorporated into the new grade. The north end of S.D. Highway 11 has also been crushed and is being incorporated into the new grade of Highway 11. A portion of storm sewer has been placed in the area of the westbound off-ramp which is now closed. The large panel wall on the north side of the westbound lanes of Interstate 90 is complete and the north abutment of the exit bridge is complete. The eastbound bridge of the Burlington Northern and Santa Fe (BNSF) rail line has been removed.

Anticipated work May 15, 2025 – June 15, 2025: A closure of the eastbound on-ramp will take place. Work for next month will focus on grading, storm sewer, and storm sewer structures. Graveling of the westbound off-ramp is anticipated and a portion of the concrete pavement construction will begin. Grading on the eastbound on-ramp will continue and storm sewer is expected to be placed. Construction of the large panel wall will continue, and the south abutment of the exit bridge will be near complete. Work on the eastbound railroad bridge will commence.

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May 12, 2025 - Press Release:

On Monday, May 12, 2025, the eastbound on-ramp to Interstate 90 at Brandon (exit 406) will be closing as part of the Diverging Diamond Interchange (DDI) construction project. Motorists in the Brandon area planning to travel eastbound on I-90 should use exit 410 via the signed route using S.D. Highway 11, County Road 138 (Aspen Boulevard), and County Road 105. This closure and detour will be in place until the reconstruction of the eastbound on-ramp at exit 406 is complete in mid-July 2025.

The second phase of reconstruction on this DDI project includes completing the remaining on- and off-ramps, the eastbound lanes of I-90, the Exit Bridge, and the replacement of the eastbound I-90 bridge over the BNSF railroad.

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April 25, 2024:

March 26, 2024 - Dakota News Now:

Watch the full story here