Interstate 90 Kennebec to Reliance

Project Summary:

Shoulders will be milled and resurfaced to improve safety and durability. An asphalt surface treatment will also be applied to help protect the roadway from moisture and extend the life of the pavement.

Project Updates:

April 23, 2026: 

A 15 mile shoulder project is scheduled to begin Tuesday, April 28, 2026, on eastbound Interstate 90 between Kennebec and Reliance. Shoulders will be milled and resurfaced to improve safety and durability. An asphalt surface treatment will also be applied to help protect the roadway from moisture and extend the life of the pavement. Through a collaborative value engineering effort between the South Dakota Department of Transportation (SDDOT) and the project contractor, the original construction schedule has been significantly shortened to meet the needs of travelers.

Under the revised plan, all traffic for the duration of 15 miles will be shifted into the westbound lanes in a two way traffic configuration. This expanded two-way traffic configuration allows construction crews to work more efficiently and reduces the overall project duration. With this revised configuration, the construction period is shortened by approximately 14 weeks. The original planned project completion date was November 2026. The project is now anticipated to be complete by Friday, July 31, 2026, weather dependent.

Traveler Impacts:

The traffic shift and construction staging required for this two-way traffic configuration will require several closures and detours for eastbound I-90 travelers.

Ramp Closures and Detours:

• Exit 241 at Lyman (eastbound) will be closed;

• Exit 248 to Reliance (eastbound) will be closed;

  • Access to the City of Reliance will be detoured to exit 251, using S.D. Highway 47;

• Over width westbound traffic headed toward Rapid City will enter the two way traffic section and exit at exit 251; and

• Over width eastbound Oacoma/Chamberlain traffic will exit at exit 235 (Kennebec) and follow the posted detour to exit 251.

Due to the layout of existing interchanges, the eastern portion of the project will still require some lane closures in certain areas rather than a full traffic shift.

SDDOT reminds motorists to use caution, remain alert, and follow all posted speed limits when traveling through the work zone.

Motorists may observe intervals where portions of the corridor appear inactive. These periods are normal and part of the sequencing for the shoulder paving and concrete repair operations. Thanks to the revised construction plan, the traveling public will experience less overall disruption during the 2026 construction season for this I-90 shoulder project.

Project Photos: