I-29 and 85th Street Interchange in Sioux Falls

Project Summary:

The project includes construction of a Diverging Diamond Interchange (DDI), structure development work, grading, concrete surfacing, curb and gutter, storm sewer, lighting, signals, permanent signing, and pavement marking.

Travel Impacts: Interstate traffic will be reduced to a single lane while operations are being conducted adjacent to the Interstate 29 lanes. Traffic control measures will be in place to help guide motorists through the work zone. 

Business Access: Access will be maintained at 85th Street and Sundowner Avenue and Tall Grass Avenue.

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Text 85thStreetDDI to 605-566-4041

Project Timeline:

Nov. 2025 - Nov. 2027
The contractor will establish a timeline in the spring of 2026. 

Project Updates:

Coming Soon

View 85th Street updates on the City of Sioux Falls website: I-29 & 85th Street Interchange - City of Sioux Falls