Irene - S.D. Highway 46 from U.S. Highway 81 to Irene

Project Summary:

This project is a 12-mile-long full reconstruction of S.D. Highway 46 in Yankton County. The project begins at the US81/SD46 intersections and ends at the west edge of the City of Irene. Work on this project will consist of full roadway grading, structure replacement, culvert replacement, interim surfacing, intersection lighting at U.S. Highway 81/S.D. Highway 46 and new permanent signing.

During construction, the highway will be closed to through traffic. Access to residents and landowners adjacent to the project will be maintained, but travelers are encouraged to use the signed detour route around the project. The detour route around the project includes S.D. Highway 19 to U.S. Highway 18 and U.S. Highway 81.

Project Detour Map:

Project Timeline 2023: 

April 4, 2023 - November 2023

Project Updates: 

Sept. 29, 2023:

September Completed Work:  

US81 to 445th Ave: New ROW fencing has been completed with the exception of some barb wire gates. The temporary surfacing has been placed. The topsoil has been shaped on the inslopes and erosion control measured have been installed. The rough grading has been completed at the new box culvert near 445th. 

445th to 449th Ave: Rough grading has been completed and installation of new mainline pipe are being installed. Construction of approaches is ongoing. Finish grading has begun, and placement of salvaged base course has started. 

449th to Irene:  Rough grading is nearlyfinished between 449th and 450th. Approach pipes are being installed and approaches constructed. Placement of salvaged base course will continue from 1.5 miles west of Irene towards town.  

Structures: The new box culvert at 445th has been backfilled and rough grading completed. The floor has been poured out on the large box culvert at 450th Ave.  


Anticipated work in October: 

US81 to 445th Ave: Seeding and clean up will contiue. Temporary pavement marking will be applied to the surface and new permanent signing will be installed. 

445th to 449th Ave: Finish grading and pipe work will continue. Placement of the gravel surfacing and topsoil will follow closely behind the finish grading operations 

449th to Irene: The placement of gravel surfacing will continue near Irene. The remaining grading work will be completed at 450th Ave intersection once the new box culvert has been poured out. Finish grading, topsoil and gravel surfacing will be completed.  

Structures: Concrete work will continue on the large box at 450th Ave. 


News Stories:

Yankton Daily Press & Dakotan 03/30/2023: Highway 46 Project Ready to Roll Again

Project Photos:

2023 Photos: 

Fall 2022:


(First box being constructed, First box complete, Second box location, box backfill)


Spring/Summer 2022: 


Project Contract Amount:

$19.3 million


Project Contacts:

Contractor: Foothills Contracting, Inc.

SDDOT: Brian Wenisch (605) 668-2929 x 48


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