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U.S. Highway 16A - From two miles east of Custer to Jct. S.D. Highway 36
U.S. Highway 16A - From two miles east of Custer to Jct. S.D. Highway 36
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U.S. Highway 16A - From two miles east of Custer to Jct. S.D. Highway 36
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Project Summary:
The project consists of the replacement of various pipe culverts on U.S. Highway 16A that have exceeded their useful life. Additional work on the project includes removing and replacing existing asphalt surfacing, repairing in-slope erosion adjacent to the highway, and improving the intersection of U.S. Highway 16A and Wildlife Loop Road.
The project also consists of the replacement of a concrete arch culvert that has exceeded its useful life.
Project Timeline:
Fall 2025 - Fall 2026
- Work will not begin before Aug. 12, 2025
- The detour will be in effect from Sept. 29, 2025, to April 3, 2026
- No work from June 22, 2026, to Aug. 17, 2026
- The overall completion date is Oct. 30, 2026
Project Detour Map:
Project Photos:
Construction Projects
Planning
Carbon Reduction Strategy
Freight Plan
Long Range Plan
Metropolitan Planning Organization
Non-state Public Road Inventory
Pavement Condition Monitoring
Pavement Management
South Dakota EV Fast Charging Plan
Statewide Transportation Improvement Program – STIP
Transportation Asset Management Plan (TAMP)
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Special Studies
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SPR
US Highway 16 Corridor Study
I-229 Exit 3 (Minnesota Avenue) and Exit 4 (Cliff Avenue) Interchange & Environmental Study
I-229 Exit 6 (10th Street) Interchange Study
SD44 - Platte/Winner Bridge Corridor Study
I-90 Exit 46 (Elk Creek Road) Interchange Modification Study
I-90 Exit 63 (Box Elder/Ellsworth AFB Commercial Gate) Interchange Study
U.S. 385 Roadway Improvement Study
SD 100 Corridor Preservation Project
US14A/US85/Deadwood Box Corridor Study
South Veterans Parkway (Highway 100)
US Highway 212/Forest City Bridge Corridor Study
Union County Master Transportation Plan Study
Tabor to Platte Rail to Trail Feasibility Study
© 2025 State of South Dakota. All Rights Reserved.
South Dakota Department of Transportation
Becker-Hansen Building
700 E. Broadway Ave.
Pierre, SD 57501
Becker-Hansen Building
700 E. Broadway Ave.
Pierre, SD 57501
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© 2025 State of South Dakota. All Rights Reserved.
South Dakota Department of Transportation
Becker-Hansen Building
700 E. Broadway Ave.
Pierre, SD 57501
Becker-Hansen Building
700 E. Broadway Ave.
Pierre, SD 57501
Powered by:
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