U.S. Highway 12 - S.D. Highway 1806 and S.D. Highway 63
Project Summary:
U.S. Highway 12 – From 12 miles east of McLaughlin to west of Mobridge
Full-depth reclamation completed in 2025 and asphalt concrete surfacing on U.S. Highway 12 will address cracking and rough joints. Subgrade reconstruction on S.D. Highway 1806 will correct heaving and restore a normal crown. Additional milling and resurfacing on Highway 1806, S.D. Highway 1806P and S.D. Highway 63 will improve ride quality. Guardrail will be replaced at bridges, and culverts repaired as needed.
Project Updates:
May 21, 2026:
Anticipated Work in June 2026: Work in June will include paving on S.D. Highway 1806 south of U.S. Highway 12, north of U.S. Highway 12, and along the S.D. Highway 1806 spur into Wakpala. Additional work includes guardrail installation on S.D. Highway 63 and S.D. Highway 1806; erosion control at the S.D. Highway 1806 slide area; and application of flush seal, rumble strips, and permanent striping on all routes.
Completed Work in May 2026: Culvert replacement and subgrade repairs on S.D. Highway 1806 north of U.S. Highway 12 have been completed. Slide repair grading on S.D. Highway 1806 south of U.S. Highway 12 has been constructed. Cold milling on all routes has been completed. Asphalt concrete paving has been completed on U.S. Highway 12 west of Mobridge and S.D. Highway 63 north of McLaughlin. Guardrail installation on U.S. Highway 12 has been completed.
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May 4, 2026:
On Monday, May 4, 2026, paving operations are beginning for the multi-year project on U.S. Highway 12 from Mobridge to the west approximately 14 miles. Work will also take place on S.D. Highway 1806 both north and south of Highway 12. The project includes placement of a two-inch lift of asphalt concrete.
Traffic will be reduced to one lane with flaggers and a pilot car guiding traffic during working hours. Motorists should expect delays of up to 15 minutes and are encouraged to reduce speed and use caution when traveling through the work zone. During non-working hours, traffic will return to normal operations.