Spearfish, SD – Beginning Monday, Nov. 9, motorists traveling on Interstate 90 near Exit 10 will encounter new traffic patterns as the South Dakota Department of Transportation (SDDOT) moves into the final phase of a $1.3 million intersection improvement project.
New “loon” turnaround opens
The centerpiece of the upgrade is a newly paved turnaround, locally called a “loon,” which will open the same day construction starts. Designed to give drivers a dedicated, safer place to make U‑turns, the turnaround replaces the previous, less‑controlled maneuver that often caused congestion and near‑misses.
Additional lane work and temporary restrictions
Alongside the turnaround, crews will begin installing a new median and a dedicated turn lane on North Avenue. During this work, drivers will not be able to turn left from Old Highway 14, and northbound traffic on North Avenue will be barred from turning left onto Old Highway 14. The SDDOT advises motorists heading to Old Highway 14 to use Exit 8 as an alternate route.
All entrance and exit ramps at Exit 10 will remain open, and new traffic signals are slated for the eastbound I‑90 off‑ramp and North Avenue, with installation expected in January 2027.
Project timeline and contractor
The construction contract was awarded to Tru‑Form Construction of Black Hawk. The agency expects the work to be completed by Nov. 20, giving drivers roughly two weeks of adjusted traffic flow before the improvements are fully operational.
Motorists are urged to slow down, obey posted signs, and stay alert for changing patterns throughout the construction zone. The SDDOT emphasizes that these temporary measures are intended to protect both drivers and workers while the project moves toward completion.
Why the upgrades matter
Spearfish’s growing population and its role as a gateway to the Black Hills tourism corridor have increased traffic volumes on I‑90. By adding a dedicated turnaround and improving lane configurations, the state aims to reduce bottlenecks, lower the risk of accidents, and support smoother travel for residents, commuters, and visitors alike.
Local business owners have welcomed the project, noting that smoother traffic flow can benefit downtown commerce, especially during the busy winter tourism season.
What drivers should do now
Until the construction wraps up, drivers should follow these simple steps:
- Use Exit 8 if you need to reach Old Highway 14.
- Observe all posted signage and reduced speed limits.
- Allow extra travel time for the brief detours and lane closures.
For the latest updates, motorists can visit the SDDOT website or follow local news outlets covering the Spearfish area.
Original reporting: KOTA (Gray) – local — read the source article.
