SH-21 reopens between Grandjean and Banner Summit

SH 21 reopens near Lowman Dec 2025

State Highway 21 between milepost 93 near Grandjean and milepost 106 at Banner Summit is now open to traffic.

The Idaho Transportation Department closed the highway earlier this month due to a rockfall that blocked the roadway. Crews have since cleared the debris and completed rock scaling operations to remove unstable material from the slope above the highway and ensure the area is safe.

Motorists can now travel through the area without restrictions. Drivers should continue to use caution in mountainous areas, remain alert for changing conditions, and watch for falling rocks, especially during periods of wet weather or temperature changes.

ITD thanks the public for their patience while crews worked to safely reopen the highway.

For the latest road conditions, visit 511.idaho.gov or call 511 before you travel.