Idaho Transportation Department – Riggins Rockslide Response

In July 2020, part of the rocky slope above US-95 at milepost 188 fell and blocked the primary north-south route in Idaho for five days. A second event followed this initial failure a week later. While no crashes occurred, those rockslide events deposited more than 20,000 cubic yards of rock and debris on the highway, shutting down key state travel corridors and causing goods, services, and people to take an hours-long detour. Not only was immediate response needed to restore connectivity, a long-term repair proved paramount in addressing continued movement on the slope that would be required to prevent future disruptions. The Idaho Transportation Department completed a $3.2 million emergency stabilization project that relied on community partnerships. Even through unforeseen challenges – such as the discovery of naturally occurring asbestos on the slope – the agency help drivers get safely back on the road quickly and efficiently.