BOISE, Idaho — Idaho Transportation Department crews are working to clean up debris and inspecting infrastructure after Tuesday's 6.5 magnitude earthquake.
The quake struck late Tuesday afternoon in the Central Idaho mountains west of Challis and was felt throughout Idaho and six surrounding states.
According to ITD spokesman Jake Melder, several Idaho highways saw rockfall following the quake, including Highway 75 near Stanley, Highway 21 north and south of Lowman, Highway 55 between Horseshoe Bend and Cascade, and Highway 52 east of Emmett.
Maintenance crews were immediately deployed to clear the hazards from the roadway and ensure the road was safe for travel, Melder said.
Additional falling rocks caused by aftershocks have also been reported, and crews are patrolling high-risk areas to actively clean rocks from the highway.
The transportation department is urging drivers to use extra caution when driving in those areas.
Melder said crews have surveyed bridges for damage, and so far, they have not found anything of concern. Meanwhile, ITD is conducting a more detailed analysis of the condition of Idaho's bridges, especially those closer to the earthquake's epicenter.
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HIGHWAY 21 CLOSED
A section of Idaho Highway 21 between Lowman and Stanley remains closed Wednesday after a combination of weather and the quake sent snow and debris sliding onto the roadway.
According to ITD, a storm system dumped 27 inches of snow in the Canyon Creek section of Highway 21, from Grandjean to Banner Summit. This increased the risk of avalanches and ITD closed the highway at 2 p.m. Tuesday, several hours before the earthquake.
The quake caused several slides to fall onto the highway in the closed section.
"Crews entered the area to begin clean-up Tuesday night and quickly found the landslides were extensive," Melder said in a news release.
Due to the threat of aftershocks in the area, the crew withdrew from the canyon and will stay out until the US Geological Survey determines it's safe to be there. Melder said it could be "many days" before the closed stretch reopens.
Idaho Highway 75 and U.S. 93 remain open to access Stanley.
