UPDATE (3/23): Good news for travelers on Highway 55. Starting Wednesday, the Idaho Transportation Department will resume daily openings on the roadway that was closed due to a rockslide.
ITD says engineers examined the rocky hillside and found it stable enough to resume work and traffic flow. Starting Wednesday, they will open one lane of alternating traffic from 8 a.m to 3 p.m. Outside of those hours, the road will be closed. Drivers should expect at least 15-minute delays.
Crews say they will shut down the road immediately if weather or hillside conditions change. They plan on shutting down the road completely in about a week to blast away the remaining rock outcropping.
UPDATE (3/18): The Idaho Transportation Department says after an evaluation by a national rock slide expert, Idaho Highway 55 will remain closed at least through March 21 for safety reasons. ITD says they are working to safely open the road to traffic and will monitor conditions through the weekend during the forecasted storms.
ITD will review conditions ahead of the next week with the experts and plans to provide another update during the afternoon on March 21, so travelers can make appropriate plans.
“Safety of the traveling public, as well as the crews who are on-site, is our top priority,” said Jason Brinkman, ITD District 3 Engineering Manager. “These decisions are not taken lightly. We understand that this road closure is not ideal, and are working extensively to reopen the road as soon as safely feasible.”
ITD advises drivers to use U.S. 95 as an alternate route.
ORIGINAL STORY: The Idaho Transportation Department says a rockslide closed Highway 55 near Smiths Ferry late on March 15. The slide is located in the work zone for the Smiths Ferry to Rainbow Bridge highway improvement project.
ITD says at this time there is no indication the work directly triggered the slide. There are no known injuries at this time, but an excavator being used for the project did get hit.
Geotechnical experts are evaluating the situation, but early observations show the situation remains dangerous and the highway will remain closed will crews address the slide. The current plan is to follow closure protocols established for the highway project during a blasting event, which requires a complete closure from 10 a.m. to 2 p.m., according to ITD.
The slide removed rock and earth from beneath a spire on the hillside. ITD says the stability of that spire is uncertain and the area is considered dangerous. Those planning to travel between Valley County and Boise County should consider alternate routes.
“The rock and earth in this area is historically unstable,” said project manager Alex Deduck. “We saw a significant slide in 2019 just south of here. Last night’s slide is another example why our project is so important.”
The Smiths Ferry to Rainbow Bridge project will remove thousands of tons of rock and earth from the adjacent hillside to widen the highway, create rock catchment ditches and reduce the severity of curves. Click here to read more about the project.
The Idaho Transporation Department says they will give another update on the rockslide Tuesday afternoon.
