With landslide cleared, Idaho 14 reopens to traffic as crews rise to challenge

Every few decades, a defining moment comes along that requires the Idaho Transportation Department to react even more swiftly and decisively than usual, in the interest of public safety and restored mobility. It happened in 1976 with the Teton Dam failure, and again 20 years later when floods, blizzards and mudslides hit all over Idaho.

In 1976, the dam failure in eastern Idaho released millions of gallons of water on an unsuspecting public. ITD was instrumental in rebuilding from that disaster, particularly the road and bridges necessary for emergency crews and for restoring a sense of normalcy to the populace. In 1996, ITD was again instrumental in re-establishing connections.

Leap forward another 20 years, and the most recent episode for the agency came in the form of a massive landslide west of north-central Idaho’s Elk City in February. The 2016 Elk City incident unleashed 47 million lbs. of mud, rock and debris on the main highway, cutting off access in and out of a remote Idaho town and threatening grocery and gas deliveries, health-care visits, emergency services, and the livelihood of those who rely on the highway for transport.

Watch the Feb. 18 landslide footage. The video is courtesy of Bret Edwards, an ITD maintenance worker who filmed the original slide as it occurred.

The slide loosened more than 100,000 cubic yards of dirt, rock and debris, 20 feet deep in places, dumping material across a 500-foot-wide stretch of Idaho 14 and closing the road.

Click here for aerial of landslide.

Watch video showing initial days of cleanup.

Two months later, a second slide in roughly the same area brought down more material and pushed what was already loose debris even closer to the highway.

The final shovels of dirt were removed in the last half of August.

With the landslide cleared, the road opened to traffic without restriction Aug. 24.

Crews paved the new route last week, will re-stripe it for traffic next week if weather holds, and will install guardrail in the coming weeks.

Click here for repaved road.

“It was a huge challenge,” said ITD District Engineer Dave Kuisti. “The last time District 2 faced a challenge like this was in 1996, when flooding wiped out several area roadways.”

“Because the original slide was covered in snow, and occurred right at dusk, we didn’t know the full extent of it until we were able to get up on top in the light of day and do some exploration,” District Engineering Manager Doral Hoff explained.

The biggest safety challenge rested in the heart of the slide. Estimated at more than 1,200 cubic yards, crews had to blast and reduce a massive boulder, estimated at 30 feet tall and 80 feet wide, before moving forward. The boulder was reduced March 19-20.

Watch boulder reduction video.

Eventually, an area extending about 900 feet up the hillside was cleared.

Nearly 15,500 truckloads have been hauled from the area, accounting for more than 235,000 cubic yards of debris.

A few weeks ago, crews removed the elevated catchment road created in the aftermath of the slide so that clean up efforts could commence from both sides of the slide area, and to accommodate local emergency traffic.

The cleanup took about six months, and cost close to $3.5 million (federal emergency-relief funds).

A curve in the highway was also straightened to ensure future safety.

Watch video footage with aerials at the end

To encourage new vegetation to take root on the hillside, crews plan to hydro-seed the upper portion of the slide area. Crews also plan to do some rock scaling and rock bolting, a process in which a long anchor bolt is drilled into the rock formation, transferring the load from the exterior to the more stable interior of the rock mass.

All along the way, the department sought to expedite repairs, but the speed of excavation was always viewed through the lens of safety.

“There was definitely pressure to get the road back open as quickly as possible, but safety – for our workers and for area motorists and citizens – had to be our overriding concern,” Hoff added.
“As soon as we saw the economic and physical impact to the residents, ITD switched the focus of the work to provide a safe, reliable access first,” explained Ryan West of West Company, the contractor on the cleanup. “We re-worked the job with ITD to focus on that, and then look at the work process of getting it all cleaned up as a secondary activity once that safety was ensured.”

“This was unique in terms of complexity and challenge,” said West. “We understand the nature of emergency contracts – the project owner is under a lot of pressure to capture the full scope of the work to be done and to get started. It had to be done thoroughly and we were prepared.”

Communication was also critical.

“We worked hard to keep regular communication channels open with residents, with the county, and with all stakeholders,” said Kuisti. This was especially important early in the process, Kuisti added.

Communication with community members, city officials, forest service personnel, homeowners and other interested stakeholders during the initial stages of the slide clean up were critical in setting expectations for the effort.

ITD held twice-weekly conference calls with city and county leaders, representatives from involved agencies, and law enforcement officials in March and April as cleanup began. Several town hall meetings were also held to inform the community and supply status updates, and more than a dozen news releases were sent with the media, posted on the ITD Facebook and Twitter accounts, and shared with the county sheriff’s office for posting in Elk City.

“This project really involved a lot of teamwork, collaboration and support,” Kuisti said. “Idaho County took quick action and within days of the closure, they had cleared a Forest Service road of an incredible amount of snow and opened it to allow essential access and supplies into Elk City. In fact, the Forest Service was a huge partner from the very beginning.”

There were a number of other organizations involved, from the county to Elk City, and from the Federal Highway Administration and the Bureau of Homeland Security, to the Department of Environmental Quality and the (Nez Perce) Tribe,” said Kuisti. “We really appreciate the other ITD districts around the state that loaned us people and equipment. It really was the result of a team coming together.”

“Safety and mobility remained paramount throughout the project, and economic opportunity was restored to the county and to Elk City,” Hoff said.


Published 09-23-16