Highway 95 near Riggins to remain closed after boulders came down overnight

Posted at 11:45 AM, Jul 03, 2020
and last updated 2020-07-10 18:36:19-04

RIGGINS — UPDATE (July 10): Highway 95 south of Riggins will remain closed after massive boulders came down overnight. The slope above the highway remains too unstable for traffic or rock removal crews to be in the area.


“The highway will remain closed until we are able to evaluate this new development and determine the best option to safely stabilize the slope.” Operations Engineer Jared Hopkins said.

There is a temporary gravel road to detour traffic around the base of the slide, but movement on the slope closed it on July 8. Old Pollock Road will be open as a detour around the slide during daytime hours (around 7 a.m. to 9 p.m.) but will be closed overnight for crews to perform maintenance operations on the road.

Officials with the Payette National Forest do not recommend using French Creek Road as a detour route around the slide. The road is a high clearance road (not for two-wheel drive vehicles) and is not recommended for travel by inexperienced mountain road drivers. Many vehicles have been driven off the road, but have been able to be recovered before a serious accident happened.

French Creek Road is a single lane, dirt road that has not been graded and has limited pull-outs. Two-way traffic is happening on this road and the limited number of pull-outs makes it challenging for drivers to pass each other.

“It’s very important that we maintain the integrity of Old Pollock Road so that it can continue to serve as a viable option for detouring traffic during this time,” Hopkins said.

Early next week, crews will again be scaling the slope and surveying the area.

“Currently there are a lot of overhanging boulders and ledges,” stated Hopkins. “We don’t yet know how stable these are and until we are able to further evaluate the area, crews will not be able to engage in rock removal operations.”

The slope and area around the slide is considered extremely hazardous and ITD is asking people to stay away from the area for their safety. The department is also asking drivers choosing to use the Old Pollock Road detour to ensure they drive attentively in order to keep traffic flowing.

“The proven unpredictability of this slide requires that we remain flexible,” Hopkins said. “While our goal is to safely reopen the highway as soon as possible, we are very thankful that no one has been injured and will focus our efforts to ensure that it remains that way.”

UPDATE (July 8): Drivers traveling through Riggins could once again face significant delays.

ITD says the recently reopened detour around the rock slide-caused closure south of Riggins will be closed again, likely for at least two days.

Crews discovered a significant amount of movement on the slope.

“Between Monday and today, one of our survey targets moved nearly two inches,” Operations Engineer Jared Hopkins said. “That kind of activity may not sound like much, but in terms of geological movement it is alarming.”

During the closure, Old Pollock Road will serve as a detour for both passenger and commercial traffic, but it is really a last resort.

ITD estimates the slow-going, four-mile, one-lane gravel road could take up the three hours to get through. Repairs to that road were completed Wednesday night. Flaggers will direct the alternating traffic flow.

UPDATE (July 8): One lane of Highway 95 between Pollock and Riggins will reopen at 11 a.m. and stay open until 9 p.m. The highway has been closed since July 3, after a rockslide closed it at milepost 188.

Drivers will pass around the slide on a temporary gravel road. There will be lengthy delays as only a limited number of vehicles will be allowed to pass underneath the slope at one time. Scaling activity above will also require periodic 20-minute closures over the next couple of days.

"We have built a rock berm and placed large container boxes to shield traffic from any unforeseen rockfall," Operations Engineer Jared Hopkins said. "A spotter and a surveyor will watch the hillside and be ready to have flaggers close the highway in the unlikely event it becomes unstable."

Starting Thursday, ITD plans to open the highway from 7 a.m. to 9 p.m. each day. 30 minutes before the highway is closed each night, the staff at barricades in Riggins and New Meadows will turn traffic away. Crews will continue breaking down rocks and pushing them up against the existing berm to make it taller and provide more room for any more debris.


Improvements to Old Pollock Road will be finished today, serving as another one-lane gravel option for local commuters only.

"For the time being, motorists should plan for congestion and expect the highway to be closed at night when we can't monitor the slope," Hopkins said. “We expect to keep flagging and monitoring for several weeks until we identify a long-term solution.”

Another update will be released when a long-term solution is identified next week.

UPDATE (July 7): After a massive rockslide last week, Highway 95 is expected to reopen to drivers on July 8. Recent rain, however, could affect the stability of the slope.

Rock scalers were on scene Tuesday to dislodge any loose materials. The section of Highway 95 between Pollock and Riggins will only be open during the day to allow for more observation.

UPDATE (12 p.m., July 6): Results from geotechnical surveys done on the rock slide shows significantly less movement on the slope, but Highway 95 will remain closed to allow more monitoring. Outside experts are examining the slope today to identify short-term and long-term options to stabilize the area. They are also dislodging any loose material.

“By tomorrow morning, we will have more data to compare to the baseline conditions of the slope,” Operations Engineer Jared Hopkins said.

Crews have finished building a temporary road around the slide at milepost 188 and have placed barriers to protect future traffic from any rockfall.


“When survey results and on-slope evaluations prove that the slide is stable, we will look to open the highway for short periods of time,” Hopkins said. “In the meantime, we are evaluating the condition of Old Pollock Road to see how we may be able to help the county with a locals-only detour.”

ITD has submitted feedback to Google Maps to show Old Pollock Road is currently not open to traffic. There is no detour around the slide, which has kept the highway closed since Friday morning.

UPDATE (2:40 p.m., July 5): Initially, Idaho Transportation Department (ITD) officials said they suspected U.S. Highway 95 would be safe to reopen Sunday afternoon. Now, they have announced that they are no longer opening the highway to traffic between Pollock and Riggins, to allow for continued monitoring of the slide at milepost 188.

"We know this is contradictory to what we had hoped to accomplish today and will cause long detours for travelers heading home," ITD District Engineer Doral Hoff said. "However, without enough data and uncertainty about an apparent gap at the top of the hillside, we are concerned it might be active still."

Yesterday around 4:30 p.m., crews left the site once a crack in the rock face became visible from below. They had been working on a temporary road around the slide as well as building a rock berm and placing container boxes to shield traffic once allowed to pass through.

ORIGINAL STORY (July 3): Highway 95 is temporarily closed after a large rockslide blocked the road. The closure starts at milepost 161 to milepost 188, New Meadows to five miles south of the Riggins area.

Idaho State Police says an one alternate route from southwest Idaho to Central or North Idaho would be I-84 west connecting to Highway 12 or I-90 east at Tri-Cities. The Idaho County Sheriff's Office does not have an estimated time as to when it will be cleaned up.

The Forest Service advises French Creek Road is not a recommended, nor an official detour for Highway 95.

The sheriff's office will provide an update on their social media accounts when the road is clear. You can also check for updates.