POLLOCK -- Both U.S. Highway 95 and Old Pollock Road are expected to close this Friday evening, Aug. 28, to allow crews to blast an estimated 14,000 cubic yards of unstable rock from the slope, the same amount that has fallen to the road since the first slide at milepost 188 on July 3.
According to the Idaho Transportation Department, traffic will be shifted onto Old Pollock Road Thursday night, Aug 27, in anticipation of the blast. The complete closure on Friday is expected to last just one hour, and after the blast, traffic will be allowed to travel through the area on Old Pollock Road.
“Our priority is to ensure that the residual rock is stable after the blast and to clear the temporary road around the base of the slide,” operations engineer Jared Hopkins said. “That could take up to a week, during which we will need to keep traffic on Old Pollock Road.”
This blast is the first of two planned to remove material from the slope. An update will be sent later this week with the timing of the blast on Friday evening. The second blast has not yet been scheduled.
After blasting, crews will clear the detour around the base of the slide. Geotechnical experts will finish dislodging any loose material before using steel bolts to secure the remaining rock in place. Wire fencing will be positioned to cover the surfaces between bolts, and drains will also be installed.
“Reinforcing the slope with bolts and fencing will be the most time-consuming task but will not impact traffic,” Hopkins said.
Once work on the rock face is complete, contractors will dismantle the berm, repair U.S. 95 and remove the detour around the base of the slide.
“Over the next two months, drivers should expect intermittent closures on U.S.95 or Old Pollock Road,” Hopkins said. “We will alternate between the two routes to accommodate traffic, with a complete closure of both only planned for the day we blast.”
Repairs are expected to cost $3 million and will be completed by Scarsella Brothers, Inc. out of Seattle.