Both westbound lanes of I-90 could be closed for a week after a landslide spilled onto the highway on Sunday.
The slide happened 6.5 miles east of the summit of Lookout Pass, near Saltese. Westbound traffic was forced to detour to Montana 200 through 1 p.m. Monday afternoon.
A geologic assessment team confirmed early Monday afternoon that the slope is wet and highly unstable. MDT crews trying to clear rock and debris at the base of the slide were forced to retreat as another chunk of hillside gave way and sent rocks careening down the slope.
While MDT continues to clear the rock, follow-up assessments of the slope must be done to determine just what crews will be dealing with in the coming days. The hope is that the slope will be able to dry out in the days ahead. Any rain, no matter how small, will help grease the wheels and increase the risk of additional rock falls.
For the time being westbound traffic on I-90 is diverted to an eastbound lane in the slide area. Traffic in both directions is being escorted by MDT vehicles for safety until further assessments of the area are completed.
No wide loads are allowed over the pass in order to accommodate closely spaced traffic. Expect delays.