MINERAL COUNTY – A section of Interstate 90 in the western part of Mineral County was closed last weekend by the Montana Department of Transportation after debris from a landslide littered the highway making travel too hazardous for westbound motorists.

According to MDT Missoula Maintenance Chief Steve Felix, the landslide occurred sometime early on the morning of Saturday Feb. 7, west of St. Regis. The landslide dumped approximately 250 cubic yards of material near the road and was most likely due to unseasonably warm temperatures in the area causing snow to melt and erode the hillside according to Felix. He said that he was not aware of any accidents, injuries or damage as a result of the slide.

“We did have some rocks come down,” Felix said. “That ended up forcing us to close the westbound lanes of I-90 for several hours while we set up a temporary detour. We did not have to close the entire interstate, just the westbound side. We were able to clean up the area and make it safe for travel but we noticed some increased activity in the afternoon. We had some concerns so we decided to close it down.”

Felix said heavy rain showers Saturday afternoon increased concerns that more material could come down off the hillside and pose a risk to motorists. Traffic was temporarily diverted to Montana Highway 135 and 200. As of Monday Feb. 9, traffic was moving on Interstate 90 using the eastbound lanes and a pilot car for motorists to follow. Felix said the area where the landslide occurred has been known to pose hazardous conditions in the past.

“The area has been prone to rockfall,” Felix said. “We had a pretty good thaw and then with the rain on top of that, it has contributed to the increased activity. We are still seeing activity there and we do still have concerns.”

Felix said crews would be continuing to clean up the debris before the westbound lanes could be reopened. He said the plan was to hire a private contractor to continue to work at the site and to continue to move traffic using the eastbound lanes.