Wyoming Department of Transportation Continues work Reconstructing Big Fill Landslide

Winter weather may have started showing itself in Wyoming, but crews are still working on reconstructing WY 22 at the site of this summer’s Big Fill slide. Doug McGee provides an update on the Big Fill Slide reconstruction effort in this week‘s WYDOT Report.

“Crews in Northwest Wyoming took advantage of a mild fall to push forward on reconstruction of the Big Fill slide on Teton Pass" notes Doug McGee with Public Affairs.

The project involves rebuilding the embankment from the ground up. This summer, crews removed old fill material and installed a soil nail wall to protect the work zone.

Resident Engineer Bob Hammond stated, "And we started work package two back in late September. That consists of putting in some micro piles that go into the ground that will stabilize the area. And then it includes putting in a bunch of drain rock, which we’ve put in the bottom foundation layers. And that will go up all the sides to help drain all the sides as well."

With micropiles and drainage in place, crews are now re-filling the big fill using a special lightweight material.

Hammond says, "We’re bringing in a manufactured product. It's a foamed glass aggregate. It's produced out of recycled glass. Native soil is typically 115 to 120 pounds per cubic foot. This material here weighs about 20 pounds per cubic foot."

The material is actually too light for the design, so the fill is built in two-foot layers, alternating between lightweight fill and native dirt every four feet.

"And on top of each one of those layers, every two feet, is a layer of geogrid. That just helps reinforce anything. So a slide plane won't slice through that lightweight aggregate at all."

Rebuilding this way gives the fill stability, but it is time-consuming. Crews have been working to get as much done as possible before winter weather shuts down the project for the season.

Work will resume in the spring with the goal of completing the project by July.