City of The Dalles, OR

East Scenic Drive Stabilization Project

E. Scenic Dr. soldier pile wallThe East Scenic Drive Stabilization Project is located within the historic Kelly Avenue Landslide area. Phase 3 of the project will begin in August 2022 and is due for completion by the end of the month. The purpose of the project is to continue improvements along East Scenic Drive. The roadway has deteriorated and the embankment is failing between Jefferson Street and Esther Way.

The Kelly Avenue Landslide originated at a depth of about 200 feet. It was first investigated and re-mediated in the late 1980's. The City installed de-watering wells to mitigate landslide movements. Ongoing monitoring shows that the wells have performed as expected. The landslide has been deemed stable.

But landslide area monitoring has indicated earth shifting at a shallow depth of approximately 10 feet. In 2011 engineers determined the cause to be shifting embankment fill material. The shifting of East Scenic Drive is not related to the original Kelly Avenue Landslide. They also determined that a soldier pile retaining wall system would be the best solution to stabilize the embankment.

The City has tackled this large public works project in three phases. A total of 1,100 feet of soldier pile retaining wall system is planned. In 2015, Phase 1 installed nearly 600 linear feet of retaining wall. Phase 1 also included reconstruction of the storm water collection system.

Before Phase 2 began a new sanitary sewer main was installed. Phase 2 constructed about 240 linear feet of retaining wall in 2019. Phase 3 will install 265 feet, which is the final segment of the soldier pile retaining wall system. Phase 4 will completely rebuild the East Scenic Drive roadway system between Jefferson Street and Esther Way.