Phase 1 of the Oregon Department of Transportation Highway 20 Sheep Creek Bridge project will begin soon, impacting traffic from July through October.
During the project, traffic impacts include intermittent single-lane restrictions, flaggers controlling travel and delays of up to 45 minutes.
A second phase will complete the project in summer 2016.
This project will address earth movement, and bridge and highway damage from an active landslide on the east end of the Sheep Creek Bridge, located approximately 25 miles east of Sweet Home, milepost 56.6.
Sheep Creek Bridge was built with its eastern abutment located on an active slide. When the bridge was replaced in 1962, the new bridge was designed to accommodate slide movement and be adjusted as the earth around it moved.
In 1993, 2006 and 2011, the east abutment was adjusted for the movement. Until about 2010, the earth movement was measured at approximately one inch per year. For the past four years, however, the movement has increased to 6 to 7 inches per year.
This project won’t change the need for the bridge to continue to accommodate earth movement. But this project is designed to redirect and reduce the slide activity so that the impact to the bridge will be consistent and predictable, and therefore, more manageable.
The Sheep Creek Bridge project was identified during development of the South Santiam Forest Corridor, an Oregon Solutions collaborative effort involving partners from agencies of federal, state, county, tribal, and local governments, as well as representatives from private industry and non-profits.