The $112-million Sand Creek Byway was the largest single contract in Idaho Transportation Dept. history. The 2.1-mile project realigned a segment of U.S. 95 that bypasses Sandpoint in northern Idaho.

Photo courtesy of Parsons RCI Inc.
The 2.1-mile project realigned a segment of U.S. 95 that bypasses Sandpoint in northern Idaho.

The project was constructed adjacent to an existing historic railway depot, several operating commercial buildings and the Burlington Northern Santa Fe railroad. Sensitive environments nearby include Sand Creek, Lake Pend Oreille, bald eagle nesting areas and the economically vital City Beach recreational area.

Major project features included construction of four steel-girder highway bridges, more than 30 mechanically stabilized earth and cast-in-place walls and two pedestrian underpasses. There also are a pedestrian bridge and a bike path that parallel the new highway.

Geotechnical conditions required that all in-situ soils be excavated and removed from the site, with fill imported to match the new roadway's line and grade. Parsons used large ground heaters that prevented soils from freezing through the winter construction.

Ground stabilization included wick drains, cellular concrete and deep soil mixing. Structural excavation and shoreline extension work required inflatable dams and several cofferdams. Despite these challenges, the job was finished in just 78% of the contract time.

 

Best Intermountain Highway/Bridges Project

Judges' Special Recognition

U.S. 95 Sand Creek Byway

Sandpoint, Idaho