Last week, the SH-3 Goosehaven Road Widening Project was named 2023 Innovative Transportation Solution of the Year by the WTS Spokane/Coeur d’Alene Chapter. In this challenging and creative project, GeoEngineers helped the Idaho Transportation Department (ITD) widen about three miles of State Highway 3 (SH-3) near St. Maries, Idaho.
GeoEngineers staff Dave Lauder, Teresa Dugger, and April Smith joined ITD project manager Erica Aamodt and her team at the WTS Awards Gala on February 15 to receive the award. The SH-3 Goosehaven project will also be recognized with awards from ACEC Idaho on April 15 and WTS Southwest Idaho on April 17.
ITD planned to widen SH-3 by 11 feet to improve safety and transportation capacity along a hazardous three-mile stretch of rural highway next to the St. Joe River. ITD and geotechnical consultant GeoEngineers faced complications based on the road’s location on a narrow earthen levee. Designers needed a lightweight fill material that could support the roadway without needing a wider roadway base, leading them to Expanded Polystyrene Geofoam (EPS Geofoam) blocks.
The final roadway design called for an MSE wall running the full three-mile project length with geofoam blocks as lightweight fill. It was carefully engineered to reduce soft soil loads and perform even in extreme flood events. This design controlled project costs, eliminated the need to acquire right-of-way, and protected nearby wetlands from potential impacts.
Construction began in April 2022, and SH-3 reopened in October despite wet weather and other complications. The widened highway meets ITD’s safety goals with three-foot shoulders, a wider inner lane, and a new guardrail—improving the safety of the traveling public in northwest Idaho for decades to come.
