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US 20 Simpson Creek Curves Realignment

US 20 Simpson Creek Curves Realignment
Lincoln County, Oregon

US 20 is a major link between Corvallis and Newport, Oregon, built through landslide-prone Coast Range geology in Lincoln County. Tight and narrow curves near Simpson Creek resulted in a high accident rate and impaired freight mobility. ODOT contracted GRI to provide engineering geology, geotechnical engineering, retaining wall design, and construction services to straighten, widen, or repair landslide-affected sections of road. The challenging design included eight new retaining walls, new soil and rock cut slopes up to 160 ft high, and a new bridge over Simpson Creek. Rapid and focused field work, innovative engineering, and effective relationships with ODOT resulted in completion of design and plans and specifications within 4 month of notice to proceed, which allowed ODOT to receive federal ARRA funding. ODOT and GRI provided construction services through completion in 2011, and all elements are performing as designed.  In January 2012, we received an Honor Award for Engineering Excellence from ACEC-Oregon for our work on this project.

Key Staff