SH-55 Snake River Bridge

Ardurra served as prime consultant for the Idaho Transportation Department's (ITD) 800-foot Snake River bridge replacement project, augmenting ITD staff for the complex 2.5-mile infrastructure improvement. The project required multi-disciplinary engineering expertise spanning roadway design, hydraulic analysis, environmental compliance, and specialized construction management while maintaining traffic operations across this critical river crossing.

The extensive scope encompassed road and drainage design, hydrologic and hydraulic analysis for both bridge and adjacent culvert infrastructure, plus comprehensive traffic control planning for staged construction phases. Strategic coordination with ITD Bridge design teams and complex geotechnical work for MSE and soil nail retaining walls required specialized expertise throughout project development and implementation.

Key Project Services:

• Served as prime consultant for ITD's 800-foot Snake River bridge replacement and 2.5-mile roadway improvement project

• Provided comprehensive road and drainage design with hydrologic and hydraulic analysis for bridge and adjacent culvert infrastructure

• Developed complex traffic control plans for staged construction, maintaining operations across the critical Snake River crossing

• Coordinated with ITD Bridge design teams, ensuring seamless integration of roadway and structural elements

• Conducted specialized geotechnical work for MSE and soil nail retaining walls with comprehensive materials reporting

• Managed environmental and cultural compliance, including threatened and endangered species assessments and public involvement

• Obtained rural county floodplain development permit with comprehensive hydraulic reporting supporting regulatory approval

The project earned an ACEC Engineering Excellence Award in 2021, recognizing exceptional technical achievement and project management excellence. The bridge replacement provides Idaho with enhanced transportation infrastructure while demonstrating innovative approaches to complex river crossing projects and multi-agency coordination supporting regional connectivity and safety improvements.