The 2026 American Association of State Highway Transportation Officials (AASHTO) National Award is the latest recognition given to the State Route (SR) 520 Montlake Lid and Bridges project. This project has transformed regional mobility between Seattle and Bellevue while setting new standards for engineering, environmental stewardship, and multi-agency collaboration.
The SR 520 Montlake Lid and Bridge Replacement project integrates green space with bike, pedestrian, and regional transit infrastructure. It uses sustainable stormwater strategies and connects to the seismically upgraded floating bridge. Photo © WSDOT, via Flickr Creative Commons.
Over nearly two decades, Confluence helped guide one of Washington’s largest and most complex transportation investments through the environmental review and approval process. These efforts helped WSDOT maintain an ambitious schedule while meeting rigorous environmental requirements and advancing long-term ecological benefits throughout the project corridor.
“We are proud to be on WSDOT’s SR 520 team. As permitting lead, we delivered nearly 75 federal, state, and local permits and led mitigation and restoration efforts on 185 acres of habitat across 14 restoration sites. It’s very satisfying to be part of a team of talented professionals that protected critical natural resources while delivering the project on time,” said Scott White, Confluence Senior Principal.
The recent AASHTO recognition adds to a list of awards earned by various components of the SR 520 program:
SR 520 Montlake Lid and Bridges Project Awards (2025–2026)
- Transportation Project of the Year 2025 (The American Public Works Association for projects over $75 million)
- Top 10 Bridges – No. 3, 2025 (Roads & Bridges Magazine)
- National Honor Award, 2026 (American Council of Engineering Companies (ACEC) Engineering Excellence Awards)
- PCI Design Award, 2026 (Precast/Prestressed Concrete Institute category for mid-span bridges)
SR 520 Floating Bridge and Landings Project Awards (2025–2026)
- Grand Conceptor Award, 2017 (ACEC’s top national engineering feat honor for the main floating span design)
- DBIA Awards, 2015–2016 (Design-Build Institute of America National Award of Merit and Excellence in Design)
- ASCE Seattle Section, 2017 (Local Outstanding Civil Engineering Award for Structures)
Collectively, these awards reflect the extraordinary collaboration among WSDOT, engineers, contractors, environmental specialists, regulators, and community partners who brought this landmark program to life and Confluence was proud to be part of the team!
*