I-90 Digital Twin Bridge Proof of Technology Evaluation: Final report to FHWA Washington Division

Abstract

The I-90 Digital Twin Proof of Technology Evaluation was a proof-of-concept initiative that evaluated the benefits, limitations, and tradeoffs of implementing Internet of Things (IoT) digital twin (DT) technologies for managing, maintaining, and operating bridge assets. Led by the University of Washington in collaboration with the Washington State Department of Transportation (WSDOT), the collaborative project included Sound Transit, and multiple industry partners.

This project’s objective was to develop and implement a functional digital twin system for critical bridge infrastructure under real-world conditions to demonstrate how IoT sensors, cloud computing platforms, and advanced analytics can improve monitoring of bridge health and operational decision making. The project was installed on the I-90 Homer M. Hadley Memorial Bridge in Seattle, a floating bridge that carries not only vehicles but also light rail.

The project successfully demonstrated that digital twin systems can be developed and deployed in the context of real-world bridge infrastructure, delivering operational value to transportation agencies. The project revealed that successful implementation depends equally on technical integration and organizational alignment. By addressing both dimensions—establishing clear communication channels between informational and operational technology teams, securing early stakeholder buy-in, and demonstrating tangible benefits through actual data—transportation agencies can effectively adopt DT technologies to enhance asset management, safety, and operational efficiency.