All posts by trac

Bridging the Gap: Identifying and Addressing Active Transportation Disparities in Underserved Rural Residential Clusters

Residents of rural residential clusters (RRCs) in Washington often face systemic barriers to safe, affordable, and reliable transportation, resulting in disproportionate hardship and limited access to essential services. The goal of this study is to advance transportation equity by identifying, analyzing, and addressing active transportation (AT) disparities in transportation-disadvantaged RRCs. For this research, an RRC is defined as a small, unincorporated cluster of adjacent homes located along a state highway or major county road. The study area encompasses nine counties in western Washington state, extending from Lewis County northward to the Canadian border. For this project, the researchers are developing a geospatial method for identifying and mapping state and major county roads that prevent residents of RRCs from using AT. They are assessing the specific AT needs, challenges, and perceptions of residents in these communities and are identifying the kinds of infrastructure improvements that would be responsive to local priorities and experiences. They are also developing resources and tools—including a geospatial database, prioritization methodology, and reproducible workflow—to support targeted interventions that WSDOT can implement to improve connectivity, safety, and equitable access for residents of RRCs across the state.

Principal Investigators:
Angela Kitali
Jeff Walters
School of Engineering and Technology, UW Tacoma

Sponsor: WSDOT

WSDOT Technical Monitors:
Grace Young
Brian Wood

WSDOT Project Coordinator: David Strich
Scheduled completion: February 2027

Shore Power: Partnerships to Provide eMobility Options at the Bremerton Ferry Terminal for a Greener Future

Washington State Ferries (WSF) has prioritized electrification as a core strategy to reduce greenhouse gas emissions, improve accessibility, and alleviate congestion at key terminals. This project aims to develop a replicable interagency planning framework for integrating electrified mobility options at ferry terminals. Integrating electric mobility (eMobility) solutions requires a comprehensive approach that includes expanding access to transit, enhancing multimodal travel options, and deploying electrification infrastructure. The Bremerton Ferry Terminal provides a unique opportunity for electrification, given its role as a regional transportation hub with direct connections to Seattle. For this project, researchers are analyzing current mobility challenges, evaluating eMobility and electrification solutions, performing cost analysis and energy demand modeling, creating a scalable planning framework, and engaging stakeholders and facilitating knowledge transfer among WSF, Kitsap Transit, utility providers, and local agencies. The results will support Washington state’s transition to a more resilient, efficient, and equitable transportation system.

Principal Investigators:
Hyun Woo “Chris” Lee, Construction Management, UW
Rachel Berney, Urban Design and Planning, UW
Lingzi Wu, Construction Management, UW
Bart Treece, Mobility Innovation Center

Sponsor: WSDOT
WSDOT Technical Monitor: Kevin Bartoy
WSDOT Project Manager: Mustafa Mohamedali
Scheduled completion: June 2027

Seismic Collapse Prevention for WSDOT Bridges

Earthquakes threaten the functionality and safety of the highway transportation system in Washington state. Given the state’s funding constraints, WSDOT needs to focus scarce resources on the bridge failure mode that is most likely to lead to bridge collapse, namely the shear failure of reinforced concrete columns, and the bridges that are most likely to suffer from column shear failures. This project is developing a new methodology, or modifying an existing one, to evaluate the seismic-shear vulnerability of WSDOT bridges with reinforced-concrete columns. This will allow WSDOT to account for the amount of shear-strength reduction that will result from repeated cycling during long-duration and shorter-duration earthquakes. The researchers will also provide WSDOT with the practical tools and training needed to implement the developed methodology. The results should enable more reliable characterization of post-earthquake transportation functionality, which will support improved emergency planning.

Principal Investigators:
Marc Eberhard, Civil and Environmental Engineering, UW
Jeffrey Berman, Civil and Environmental Engineering, UW

Sponsor: WSDOT
WSDOT Technical Monitor: Amy Leland
WSDOT Project Manager: Mustafa Mohamedali
Scheduled completion: October 2027

Sound Mitigation Study of the SR 520 Bridge Modular Expansion Joints, Phase 3

While expansion joints are a necessary component of bridges, they also contribute to noise pollution. Previous studies have investigated the design and feasibility of strategies to mitigate noise caused by modular expansion joints on bridges in Washington state. This study is Phase 3 of an effort to develop a highly durable sound attenuation system in which researchers will perform laboratory-based testing of noise mitigation prototypes. The prototypes will be injected with mixtures of fiber-reinforced, natural, and synthetic rubber with protective additives. The researchers will use a selection of low-density foam to fill gaps for increased durability and protection against roadway debris. Finally, they will use laboratory equipment to evaluate the prototype systems for hydraulic compression, cyclic fatigue, weathering of the system, adhesive durability, abrasion between the prototype and the seal, and susceptibility to debris.

Principal Investigator: Per Reinhall, Mechanical Engineering, UW
Sponsor: WSDOT
WSDOT Technical Monitor: Omar Jepperson
WSDOT Project Manager: Mustafa Mohamedali
Scheduled completion: November 2026

Pathways for Civil Engineering and Land Surveying Workforce Development in Washington State

Washington state’s ability to deliver infrastructure programs is being constrained by a widening shortage of civil engineers and land surveyors. This study quantified current and future workforce gaps, diagnosed their root causes, and proposed education-centered solutions.

Development of a Specification for Quality Acceptance of Chip Seals Using a Laser Texture Scanner

Chip seals are widely used in Washington state as a cost-effective pavement surfacing method. However, they can be subject to variations in performance and premature failures. This project developed a quality acceptance specification for chip seal construction that incorporates the use of a laser texture scanner to provide valuable, data-driven insights for quality control and performance assessment to enhance the quality and effectiveness of chip seals.

Washington State Rest Area Site Evaluation Study

Washington state has 42 safety rest areas. These rest areas differ in their capacity, facilities, and accessibility in each traffic direction. Some are located at the most traffic-dense corridors such as I-5 and I-90, whereas others are on less traffic-dense state routes. This project provided information on Washington rest area use and user experiences and evaluated the impacts of rest areas on traffic safety.

Ensuring Stream Stability with the Use of Organic Material in a Flume—Design Recommendation

Fish populations in the Pacific Northwest have declined as spawning grounds have disappeared because of river and stream barriers, often under-road culverts. This research investigated ways to incorporate different kinds of organic material inside a culvert that would both maintain the stream channel shape while also improving the ability of fish to successfully navigate those culverts during low water flow.

Equity Analysis of WSDOT’s Toll Program

The Washington State Department of Transportation (WSDOT) uses tolling as a key mechanism for managing demand on I-405, SR 167, SR 99, SR 16, and SR 520 and for funding megaprojects on those facilities. Tolls impose an expense on roadway users, and imposition of these fees can raise concerns about equity. This project provided insight into the use of WSDOT’s toll facilities that is intended to serve as the basis for evaluating the equity implications of those toll facilities.

Maintenance of the Active Transportation Elements of Complete Streets

The need for maintenance of active transportation facilities is relatively new, and the development of consistent levels of service and treatment intervals for all aspects of these facilities is just emerging. This project explored the challenges and opportunities associated with maintaining these facilities, with particular emphasis on lanes that serve bicyclists.

TRAC