Publications

Summary:
In Spring 2023, the Seattle Department of Transportation (SDOT) was awarded a Stage-1 grant under the Strengthening Mobility and Revolutionizing Transportation (SMART) Grants Program by the US DOT.

Summary:
Evaluating health equity impacts of freight emissions is crucial for developing a sustainable and just freight system. It is a complex process that requires interdisciplinary knowledge, including transportation, environment, and public health. Full-chain simulation is an important approach for forecasting freight planning outcomes. However, a systematic framework that integrates available models in full-chain and is specifically designed for the freight sector has not been developed.

Summary:
New research from the Urban Freight Lab outlines how U.S. cities can advance zero-emission freight goals despite legal and regulatory barriers that limit the use of formal Zero- and Low-Emission Zones. The paper presents a practical four-part toolkit that combines incentive-based “pull” strategies with regulatory “push” tools, supported by real-world examples from cities including Portland, Washington, D.C., New Orleans, and New York.

Summary:
As freight demand grows, so do its negative externalities, such as health and environmental impacts. This study integrates a reduced-complexity air quality model (RCM) with a multimodal traffic assignment model to analyze the scenario in which trucks minimize their public health costs. The study compares the least health-cost path (LHCP) with the shortest, fastest, and least-emissions paths.

Summary:
Globalized production and the expansion of e-commerce have intensified urban road freight demand, exacerbating environmental impacts of cities and potential equity concerns across cities. These challenges have hindered progress toward Sustainable Development Goals 3, 10 and 11, yet long-term spatial trends remain understudied.

Summary:
Inefficient curb space allocation increases congestion and emissions at airports. Variable message signs (VMS) can alleviate this issue, guiding vehicles from congested to underutilized curbs. However, VMS effectiveness hinges on the right activation and deactivation timing. Using a microsimulation model of the Seattle-Tacoma International Airport, we analyzed the impacts of implementing VMS and determined the best time to turn the sign on and off.

Summary:
As e-commerce and urban deliveries spike, there is an increasing demand for curbside loading/unloading space. However, commercial vehicle drivers face numerous challenges while navigating dense urban road networks. These challenges can lead to conflicts with other road users, congestion, illegal parking, and parking time violations.

Summary:
For this report, new mobility services are defined as innovative transportation services that redefine how people and goods move within the existing transportation system. Examples include micromobility (shared bikes and scooters), car-sharing, ride-hailing, microtransit, and modern goods delivery services. Revenue measures applied to new mobility services can help agencies that own and manage the transportation system fund staff, technology improvements, and right-of-way modifications.

Summary:
The rapid growth of commercial vehicle traffic in urban areas has increased competition for limited curb space, prompting cities to implement curb management strategies targeting freight transport demand. A Commercial Vehicle Load Zone (CVLZ) program is defined as a collection of infrastructure, policy, and regulatory strategies adopted by public agencies to manage commercial vehicle access and facilitate loading/unloading and provision of services in urban areas.

Summary:
Populations of color (POC) are disproportionately exposed to delivery-related traffic despite ordering fewer packages than White populations. This study uses structural equation modeling (SEM) to examine which urban form and socio-economic factors contribute to these racial disparities in 39 U.S. metropolitan statistical areas (MSAs). Of particular interest is “logistics sprawl,” which has lengthened distances between freight supply and demand.

Summary:
E-commerce is transforming urban freight systems and creating challenges for last-mile delivery due to fragmented demand, high stop density, and diverse delivery models. This study examines last-mile e-commerce delivery in five cities, primarily focusing on parcel deliveries, and analyzes how the state of practice of last-mile delivery systems is influenced by local contexts, including urban development, planning and policy, and market structures.

Summary:
The Seattle SMART Grant Digital Commercial Vehicle Permit Project advanced work to provide reliable, modern curb access for commercial delivery vehicles using a collaborative, data driven approach.