Development of a Heavy-Duty Vehicle Emissions Inventory with High Spatial Resolution for Community-Level Analysis

Vehicle emissions have been a major contributor to air pollution in California, and despite progress in reducing emissions, there are still equity concerns for certain populations, such as those living in disadvantaged communities (DACs). This study introduces a high-resolution heavy-duty vehicle (HDV) emissions inventory that integrates newly available telematics-based activity data with EMFAC, California’s official on-road emissions inventory model. The study reveals disparities in emissions from HDVs. On average, the statewide NOx emission flux in 2022 was 4.07, which was 3.05 in non-DACs, and was 7.36 in DACs (all in units of tons NOx·year–1·mi–2). Similarly, the average statewide PM2.5 emission flux was 0.039, which was 0.029 in non-DACs, and was 0.069 in DACs (tons PM2.5·year–1·mi–2). NOx and PM2.5 emission fluxes were also disproportionately higher in Hispanic-dominated communities compared to those in communities dominated by any other racial group. Additionally, analysis of drayage truck routes shows a clear spatial overlap with DACs. This data-driven inventory serves as a new valuable tool for policymakers to identify and address environmental inequities.