North Carolina Clean Transportation Study

Abstract

This study estimated the distributional impacts of the ACT rule by modeling the expected change in roadway emissions using spatially explicit data on current and projected MHD traffic volumes and overlaying this model with community-based sociodemographic data. This modeling exercise allowed us to estimate the distributional impacts of ACT on local North Carolina communities.
Our findings show that the greatest ACT primary pollution reductions accrue to near-road communities that are subjected to higher concentrations of air pollutants from vehicle traffic. Furthermore, we found that low-income households tend to be overrepresented in these near-road communities. As a result, we conclude that these communities receive a disproportionate level of pollution reduction. The reduction in pollution concentrations in these communities is expected to provide significant health benefits and significant health cost savings over the next 25 to 30 years.
We found that the ACT rule is expected to result in significant reductions in NOx and PM2.5 over the next 25 years, and communities in the 11-county study area will experience a steady decline in emissions, culminating in a 61% reduction in NOx and a 73% reduction in PM2.5 from baseline emissions in 2050. Perhaps more importantly, approximately 42% of emission reductions are concentrated in some of the most vulnerable communities, defined in terms of race, income, and education. Based on the strong body of evidence in the public health and air quality literature, we know that these emission reductions will yield health benefits such as reduced mortality and hospitalization related to respiratory illness for the people living in these communities.