Transportation Equity Project Research Update

March 2, 2021

The Transportation, Equity, Climate & Health (TRECH) research team has updated their preliminary results, which estimate changes in health outcomes from active mobility (e.g., biking and walking) and air quality in 2032 assuming all 12 Northeast and Mid-Atlantic states and the District of Columbia participate in the Transportation Climate Initiative (TCI).

The TRECH Project is a multi-university research initiative conducting an independent analysis of policy scenarios to address carbon pollution from the transportation sector. The project looks at changes in health outcomes from active mobility and air quality using published, peer-reviewed models commonly employed in regulatory analysis.

Researchers at the Columbia Center for Children’s Environmental Health at Columbia University Mailman School of Public Health, Harvard T.H. Chan School of Public Health, Boston University, and the University of North Carolina are making their updated preliminary results available as states and stakeholders are considering how best to design and implement state transportation plans to achieve health and equity benefits. Details are published online

Key Takeaways

  • Assuming all Northeast and Mid-Atlantic states and D.C. participate in TCI, the estimated health benefits under the five regional TCI climate policy scenarios analyzed are substantial and are larger than estimated TCI program proceeds, for a subset of total possible benefits.

  • The TCI policy scenario with the largest estimated health benefits has the most ambitious emissions reduction cap and the largest share of investments dedicated to public transit and active mobility.

  • Under all five policy scenarios, health benefits are estimated to occur in all counties across the region and are concentrated in more populated areas.

  • All five policy scenarios modestly reduce inequities in air pollution exposure between racial/ethnic groups, but even with the reductions estimated under the TCI policy scenarios, people of color would still face higher overall air pollution exposures and more emission reductions would be needed to address these pre-existing inequities.

  • The four-fold difference in the estimated health benefits exists across the five TCI policy scenarios, underscoring that there is a wide range of possible health outcomes and that actual health benefits will depend on state participation and state actions.

The TRECH project results now account for the full effect of changes in nitrogen dioxide emissions from on-road transportation sources and incorporate estimates of childhood asthma incidences and exacerbations. Based on these updates, the estimated benefits of the health outcomes studied are $13.5 billion in 2032 for the top-performing scenario, up from $11.1 billion when the researchers initially released their estimate last October.