I-45 Expansion: Health Impact Assessment and Community Organizing
As currently designed, the Texas Department of Transportation’s (TxDOT) I-45 expansion, known as the North Houston Highway Improvement Project (NHHIP), could cost Houston in terms of air quality, mobility, resilience, climate change mitigation, and social equity, perpetuating the legacy of environmental injustices and related health inequities. If done right, this project is an opportunity to demonstrate that our region is committed to moving toward more thoughtful transportation planning.

Benzene emissions are projected to increase by as much as 175% at some school locations because of emissions from the highway expansion.
What We're Doing
A Health Impact Assessment and a Civil rights complaint against discriminatory actions by TxDOT
In spring 2018, we were funded by the Urban Institute and the Robert Wood Johnson Foundation under the 500 Cities Data Challenge to conduct a Health Impact Assessment (HIA) of the NHHIP. The assessment focused on potential air quality, mobility, and flooding impacts at nine priority school campuses along the I-45 corridor.
In January 2021 in conjunction with partner communities and organizations, we filed two legal complaints against TxDOT under Title VI of the Civil Rights Act of 1964. As currently designed, the NHHIP would displace residents in over 1,000 households and hundreds of businesses in communities adjacent to the I-45 corridor, mostly in low-income areas.
The Federal Highway Administration (FHWA) has ordered a pause of the project to investigate these and other potential civil rights violations. We continue to work alongside Houstonians to make sure community concerns surrounding the project are addressed.
If mitigative strategies are not put in place, children and the surrounding communities may experience increased exposure to harmful air pollution, face more traffic safety concerns, and have to deal with aggravated flooding risks.
- See here for a summary of the key findings and recommendations.
- Read here the full Health Impact Assessment Report.
- A comprehensive overview of the HIA and all final products are available on the Urban Institute’s “Putting Local Data to Work” site.
Continuing Health Impact Assessments
We are working with Urban Design 4 Health, Inc. to create a Houston-specific Public Health Assessment Model (H-PHAM) that will be used to estimate the health impacts and economic implications for a broad array of transportation and land use policies and projects. The tool will pay particular attention to the impacts to disadvantaged communities. We will use the findings to guide our advocacy for needed transportation reform in Texas.
Our Health Impact Assessment of the NHHIP:
Air Alliance Houston: Health Impact Assessment of the North Houston Highway Improvement Project
Air Alliance Houston: Health Assessment of The Bruce Elementary School Community – Final Report
Air Alliance Houston: I-45 N Expansion Health Impact Assessment – Summary of Key Findings
Air Alliance Houston: I-45 N Expansion Health Impact Assessment – Concerns, Impacts, Possible Solutions
Air Alliance Houston: North Houston Highway Improvement Project (NHHIP) Health Impact Assessment – 3rd Ward/Midtown/Museum District Recommendations
Air Alliance Houston: North Houston Highway Improvement Project (NHHIP) Health Impact Assessment – 5th Ward Recommendations
Air Alliance Houston: North Houston Highway Improvement Project (NHHIP) Health Impact Assessment – Greater Northside/Northline Recommendations
Air Alliance Houston: Proyecto del Mejoramiento de la Autopista del Norte de Houston y Evaluación del Impacto en la Salud (NHHIP por sus siglas en Inglés) – Recomendaciones para Greater Northside/Northline
Air Alliance Houston: North Houston Highway Improvement Project (NHHIP) Health Impact Assessment – Aldine/Greenspoint Recommendations
Air Alliance Houston: Proyecto del Mejoramiento de la Autopista del Norte de Houston y Evaluación del Impacto en la Salud (NHHIP por sus siglas en Inglés) – Recomendaciones para Aldine/Greenspoint
City of Houston documentation:
City of Houston’s interactive map about the project’s impacts
From our partners:
Make I-45 Better Coalition – documents