Case Studies
Housing Policy, Climate Change, and Health
Community investments, housing codes, and lending practices all affect the built environment in ways that create health risks and protections for individuals as the climate changes.
Redlining practices were implemented by the federal Home Owners’ Loan Corporation (HOLC) to help systematically prioritize long-term mortgage loans during the Great Depression. HOLC long-term mortgage loans were allocated based on maps in which neighborhoods were color-coded according to community characteristics that influenced perceived investment desirability. Areas colored red were often inhabited by Black and immigrant communities and annotated with discriminatory descriptions. These areas were deemed undesirable for investment and ineligible for federally backed loans. Redlining created disparities in the built environment.
Highlights
- Historic and ongoing exclusionary housing policies intensify climate hazards in deadly ways.
- Prioritizing climate vulnerability assessments and adaptation investments in communities with historic redlining could address threat multipliers.
Formerly redlined neighborhoods in New York City include Harlem, the Lower East Side, South Bronx, Bedford-Stuyvesant, and South Jamaica. Across New York State, formerly redlined cities include Syracuse, Albany, and Buffalo (Figure 1). A 2021 study1 showed that historically redlined communities were at a greater risk for flooding, while other studies identified similar risks for urban heat islands.2 The 2021 study also identified that $107 billion worth (8.4%) of homes in redlined areas of the United States were at a high risk of flooding, compared with $85 billion worth (6.9%) of homes in other locations. While Sacramento ranked worst in this practice, New York City followed a close second with $17.5 billion worth (13.8%) of homes in historically redlined areas at high risk of flooding, compared to $4.9 billion worth (7.1%) of homes in other areas.1
Differences in Redlined Cities
Formerly redlined cities are as much as 12.6°F (7°C) hotter than non-redlined cities, according to a spatial analysis that includes nine New York State regions. The difference in temperature is due to a difference in tree canopy and porous surfaces, such as parks and green space.2 Redlining also contributed to disparities in housing quality and increased polluting facilities and infrastructures in Black neighborhoods, which creates higher extreme heat vulnerability.3,4 Although redlining has been banned since 1968, its effects on health persist: redlining has led to persons of color disproportionately living in urban heat islands (Table 1).2,5 In urban heat islands, ambient temperatures are higher than those in surrounding areas due to few trees, high amounts of built materials and waste heat emissions, and urban form that restricts air movement and worsens microclimates.4,6 A recent comparison of HOLC grades in cities across New York State shows up to 8.8°F (4.9°C) difference in land surface temperatures between Grade A neighborhoods and Grade D neighborhoods.2
In addition to elevated temperatures, residents in historically redlined neighborhoods are disproportionately subjected to lower air quality,7 higher risk of preterm births,3 less tree cover and ecosystem services,8 and reduced greenspace.9 The result of these factors and lack of investment in neighborhoods of color has led to a disparity in morbidity and mortality from extreme heat, where Black and African American people in New York City have a higher proportion of heat-related deaths compared to others.10
Current Climate Impacts
Extreme heat is projected to increase in severity, frequency, and duration across New York State. While all residents will be exposed to more extreme heat, the level of exposure is disparate. Recent research has found a causal link between formerly redlined communities and higher current average temperatures. Formerly redlined areas frequently have less tree cover, more impervious surfaces, and fewer park spaces, all of which contribute to increased urban heat island effects and pluvial flooding.2,11,12
| City | D rating – A rating | Persons of color – white | Below poverty – above 2x poverty |
|---|---|---|---|
| Albany | NA | 3.7 | 3.8 |
| Buffalo | 2.9 | 3.9 | 2.6 |
| Elmira | 0.3 | NA | NA |
| New York City | 5.8 | 3.9 | 2.4 |
| Johnson City | 1.9 | NA | NA |
| Niagara Falls | 2.2 | NA | NA |
| Poughkeepsie | 3.5 | 1.8 | 1.7 |
| Rochester | 8.8 | 5.0 | 4.6 |
| Syracuse | 3.9 | 5.2 | 4.6 |
| Utica | 7.3 | NA | NA |
| Average | 4.1 | 3.9 | 3.3 |
Note: HOLC ratings range from A as “best” to D as “hazardous,” the latter of which are areas considered “redlined.” Data from Hoffman et al. (2020).2 “Persons of color” is defined as all Hispanic and all who do not identify as white alone, and “poverty” is based on the American Community Survey’s report of poverty status as household income relative to the poverty line. Data from Hsu et al. (2021).5
Amplifiers
Redlining serves as a proxy for disinvestment in communities of color and amplifies impacts from climate change, which in turn indirectly affects households through greater heat exposure, chronic flooding, and vector-borne disease. These households tend to lack access to coping resources. COVID-19 data across New York State showed that formerly redlined communities suffered a greater impact than others. These hotter neighborhoods also struggle with energy insecurity and poorer housing conditions, including less effective weatherization, which increases energy burden.13,14 Many of these same neighborhoods bore the brunt of subprime mortgages and the threat of foreclosure, which was particularly high after Superstorm Sandy.15
Coping
To cope with these challenges, communities are working with programs such as the National Oceanic and Atmospheric Administration’s HeatWatch to grow community awareness and address the challenges of data justice.16 Some communities are testing cooling strategies that offer multiple benefits, including jobs for community members, conversations about heat risks, and opportunities to improve local microclimates.17 Others are working directly on heat and violence, testing environmental interventions and outcomes and building a shared knowledge base.18–20
Adaptation in Action
New efforts to address structural racism include the federal Justice40 Initiative, the appointment of the New York City Mayor’s Office of Climate and Environmental Justice team, and the Race to Justice report The Impacts of Racism on Health.21 New York State recently recognized racism as a public health crisis, referring to its anchoring in a national pathology that requires healing.22 The New York City Board of Health passed a similar resolution.23,24 The New York Health Foundation defined a number of initiatives focused on racial health equity.25 Efforts such as Undesign the Redline offers workshops and curricula to broaden understanding of the impacts of redlining, including work to undo structural inequities. Resources such as the Health Equity Tracker attempt to visualize ongoing inequities.26 Meanwhile, New York Health and Hospitals launched a coalition to address racism in medical algorithms.27
Moving Forward
Across New York State, climate change vulnerability assessments could be coupled with assessments of environmental inequities using the CEJST and EJScreen tools. Municipalities could prioritize investments by recognizing the amplifying impacts of historic redlining and addressing areas of highest concern that have the greatest threat multipliers. Alongside evaluation of capital investments, community-centered planning could strengthen community risk awareness and improve long-term outcomes.
Sustained efforts to confront the impacts of redlining and dismantle these structures is central to improving New Yorkers’ health.
For More Information
References
1. Katz, L. (2021, March 14). A racist past, a flooded future: Formerly redlined areas have $107 billion worth of homes facing high flood risk—25% more than non-redlined areas. Redfin News. https://www.redfin.com/news/redlining-flood-risk/
2. Hoffman, J. S., Shandas, V., & Pendleton, N. (2020). The effects of historical housing policies on resident exposure to intra-urban heat: A study of 108 US urban areas. Climate, 8(1), 12. https://doi.org/10.3390/cli8010012
3. Krieger, N., Van Wye, G., Huynh, M., Waterman, P. D., Maduro, G., Li, W., Gwynn, R. C., Barbot, O., & Bassett, M. T. (2020). Structural racism, historical redlining, and risk of preterm birth in New York City, 2013–2017. American Journal of Public Health, 110(7), 1046–1053. https://doi.org/10.2105/AJPH.2020.305656
4. U.S. Environmental Protection Agency. (n.d.). Heat islands and equity. Retrieved October 19, 2023, from https://www.epa.gov/heatislands/heat-islands-and-equity
5. Hsu, A., Sheriff, G., Chakraborty, T., & Manya, D. (2021). Disproportionate exposure to urban heat island intensity across major US cities. Nature Communications, 12(1), Article 1. https://doi.org/10.1038/s41467-021-22799-5
6. Stone Jr., B., Lanza, K., Mallen, E., Vargo, J., & Russell, A. (2019). Urban heat management in Louisville, Kentucky: A framework for climate adaptation planning. Journal of Planning Education and Research, 43(2). https://doi.org/10.1177/0739456X19879214
7. Lane, H. M., Morello-Frosch, R., Marshall, J. D., & Apte, J. S. (2022). Historical redlining is associated with present-day air pollution disparities in U.S. cities. Environmental Science & Technology Letters, acs.estlett.1c01012. https://doi.org/10.1021/acs.estlett.1c01012
8. Nowak, D. J., Ellis, A., & Greenfield, E. J. (2022). The disparity in tree cover and ecosystem service values among redlining classes in the United States. Landscape and Urban Planning, 221, 104370. https://doi.org/10.1016/j.landurbplan.2022.104370
9. Nardone, A., Rudolph, K. E., Morello-Frosch, R., & Casey, J. A. (2021). Redlines and greenspace: The relationship between historical redlining and 2010 greenspace across the United States. Environmental Health Perspectives, 129(1), 017006. https://doi.org/10.1289/EHP7495
10. City of New York. (2023). 2023 NYC heat-related mortality report summary. Environment and Health Data Portal. Retrieved November 21, 2023, from https://a816-dohbesp.nyc.gov/IndicatorPublic/beta/key-topics/climatehealth/heat-report/
11. Capps, K., & Cannon, C. (2021). Redlined, now flooding. Bloomberg. Retrieved November 8, 2022, from https://www.bloomberg.com/graphics/2021-flood-risk-redlining/
12. National Low Income Housing Coalition. (2021, March 22). New study finds historically redlined communities at a higher risk of flooding. Retrieved May 13, 2022, from https://nlihc.org/resource/new-study-finds-historically-redlined-communities-higher-risk-flooding
13. Plumer, B., Popovich, N., & Palmer, B. (2020, August 24). How decades of racist housing policy left neighborhoods sweltering. The New York Times. https://www.nytimes.com/interactive/2020/08/24/climate/racism-redlining-cities-global-warming.html
14. U.S. Department of Housing and Urban Development. (2024). Severe housing problems in New York. America’s Health Rankings. Retrieved October 18, 2022, from https://www.americashealthrankings.org/explore/annual/measure/severe_housing_problems/state/NY
15. Romeo, F., & Ching, J. (n.d.). Homes underwater: Forbearance alternatives for Sandy-affected homeowners. Queens Legal Services, Legal Services NYC. https://www.legalservicesnyc.org/storage/PDFs/homes%20underwater%20forbearance%20alternatives%20for%20sandy%20homeowners.pdf
16. National Integrated Heat Health Information System. (n.d.). Mapping campaigns. HEAT.gov. Retrieved August 24, 2022, from https://www.heat.gov/pages/mapping-campaigns
17. Philadelphia Office of Sustainability. (n.d.). Beat the heat Hunting Park: A community heat relief plan. https://www.phila.gov/media/20190719092954/HP_R8print-1.pdf
18. South, E. C. (2021, October 8). To combat gun violence, clean up the neighborhood. The New York Times. https://www.nytimes.com/2021/10/08/opinion/gun-violence-biden-philadelphia.html
19. Kondo, M. C., South, E. C., Branas, C. C., Richmond, T. S., & Wiebe, D. J. (2017). The association between urban tree cover and gun assault: A case-control and case-crossover study. American Journal of Epidemiology, 186(3), 289–296. https://doi.org/10.1093/aje/kwx096
20. Moore, T. H. M., Kesten, J. M., López-López, J. A., Ijaz, S., McAleenan, A., Richards, A., Gray, S., Savović, J., & Audrey, S. (2018). The effects of changes to the built environment on the mental health and well-being of adults: Systematic review. Health & Place, 53, 237–257. https://doi.org/10.1016/j.healthplace.2018.07.012
21. City of New York. (n.d.). The impacts of racism on health. Race to Justice. https://www1.nyc.gov/assets/doh/downloads/pdf/dpho/race-to-justice-action-kit-impacts-of-racism-on-health.pdf
22. New York State Department of Health. (2022, April 4). Statement from New York State Health Commissioner Dr. Mary T. Bassett as National Public Health Week begins with a spotlight on racism: A public health crisis. Retrieved November 8, 2022, from https://health.ny.gov/press/releases/2022/2022-04-04_commissioner_national_health_week.htm
23. New York City Department of Health and Mental Hygeine. (2021). Board of Health passes resolution declaring racism a public health crisis. https://www.nyc.gov/site/doh/about/press/pr2021/board-of-health-declares-racism-public-health-crisis.page
24. New York City Board of Health. (2021, October 18). Resolution of the NYC Board of Health declaring racism a public health crisis. Retrieved November 2, 2022, from https://www.nyc.gov/assets/doh/downloads/pdf/boh/racism-public-health-crisis-resolution.pdf
25. New York Health Foundation. (2020). Pursuing racial health equity. Retrieved November 8, 2022, from https://nyhealthfoundation.org/grantee-story/pursuing-racial-health-equity/
26. Satcher Health Leadership Institute, Morehouse School of Medicine. (n.d.). Health equity tracker. Retrieved November 8, 2022, from https://healthequitytracker.org
27. NYC Health + Hospitals. (n.d.). Health Department launches coalition to confront racism in medical algorithms. Retrieved November 8, 2022, from https://www.nychealthandhospitals.org/pressrelease/health-department-launches-coalition-to-confront-racism-in-medical-algorithms/