Prove your humanity

Greenspace in cities gives people places to exercise. It’s good for mental health, and studies have shown that greenspace can help urban areas stay cooler during heatwaves. But a new study published in the journal Environmental Health Perspectives shows that across the United States, many neighborhoods lack greenspace today because of a specific government policy called redlining which was enacted over 80 years ago.

The study is called Red Lines and Greenspace: The Relationship between Historical Redlining and 2010 Greenspace across the United States.

Kara Holsopple talked with one of the authors of the study, Rachel Morello-Frosch, Ph.D., M.P.H., a professor in the Department of Environmental Science, Policy and Management & the School of Public Health at the University of California, Berkeley.

The conversation has been edited for clarity

LISTEN to their conversation: 

Kara Holsopple: Can you explain the practice of redlining and how it impacted communities? 

Rachel Morello-Frosch: Redlining is a term that came from a federal policy in the 1930s under Roosevelt’s New Deal. During the Great Depression, an agency called the Homeowner Loan Corporation was charged with helping communities, particularly in cities. It was a recovery program, and the government was charged with grading neighborhoods in communities across the country based on their financial risk and whether or not they would be given mortgage insurance policies to prevent mortgage bailouts. 

Essentially, there were four grades: green, blue, yellow and red, and several of the criteria were based on the racial and ethnic makeup of neighborhoods. The higher proportion of residents of color, the worse the grade was for the neighborhood. If it was considered high risk, it was given a red-colored grade, ergo the term redlining. So this basically dictated the extent to which those communities would have access to capital to enhance and preserve rates of homeownership in the 1930s. 

Holsopple: And that’s had repercussions all the way up to today?

Morello-Frosch: Absolutely. There’s been some good work to show that a racist policy that was enacted over 80 years ago still exerts its effects on the socio-economic and environmental profiles of these neighborhoods. Many of these redlined neighborhoods are still disproportionately low to moderate-income, with very high proportions of residents of color. Now that more of us are starting to do studies on these neighborhoods, we’re seeing its effects on the physical environment, as well as in the health status of the communities that were historically redlined. We still see those effects today. 

Holsopple: So what did this study set out to look at? 

Morello-Frosch: This study specifically sought to look at the disparities in greenspace coverage based on the historical grades of these neighborhoods. We looked at satellite imagery that allows us to look at greenspace coverage across the country. It’s a very nice data set. What we found essentially is that the redlined neighborhoods had the least amount of greenspace coverage, even after accounting for a lot of other factors that might explain that relationship.

Holsopple: What do you mean when you say greenspace?

Morello-Frosch:  Greenspace can be a lot of different things. We tend to think about greenspace as our local parks, but it can also include things like tree canopy in your neighborhood; the extent to which you have greenery when you walk out on the street; open space. 

One of the issues with this data is that it doesn’t always distinguish between certain types of greenspace within a neighborhood — unmaintained parcels, for example. That’s a little bit of a shortcoming of the data. But it does give you a really good sense of the extent to which there is greenspace in particular neighborhoods, which generally includes desirable greenspace. 

Holsopple: Part of the data that you looked at was 1940 census data. 

Morello-Frosch: Yes, we wanted to be able to account for the fact that there were a lot of socio-economic factors in the 1940s that could also be affecting access to greenspace today. We wanted to be able to account for that so that we could isolate the fact that this federal government policy is really driving the patterns that we’re seeing in greenspace today. 

Study: Redlining Intensifies the Impact of Climate Change in Urban Areas

Holsopple: How does this work build on other studies that have been done about redlining? 

Morello-Frosch: It’s interesting because in the field of sociology, people have been looking at the effects of redlining on the social and current economic opportunities of communities today. But more recently, people in the field of environmental science have been able to think about structural drivers of environmental health disparities in the United States in new ways, in part because of the release of these digitized Homeowners Loan Corporation risk grade maps. We also have looked at the relationship between risk of asthma exacerbations and redlining, and found very strong relationships. And we’ve looked at the relationship between redlining and the risk of poor birth outcomes in cities in California, where we were able to get digitized birth records. 

Holsopple: And there are other environmental hazards and impacts that are associated with historically redlined areas? 

Morello-Frosch: Yes. We know that redlined areas historically have had fewer investments in their physical infrastructure. Historically, many redlined neighborhoods were zoned for lots of industrial development, like hazardous facilities that pollute. Many of these redlined neighborhoods had their communities cut up by major roadways and freeways, which have exposed them to traffic-related air pollution and other environmental hazards. Redlining continues to exert and disproportionately expose the communities that live in them today to different kinds of environmental hazards. 

Holsopple: How do you hope your study could be used? 

Morello-Frosch: I think studies like this can really lift up opportunities for where we want to be directing investments and interventions to improve the physical and social environments in these redlined neighborhoods and start the process of making spatial reparations, if you will, to improve and protect these vulnerable groups. 

Holsopple: Thank you so much for talking with me. 

Morello-Frosch: Thank you so much. My pleasure. 


Photo (top): Greg Blick / Flickr