Students for Urban Data Systems

at Carnegie Mellon University

The Legacies of Redlining in Pittsburgh


by Devin Rutan

Pittsburgh is still defined by a geography of uneven development where modern disparities were built from historic patterns of discrimination. While searching through PghSNAP, I was struck by the similarities between the survey of prevailing building conditions and the Home Owners Loan Corporation (HOLC) map of 1937. So, I created a GIS-based framework to assess the legacies of neighborhood appraisal and lending discrimination in Pittsburgh by intersecting the HOLC map with census data.

1 & 2

Current building conditions & 1937 Home Owners Lending Corporation (HOLC) divisions

Before getting swept up in the analysis, I want to be clear about what the HOLC map is and what it represents, so in the interest of brevity, I have highlighted some of the key aspects of the history. For a more thorough (perhaps too thorough) version you can read the full paper: here.

In the 1930’s, the federal government fundamentally transformed the mortgage market, creating the 30 year mortgage packages that make home-ownership accessible. In an effort to address perceived weaknesses in the housing market, federal officials advocated more ‘scientific’ appraisal methods. Appraisal ideology was forged within a climate of prejudice generally pervasive throughout white society, explicit institutional discrimination at most levels of government throughout the United States, and a heavily skewed distribution of economic power; policy makers saw little value in poor, African-American, immigrant, or Jewish communities and even viewed them as a direct threat to the value of middle class, white communities.

The maps are terrific localized representations of appraisal practices in each of the 239 cities they depicted. The HOLC maps were not directly published and used by bankers and appraisers to make lending decisions but were, nonetheless, certainly influential in the development of biased appraisals: the federal government published the tools, rationales, and examples necessary for banks to create maps of their own.

The first portion of my investigation tried to understand more about the impact of these practices at the time they were being honed. I intersected the 1940 Census, obtained from NHGIS, with the HOLC map. One of the strongest relationships within the appraisal of Pittsburgh neighborhoods was racial segregation. In the graph below, I arranged the communities by their HOLC ranking and then plotted the percentage of white residents in the tract (at this time, Pittsburgh had virtually only two racial groups). Looking at the four plots together, it is clear that a huge portion of Pittsburgh, regardless of value, was exclusively white. The dashed blue line represents the overall percentage of white people in Pittsburgh at the time; if communities were not segregated by race, they would hover around this line. Now consider the valuation of the tracts: not only were African Americans concentrated into a handful of places but they were relegated the lowest quality neighborhoods that were considered to be the least valuable (partially because of their presence). Also, a methodological aside, because census tracts encompass an aggregated area, segregation at the block level could only be starker.


Next, I explored how these historic practices have continued to shape Pittsburgh. I used standardized census data to identify entrenched neighborhood characteristics from 1970 to 2000. Tracts that persistently had the largest proportions of African Americans were almost entirely aligned with red and yellow areas as you can see in the map below. Three main clusters of African American residents appeared: the Hill District, Manchester, and Homewood. These are communities that were historically considered the least valuable and were undermined economically and are, at least in part, still dealing with the effects. Further, tracts that persistently had the highest concentrations of poverty were also heavily focused in red and yellow areas. Red and yellow tracts were also much more susceptible to population loss than green or blue areas as you can see in the graph below. In many ways these spaces have held their position through time and the access, or lack of access, to mortgage financing had long reaching legacies. Groups that historically were victimized by appraisal ideology continue to occupy these spaces. These neighborhoods are likely less stable as well, considering the large presence of poverty and heaviest population losses.


Black communities have suffered from disinvestment


Pittsburgh’s uneven decline in population, 1970-2000

On the other hand, those communities that were uplifted by their historic value largely retained their status into modern times. Tracts with persistently the highest average incomes, home-ownership rates, even for African Americans, and the highest average values were all largely aligned with the historic green or blue categorizations. These communities benefited from unfettered access to the mortgage market and became the most stable, affluent neighborhoods in Pittsburgh because of their relative health. As you can see in the map for highest average values, Squirrel Hill, in particular, maintained its position. The disproportionate access to mortgage funds even continues today: according to PCRG, 7 neighborhoods received 50% of all mortgage dollars in 2015—6 of the 7 were historically rated either green or blue.


Wealthy communities benefited from redlining

What is clear from the assessment of Pittsburgh’s geographic legacies of redlining is that the city is still largely defined by an ugly history of uneven development. As much as we may like to think that we have moved beyond pre-World War 2 or pre-Civil Rights Pittsburgh, we live in a city that is still, at least somewhat, constructed the same way. Policies that have attempted to create equality and opportunity for parts of the city that were left behind have failed to do so. Those parts of the city that were built on their exclusion have maintained their privileged and elevated status. Today, as we are having debates about neighborhood quality, accessibility, and inclusion, we must remember the specific history of uneven development. Are we comfortable with this geography? If not, what are we willing to do, lest it define us for another 60 years?


Devin Rutan graduated from the University of Pittsburgh with a Bachelors of Philosophy in Urban Studies and studied Applied Statistics and GIS. Devin cares about housing and neighborhood development and is currently working with the Northside Coalition for Fair Housing and the Pittsburgh Tenants Union. Originally from the DC area, Devin is an avid basketball fan: Let’s go Wizards! You can follow his work here or connect with Devin here:


  1. Very interesting work, Devin!

  2. This is very interesting. I’ve never seen maps of this detail on redlining. This is why lending institutions were founded that catered to blacks, and various ethnic groups. Even ethnic insurance federations were founded. In Homestead there was Slovak Savings, now Great American. In Sq Hill Franklin Federal. In Lawrenceville, Stanton Federal. Then there was the “women issue” Banks would generally not lend to women, even in the 70’s. The law even categorized them differently in buying real estate without a husband. They were classified a sole femme trader. It would be interesting to see a study on the chilling effects and problems women had without access to the credit markets.

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