A new study finds that 15% of urban neighborhoods across America show signs of gentrification over the last 50 years, with the number of gentrifying urban neighborhoods growing sevenfold from 1970 through 2020. And that gentrification comes at a high price for Black communities.

While gentrification is still relatively uncommon, the National Community Reinvestment Coalition’s new “Displaced By Design” report concludes, its harms can be intense and lasting – namely displacement of disinvested communities.

From 1980 to 2020, gentrification impacted more than 1,800 downtown census tracts in major metro areas, with Washington, DC, New York City, Philadelphia, New Orleans, Atlanta and the San Francisco Bay area topping the list.

The list includes more than 500 mostly-Black neighborhoods affected by gentrification, researchers found. Nearly half of mostly-Black neighborhoods that experienced gentrification in 1980 were no longer mostly-Black by 2020; of those, about 29% saw a full racial turnover and became mostly white or Hispanic neighborhoods, and about 23% became racially-mixed.

In total, the data indicates a loss of half a million Black residents in all gentrifying neighborhoods between 1980 and 2020.

“So that’s the level of displacement that we’re seeing occurring, and it can be quite concentrated in some cities,” lead researcher Bruce Mitchell says. He goes on to explain that, “the resegregation is something that we’re concerned about, and the loss of affordability, too.”

Gentrification can be difficult to define and even harder to measure. In addition to analyzing changes in income, home values and college education levels, the study added an additional validation method. Researchers gauged changes in social class by tracking differences in professional, technical and managerial employment; in the racial and ethnic composition of neighborhoods; and in mortgage lending activity.

While the public often imagines gentrification as individuals flipping homes for profit, Mitchell emphasizes that this study is focused on developer-driven and urban planning-driven gentrification that can lead to widespread unaffordability and displacement.

Such revitalization efforts can be necessary to bring services, amenities and infrastructure to disinvested neighborhoods, and it can also increase a city’s taxbase. But researchers note that longtime residents often only see the negative consequences of these investments. Instead, it’s the influx of newcomers – often higher-income white residents who are able to afford the resulting higher cost of living – who reap the benefits.

With an ongoing national housing shortage continuing to drive gentrification, researchers say, it’s crucial for urban planners and policymakers planning urban redevelopment initiatives to proactively minimize these harms with community-led development, affordable housing preservation, homestead exemptions on property taxes, and other strategies.

“What we want to see is that these negative effects are minimized as much as possible, so that incumbent residents in that neighborhood can enjoy the benefits of an improved neighborhood and services,” Mitchell says.

This post was originally published on Next City.