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Legacy segregation

Washington, D.C.

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Rapidly integrated

Since 1990, more than 90 percent of U.S. metro areas have seen a decline in racial stratification, signaling a trend toward a more integrated America. Yet, while areas like Houston and Atlanta have undergone rapid demographic changes, cities like Detroit and Chicago still have large areas dominated by a single racial group.

Some 50 years ago, policies like the Fair Housing Act and the Voting Rights Act were enacted to increase integration, promote equity, combat discrimination and dismantle the lingering legacy of Jim Crow laws. But a Washington Post analysis shows that some cities remain deeply segregated — even as the country itself becomes more diverse.

To explore these national changes, The Post analyzed census data from 1990, 2000, 2010 and the latest estimates from the 2016 five-year American Community Survey. Using that data, we generated detailed maps of the United States using six race categories: black, white, Hispanic, Asian/Pacific Islander, Native American and multi-race/other for the available years.

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To calculate diversity, we used what's called the entropy index, which measures the spatial distribution of race in a given area. The more clustered together a single racial group is, the less diverse that area is. If the group is distributed evenly, then the area is considered more diverse.

Diversity beyond the city

Over the past 30 years, suburbs have increasingly become the most racial and ethnically diverse areas in the country. For example, the D.C. metro area saw the Hispanic American population increase by almost 300 percent from 1990 to 2016. The Asian American population increased by 200 percent within the same period.

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Suburbs such as Annandale, Va., and Silver Spring, Md., showed large increases in racial ethnic diversity compared with about three decades ago.

Michael Bader, an assistant professor of sociology at American University in the District, attributes part of suburban diversity to newly built housing.

"A lot of those areas were developed after the Fair Housing Act was implemented," he said. "If you're building housing and you're subject to the Fair Housing Act, you shouldn't have, in those particular units, the legacy effects of segregation."

He also noted that rental and purchase prices in the suburbs tend to be lower than in cities, offering more opportunities for a diverse population, both in race and income level, to move in.

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Houston is another city that has seen large growth in its Asian and Hispanic American populations. The metro area saw a more than 200 percent increase in both populations from 1990 to 2016.

Lasting segregation

Despite the District's diverse suburbs, areas east of the Anacostia River remain largely inhabited by African Americans.

And while the Anacostia neighborhood and Southeast D.C. are home to some of the region's poorest families, Prince George's County in Maryland, just east of the District, is home to some of the wealthiest. Several neighborhoods in the county were ranked as the wealthiest black communities in the country.

"What's interesting about P.G. County," Bader said, "is that it was white in the '70s and '80s. As the black middle class moved in, the white middle class stopped moving in."

Persistent and deep segregation is somewhat unique to African Americans, Bader said, for several reasons: the legacy of segregated neighborhoods created during the era of Reconstruction and Jim Crow; enduring racial preferences among whites who choose to live near other white people; and significant Latino and Asian immigration after fair housing laws were in place.

This deep segregation is noticeable in cities with large African American populations.

Chicago, for example, shows how persistent segregation can be, even for a city with a diverse population.

The South and West sides of Chicago are starkly African American, while other areas remain starkly Hispanic or white.

The Chicago metropolitan area has remained one of the most segregated regions in the United States since 1990. Detroit, another largely African American city, has remained the most segregated metropolitan area since 1990.

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Why segregation persist

Since 1990, a majority of U.S. metro areas have seen increases in racial diversity. While this means that more Americans are living in diverse neighborhoods, the numbers are still lower than researchers anticipated.

"There have been declines [in segregation], but they just haven't been as fast as we would expect," said Kyle Crowder, a professor of sociology at the University of Washington. He and Maria Krysan, a professor of sociology at the University of Illinois at Chicago, recently published their research on residential stratification in a book titled "Cycle of Segregation."

In the book, they argue that although segregation is generally decreasing, factors such as social networks and communities play a large role in keeping segregation embedded in American life.

Decades of scholarship point to three main reasons for persistent segregation: money, preferences and discrimination. But, to Crowder and Krysan, the answer is more complex.

"The separation of different racial and ethnic groups into separate social worlds means that members of different racial and ethnic groups have different lived experiences," Crowder said. "They have different daily rounds. They're exposed to different neighborhoods on a daily basis. Residential segregation has separated these groups by educational quality and occupational opportunity."

That could explain, for example, why a city like Chicago has a diverse mix of racial and ethnic groups that remain in specific parts of the city. Research on residential segregation often points to the discriminatory practices — like "redlining" — that placed specific racial groups in specific parts of the city. But Krysan argues that it goes deeper than that.

"We don't have the integrated social networks. We don't have integrated experiences through the city. It's baked-in segregation," Krysan said. Every time someone makes a move, she said, they're "not making a move that breaks out of that cycle, and making a move that regenerates it."

How integrated is your city?

Dan Keating, Ted Mellnik and Laris Karklis contributed to this report.

About this story

Race and ethnicity data for all years comes from the U.S. census. The 2016 figures are estimates from the five-year 2012-2016 American Community Survey. Population counts were determined from census block groups, which are clusters of census blocks that contain between 600 and 3,000 people and never cross state or county boundaries.

Black, Asian, Native, other race and white data excludes anyone with Hispanic ethnicity since any race can have Hispanic origin in the census. "Other" includes multi-racial and other race census categories. Asian includes Asian, Native Hawaiian and other Pacific Islander.

This analysis uses the multigroup entropy index (sometimes referred to as the Theil index) to measure how integrated a city or region is. The index is a statistical measure that determines how uniform the ethnic distribution is for a given area. A region that is closer to zero (green on the map) has a more even distribution of race and ethnic groups, meaning the area is more integrated than segregated.

All data was normalized to use the 2010 Census block group shapes. All population locations are random and are not exact locations of people in a region but rather the total number of people of that race in a block group. Some group blocks extend into water and we've made an effort to limit the number of dots visualized over bodies of water.

The project analysis was done mostly in node.js with some work in PostGIS. While several technologies were used in this project, special thanks goes to Mapbox's helpful suite of tools and d3.js.

Originally published May 2, 2018.