Today we’re witnessing the rise of a new urban phenomenon: the segregated affluent neighborhood. These aren’t gated communities or condo high rises. They are isolated, rich neighborhoods that arise, seemingly spontaneously, from the shifting real estate in city centers. Armed with new data sets and computer-generated models, two urban planning researchers at UCLA have figured out where these enclaves come from and how they are changing our cities.
Income segregated neighborhoods
Urban planning professors Michael C. Lens and Paavo Monkkonen published the results of their research this month in the Journal of the American Planning Association after an intensive analysis of new data on the 95 biggest cities in the United States. Though it’s widely known that income inequality has risen in US cities over the past 40 years, very little research has been done on how this affects neighborhoods. Most researchers assumed that income inequality led to segregated poor neighborhoods, or ghettos. But Lens and Monkkonen found it actually led to the opposite: enclaves of the ultra-rich.
Of course, cities have always had rich and poor neighborhoods. What’s shrinking out of existence today are mixed neighborhoods that include people from different class and cultural backgrounds. And that’s a problem, say economists who have done longitudinal studies of kids who grow up in income segregated cities. Kids who grow up in neighborhoods where everyone is poor tend to stay poor, while kids in mixed neighborhoods enjoy the kind of class mobility that the US prides itself on fostering. There are some obvious reasons for this. In many cities, wealthy neighborhoods have their own local school systems and community centers with abundant resources to prepare kids for college or skilled jobs. In poor neighborhoods, resources are stretched thin. There are few after-school enrichment programs and little support for kids who need help with learning. We can see the same discrepancies when it comes to hospitals, public parks, and other neighborhood amenities.
Running the numbers
Because cities are built environments controlled by local governments, urban planners often explore whether there might be some way to redesign cities to improve the lives of the people who live in them. If income segregation leads to poor economic outcomes for children growing up in cities, is there some way to encourage mixed neighborhoods? Before we can answer that question, we need to understand what’s causing these rich enclaves in the first place.
That was exactly what Lens and Monkkonen set out to do in their research. They used a data set called the Wharton Residential Land Use Regulation Index (WRLURI for short), released in 2008, which includes information on city regulations from over 2,000 municipalities in the US. Cities get a WRLURI score based on 11 different factors that impact development, including whether there are density restrictions and open space requirements, as well as how many groups have to approve new building projects and whether community meetings are required for rezoning requests. WRLURI scores are used as a broad measure for a city’s regulatory restrictiveness; the higher the score, the more restrictions apply to anyone trying to build things in the city.
Looking at the 95 largest cities in the WRLURI set, Lens and Monkkonen did something that no other city planning researchers had done before. They combined the WRLURI data with a statistical method for measuring income inequality developed by Stanford researcher Sean Reardon in 2004. Reardon’s tool allows researchers to determine how income inequality maps to a geographical region, thus calling into relief which neighborhoods are poor and which are wealthy. As Lens and Monkkonen write, “It is thus possible to analyze whether more stringent regulation of urban development, as measured with the WRLURI, contributes to the segregation of higher- or lower-income households, or both.”
Regulation and isolation
Controlling for variables like population, poverty rate, income inequality, and race (all taken from US Census data), the researchers measured how land uses from the WRLURI data affected income segregation in cities. In other words, they measured how city regulations affected the formation of wealthy and poor enclaves. What they discovered was fascinating. First, they determined that there was a strong correlation between heavily regulated city development and segregated rich neighborhoods. But not all regulations led to this state of affairs.
Three basic categories of regulation are associated with income segregation. As Lens and Monkkonen put it:
We find that particular types of regulation, such as density restrictions, more independent reviews for project approval and zoning changes, and a greater level of involvement by local government and citizenry in the permitting process, are significantly associated with segregation overall and of the affluent.
Essentially, the more cities require independent reviews and community meetings to develop land, the more income-segregated the city becomes. Density restrictions also cause wealthy enclaves, regardless of whether they mandate minimum or maximum density in an area. Even if your city mandates high density housing (or creates special zones for low-density, single-family homes), it won’t necessarily solve the problem of income segregated neighborhoods. Finally, in an interesting twist, it turns out that the more local government and citizens groups control development, the more segregated its wealthiest members become.
This last discovery flies in the face of a lot of city planning wisdom, going back to celebrated neighborhood advocate Jane Jacobs, who believed that local political groups would improve urban life for people of all classes. Now it seems that local pressure groups, sometimes called NIMBYs, can actually have an adverse effect when they focus exclusively on land use regulation. Lens and Monkkonen note that cities where land was controlled by state governments fared much better when it came to fostering mixed neighborhoods.
Mark Hogan, an urban planner in San Francisco who was not involved in the study, called the research “good,” though he noted that it leaves out the question of geography. He told Ars about how zoning regulations have driven prices up in certain San Francisco neighborhoods, effectively creating pockets of ultra-expensive real estate that lead to the segregation of the rich:
Single-family zoning makes up large portions of the western and southern parts of San Francisco and dominates most suburban jurisdictions. Because of a combination of geography and growth regulations to combat sprawl, cities in California cannot sprawl outward like Dallas or Las Vegas. This means nearly all development is crowded into small portions of an already expensive region, making developable land that much more expensive. We are in a situation where there “is no room to build” (outward) yet we have many square miles of land in the center of the our region that are covered with single family homes that historically would have been replaced with denser buildings.
Similar kinds of troubles plague other cities, where land use restrictions artificially inflate real estate values in some neighborhoods, driving out middle-class and lower-income residents.
Can cities change?
Lens and Monkkonen believe that regulations got us here, and it’s possible that changes to the regulations could get us out. In a set of policy recommendations for city planners, they suggest that income segregation might be eased if states were more actively involved in regulating land use. They also suggest that cities relax density restrictions. Cities might also want to create incentives for people to live in mixed neighborhoods. Write Lens and Monkkonen:
We also urge a more extensive implementation of inclusionary housing in the wealthier areas of cities. Such policies have a much greater potential to reduce segregation than the alternative approach of incentivizing affluent households to move into lower-income parts of the city.
Currently, many cities attempt to improve or “re-beautify” lower-income neighborhoods by making them attractive to wealthy people. The idea is that upper income people will move into the neighborhood and bring the benefits of wealth with them. But now, with the rise of isolated, rich neighborhoods, we’re facing the opposite problem. It’s the wealthy neighborhoods that need help to become more diverse. City planners hoping to foster mixed neighborhoods, offering brighter economic futures for kids growing up there, might want to focus on policies that de-segregate wealthy enclaves.
Lens and Monkkonen caution that there is no simple cure-all for the problem of income-segregated neighborhoods. In addition, we need more data on local land use restrictions, especially in urban centers. Still, their work provides a preliminary explanation for why so many cities are developing segregated wealthy neighborhoods. And the researchers provide clear evidence that income segregated neighborhoods are correlated with cities whose land use is subject to stringent regulations and strong local political pressure. Whether cities can act to reverse these trends—or whether they even want to—remains to be seen.
Journal of the American Planning Association, DOI: 10.1080/01944363.2015.1111163