By Chris Hess (University of Washington, Seattle)
Public infrastructure has always shaped patterns of metropolitan growth and residential segregation. Street-car lines, followed by highways, created important corridors from cities out into the so-called “Crabgrass Frontier” (Jackson 1985). New access to undeveloped suburban areas combined with government-insured mortgages with low down-payments generated vast opportunities for housing construction. However, through much of the 20th century “redlining”, discriminatory housing covenants, and exclusionary zoning maintained a system of residential stratification preventing racial and ethnic minorities from moving outward to burgeoning suburbs. Consequently, many urban neighborhoods became racially-segregated, faced disinvestment due to housing policy favoring lending to suburban contexts, and experienced increasing “mismatch” from suburban employment growth.
Trends of gentrification in many cities have shifted the geographic location of metropolitan growth “back-to-the-city”, and public investments into transportation still play a role in this process. Light-rail projects are a popular investment among urban leaders because of their capacity to improve transit service while also creating opportunities for remaking neighborhoods as walkable, mixed-use spaces. While these goals are worthwhile, light-rail and other transit projects can also make neighborhoods with high racial and ethnic minority representation targets for population and housing growth. As a result, the process of building new rail transit with transit-oriented development (TOD) can create gentrification pressures for existing residents. “Priced out” households may need to expand their housing searches to new destinations, though they may be less desirable locations with fewer neighborhood resources.
My article in UAR uses the recent Link Light Rail project from Seattle, Washington and two nearby suburbs to study how neighborhoods’ ethnic and racial compositions changed in the period following the light-rail project’s construction and opening. Throughout the analyses of this study, I find substantially different trends in neighborhood population composition based on geographic location inside or outside of Seattle. Neighborhoods near Link in Seattle had increases in their non-Hispanic White population amidst relative decreases in the share of Asian and Pacific Islander persons. In contrast, two suburbs that Link traverses changed from nearly all-White compositions before Link to majority-minority by the post-inauguration observation corresponding to the 2010- 2014 period. Taken together, these different patterns of neighborhood change correspond to an evolving shape of residential segregation due to gentrification in urban neighborhoods.
The following set of maps illustrate the absolute change in neighborhood populations from Link’s planning in the 1990s to the period following the project’s inauguration (i.e. 2010-2014). This type of visualization uses data from the 1990 Census and 2010-2014 American Community Survey to summarize the composition of each neighborhood’s population (note, the points are randomly placed within each cell because census data is aggregated). Seattle’s boundaries are highlighted with a bold grey line, while Link’s route and stops are indicated with a black line and boxes. Each dot represents 200 persons of an ethnic or racial group. The purple plus symbols correspond to non-Hispanic White persons, the blue rectangles to non-Hispanic Black persons, the green triangles to Asian and Pacific Islander persons, and the yellow hollow squares to Hispanic persons.
In 1990 (left), the study area shows a distinct pattern of segregation between neighborhoods. At this point in time, the Link was being planned so the line and stations are included for demonstration. The predominantly-Black Central District is to the right of Westlake station, the northern terminus for the segment of Link studied here. After the light-rail line cuts eastward (i.e. right in the map), the route stretches through several racially-integrated neighborhoods where Link stations (e.g. Beacon Hill, Columbia City) would later be constructed. Non-Hispanic White persons make up the clear majority of neighborhood residents in the surrounding neighborhoods in Seattle and in the suburbs to the south (e.g. near SeaTac Airport Station).
The map on the right shows the composition for the 2010-2014 post-inauguration period, and several changes are noticeable. Towards the northern end of the Link route, the station areas are almost hard to make out because of the substantial population growth in Seattle’s downtown neighborhoods. The Central District neighborhoods east of Westlake Station became mostly-White in their composition. From Beacon Hill to Columbia City, many places have smaller Asian/Pacific Islander and Black populations amidst increased numbers of White persons. In contrast, the suburban light-rail neighborhoods experienced substantial decreases in their White populations amidst rapid growth in their Asian/Pacific Islander, Hispanic and Black populations.
The other analyses of the study then try to disentangle how much of the observed change in neighborhood composition related specifically to the Link project. Seattle has experienced considerable gentrification in general, so the research design approximates the average trends for what might have happened if not for the light-rail project using the average trends for a set of control neighborhoods. I model the relative size of neighborhoods’ Asian/Pacific Islander, Black, Hispanic and White populations during the planning, construction and inauguration periods for Link and define the neighborhoods that saw the greatest planning for redevelopment as the “treatment group”. I adjust for starting differences in housing and population composition to rule out these alternative explanations for Link-related neighborhood change.
These models indicate that there was substantial average neighborhood change net of the Link project (that is, declining Black populations throughout Seattle and growing numbers of Hispanic persons). On average, though, Seattle light-rail neighborhoods had declining shares of non-Hispanic Asian/Pacific Islander persons, amidst growing shares of non-Hispanic Whites. There were no Link-related trends in the suburbs of Tukwila and SeaTac because all neighborhoods in these places experienced the same trends of substantial population change.
Overall, the results of this study demonstrate that patterns of residential segregation, while alleviated some relative to 1990, are nonetheless evolving amidst gentrification in Seattle. They now reflect a metropolitan form where rising affluence in urban neighborhoods creates a counter-flow of less-advantaged households to older, inner-ring suburbs. Regional planning literature describes the area around the suburban stages as having “weak market demand” and “limited access to opportunity” . Infrastructure and related revitalization should include more robust protections for housing affordability to make projects more equitable and preserve neighborhood social contexts.
Jackson, Kenneth T. Crabgrass frontier: The suburbanization of the United States. Oxford University Press, 1987.
Chris Hess is a PhD student in sociology at the University of Washington, Seattle. He is also graduate trainee of the Center for Studies in Demography and Ecology (CSDE). His work centers on residential segregation, neighborhood change and household residential mobility.