Community resources such as local transportation systems influence the spatial distribution of people as well as the relative utility of neighborhoods across metropolitan areas. This research explores the extent to which the population profile of workers living near rail transit differs from those of other workers within the Washington, DC region. To assess demographic changes in rail-accessible neighborhoods over time, this project uses two multi-year American Community Survey (ACS) three-year datasets for comparison, 2006-2008 and 2011-2013. Each dataset is treated as a point estimate spanning three years. The analysis includes the six counties or county equivalents in the Washington, DC region with at least one Metro Rail stop during the study period: Washington, DC; Arlington County, VA; Alexandria city, VA; Fairfax County, VA; Montgomery County, MD; and Prince Georges County, MD. To assess differences across urban and suburban environments, the demographic profiles of rail-accessible neighborhoods in Washington, DC are compared to those of the five counties that surround it.

This project treats ‘access’ as a matter of geographic proximity to a rail stop, which serves as a proxy for one’s ability to access a rail stop by walking. Using Geographic Information System (GIS) software, distance to the nearest rail stop is calculated and assigned to individual workers’ residence blocks. Workers with rail access are defined as those living in a block whose centroid lies within a half-mile of a rail stop. In this paper, the term neighborhood refers to the aggregation of all blocks within that half-mile buffer. Information on rail accessibility is then linked to demographic characteristics of individual workers. Results are presented as distributions of workers along several socio-demographic characteristics such as age, race and Hispanic origin, earnings, household composition, mobility status, and commuting mode.

Findings suggest that, for several population characteristics, rail-accessible neighborhoods differ from those without rail access. For example, in Washington, DC and the surrounding counties, some population subgroups such as young and highly educated workers disproportionately reside in neighborhoods near rail stops. The prevalence of certain groups has also increased at a comparatively high rate in rail-accessible neighborhoods, relative to other neighborhoods. For some population characteristics, the composition of rail-accessible neighborhoods in Washington, DC is notably similar to those of surrounding counties, suggesting that the presence of a rail stop may influence neighborhood characteristics in ways that transcend municipal lines or traditional notions of cities and suburbs.