Impact of County-Level Built Environment and Regional Accessibility on Walking: A Washington, DC-Baltimore Case Study

Existing research on built environment's impact on nonmotorized travel behavior has focused on neighborhood-level factors. However, because people live and work at a regional scaleusing transit and cars to access jobs and other destinationsit can be hypothesized that a region's built environment can also be influential in nonmotorized travel behavior. This study examines the role of county-level built environment and regional accessibility in walking by developing mixed-effects models applied to household data from the Washington, DC and Baltimore metropolitan areas. The results indicate that in addition to neighborhood-level built environment, county-level built environment and regional accessibility can affect walking travel behavior by residents. The findings suggest that land-use policies to promote walking will not be fully effective if only considered at the neighborhood level. More effective land-use policies are those that consider the overall physical form of urban areas, including the composition of population and employment, the extent of street network connectivity, and regional accessibility across an entire metropolitan area.