Are Portland's Smart Growth Policies Related to Reduced Automobile Dependence?

Abstract

This study evaluates how successful smart growth policies in Portland, best known for its smart growth policies such as the urban growth boundary, extensive public transit service, and transit-oriented developments along the transit corridors, are in achieving one of their policy objectives, a reduction of automobile dependence. Empirical evidence reveals that more diversified land use in neighborhoods, more extensive provision of public transit service, and decreasing accessibility to freeway interchanges were associated with fewer choices of driving alone, while making settlements compact via the urban growth boundary and transit-oriented developments has no clear relationship with reducing the choice to drive alone. Empirical analyses also suggest that provision of public transit service and mixed land use implemented at residential zones (origins) were more effective in reducing automobile dependence than those implemented at places of work (destinations).