Cars and Drivers in the New Suburbs: Linking Access to Travel in Neotraditional Planning

Abstract

Various “new suburb” land-use designs have recently been proposed to address a number of social and environmental problems, including the dominance of automobile travel. Transportation benefits are expected from reducing the surface street distance between locations, mixing land uses, “calming” traffic, and promoting walking, bicycling, and transitvia redesigned streets and streetscapes. That auto travel will fall is a largely unchallenged premise of these designs. Yet what little evidence exists is either weak or contrary; this paper presents a simple behavioral argument to explain why. Generally speaking, driving is both discouraged and facilitated in the new suburbs, with the net effect being an empirical matter. In particular, the number of both automobile trips and vehicle-miles traveled can actually rise with an increase in access, such as a move to a more grid-like land-use pattern. Whatever the merits of neotraditional and transit-oriented designs, and there are many, their transportation benefits have been oversold. Each development must be evaluated as a separate case to determine whether its net impact on auto use is positive or negative.