Shorter Roads go a Long Way

Abstract

Roads are an important aspect of the efficiency gains that stem from population density: the more people live on a given road network, the less each person must pay for paving, maintenance, and snow clearing. While density is related to the road length per resident, the two variables are not synonymous. Two urban areas may have the same spatial extent and population, yet feature distinct road network morphologies, resulting in different values for road length per resident. Road length per resident measures a major category of costs directly, as a large proportion of many municipal budgets are dedicated to road maintenance. A better understanding of road length per resident can therefore support financially prudent urban development policy. The primary objective of this research is therefore to investigate how road length per resident varies with density between the sub-geographies of cities. Nine cities from across Canada were selected and the road length per resident and net density of their census tracts were calculated. The results present a strong and consistent non-linear association between population density and road length per resident. The present analysis is most valuable for distinguishing between medium-density and low-density suburbs. The results suggest that a shift may be necessary in how urban theorists communicate the costs of low-density growth.