University of California Transportation Center

This paper deals with the process of change in urban systems, specifically the changes in the relationships between urban transportation and food retail distribution activities. The dynamic properties of food retailing and transportation systems are identified by tracing location patterns of food stores in Seattle, Washington. Increases in travel demand due to food shopping trips are estimated based on changes in spatial arrangement of food retail activities over the past 50 years. The study suggests that improved transportation services permitted spatial competition of food stores by increasing store size and scope, which in turn influenced the changes in travel patterns for food shopping. Larger stores mean more traffic on principal arterials since higher level stores require higher level services. As stores became larger and larger, store locations grew increasingly farther apart, requiring consumers to travel longer distances for food shopping. As competition heightened, the stores were more uniformly distributed.