Growth in urban area retail sales occurs in suburban but not in downtown locations, according to most recent surveys. This study, developing from NCHRP research into travel characteristics associated with shopping centers, airports, and manufacturing plants, was aimed at at assessing the role played by highways, if any, in this development. The characteristics of market areas within a fixed travel time from a hypothetical cbd and shopping center were compared. Then it was assumed that urban area-wide highway improvements take place, bringing about an increase in average travel speeds and thus enlarging the market areas accessible within the same travel time as before. A test case, using socioeconomic and network data from the Niagara frontier transportation study, was used to demonstrate the conclusions of these hypothetical cases. For values of travel time coincident with a typical market area boundary for the shopping center, it was found that gross family incomes totaled more in the shopping center market area than in the area within the same travel time from downtown. When highway improvements affecting the whole urban area are introduced, the relative advantage of the shopping center is enhanced. Implications with respect to downtown redevelopment activities are briefly discussed. The condition described is likely to have its greatest impact where the traditional community retail center is not truly central, but somewhat removed from the present and future centroids of urban population and income. /author/.
Abstract