AN EVALUATION OF THE EFFECT OF THE CONSTRUCTION OF WALKING SPACES ON THEIR NEIGHBORHOOD ENVIRONMENTS USING WALKABILITY INDEX: WITH A FOCUS ON THE REUSE OF DISCONTINUED RAILROADS

摘要

Across the world, several discontinued railroads have been reused through the construction of walking spaces. One example is the High Line, a former railroad viaduct converted into a public walking space in New York City, USA. Such spaces are expected to have a good effect on the neighborhood walking environments. However, the method to quantitatively evaluate the effects of such constructions in terms of walking activity has not been fully developed. This study focuses on "Walkability," which is an indicator for evaluating urban living environments where walking activities are promoted. More specifically, "Walkability Index" (Wl), calculated using certain geographical environmental factors, indicates the degree of residents" walking activity. WI enables us to evaluate complex neighborhood environments by calculating the sum of these multiple factors and by comparing values across timeframes or areas. This study aims to analyze and quantitatively evaluate using WI the effects of constructions of walking spaces on their neighborhood environments. The authors conducted spatiotemporal analysis for the neighborhood environment around the High Line and two other comparative cases in Japan, using the geographical information system (G1S). Through the results, the authors demonstrate that: (1) WI in polygon meshes around the middle section of the High Line had improved after the construction. (2) Compared with other public spaces in New York City, WI around the High Line had relatively improved after the construction. Accordingly, the authors conclude that the construction of the High Line had effects of improving the neighborhood walkability and that the neighborhood environment displayed more characteristics that promoted walking activity as compared to other areas in the City.