GIS-based Walkability Index for Urban Contexts. Application to Luxembourg

Background

For a few years, walkability has been identified as an important component of efficient, accessible and healthy neighbourhoods. Furthermore, many policy interventions promote participation in physical activity particularly through active mobility. Numerous studies demonstrate the impact of neighbourhood environments on the practice of walking. The aim of this study is to assess the neighbourhoods’ walkability of an elderly cohort in Luxembourg. In the framework of a research project about healthy ageing (CURHA project), we propose a new and objective measure of walkability based on a GIS approach at micro level.

Methods

Three main steps are required to compute the proposed index. (1) Delimitation of the potential walking areas. A pedestrian network has been built on the whole Grand-Duchy of Luxembourg. Starting from a Digital Elevation Model, this network integrates topography. Such addition allows to modulate the theoretical speed of the pedestrians according to the slope and delimitate more precisely the potential walking areas based on a fixed access time (15 min from home). (2) Computation of walkability attributes. Within these delimited areas, several attributes of the final indicator can be computed: connectivity, population density, land use mix, proximity and diversity of amenities, and greenness measured by a vegetation index. (3) Construction of the synthetic indicator. A synthetic indicator combining all these attributes is then produced. It takes the form of a standardized ranking indicator from 0 to 100, qualifying the potential of walkability of given addresses (home).