Introducing the Pedestrian Accessibility Tool (PAT): Open source GIS-based walkability analysis

The indices for walkability proposed so far are mostly ad-hoc and refer generally to the closest amenities/public transport stops and the existing network structure. They are ad-hoc as the weights of the attributes are generally arbitrary and do not reflect the independently measured preferences of the users and residents. Furthermore, they do not include design attributes such as the location of crossings and walkway design features, which are very relevant for actual planning decisions. In this paper, we propose a walkability index that can be behaviorally calibrated and has been implemented as a GIS tool and is published as Open Source software. The Pedestrian Accessibility Tool allows evaluating existing and future urban plans with regards to walkability. It calculates Hansen-based accessibility indicators based on customizable specification of generalized walking cost and user-defined weights of destination attractiveness. The basic user work flow of the tool is summarized and three case studies show real-world applications of the tool to support the planning of pedestrian infrastructure in an urban context. By indicating potential areas of improvement that have been reported by pilot users working in an urban planning department, we conclude also giving hints for future research