A Computational Application of Urban Network Analysis on Walkability in Design Decision Making

Using the TOD neighborhoods of Waipahu on Oahu, which is comprised of two localities referred to as the West Loch Station and the Waipahu Transit Center Station, as a case study, the present work aims at investigating to what extend different aspects of the built environment may affect walkability in urban neighborhoods. By means of Geographic Information Systems (GIS), spatial, network, and statistical analyses were performed on a selected set of components of the urban built environment. Residential density, commercial density, mixed landuse, and street connectivity were measured to determine how the following 8 urban aspects —mixed-land use, small blocks, interesting architecture, building density (commercial and residential), residents’ physical activity, the impact of density and mixed-land use— affect transport mode or urban mobility. To better understand the walkability patterns around these TOD neighborhoods, we applied the method to Portland, which is known for being a walkable city. As Jeff Speck claims, for a place to be walkable, it is all a question of proper balance of uses, so it is important to look for what is missing or under-represented in an urban setting, whether it is office, retail, dining, entertainment, housing, school, recreation, worship, or parking (Speck 2013). The proposed graph-analysis framework can be used by professionals to improve planning and designing decisions to make cities more attractive and sustainable. However, it is not intended to replace the existing ways of evaluating walkability, but instead, it is to be seen as an additional layer of information to be introduced at an early stage of any project