Analysing the interaction between transport demand reduction and urban redesign based on a 15-minute city concept

This study investigates the feasibility of urban design that is based on the ideals of citizens on what travel times, modes and urban densities should be, through the development of a multi- objective optimisation model. It is found that walkable 20-minute neighbourhoods are viable in the South African context, although this comes at a price. The study provides evidence of the trade-off between the number of buildings and services provided, housing density and the average travel time required to access essential goods and services. Given the limited economic resources in South Africa, the economic feasibility of an oversupply of services to reduce average travel distances renders the acceptability of solutions that will provide maximal satisfaction to residents questionable. The Pareto set of solutions generated can be subjected to contextualised posterior analysis to identify the best fit solution for a specific application, finding the compromise between the economic, environmental and social objectives of planners and decision makers.