Urban planning method for fostering social sustainability: Can bottom-up and top-down meet?

Abstract

The main topic of the present study is the discrepancy occurring when traditional top-down approaches to urban planning are applied to settlements that have been formed in spontaneous, informal bottom-up manner. The problem we are investigating is whether derived properties of informal settlement morphogenesis, when integrated into the planning process, can enrich the pool of possible solutions traditionally achieved with top-down planning. The proposed approach consists of two distinct, yet closely related steps. In the first step, spatial patterns of bottom-up morphogenesis were observed based on available data (census data, data from utility companies, and orthophoto images). Based on these patterns' formation, a mathematical model of morphogenesis was derived. The proposed modelling paradigm is a particular variant of field-based stochastic cellular automata. The model was validated by means of numerical simulations; by comparing simulated morphogenesis with the actual development of the observed settlement (selected case study Veternička rampa, Republic of Serbia). Validated patterns were used as inputs to the second step, where the Huff model was applied in a top-down planning process. The obtained results demonstrate that this novel approach can expand the scope of possible spatial solutions for local centers in informal settlements beyond one's foreseen by top-down planning, thus contributing to integrating an informal settlement into a wider urban environment, fostering their social sustainability.