Modelling and simulating urban expansion in Africa

ESRC New Investigator Award

This ESRC-funded project addresses an important gap in quantitative urban research by developing an openly accessible model for predicting patterns of spatial expansion in African cities. According to UN estimates, Africa’s cities will house almost one billion additional people over the next 30 years (UN, 2018). Much of this increase will occur in informal settlements yet the most popular urban expansion models are not well-suited to contexts of ‘informal urbanisation’. Generating better predictions of patterns of urban expansion in Africa is crucial for planners and policy makers seeking to effectively allocate resources and improve urban living conditions. This project pursues four main objectives.

(1) Develop an urban expansion model for African cities that can be parameterised to account for the diverse socioeconomic and regulatory conditions that underpin processes of urban development on the continent;
(2) Validate the model in a range of primate and secondary cities across the continent;
(3) Make predictions regarding the likely locations and legal status of new residential developments in a large sample of African cities; and
(4) Disseminate the model to academics and practitioners through open access publications, an interactive website for the model, and training local planners and African researchers on how to use and modify the model to suit their needs.

Achieving these objectives will not only help address the persistent ‘Western bias’ in urban modelling, but also provide openly accessible decision support tool for improving current and future decision making about planning and resource allocation in Africa. The project will build on my previous research, which developed TI-City, an urban growth model that combines agent-based modelling and a geophysical simulation approach to predict urban growth in Accra (Ghana), accounting for the institutional and socioeconomic factors that shape the decisions of households and developers. The project will generalise TI-City model to account for the dynamics and processes of urban expansion in different African contexts. The generalised model will be validated and used to predict future urban expansion in Lagos and Onitsha in Nigeria; Kumasi and Tamale in Ghana; Nairobi and Nakuru in Kenya; and Pretoria and Bloemfontein in South Africa.