Participatory approach to data collection for GIS for flood risk management in informal settlements of Cape Town

Abstract

A by-product of the apartheid era in South Africa is that most informal settlements in Cape Town are situated on marginal and often poorly drained land. Consequently, most of these settlements are prone to flooding after prolonged rainfall. Informal settlements are often characterised by high population growth and poor infrastructure. Current flood risk management techniques implemented by the authorities of the Cape Town City Council (CTCC) are ideal for formally planned settlements but are not designed to support informal settlements. In fact, owing to a lack of information about the levels of flood risk within the individual settlements, the CTCC has often either been uninvolved or it has implemented inappropriate remedies within such settlements. Various authors purport that the inadequate flow of information between all stakeholders has hampered development of sustainable flood risk management strategies. Using a case study of a flood prone informal settlement in Cape Town, this paper demonstrates a methodology for the collection and integration of community based information into a Geographic Information System (GIS) that can be used by the CTCC for risk assessment. In addition, this paper shows how data collected from communities can demonstrate micro levels of vulnerability and guide risk management strategies. This work contributes to the body of Participatory GIS (PGIS). The overall contribution of this work lies in demonstrating a practical participatory approach to data collection for GIS that is used for development of sustainable flood risk management strategies in informal settlements.