Combining mapping with social narratives of flood events to support decision-making for building flood resilience in Sub-Saharan Africa

Abstract

In many African countries, the response to climate change and associated extreme weather events is hampered by a lack of accessible and usable information, such as localized flood maps. Additionally, current methodologies of disaster risk management systems often need to account for factors that can influence human decision-making, such as context-specific drivers of social vulnerability and environmental risks. Such factors are critical for enhancing social resilience to flood impacts as they offer valuable qualitative information to fill in data gaps and plan for an uncertain future. To address these shortcomings, this research presents a mixed-method approach to support decision-making for enhancing flood resilience in Lusaka (Zambia). First, local flood inundation maps were generated with globally available rainfall and GIS datasets. These maps were then interrogated at an interactive and transdisciplinary stakeholder workshop, where historical observations, lived experiences, and different perspectives related to flooding events were discussed. This information was distilled into three different community-based social narratives of flood risk, which were subsequently used to calibrate the computationally generated flood maps with insights from Lusaka´s stakeholders in a flood hazard mapping. A key outcome is that the social narratives formed around the flood maps provide a dynamic entry point for discussing current and future social vulnerability to floods in Lusaka. The results also highlight context-specific challenges and opportunities that would be valuable for stakeholders to consider in pathways to future resilience. Lastly, the value of the research lies in both its outcomes and the process of convening local stakeholders. It provides a sustainable setting for interrogating different types of data, discussing its implications for future planning at the city level, co-producing knowledge together, and building bridges across institutional silos to address the highly interdisciplinary issue of enhancing flood resilience. Given that the resources which the city government and other stakeholders can spend on adaptation and climate resilient development are scarce, future work could build on the findings by evaluating the different measures for enhancing flood resilience which have emerged from the research together with the stakeholders.