Green Infrastructure and Flood Resilience in Fatih, Istanbul

Abstract

This thesis focuses on the challenges Istanbul faces due to extensive urbanisation and global warming. The metropole has become vulnerable to climate change, especially to the increasing threat of floods. As a result of urbanisation and poor city planning, the green spaces have decreased considerably in Istanbul, which reduced stormwater retention considerably. This is concerning, as green infrastructure provide ecosystem services that can serve as flood control. The thesis describes the context of Istanbul’s flood governance, including international, national and metropolitan flood policies and Istanbul’s flood resilience actor-network. In Istanbul’s flood risk management plans, the role that green infrastructure can play in flood control has been neglected. To meet this gap, this study aims to analyse how green infrastructure could enhance Istanbul’s flood resilience. Fatih is one of the oldest districts in Istanbul and is taken as a case study due to its high vulnerability to flash floods. The study presents a case study on Fatih with a spatial approach to monitor flood resilience and ecosystem services through green infrastructures that can foster resilience. A Geographic Information System in combination with a multi-criteria evaluation is used as a tool to identify priority areas for green infrastructure investments. Finally, the effect of three green infrastructure investments is analysed. The research finds that the indicators proposed by Li et al. (2016) are appropriate to use to analyse the priority areas for green infrastructure investment. These indicators reflect a system approach as they include technical, environmental as well as social variables. This is important for the city of Istanbul, as they provide a holistic framework with these indicators. Furthermore, using the flood map provided by ISKI, the flood sensitive areas in Fatih have been identified, and especially the infrastructures surrounding the main boulevard are subject to flooding. Molla Gürani resulted to be the neighbourhood being most flood vulnerable, and therefore the main priority is for green infrastructure development. For this neighbourhood, increased green infrastructure is modelled. The results show a significant reduction in flood vulnerability, which concludes the part green infrastructure have in flood control. The thesis concludes that there is no one-size-fits-all response to enhance flood resilience. Especially since flood resilience is not only based on flood mitigation but rather coping and transforming from floods. Green area investments prove useful to enhance resilience, as these investments provide benefits that can transform the resilience of urban flood management into a more adaptive state due to the nature of the ecosystem services. This research proposes a few recommendations for decision-makers in Istanbul to take into consideration.