Urban flash flood vulnerability: spatial assessment and adaptation - a case study in Istanbul, Turkey

The Ayamama River basin in Istanbul is a densely populated urban area that is frequently impacted by flash floods causing damage to people and infrastructure. The IPCC expects that under climate change conditions, more intense precipitation will occur, leading to a higher risk of flash floods. Approaches to assess vulnerability focus on particular hazards without relating to climate change; usually emphasizing either physical or social vulnerability. However, enabling governance systems to deal with risks due to climate change requires participation of local inhabitants and inclusion of local knowledge for planning effective climate change adaptation measures. This paper presents a framework for a spatial assessment of urban vulnerability to flash floods under climate change conditions. Qualitative interviews were conducted to capture local knowledge of citizens in the Ayamama area about flood events and climate change. Spatial multi criteria evaluation was applied to calculate vulnerability indices.