Managing residual flood risk: Lessons learned from experiences in Taiwan

Flood risk has dramatically increased over the decades and is complicated by climate change. Nevertheless, the residual risk of flooding remains scarcely addressed in practice and theory. This paper is to document the lessons learned from managing residual risk in Taiwan. Through a semi-structured interview process, fourteen stakeholders from the flood management in academia, government, and local communities shared their perspectives on residual risk covering various aspects, including flood risk mapping, social representations, and some management strategies. Land use regulation and community-based disaster prevention were highlighted as preparedness measures and recognized for their effectiveness to mitigate flood residual risk. However, there is still an insufficient consideration of flood maps as public communication tools rather than mere decision-informing documents. Besides, all the interviewed stakeholders agreed that marginal flood risk awareness limits the recognition and discussion of residual risk as a problem of its own. Misconceptions and the lack of communication between stakeholders were identified as the main barriers too. Interviewees pointed out that citizens are unaware of risks mainly either due to their inexperience or over-trust in the safety of flood protection structures. Overall, this work may inform residual flood risk management for Taiwan and elsewhere enduring similar extreme floods.