Adaptation tipping points and opportunities for urban flood risk management

Abstract

The effects of climate change are expected to increase the frequency and magnitude of floods, droughts and heat waves. An emerging method termed adaptation tipping point – opportunity (ATP-O) assesses a system's climate-incurred tipping points and uses opportunities arising from urban developments to introduce adaptation strategies while reducing investment costs. The objective of this research was to apply the ATP-O method to the city of Dordrecht in the Netherlands. The results show that the alternative adaptation strategy proposed (an overland drainage system) would be effective in coping with the effects of climate change where the current management strategy (disconnection of impervious surfaces from sewer systems) fails to do so. The ATP-O also proved helpful in identifying opportunities to adapt at lower costs. This research stimulated discussions between stakeholders on performance objectives, policy development, investment strategies, and flood risk management practices. The sensitivity analysis performed to support such discussion revealed that small variations in acceptability thresholds, associated with policy objectives, can have significant impact on ATP occurrence and timing.