Comparative analysis and implications of sustainable flood risk management in four front-end countries: the United Kingdom, the Netherlands, the United States, & Japan

Sustainable flood risk management (SFRM) has become popular since the 1980s. Many governmental and nongovernmental organisations have been keen on implementing the SFRM strategies by integrating social, ecological and economic themes into their flood risk management (FRM) practices. However, justifications for SFRM are still embryonic and it is not yet clear whether this concept is influencing the current policies in different countries. This paper reviews the past and present flood management approaches and experiences from flood defence to FRM in four developed countries with the aim of highlighting lessons for developing mega deltas. The paper explored recent strategies such as “Making Space for Water, PPS 25, and NPPF” in the UK; “Room for Rivers” in the Netherlands which was promoted to cope with flooding, integrate FRM with ideas on sustainability, and deliver good FRM practice for next generations. The United States has also established a sound National Flood Insurance Program (NFIP), and Japan has developed an advanced flood warning and evacuation contingency system to prepare for climatic extremes. These case studies showed some good lessons to achieve long term SFRM direction to deliver flood management practices with social-economic and environmental concerns. Most of developing coastal megacities especially in Asia are still heavily reliant on traditional hard-engineering approach, that may not be enough to mitigate substantial risks due to human (exist huge populations, rapid socio-economic growth, subsidence) and natural (climate change) factors. We understand different countries and cities have their own interpretation on SFRM, but recommend policy makers to adopt “mixed options” towards thinking about long term and sustainability that with social, economic and environmental considerations.