Adopt a resilience lens in flood risk management

An interdisciplinary group of experts from Deltares, other research institutes and universities argues in a new opinion paper that extra elements must be added to flood risk management in order to make better decisions and develop strategies which enhance resilience and equity. Their paper was recently published in Nature Communications Earth & Environment.

Chris Zevenbergen, who chairs the IHE Delft Institute for Water Education research group on flood resilience and one of the authors of the opinion paper, said: “adapting the flood risk approach would benefit vulnerable groups. Particularly in low-income countries poverty is a major driver of vulnerability to floods”. The elements will help to better align development priorities with flood risk management. This is more needed than ever before”.

Karin de Bruijn, flood resilience expert at Deltares and lead author of the paper, said the paper’s key messages help focus flood risk management on the people that suffer most: “We should look beyond measures which provide protection in the most efficient way, and also consider what may happen if protection systems are overwhelmed, or how we could limit impacts in less-protected areas by enhancing recovery capacity. To better understand the full story of how floods turn into disasters -next to conventional risk analysis- we should study historic events and develop storylines for possible future events,” she said.

Adapting the flood risk approach would benefit vulnerable groups. Particularly in low-income countries poverty is a major driver of vulnerability to floods

Chris Zevenbergen - Head of IHE Delft's research group on flood resilience

Bramka Jafino, economist at the Global Facility for Disaster Reduction and Recovery, the World Bank, said: “The ever-increasing complexity of flood risk demands a new way of approaching it. The standard probabilistic-based risk approaches and cost-benefit analysis, though still very relevant, are not sufficient anymore. This perspective piece calls for approaching flood risk management from a resilience lens – and proposes four concrete elements to do so.”

Focus on welfare instead of on asset losses
While most flood risk studies take cost-benefit analyses at the heart of the selection of adaptation measures, this study calls for more just and equitable assessment of measures. The importance of a dollar is not equal for everyone and losing a home is disastrous irrespective of its monetary value.
Including recovery capacity
Differences in flood impacts across societal groups often link to differences in their ability to recover from flood impacts. To recover, physical damage must be repaired and income generating options must be restored. “The framework better enables us to understand the full potential of damages and incorporates communities’ ability to respond and recover. This is essential to consider the wide range of losses and positions us well to manage flooding and reduce the negative impacts on society,” said Sally Priest, head of the Flood Hazard Research Centre at Middlesex University.
Preparing for extreme beyond design events
Extreme events can easily lead to disasters when flood protection systems are overwhelmed, and people and authorities are caught by surprise. Bruno Merz, head of the Hydrology section at the GFZ German Research Centre for Geosciences, Potsdam states said: “We need to better prevent disastrous surprises by exploring the consequences of events beyond the current design standards. Such scenarios help to better prepare affected people and disaster management and reduce calamitous impacts.”
Assessing distributional impacts of floods and of measures
The authors plea for more comprehensive, better-informed and transparent decision-making which allows for openly discussing inherent conflicts between advantaged and disadvantaged people in flood risk management strategies as well as opportunities including investment decisions. Neelke Doorn, Professor of ethics in water engineering, and Tina Comes, Professor in decision theory & ICT for resilience, both affiliated to the Faculty Technology, Policy & Management, Delft University of Technology, noted that climate and flood risks are not distributed equally, and that crises amplify existing inequalities. Measures that put societal welfare first will benefit the most vulnerable people, they argued.

The paper argues that adopting a resilience lens to flood risk will contribute to a more just world. Jeroen Aerts, Deltares expert and head of the department ‘Water and Climate Risk’ at Vrije Universiteit Amsterdam, said: “We now can and therefore should address distributional impacts to avoid increasing inequity, shorten recovery time and make communities more resilient for future floods.”