From Flood Control to Flood Adaptation
Authors: Mach Katharine J. , Hino Miyuki , Siders A.R. , Koller Steven F. , Kraan Caroline M. , Niemann Jennifer , Sanders Brett F. 
Published: November 2022

Societies throughout the world are experiencing more severe and frequent flooding with consequences for people’s livelihoods, health, safety, and heritage. Much flood risk management to date has aimed to maximize economic benefits, reduce the likelihood of flood disasters, and facilitate recovery where needed. It has assumed a stationary climate and focused on extremes and financial losses. But this paradigm of flood control is increasingly at odds with the full set of challenges and requirements for flood risk management.

Critical challenges motivate a shift from flood control to flood adaptation. First, under climate change, flood risks are intensifying and changing, and new normals are appearing, such as daily high-tide flooding or permanent inundation. Fully controlling flood hazards with one-time interventions is increasingly untenable. Second, floods affect numerous, multidimensional aspects of human and ecological well-being and social justice. Past flood control efforts, and the decision-making processes that produced them, have often failed to address these multidimensional concerns or even had negative side effects. Fundamental adjustments are emerging and will be needed: a guiding paradigm of flexibility rather than control, a system-wide approach with coordinated action across scales, and increased attention to the full range of priorities relevant to successful interventions.

For example, science and research for flood risk adaptation increasingly involve processes supporting usable, inclusive knowledge tailored to decision contexts. Integrative science partnerships such as collaborative flood modeling can incorporate the dynamic physical and social landscapes of flood drivers, impacts, and management. Flexible processes allow updating as flood risks change, and collaborative processes can build intuition, trust, and understanding of risks, including improved awareness of the values and relationships that are threatened and preferred response options. The goal of flood risk management is no longer limited to preventing floods; flood risk management must balance risk tolerances with ecological and social benefits and weigh the trade-offs of management strategies against other societal goals. This “science for society” is inherently political, requiring careful attention to and evaluation of who participates, whose goals are prioritized, and who benefits.

Furthermore, methods of evidence-based decision-making must be able to accommodate deep uncertainties, changing risks and values, and limits to responses. Shifts are already occurring, including dynamic adaptive management practices and improvements to tools such as cost–benefit comparisons. These changes illustrate a larger reframing within flood risk management, away from disaster management focused on extreme isolated events and toward adaptation in response to enduring changes across both extreme and average conditions.

The current challenges of flood risk management create opportunities for integrating lessons from diverse domains of actionable science and public policy and thereby innovating processes of climate adaptation relevant to a range of climate risks.