It’s Not Just Risk—It’s Responsibility: Changing Drivers of Home Flood Protection

Private household adaptation is a critical yet underutilised element of flood resilience. Property-level measures might reduce up to 80\% of damage if adopted in a timely manner. However, socio-behavioural factors serve as constraints to adaptation. Among them, a lack of risk awareness is considered a primary barrier. Empirical research typically relies on a single snapshot of data, implicitly assuming these factors are stable over time. Using two nationally representative survey waves from the Netherlands (2020 and 2023), we examine how factors of household intentions to implement six structural home-flood protection measures change. Counterintuitively, despite a major flood in 2021, by 2023, we find lower adaptation intentions (an 11.6 percentage point decline), lower flood worry, and reduced self-efficacy. This coincided with a marked shift in perceived responsibility for flood risk toward the government (12 percentage point increase), while the actual uptake of private adaptation measures remained low (2-5\%). Regression analysis reveals a reordering of behavioural drivers: in 2020, prior flood experience, self-efficacy, and flood worry were the most prominent predictors, though perception of responsibility was also consistently significant. By 2023, perception of responsibility emerges as the strongest and most consistent predictor of intention to act (odds ratio 2.4), while the importance of flood experience and worry declines. These results suggest that household drivers for adaptation are volatile, relying not only on a household's experience and capacity to act but also on the understanding of shared responsibility between citizens and the state. "Empowering" households only with information about potential flood risk, while rationally sound, may not result in an intention to protect homes. Climate adaptation policy design that embraces private action must therefore include: clear responsibility framing, support for skills development and the efficacy of measures, targeted financial incentives, and adaptability to account for evolving public attitudes, even over short timeframes.