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Abstract Actions to reduce flood risk often appear to run counter to other societal goals, and resolving these conflicts is important as flood adaptations increasingly transform settlements and societies. Here, we evaluate the tensions between flood risk reduction and other priorities in the context of voluntary buyouts of flood-prone properties in the United States—a controversial flood response to restore land to open space, but with trade-offs. We apply a nation-wide systematic review (133 literature references, 1983–2023) to assess goals stated for buyouts and combine it with a comprehensive media analysis (281 media articles, 1993–2023) to compare those goals to the experiences and results perceived by buyout implementers, residents, and other practitioner groups. Across the systematic-review literature, flood risk reduction dominates goals expressed for buyouts (62.6% of documented goals), and local government predominates in this goal setting (61.7% of documented goals). However, involved and affected actors—especially residents—perceive outcomes beyond flood risk reduction, most notably in the experiences of buyout implementation itself (35.5% of documented resident perceptions) and in results impacting social and economic priorities (49.5%). Despite the difficulties of buyouts, the systematic-review literature largely reflects positive perceived outcomes (79.4% of outcome sentiments, weighing each buyout location equally), but nonprofit organizations and residents perceive largely negative outcomes. Media coverage related to buyouts is more negative than positive but with improved sentiments through time. Our findings point to the importance of designing, implementing, and evaluating flood adaptations not just as flood control measures given their consequences for other societal objectives. The uneven documentation on buyouts also implies opportunities to learn from contexts where buyouts have been integrated into everyday life with little fanfare, through mechanisms either novel or perhaps routine, yielding insights into making ambitious climate adaptations a common, more ordinary, and increasingly imperative occurrence. 

Abstract Avoiding floodplain development is critical for limiting flood damage, yet there is little empirical evidence of how local governments effectively avoid floodplain development. We conduct a mixed-methods study to explain how local floodplain management influences floodplain development in New Jersey, a state with high development pressure and flood risk. We find that 85% of towns developed relatively little in the floodplain from 2001 to 2019, and they achieved this with commonplace land use management tools and modest levels of local government capacity. One hundred twenty-six New Jersey towns put none of their new housing in the floodplain 2001–2019. Our findings run counter to common reports of rampant floodplain development requiring legal innovation and capacity-building campaigns and suggest alternative approaches for promoting floodplain avoidance. We find multiple paths to floodplain avoidance, weak support for previously identified drivers, and strong evidence that the keys to avoidance include having a few high-quality tools that are well-implemented, requiring consistency, coordination, and commitment of local officials. The multiple paths and importance of maximum, rather than average, quality might explain the mixed evidence in prior research connecting floodplain management actions and development outcomes. A lack of attention to towns that limit floodplain development impedes our ability to learn from and disseminate their successes. Contrary to our expectations, we show that floodplain avoidance can be and is achieved through routine municipal practices. Our findings underscore the importance of sustained commitment to development management as a core tool for limiting flood risk. 

Abstract Extreme flooding events are becoming more frequent and costly, and impacts have been concentrated in cities where exposure and vulnerability are both heightened. To manage risks, governments, the private sector, and households now rely on flood hazard data from national‐scale models that lack accuracy in urban areas due to unresolved drainage processes and infrastructure. Here we assess the uncertainties of First Street Foundation (FSF) flood hazard data, available across the U.S., using a new model (PRIMo‐Drain) that resolves drainage infrastructure and fine resolution drainage dynamics. Using the case of Los Angeles, California, we find that FSF and PRIMo‐Drain estimates of population and property value exposed to 1%‐ and 5%‐annual‐chance hazards diverge at finer scales of governance, for example, by 4‐ to 18‐fold at the municipal scale. FSF and PRIMo‐Drain data often predict opposite patterns of exposure inequality across social groups (e.g., Black, White, Disadvantaged). Further, at the county scale, we compute a Model Agreement Index of only 24%—a ∼1 in 4 chance of models agreeing upon which properties are at risk. Collectively, these differences point to limited capacity of FSF data to confidently assess which municipalities, social groups, and individual properties are at risk of flooding within urban areas. These results caution that national‐scale model data at present may misinform urban flood risk strategies and lead to maladaptation, underscoring the importance of refined and validated urban models.