Building Flood Resilience: A Grand Challenge for U.S. Water Policy

Earlier this month, Hurricane Beryl caused extreme flooding across the country, from Texas to Vermont, in many cases impacting communities that were still recovering from catastrophic flooding in 2023. Flooding has become the most expensive and frequent disaster in the United States. Since 2000, flooding events occur almost daily, and the cost of inland flooding alone in 2023 was nearly $200 billion. Flooding also has major implications for human health and well-being through degrading housing conditions, loss of mobility and economic opportunity, and impacted ecosystems and environmental conditions. Many of the households and businesses most vulnerable to flood risk have the fewest resources available to prepare for and respond to a flood.

Addressing flood risks and building flood resilience represents a grand challenge for U.S. water policy due to the scope of its impacts, along with the complex set of policies, regulation, science, and financing programs that underpin flood risk and require transformation for effective and equitable solutions.

The reasons for the expanding risk and impact of flooding are varied. First, due to climate change, storms are increasing in severity and frequency, causing flooding on the coasts, along rivers, and in cities. Second, much of the infrastructure in place to mitigate flooding is undersized, outdated, and out of repair. Stormwater systems, coastal flood barriers, and inland dams and levees have often been designed to outdated performance standards, including to historical climate conditions that no longer hold, and have been poorly maintained over time. Much of the natural infrastructure that historically served as a barrier to flooding, like vegetated areas next to streams, has been impaired or destroyed.

Third, housing policies, land use planning, and economic development processes have created incentives and opportunities for increased investment in areas at high risk of coastal or inland flooding, while at the same time increasing the amount of impervious surface area, exacerbating flood risk. The governance and financing of elements critical to flood risk and mitigation—land use, insurance, stormwater permitting, hazard mitigation planning, infrastructure financing, environmental protection, housing policy—tend to be disjointed and fragmented, with little coordination between them.

Tackling this challenge therefore requires transformations in many systems fundamental to how and where people live, work, and build. New insights into the critical needs and possible opportunities for transforming these systems are emerging and can support better policy and decisionmaking, identify new solutions, and inform the evaluation of alternatives and trade-offs. Specifically, we highlight three ways innovative, collaborative efforts can help build flood resilience in the United States.

1. Update the information environment: There is a lack of accurate and targeted information (e.g., climate change projections, floodplain maps, land use requirements, and data on previous flood exposure) readily available for communities and decisionmakers. Improving their availability, accessibility, and usability is an important step toward building flood resilience. Decision-ready information is needed to support planning on various timescales, from immediate flood response to long-term flood resilience. For example, the Harris County Flood Control District in Texas has made significant strides, integrating real-time data from rain gauges and bayou water levels to provide accurate flood risk information to residents and policymakers. This initiative has helped the city better prepare for and respond to flooding events.
2. Envision new futures with communities: Addressing flood risk and building flood resilience requires transformative approaches to designing infrastructure and investing in communities. Decisionmakers must partner with communities to develop shared visions of flood resilience using new tools and methods. For example, FloodGen uses AI to generate photorealistic images of potential flood scenarios, raising awareness and enhancing community preparedness. Community engagement involves not just consultation but active partnership to co-create solutions that reflect their unique needs and aspirations. The Milwaukee Metropolitan Sewerage District partners with communities, government agencies, and non-government agencies to reduce the risk of flooding through infrastructure improvements. Innovative and equitable approaches to community collaboration can help decisionmakers pursue resilient futures.
3. Strengthen the governance and financing of flood resilience: Building flood resilience requires finding and leveraging points of intersection and collaboration among existing governing structures and financing mechanisms. For example, the state of Vermont has developed a comprehensive approach to flood resilience through its “Flood Ready Vermont” initiative. This program integrates land use planning, hazard mitigation, and infrastructure investment to create a coordinated and effective response to flood risks. Building understanding of how and when current systems (e.g., insurance, financing, regulation, permitting, watershed management) impede resilience-building can help identify the most effective and feasible alternatives.

Building flood resilience can save lives, reduce costs, and help address persistent inequities. The examples above highlight the innovative approaches already being taken across the United States. Learning from, and scaling up, effective and justice-centered approaches is a needed next step.