In central Vietnam, small and medium-sized coastal towns are particularly characterised by a rapid urbanisation trend. The concomitants include extensive surface sealing, the expansion of settlements into flood-prone areas, and a decline in infiltration and retention areas, so that heavy rainfalls lead to enormous surface runoff. Additionally, the narrow and flat settlement area between the inland mountains and the coast only allows very short reaction times to heavy rainfall, which is exacerbated by degraded land and deforestation. Moreover, climate change is expected to lead to stronger and more frequent extreme weather events, such as typhoons with resulting floods in central Vietnam. Such storms cause considerable infrastructural, agricultural, health and economic damage. Due to changing settlement patterns, housing and lifestyles, local vulnerabilities and civil adaptation practices need to be rethought and integrated into planning.

FloodAdaptVN applied a transdisciplinary approach combining hydrological and hydraulic modeling, socio-economic vulnerability assessments, and Earth observation-based risk analyses. Scenario-based modeling was used to anticipate future flood risks, incorporating »Representative Concentration Pathways« (RCP) and »Shared Socioeconomic Pathways« (SSP). Participatory co-design and visioning exercises engaged local stakeholders in identifying adaptation priorities and measures. The project integrated these data and methods into »FRAME«, a WebGIS platform that supports spatial visualization, cost-benefit analyses, and dynamic risk assessments for adaptive planning and decision-making.

In the R&D phase of the FloodAdaptVN project, interdisciplinary research and stakeholder collaboration resulted in a broad portfolio of innovative solutions to reduce flood risks in Huế and the wider region. The project developed high-resolution flood hazard maps and future scenario-based risk assessments that integrate socio-economic and climate change factors. A central outcome is the development of the FRAME system, a WebGIS-based decision-support tool that consolidates risk data, scenario analyses, and adaptation options. FRAME enables local authorities and planners to visualize risk patterns, prioritize adaptation measures, and integrate ecosystem-based solutions into spatial planning. Additional innovations include data-driven cost-benefit analyses of different adaptation measures and the design of bundles of interventions that combine structural, social, and nature-based options. This comprehensive approach ensures that future urban and regional planning is risk-informed and climate-resilient.