Local-scale flood hazard projections in historically vulnerable communities (Datasets and Models)

AbstractFlood events are increasing in both frequency and severity due to climate variability, global warming, and anthropogenicdisturbances, posing growing risks to human settlements, transportation networks, and critical infrastructure. We employ an integrated framework that couples climate projections with physically-based semi-distributed hydrologic and hydrodynamic models to project fluvial flood hazard. This study focuses on the City of Jackson in Mississippi, United States whichis highly vulnerable to frequent floods due to socio-economic challenges, poor housing, and health disparities. Using multiple climate models and two Shared Socioeconomic Pathways (SSP245 and SSP585), we assess localized 100-year floodhazard projections. Results indicate a significant increase in flood hazards under future scenarios. Currently, about 24,700residents live within flood-prone areas, a number projected to nearly double by the late 21st century. Downtown Jacksonis expected to experience disproportionately greater flood impacts. Single-story, single-family residential buildings withoutbasements are among the most exposed structures. A particular concern is a wastewater treatment lagoon located within a high flood hazard area on the right bank, where projected flood depths exceed 3 m, posing a serious contamination riskto the downstream potable water treatment facility. This study provides valuable insights for policymakers and planners to prioritize investments in flood resilience, enhance critical infrastructure protection, and develop equitable floodplainmanagement strategies. The proposed approach is scalable and adaptable for other flood-prone urban communities.