Hydrologic-Hydraulic Modeling

Local-scale food hazard projections in historically vulnerable communities

Flooding poses one of the most devastating natural hazards, with climate change projected to increase both frequency and magnitude of flood events, disproportionately affecting vulnerable communities like Jackson, Mississippi. Previous flood hazard studies have been limited by coarse spatial resolution inadequate for community-scale assessments, reliance on historical conditions that underestimate climate-driven changes, and failure to incorporate critical infrastructure that significantly alters flow patterns. This study integrates climate projections from NEX-GDDP-CMIP6 models under SSP245 and SSP585 scenarios integrated with a physically based hydrologic model and two-dimensional hydrodynamic model to project localized 100-year flood hazards. Results reveal flood extent will increase 2-7% from the current baseline, population exposure will nearly double by 2080 under high emissions, and critically, a wastewater treatment lagoon faces flood depths exceeding 3 meters, threatening contamination of downstream potable water supplies. This scalable and transferable framework provides actionable insights for policymakers to prioritize flood resilience investments, enhance critical infrastructure protection, and develop equitable floodplain management strategies in vulnerable urban communities across the globe.

Hydrodynamics of cascading dam failure: Edenville-Sanford sequential breach

Aging dams across the United States face increasing risk from intensifying floods, as demonstrated by the catastrophic Edenville-Sanford cascading dam failures in Michigan in 2020. This study used a calibrated two-dimensional hydrodynamic model to reconstruct the breach sequence and evaluate how different spillway gate operations influenced breach initiation and downstream flooding. Four scenarios were simulated ranging from fully closed gates to fully open gates, with the model validated against satellite imagery and field flood marks showing good spatial agreement. Results revealed that closed and partially open gates produced water levels exceeding breach-initiating thresholds at both dams, while fully open gates maintained safe water levels below critical thresholds and prevented breach, significantly reducing flood extent and maximum depths. These findings provide essential guidance for developing proactive spillway operation protocols and emergency action planning at aging dams with limited spillway capacity.