Hydrological-Hydrodynamic Modeling of Climate Change-Induced Urban Floods Using Design Rainfall with HydroPol2D: A Case Study in São Carlos, Brazil
Published in RBRH, 2026
Abstract: In climate change scenarios, the frequency and intensity of urban flooding events are expected to increase, leading to more severe impacts on cities. Thus, the coupling of spatially distributed hydrological and hydrodynamic models is essential for simulating flood propagation and identifying susceptible areas within urban catchments. This study aims to assess the influence of extreme precipitation events on flood dynamics in the urban catchment of São Carlos, under both current climatic conditions and future projections derived from climate change scenarios (ETA-MIROC5 for RCP scenarios 4.5 and 8.5—4.5 W/m² and 8.5 W/m²). To analyze how precipitation influences flood propagation and the extent of inundated areas, the fully distributed two-dimensional hydrological-hydrodynamic model HydroPol2D was applied. This model solves the equations for the conservation of momentum, mass, and pollutant transport on a Cartesian grid. This methodology was applied to selected urban catchments in São Carlos (SP), Brazil—a city recognized as a technology hub that suffers from episodes of intense rainfall and, consequently, flooding. These events continue to trigger recurring crises, resulting in both material and non-material losses. The results revealed that, on average, inundated areas increased by 65% compared to current conditions. Furthermore, for events with a 100-year return period, maximum flood depths increased by up to 2.5 meters in specific locations within the catchment area.
Recommended citation: Sousa, M.R.D., Mendiondo, E.M. and Gomes Júnior, M.N., 2026. Modelagem hidrológica-hidrodinâmica de inundações urbanas induzidas por mudanças climáticas com chuvas de projeto usando o HydroPol2D: estudo de caso em São Carlos, Brasil. RBRH, 31, p.e02.
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