Medidas estruturais autoeleváveis na mitigação de riscos hidrológicos: o caso rio doce (Governador Valadares/MG)

Abstract

The municipality of Governador Valadares (MG) has historically suffered from severe floods of the Rio Doce, resulting in significant socioeconomic damage. Currently, hydrological disaster management relies predominantly on non-structural measures, such as early warning systems. Aiming to address the need for physical interventions that preserve urban connectivity and landscape, this study analyzes the technical, hydraulic, and structural feasibility of implementing Self-Closing Flood Barriers (SCFB) along the city's riverfront. The methodology encompassed 1D hydrodynamic modeling using the HEC-RAS software to simulate scenarios and protection elevations for Return Periods (RP) ranging from 2 to 50 years. A preliminary structural stability analysis under hydrostatic loads was also conducted, based on the standards of the Brazilian Association of Technical Standards (ABNT) and guidelines from the U.S. Army Corps of Engineers (USACE). The results demonstrate that 1.60-meter-high barriers provide satisfactory effectiveness for frequent events (2 and 5-year RPs). Under the critical 50-year scenario, the simulation indicated a direct protection potential of 81 hectares, which can be expanded to up to 432 hectares through local elevation adjustments and integration with micro-drainage systems. Preliminary structural analyses demonstrated that the proposed system satisfies the requirements for passive buoyancy activation while maintaining adequate structural capacity under the expected loads. It is concluded that the adoption of SCFB shows preliminary technical feasibility, demonstrating potential for reducing local damage. However, its full effectiveness requires systemic operation with the municipal drainage network, utilizing pumping stations and non-return valves to prevent internal flooding.