Simulação hipotética de rompimento da barragem de Tabatinga usando como metodologia o HEC- RAS

Abstract

The construction of dams generally promotes socioeconomic development in the regions where they are built. However, they also pose the danger of potential structural failure, which, when combined with disorderly urbanization in downstream risk areas, can cause significant and long-lasting socio-environmental impacts. Therefore, in this study, a hydrodynamic simulation of the flood wave caused by a hypothetical breach of the Tabatinga dam, located in the municipality of Macaíba-RN, was carried out with the objective of extracting the resulting flood stain to assess the possible impacts on the region downstream of the dam, using maps representing the extent, speed, depth, and arrival time of the flood wave. This was done in order to facilitate the development of possible contingency and risk mitigation plans. In conducting this study, QGIS software was used to delimit a Digital Elevation Model (DEM), which was later exported to HEC-RAS, where the boundary conditions were defined and the simulation area was constructed, enabling the flood wave to be generated. The results indicated a flood spot with a maximum length of 25 km and an approximate area of 32.22 km², affecting five urbanized regions. Among the impacted areas, the center of the city of Macaíba, located approximately 10 km from the dam, stands out, which was hit by the flood wave in about 1 hour and 38 minutes, with an estimated speed of up to 3 m/s. The affected area totaled 221.15 hectare, with depths of up to 13 meters at certain points.