Assessing the Dam-Break Flood Hazards of the Largest Dams in the state of Pernambuco, Brazil

Código

I-EBHE0167

Autores

Maria de Andrade Rocha Alencar Castro, Marcus Nóbrega Gomes Júnior, Luis Miguel Castillo Rápalo, Eduardo Mário Mendiondo

Tema

WG 1.03: Urban Water - Urbanization phenomenon & adequate water management

Resumo

Dams, and the reservoirs behind them, are one of the most widespread forms of storage construction in the world. However, they are potential sources of disasters when necessary measures are not taken to maintain them. According to the National Dam Safety Information System (SNISB), the degree of risk of a dam depends on the Risk Category (CRI) and the Associated Potential Damage (DPA), these classifications consider variables such as technical characteristics of the dam, state of conservation and potential for human losses. The Resolution No. 91 of 2012 of the National Water Agency, regulates that dams classified as high CRI and DPA require the preparation of Action and Emergency Plans (PAEs), a document that must cover the flood map and extent, which is usually derived from hydrodynamic modeling. These are necessary to obtain an estimation of the flood wave propagation and channel-floodplain dynamics, however, the quality of the input data has a strong influence on obtaining these results. Therefore, the evaluation of the influence of these parameters is essential, since they can constitute a source of uncertainness. The objective of this work is to evaluate the impact that input data and model configuration have on the results obtained by hydrodynamic modeling. To this end, the failure of the 10 largest dams, classified as high risk and potential damage in the State of Pernambuco, will be simulated in models such as HEC-RAS, HydroHP-1D and HydroPol-2D. This work presents a framework for a simplified approach to assessing the impacts of floods arising from dam failures and can contribute to Action and Emergency Plans, as we deal with dams with high potential damage.