Definição de regra de operação de reservatórios na região semiárida em situações de escassez hídrica e eutrofização

• Ano de defesa: 2020
• Autor(a) principal: Gomes, Maurício de Gois
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Rio Grande do Norte; Brasil; UFRN; PROGRAMA DE PÓS-GRADUAÇÃO EM ENGENHARIA SANITÁRIA E AMBIENTAL
• Palavras-chave em Português: Operação de reservatórios; Otimização; Qualidade
• Link de acesso: https://repositorio.ufrn.br/handle/123456789/30703

The increase in water deficits and water with improper qualities in the reservoirs may imply conflicts between users, mainly in semi-arid regions because of the reduction in flows during periods of drought. To minimize damage, the strategic operation of reservoirs is an important tool that allows for a satisfactory allocation of available water among users. The Zone-based Guide Curve method was use to optimize the operating rules, the purpose of which is to ration the water uses according to the level of water storage in the reservoir and, thus, preserve a volume of water to meet the demands in a drought future. However, it is also necessary to analyze the quality, since eutrophication in the reservoirs is a factor that limits the uses and availability of water. Thus, this work aims to optimize the operating rule of six reservoirs in the Piancó Piranhas-Açu Basin, located in the semiarid region of Brazil, through simulations of quantity and quality, with the objective of finding satisfactory service to users and reduce water scarcity and eutrophication in reservoirs. In the optimization of the rules, the Multiobjective Genetic Algorithm, NSGA-II, was use to verify in each reservoir what are the ideal limits of zones and its optimized relationship coefficients. In this way, scenarios with different guarantees for meeting priority demands (human supply and animal feed) were simulated and optimized. The results show that optimizing the operating rules considering only quantity does not comply with the quality criteria for supply in most reservoirs. However, considering the quality in the optimization, the supply of priority users in the desired guarantees depends on the concentrations of phosphorus in the water of the reservoirs. It is possible in some scenarios to meet the quality criteria only by rationalizing non-priority demands. However, when concentrations are high, this rationing may be impracticable in addition to causing greater losses through evaporation and pouring. Thereby, it is only possible to comply with the qualitative aspects of the users without causing significant losses if the phosphorus concentrations in the reservoirs are low, therefore, in addition to the increase in the accumulated volumes in the reservoir, it is necessary to carry out actions that mitigate the nutrient inflows in the reservoirs.