Role of pumped hydro storage plants for flood control

Climate change has intensified precipitation patterns and led to more frequent and severe flooding in many locations worldwide. This paper investigates the role of pumped hydro storage (PHS) plants in mitigating floods in Rio Grande do Sul, Brazil. PHS plants can enhance basin water storage, allowing conventional reservoir dam (CRD) to focus on flood control. The paper also suggests the construction of hybrid PHS plants that can be used to store energy during normal operation and be used to pump water during flood events. The results compare the floodwater volume in Guaíba Lake and Patos Lagoon (27 km³) to the 13 km³ displacement capacity of four proposed PHS projects, which could have reduced the total flood level of the Guaiba Lake from 5.33 m to 3.5 m. This would cost 2.7 billion USD, which is similar to the costs of the impact resulted from the flood in May 2024. This infrastructure would significantly reduce the impact of the floods and make the state of Rio Grande do Sul more resilient to climate change in the future. By analyzing the flood water storage capacity required and the storage and pump capacity provided by these solutions, the study aims to prevent future floods and mitigate climate change impacts in the region.