Development of flood mitigation strategies toward sustainable development

Decreasing flood damages in a basin and achieving sustainable development reveal the necessity of integrated management of flood. Integrated flood management requires the co-implementation of both structural and non-structural flood mitigation strategies. Watershed management, building dams and levees, and increasing channel capacity are considered among structural measures. While, flood forecasting, developing flood early warning systems, and establishing reservoir operation rules can fall into the non-structural measures group. The main goal of this study is to reveal the importance of co-implementation of structural and non-structural measures for managing the flood in the whole system. Structural measures are divided here into two main groups (1) dams and (2) watershed management, and non-structural measures focus more on reoperation of the system of reservoirs. The system dynamics (SD) approach has been used to model the integration of a series of structural and non-structural flood control measures for the Karkheh Basin, Iran. The performance of the developed model is evaluated based on historical floods, including the recent 2019 flooding event in this basin, and the performance of flood mitigation strategies is evaluated facing these flood events. Results indicate that both structural and non-structural solutions should be considered in flood management portfolios simultaneously, and none solely can be the silver bullet. The magnitude of a 200-year flood can be reduced from 7956 to 3021 m(3)/s, if integrated structural and non-structural strategies would be considered in Karkheh Basin. This study identifies the key role of structural and non-structural measures for integrated flood management in Karkheh Basin, which and provides effective information for appropriate and timely operation and decision making in the future.