Flood Control Using a Combination of Delayed Dam and Coastal Dike (Case study: Kan river basin)

In the present study, a combination of delayed dams in the upstream basin with the coastal dike in the downstream of residential area of the Kan river was studied, so that for this combination, the cost of constructing the structures is minimized and the reduction of flood peak is maximized. For this purpose, multi-criteria decision method and TOPSIS method were used and the best option was determined. This research showed that for the best combination, if 3 delayed dams with coastal river dike are constructed, the peak of output flood reduce to 31.5%. In addition, the diffusion and elongation of the output hydrograph in the superior state were significant and the time of concentration of flood increase.