Estimation of potential flash flood risk in a basin using morphometric parameters: A case study of Akcay Basin

In this study, the Akcay basin located in Western Black Sea Region was divided into sub basins and the geometrical parameters of those sub basins, the drainage network and the stream orders specified by the Strahler method were determined by using ArcGIS 10.1.Thus, the morphometric parameters of each sub basin were computed.Then, in order to be able to evaluate the sub basins in terms of flood potential, a prioritization method in the literature was adapted and with the usage of the morphometric parameters the sub basins were graded according to their flood potentials. According to the sub basin prioritization carried out, it was determined that the reservoir of the Yunuslar HEPP located in the Akcay basin enclosed the sub basin which had a high flood potential and constituted approximately half of the total drainage area of the basin. Furthermore, it was suggested that construction of a check dam in the sub basin which has the largest drainage area and a river bridge located at its outlet point would reduce the potential effect of the flash flood for both the river bridge and the whole basin. The flash flood potential of all sub basins was also investigated by using lesser number of morphometric parameters according to a graphical method in the literature and the flash flood potential of all sub basins was found to be moderate according to this method.