Assessment of torrential flood susceptibility: Case study - Ukrina River Basin (B&H)

Torrential floods are the most frequent natural catastrophic events in the Republic of Srpska (B&H). The main objective of this study is susceptibility assessment to torrential floods in Ukrina River Basin using Index Based Method (IBM) and Flash Flood Potential Method (FFPI), which operates entirely in a GIS environment. The definition and identification of influencing factors for torrential floods was the first step in the process of developing the Torrential Flood Susceptibility Model (TFSM). According to the results of these models, 54.00% and 40.86% of the Ukrina Basin area is in the categories of strong and very strong susceptibility to torrential floods. The second task was to identify the torrential basins and create the Register and the Cadastre of Torrential Basins in the Ukrina River Basin. After detailed field survey and analyses, 154 torrential basins have been identified, occupying 551.37 km2 of the Ukrina Basin. According to the validation indicators of the Torrential Flood Susceptibility Model, 138 torrential basins are in the category of strong and very strong susceptibility according to Index Based Method, while 112 torrential basins are in the same category of susceptibility according to Flash Flood Potential Index Method, which are very good results of the validation. This paper presents the significant step towards better understanding of the phenomenon of torrential floods in the Republic of Srpska (B&H). The data presented in this paper are also significant to practical issues such as integral water management projects, spatial planning, sustainable land planning and protection of soil, forest ecosystems and environmental protection, sediment management, agriculture and other human activities.