An Assessment of the Integrated Multi-Criteria and New Models Efficiency in Watershed Flood Mapping

Iran is one of the flood-prone areas in the world with inappropriate climatic patterns. In this study, flood risk maps in three scenarios by combining Analytic Hierarchy Process (AHP), Analytical Network Process (ANP) and Fuzzy Analytic Hierarchy Process (FAHP) models with Ordered Weighted Average (OWA), Weighted Linear Combination (WLC) models., Local Weighted Linear Combination (LWLC) and two new models, Weighted Multi-Criteria Analysis (WMCA) and Geo Technique for Order of Preference by Similarity to Ideal Solution (Geo TOPSIS) were prepared from Heraz watershed in northern Iran. The analysis of the results of the AHP model in the first scenario, the ANP model in the second scenario and the FAHP model in the third scenario show that the criteria of precipitation, slope, land use, elevation, drainage density and distance to river are the most important criteria for the occurrence of floods in Haraz basin. Evaluation of flood risk models show that on average, about 70%, 20%, 8%, and 2% of Haraz basin are in medium, low, high, and no flood risk situations, respectively. Geographically, the southeastern and central parts are in high and low flood risk, respectively, and other parts of the basin are in medium risk. In this basin, many forest lands, pastures, agriculture and population centers are in medium and high risk of flooding. Generally, based on the obtained results, WMCA and Geo TOPSIS models along with WLC, LWLC and OWA models are effective methods for flood risk studies and based on the obtained results, Haraz basin needs necessary planning for flood risk management.