Flood hazard zonation using multi-criteria analysis and GIS (case study: Izeh Township)

Numerous floods in different parts of the country have always led to a lot of damage in various fields; thus, preparing a comprehensive plan of flood control seems essential. Residential and urban development in the riversides and the bed of the floodplain regardless of hydrological and hydraulic conditions of the river causes increased flood risk. Therefore, flood management and identification of vulnerable zones is essential to reduce annual flood damage and minimize the damage and control it in the urban and rural environment. The aim of this study is to fine-mapping of flood risk in Izeh city.
To achieve this target, 12 indicators namely aquifers, climate, vegetation, elevation, geology, and distance from waterway network, geologic formations, land use, evaporation, isorain, and isothermal were used. The relative weight of criteria was obtained using AHP method and the target layers have been overlapped using geographic information system.
Findings: The final map of flood zonation showed that about 43 percent of the city is at very high risk zone; 16.14% is in the high risk zone, 12.46% is in medium risk zone, 10.19% is in the low risk zone and 8.3 percent is in very low risk zone in terms of flood prevention. The map shows that about 60% of the city areas are in the very high and high risk zones of flooding.
according to damage assessment map, the greatest damage among the Izeh City areas is related to eastern and western Susan, and the villages of the south river trail. In fact, areas that are located in mountainous location are under threat of flooding because all of these areas are between the mountains or the intersection of the valley and gorge. In general, it can be said the flood hazard zoning maps help to non-structural flood management and allow planners to select the safe areas in terms of flood prone for the purpose of development