Flood risk assessment in Ardabil valley Shirvan aquiferous zone

Many people s lives and property are threatened by annually around the world. Thus, itis necessary to identify areas with flood risk in order to apply systematic managementin urban auriferous zones. First, topographic maps and Si valley Shirvan Riveraquiferous land use was prepared and river basin border was drawn based on thesemaps, then the river divided to 3 sub-basins and these sub-basins divided to 5hydrological unit and these units divided to 4 sub- hydrological units, and floodhydrographs were calculated in return periods of 2, 5, 10, 25, 50, 100, respectively.Within the area of S1-1-1 with a length of 3.5 km in Si valley Shirvan River, geometricinformation of river was obtained. In the next stage, by introduction of flowcharacteristics and river geometric information and each profile coefficient inHEC_RAS software, water level profile in different return periods was calculated andaverage level and depth of flood for risk areas was determined. Finally, using flooddamages functions, damages were calculated and level-damage curve was drawn. Theresults showed that damage increase trend of floods with a return period of more than25 years and average flooding depth greater than 0.52 m is more intense.