Flood zoning of Noran River with a return period of 100 years using HEC-RAS hydrodynamic model

Rivers are considered as the main source of water supply for humans and other creatures, and sometimes this source of life causes irreparable damage and destruction. Predicting the hydraulic behavior of rivers against possible floods is very important to reduce the damage caused to urban and rural areas, facilities under construction, farms and other existing uses around the river. Flooding is a natural phenomenon and there is a risk of its occurrence around rivers. It is a global issue, especially in urban and rural areas. The purpose of this research is flood zoning of Noran River with a return period of 100 years using HEC-RAS hydrodynamic model. The main data required for this research include: 1:2000 topographic maps of Nuranchai River, hydrometric data and boundary conditions of the river, which were obtained from the regional water organization of Ardabil province. Also, SMADA software was used to calculate the flood return period. The results of the research showed that flood zoning with a return period of 100 years was determined that the effect of the flood with an area of 304 hectares and the width of the flood zone is about 445 meters. It will be dangerous and should be given great importance in future planning to flood risks with a return period of 100 years.