Simulation of hydraulics and hydrodynamics of flood in Aghgol wetland using model (HEC-RA)

Author
Zarrin Foroughi
Assistant Professor
10.22034/wmji.2024.2034537.1077
Abstract
Floods every year cause the destruction of the economic and social structure of societies and cause financial and human losses. As a result of climate changes, during recent decades, the country of Iran with its hot, dry and semi-arid climate has been prone to floods. The purpose of this research is to simulate the hydraulics and hydrodynamics of flood in Aghgol wetland using HEC-RAS model. To achieve this goal, two scenarios have been considered. First: Wetland as a water storage area, which enters as two sub-branches into the waterway and Khoruchi of the Wetland and flows out from the north of the Wetland. Second: Wetland as a very wide river. Next, the flood discharge of the basin was simulated using two scenarios with return periods of 2, 10, 25 and 100 years using the HEC-HMS hydrological model. The results showed that, like rivers, the occurrence of floods with a return period of 100 years in the study area will be attributed to flooding of many parts of the lagoon shores, compared to 25-year floods. Also, based on the relations of reservoir calculations, if a flood enters the reservoir which is supposed to be full of water, first some of the volume of the flood is temporarily stored in the reservoir and then it is gradually released. This causes the displacement of the peak flow of the hydrograph and its drop, so that the hydrograph leaving the reservoir has a lower peak and at the same time, its occurrence is postponed.
Keywords
Aghgol lagoon
HEC-RA method
discharge
flood
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