Flood Control by Weir Design Using HEC-RAS Model: The Case of Al-Musandaq Escape

Abstract

Proper flood control plays an important part in designing hydraulic structures and environmental safety measures. However, in Iraq, a clear understanding either of the estimation or management of the magnitude of flooding is yet to reach a higher level. This has resulted in grave and frequent damage to much property and life in Maysan town. Therefore, this study was focused on the Flood Hazard contro; in the River Tigris at the downstream of Al-Kut Barrage to the Al-Musandaq Escape, by adopting the HEC RAS model. Here, information related to the hydrological and topographical Digital Elevation Model (DEM) data were used as the input data. The hydrological data enabled the estimation of the flood depth of the river, for April 2019. All the geometric data were prepared by the HEC-RAS model. The unsteady-state model simulation was performed employing the input data. In this study, the best method for flood control and management is to design a weir having an optimal level, the optimum level that does not permit the passage of a flow that exceeds 700 m3/s to the city of Maysan during the flood season and a flow that is not below 250 m3/s during the dry season, is 9.406 m.