Investigation of the impact of extreme flood flow on the Shatt Al-Arab River and Marsh system

The Shatt Al-Arab River is one of the main sources of surface water in the Basrah Governorate, which is important for domestic, industrial, and agricultural purposes. It is a tidal river affected by the tidal and ebb of the Arabian Gulf. This study focused on the effect of extreme flood flow in the Shatt Al-Arab River that leads to riverbank overflow, floodplain inundation, and rise in water level in the adjacent Al-Hammar Marsh. The flood inundation map is produced using the 2D HEC-RAS model (Version 6.4.1). The results offer a way to predict the flood extent and show the impact of the extreme flood flow, it showed that Basrah city is the most dangerous location exposed to flood on the right bank of the Shatt Al Arab River. Suitable management is needed to address the risk. This study highlighted the importance of flood control and operation of the Shatt Al-Arab River in the wet seasons and the need for an emergency plan so that the impact of the potential losses during the peak flood can be mitigated and at the same time, the benefit is optimized through water storage in the marsh system.