Channel narrowing to mitigate saltwater intrusion in the Shatt Al-Arab River, Iraq

The salinity of the Shatt Al-Arab River in Iraq has been on the rise. This study looks at a potential engineering solution to the problem of upstream saltwater intrusion. The solution consists of re-narrowing the river channel, which has been adjusted over the years to accommodate sediment build-up. This study consists of salinity analyses for the years 1977–2024, field measurements of electrical conductivity (EC), flow velocity and discharge and hydraulic modeling using HEC-RAS, as well as analytical models of tidal attenuation and salinity. Model simulations suggest that, under the assumed scenarios, channel narrowing may reduce tidal energy, alter flow velocities, shorten the predicted salt intrusion length from approximately 62 km to about 42 km under low-flow conditions and lower EC values in the northern reach. These results indicate that channel narrowing could be considered as part of integrated water resources management. However, further field validation is required to confirm the model predictions.