In recent years, the growth of islands in Tigris River increase due to the shortage of incoming water especially at Baghdad City. This led to choking in river cross sections and reduces the river’s ability to pass an extra flood wave along the major cities in addition to problems of deposition at intake of water treatment plants. To overcome this kind of problems, precise engineering study for causes of sediment deposition and rate of deposit are required. One of the powerful tools for such a solution is the application of mathematical models.
Two dimensional mathematical models for water flow and sediment movement are established to predict the amount of deposited sediment and/or scoured from the bed and banks of the river and how river cross-sections characteristics behave due to changes in movable bed (areas of deposition/erosion and type of deposited/eroded materials) during the coming few years . This enables engineers to give practical solutions to reduce the growth of islands in the river. To apply such models field measurement are required. This include river flows, velocity distribution, and suspended sediment load at many cross sections, as well as cross- sections surveying at the area of islands (existed or predicted).