Damietta Branch is one of two River Nile Branches (Damietta andRossetta Branches). It is considered as an important waterway for navigation and irrigation in Egypt with length of 245km. The hydraulic and morphological changes such as scour, deposition,bank erosion, in addition to the encroachment by people on thefloodplain during the last three decades reduced its capacity toconvey high discharges. This research work aims at preparing thisbranch to pass future releases more than the maximum currentrelease. This was performed by comparisons between crosssections under scenarios of increasing discharges from 60 to (80-I 00-120M.m3 / day). Two-dimensional hydrodynamic mathematicalmodel (CCRE) package is used to study the morphological changes in Damietta Branch to predict the effect of high flows on water velocities and geometrical changes in different crosssections. Also the side effects on the navigational channel and overtopping floodplains problems have been investigated.Consequently different solutions were suggested to increase theability of Damietta Branch to convey high discharges.