A comparison between the continuous supply and the rotational supply in the distributary canals

Irrigation is generally considered an effective way to increase the agricultureproduction and” thus to provide food for the world growing population. Irrigation cansupply the water needed for crop growth when rainfall is limited or in more humidclimates it can bridge dry periods and reduce risks. Therefore vast investments aremade for the development of new irrigation schemes together with the improvement ofexisting ones.Irrigation in Egypt began about six thousands years ago. The annual floodwhich occurs from August to October led Egyptians to practice both river training andirrigation to improve their existence. Towards this objective perennial irrigation hasbeen practiced in Lower Egypt through a series of control works such as the DeltaBarrage. After the completion of the High Aswan Dam (1970), the entire cultivatedarea in Egypt was placed under’ perennial irrigation. where about 55.5 billion m3 /yearwas made available for irrigation and other purposes. This volume allowed theconversion of all basin into perennial irrigation as well as the irrigation of additionalareas reclaimed from desert and water logged lands.Recently the Ministry of Public Works and Water Resources (MPWWR) hasstarted the Irrigation Improvement Project (lIP) with the main objective to increase theagricultural production of the existing irrigated land in eleven areas in the Nile Deltaand Upper Egypt. One of the measures lIP followed to achieve this objective is toredesign the main and branch canals. In order to obtain an optimal effect of theproposed measures, the Irrigation Improvement Project stresses that the proposedmeasures should be accompanied by a number of modifications in the existing systems.Two of these modifications are changing the irrigation delivery system from arotational supply system to a continuous supply one, and changing from upstream todownstream flow control system.