'The Nile Control Works', early 1920s.
© Science Museum / Science & Society Picture Library
A map of Egypt and Sudan, showing existing and proposed projects to regulate the flow of the waters of the Nile, including the Aswan Dam and the barrages at Zifta, Esna and Asiut. Since the late 19th century, a number of schemes have been implemented to try to control the flow of the Nile in order to improve irrigation, increase the area of agricultural land, reduce the severity of flooding, and develop hydro-electric power. The schemes had mixed succes, and in 1970 the Aswan High Dam was built to resolve the shortcomings of some of the earlier barrages and dams. Although it has been largely succesful, the Aswan High Dam has had the adverse side effect of stopping nutrient rich sediments from being carried downstream.