Water resources management in modern Egypt water management in Egypt begins with the construction of the Old Aswan Dam in 1902 and barrages on the Nile in the 19th and early 20th century. The Old Aswan Dam partially stored the waters of the Nile to allow the growing of multiple crops per year in the Nile Delta, while the barrages raised the water level of the Nile so that water could be diverted into large irrigation channels running in parallel to the river. The water regime of the river was changed fundamentally in 1970 when the Aswan High Dam was completed, eliminating the annual Nile flood.
Hydropower policy in the United States of 90% efficiency. More importantly, Francis's mathematical and graphical calculation methods advanced turbine design and engineering and allowed confident design of high efficiency turbines to exactly match a site's flow conditions. In the 1870s and deriving from uses in the mining industry, the high efficiency Pelton wheel impulse turbine was developed to use hydropower under very different flow and pressure conditions. Advances in dam design also progressed, with the completion of Old Aswan Dam being considered a milestone of engineering over nature. At the time of its construction, nothing of such scale had ever been attempted: it also became one