Water resources management in modern Egypt about 3.5 BCM/year of municipal wastewater was being discharged into the Nile and the sea in 2002, out of which only 1.6 BCM/year (about 45%) were treated. Industrial effluents contribute to about 1.3 BCM/yr of wastewater being discharged to surface waters, only some of which is being treated. Hydropower. An important use of water in Egypt is for the production of hydropower. This use is non-consumptive and is thus available for other uses further downstream. Hydropower plants exist at the Aswan High Dam (2100 MW), the old Aswan Dam (270 MW)and power plants at the Esna (90 MW) and Naga
Aswan Low Dam 1907–1912 and between 1929–1933, and generation of electricity was added. The first phase was supervised by Sir Benjamin Baker, though much of the detailed work was undertaken by Murdoch MacDonald. With its final raising (designed and supervised by MacDonald's firm, Sir M MacDonald & Partners), the dam is in length, with a crest level above the original riverbed; the dam provides the main route for traffic between the city and the airport. With the construction of the High Dam upstream, the Old Dam's ability to pass the flood's sediments was lost, as was the serviceability provided by the locks. The