Aswan extremity of Egypt, the river flows for more than without bar or cataract. The voyage from Aswan to Alexandria usually took 21 to 28 days in favourable weather. Aswan has a hot desert climate (Köppen climate classification "BWh") like the rest of Egypt. Aswan and Luxor have the hottest summer days of any city in Egypt. Aswan is one of the hottest, sunniest and driest cities in the world. Average high temperatures are consistently above during summer (June, July, August and also September) while average low temperatures remain above . Summers are long, prolonged and extremely hot. Average high temperatures
Aswan Dam year. The annual crop consumptive use of water is about . Hence, the overall irrigation efficiency is 38/46 = 0.82 or 82%. This is a relatively-high irrigation efficiency. The field irrigation efficiencies are much less, but the losses are reused downstream. This continuous reuse accounts for the high overall efficiency. The following table shows that the equal distribution of irrigation water over the branch canals taking off from the one main irrigation canal, the Mansuriya Canal near Giza, leaves much to be desired: The salt concentration of the water in the Aswan reservoir is about , a very low salinity