Sehel Island Sehel Island Sehel Island is located in the Nile, about southwest of Aswan in southern Egypt. It is a large island, and is roughly halfway between the city and the upstream Aswan Low Dam. Sehel Island, spanning 3/4 the width of the Nile, is the primary large island below the Nile's First Cataract and the Aswan Low Dam (1902). Following downriver, the next major islands after Sehel are: Saluga, Ambunarti, Elephantine, and then Kitchener's Island. There are a dozen smaller islands scattered around them. The island was known in ancient tiles as "Setet", and there are many archaeological sites, including
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