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 the summer solstice, a vertical staff cast no shadow. They noted that the sun's disc was reflected in a well at noon. This statement is only approximately correct; at the summer solstice, the shadow was only of the staff, and so could scarcely be discerned, and the northern limb of the Sun's disc would be nearly vertical. However, Eratosthenes used this information together with measurements of the shadow length on the solstice at Alexandria to perform the first known calculation of the circumference of the Earth. The Nile is nearly wide above Aswan. From this frontier town to the northern