Aswan Dam links the reservoir to the Toshka Depression. The reservoir, named Lake Nasser, is long and at its widest, with a surface area of . It holds of water. Due to the absence of appreciable rainfall, Egypt's agriculture depends entirely on irrigation. With irrigation, two crops per year can be produced, except for sugar cane which has a growing period of almost one year. The high dam at Aswan releases, on average, water per year, of which some are diverted into the irrigation canals. In the Nile valley and delta, almost benefit from these waters producing on average 1.8 crops per
Aswan average relative humidity of only 26%, with a maximum mean of 42% during winter and a minimum mean of 16% during summer. The weather of Aswan is extremely clear, bright and sunny year-round, in all seasons, with a low seasonal variation, with almost 4,000 hours of annual sunshine, very close to the maximum theoretical sunshine duration. Aswan is one of the sunniest places on Earth. The highest record temperature was on July 4, 1918, and the lowest record temperature was on January 6, 1989. In 1999, South Valley University was inaugurated and it has three branches; Aswan, Qena and Hurghada.