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 Dam exchange rate in 1970 of $2.30 per E£1): £140 million from agricultural production, £100 million from hydroelectric generation, £10 million from flood protection, and £5 million from improved navigation. At the time of its construction, total cost, including unspecified "subsidiary projects" and the extension of electric power lines, amounted to £450 million. Not taking into account the negative environmental and social effects of the dam, its costs are thus estimated to have been recovered within only two years. One observer notes: "The impacts of the Aswan High Dam (...) have been overwhelmingly positive. Although the Dam has contributed to some