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
Tsiazompaniry Dam Tsiazompaniry Dam The Tsiazompaniry Dam is a buttress dam on the Varahina-South River, a tributary of the Ikopa River, near Tsiazompaniry in the Analamanga Region of Madagascar. The dam was constructed by a French firm in 1956. It creates Lake Tsiazompaniry, the largest reservoir in the country, which has a surface area of and a storage volume of . A second buttress dam, northwest of the main dam helps withhold the reservoir. Water released from the dam supplies a regulated flow to hydroelectric power station at the Antelomita Dam downstream. Efforts to install a 5.25 MW power station at the