A.4.2X Contemporary dam building (Aswan dam) Flashcards
Background
Built on the River Nile, south of the city of Aswan in Egypt
2 dams - Aswan Low Dam and Aswan High Dam, completed in 1902 and 1970 respectively
Economic benefits of the Aswan Dam
Recreation and tourism (dam itself is a tourist attraction)
Amount of fishing behind the dam increased, supporting local fishing industry
Building and maintenance of the dam created many jobs and taught local workers new skills
(estimated that the value of the Aswan High Dam to the Egyptian economy is about $500m each year)
Environmental benefits of the Aswan Dam
Water losses: dam provides less than half the amount of water expected
Flood and drought control - dams allow good crops in dry years, e.g. 1972 and 1973 in Egypt (reduces dependency on food imports)
Irrigation - 60% of water from the Aswan Dam is used for irrigation and up to 4000 km of the desert are irrigated
HEP - accounts for 7000m kW hours each year (45% of Egypt’s energy needs)
Economic consequences of the Aswan Dam
Loss of nutrients - $100m worth of artificial fertilisers used annually to replace nutrients (alluvium) trapped behind the dam
Decreased fish catches - sardine yields are down 90% and 3000 jobs in Egyptian fisheries have been lost
Environmental consequences of the Aswan Dam
Salinization - crop yields have been reduced on up to ⅓ of the area irrigated by water from the dam due to salinization
Channel erosion (clear water erosion) beneath the channel; lowering the channel by 25mm over 18 years
Increased sedimentation may put stress on dam, reduce lake depth and prevent nutrients from reaching farmland downstream
Social consequences of the Aswan Dam
Water losses - dam provides less than half the amount of water expected
Displacement of population - up to 100,000 Nubian people have been removed from their ancestral homes
Spread of diseases due to increased stagnant water