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Aswan Reservoir. Jennifer Sieracki. Location. Aswan High Dam. Begun in 1959 Goals: Provide water for agriculture Prevent release of floodwater to the Mediterranean Prevent flooding and provide water during droughts Produce power. Morphometric Data. Mean depth = 25 m
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Aswan Reservoir Jennifer Sieracki
Aswan High Dam • Begun in 1959 • Goals: • Provide water for agriculture • Prevent release of floodwater to the Mediterranean • Prevent flooding and provide water during droughts • Produce power
Morphometric Data • Mean depth = 25 m • Max depth = 130 m • Surface area = 6,216 km2 • Volume = 157 km3 • Surface elevation = 183 m asl • Length = 496 km • Max Width = 12 km • Shoreline:length = 18:1 Photo credit: J. Sieracki
Inflow • Virtually no rainfall occurs in the region • 84% of floodwaters from the Ethiopian Plateau • 16% from the equatorial lakes (Fahim 1981)
Outflow • Mostly evaporation • Some seepage to the Nubian aquifer Photo credit: J. Sieracki
Benefits of the Aswan Reservoir • Flood and drought control • Increase in agriculture • Increase in electrical power • Increase in Egypt’s national income Photo credit: J. Sieracki
Costs of Aswan Reservoir • Increased seismic activity • Disruption of Mediterranean flow circulation • Increase of water-born diseases • Drowning of archaeological sites • Displacement of Nubian peoples Photo credit: J. Sieracki
Costs of the Aswan Reservoir • Water loss • Salinization and waterlogging • Scouring of downstream sections • Loss of nutrients • Erosion of the Nile Delta • Reduced fish catches in the delta Photo credit: ask.com
Waterlogging and Salinization • Kim, J., and M. Sultan. "Assessment of the Long-term Hydrologic Impacts of Lake Nasser and Related Irrigation Projects in Southwestern Egypt." Journal of Hydrology 262.1-4 (2002): 68-83. Print. • Modeled the possible long-term hydrologic effects of irrigation projects occurring in the Western Desert
Waterlogging and Salinization • Aswan Reservoir has reached max capacity • Water has overflown into Western Desert • Government has two plans for excess water: • Water can be injected back into Nubian Aquifer • Water can be dispersed for agriculture Kim and Sultan 2002
Waterlogging and Salinization • Results (for 2020 and 2050): • Increase in waterlogging • Increase in flooding • Increase in salinization • Change in water table will complicate the distribution of groundwater
Sedimentation • Floodwaters carry silt from the Ethiopian Plateau • Prior to construction of the High Dam: • Nutrient-rich sediments deposited by floodwaters • Silt provided nutrients to the delta estuary • Delta depth was maintained Photo credit: J. Sieracki
Sedimentation • Turbid waters from the Ethiopian Plain no longer reach the dam Latif 1984
Sedimentation Latif 1984
Sedimentation • Problems created by sedimentation: • Lake infilling • Erosion downstream of dam • Deepening of the Nile delta • Loss of nutrients to farm lands • Loss of nutrients to the delta estuary Photo credit: NASA.gov
Lessons for the Future • Developing countries in the tropics are considering similar projects • Must understand problems associated with large dams • Alternatives may include programs in: • Population control • Rural development • Efficient ag production Photo credit: J. Sieracki