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River Nile. Content:. Profile of River Nile Branches of River Nile Flooding in River Nile Measures dealing with flooding Pros & Cons of building the Aswan Dam. Profile. Location:.
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Content: • Profile of River Nile • Branches of River Nile • Flooding in River Nile • Measures dealing with flooding • Pros & Cons of building the Aswan Dam
Length: River Nile is the longest river in the world. (From White Nile Source to Mouth) 6695km (4184 miles). • Sources: The White Nile: Lake Victoria, Uganda. The Blue Nile: Lake Tana, Ethiopia. • Countries: 9 countries. The White Nile : Uganda, Sudan, and Egypt. The Blue Nile : Ethiopia, Zaire, Kenya, Tanzanian, Rwanda, and Burundi all have tributaries, which flow into the Nile or into lake Victoria Nyanes. • Cities: Cairo, Gondokoro, Khartoum, Aswan, Thebes/Luxor, Karnak, and the town of Alexandria lies near the Rozeta branch.
Source Elevation:1,134 m (3,721 ft) • Watershed Area:3,400,000 km² (1,312,740 mi²) • Flow Rate: The Nile River's average discharge is about 300 million cubic meters per day.
Flow Direction: The River Nile flow from south to north. The river flows down hill, from the high mountains in the middle of Africa to the Nile delta (point where Nile enters the Mediterranean Sea).
White Nile • The farthest headstream of the Nile is the Ruvyironza River in Burundi, which is an upper branch of the Kagera River. • The Kagera flows for 690 km (429 miles) before reaching Lake Victoria. • Leaving Lake Victoria, the river is known as the Victoria Nile. It flows further for approximately 500 km (300 miles), through Lake Kyoga, until it reaches Lake Albert. • After leaving Lake Albert, the river is known as the Albert Nile. It then flows into Sudan, where it becomes known as the Bahr al Jebel. • At the confluence of the Bahr al Jebel with the Bahr el Ghazal, itself 720 km (445 miles) long, the river becomes known as the Bahr al Abyad, or the White Nile, from the clay suspended in its waters. From there, the river flows to Khartoum. White Nile River, Sudan (from NASA)
Blue Nile • The Blue Nile (or Bahr al Azraq to Sudanese; Abbai to Ethiopians) springs from Lake Tana in the Ethiopian Highlands. • The Blue Nile flows about 1,400 km (850 miles) to Khartoum, where the Blue Nile and White Nile join to form "the Nile.“ • Most of the water carried by the Nile (about 83%) originates from Ethiopia, but this runoff only happens in summer, when the great rains fall on the Ethiopian Plateau; the rest of the year the great rivers draining Ethiopia to the Nile (Sobat, Blue Nile, and Atbara) flow weakly or are dry. Blue Nile Falls
The Nile • After the Blue and White Niles merge, the only remaining major tributary is the Atbara River, which originates in Ethiopia north of Lake Tana, and is approximately 800 km (500 miles) long. It joins the Nile approximately 300 km (200 miles) past Khartoum. The Nile is also unusual in that its last tributary (the Atbara) joins it approximately halfway to the sea. From that point north, the Nile diminishes because of evaporation. • The Nile then reaches the man-made Lake Nasser, impounded behind the Aswan High Dam 270 km (170 miles) into Egypt from the Sudanese border. Since 1998 some of Lake Nasser's waters have spilt westward to form the Toshka Lakes. The Blue White Nile Confluence
From Lake Nasser the main channel flows north through Egypt and into the Mediterranean Sea; a side channel, the Bahr Yussef, splits from the main channel downriver from the city of Asyut, and empties into the Fayum. Where the Nile meets the Mediterranean, the Nile Delta, is the eponym of all river deltas worldwide. Enrichment from Nile sediments carried eastward by currents nurture the fishing industries of the Eastern Mediterranean, or used to before the Aswan High Dam was built. • The Nile in Sudan is distinctive for two reasons: 1) it flows over 6 groups of cataracts, from the first at Aswan to the sixth at Sabaloka (just north of Khartoum); and 2) it reverses course for much of its course, flowing back to the SW before returning to flow north again to the sea. This is the "Great Bend of the Nile". The Great Bend of the Nile in Sudan, looking north across the Sahara Desert towards Lake Nasser and Egypt. ( from the International Space Station, courtesy of NASA. )
Flooding along the White Nile • Heavy rains in Sudan flooded the White Nile. The river was swollen from rains. • The area between the White Nile and the Blue Nile to the east is dotted with pools of standing water as well. • In these images, water is blue, vegetation is bright green, naturally bare soil and low vegetation are tan and drab green, and clouds are light blue and white. • The flooding has displaced 13,000 people, leaving more than 3,000 homeless, and destroying crops.
Flooding of the Nile Delta • The mean sea level at the Nile Delta has been rising 1.2 1.3 mm/yr. Continued coastal subsidence, which increasing sea level, ranges between 15 mm/yr .Therefore, the sum of the local and global estimates may lead to relative sea level rise at the Nile Delta coast which could be of 1 m by the year 2100. • In fact, a considerable part of the delta coast lies below 1m elevation and some parts are below sea level. For these reasons, the implications of rising sea level on coastal erosion and flooding may lead to greater hazards to the coastal zone of the Nile Delta. • Severe beach erosion is predominating along the coast and will continue and increase in future especially at the Rosetta and Damietta headlands. • Coastal flooding is expected to increase due to rising sea level and storm surges in future. Surges and winter storms would also penetrate farther inland leaving a coastal area of at least 7000 km2 more vulnerable. The Nile Delta
The Aswan Dam & The Lake Nasser • Aswan is a city on the first cataract of the Nile in Egypt. Two dams straddle the river at this point: the newer Aswan High Dam, and the older Aswan Dam or Aswan Low Dam. • The aim of this water project was to prevent the rivers flooding, generate electricity and provide water for agriculture.
The Aswan High Dam Basic Statistics • Location: Aswan, Egypt • Completion Date: 1970 • Cost: $1 billion • Dimensions:980 m wide at the base, 40 m wide at the crest and 111 m tall. • Reservoir Capacity: 5.97 trillion cubic feet • Discharge:At maximum, 11,000 m³ of water can pass through the dam every second. • Type: Embankment • Purpose: Flood control, hydroelectric power, irrigation • Reservoir: Lake Nasser • Materials: rock, clay
Name: Lake Nasser • Length: 480 km • Width: 16 km • surface area : 6,000 km² • Capacity: 150 to 165 km³. The Lake Nasser
Uses of Lake Nasser : • Water is pumped from Lake Nasser to people's homes for drinking, washing and cooking. • Farmers use water from Lake Nasser to irrigate (water) their crops. • Holiday Companies such as Thomas Cook offer cruises of Lake Nasser. The cruises take in all the sights along the banks of the reservoir. • Lake Nasser is not used for water sports because it is used mainly for drinking water. There are no facilities available by the banks of LakeNasser for watersports. A cruise boat in Lake Nasser
Pros • Relief flooding: It protects high floods as well as from low floods. The effects of dangerous floods in 1964 and 1973 were mitigated. • Power generation: it produced around half of Egypt's entire electricity production and allowed for the connection of most Egyptian villages to electricity for the first time.
Mitigated Drought:The effects of dangerous threatening droughts in 1972–73 and 1983–84 were mitigated • Economic benefited: A new fishing industry has been created around Lake Nasser, though it is struggling due to its distance from any significant markets. • Fertile soil: The silt makes the Nile region fertile. • Navigation: Makes navigation of the Nile possible year round.
Recreations: It created Lake Nasser which provides recreation. • Irrigation farming: It guarantees the availability of irrigation water at any period for agricultural production. • Agricultural expansion: It expands the agricultural land in million of acres. Three stages of irrigation around the Nile. Picture for a history schoolbook.On display in the dutch national museum of antiquity in Leiden.
Cons • Chemical pollution: The need to use artificial fertilizers supplied by international corporations is controversial too, causing chemical pollution which the traditional river silt did not. • Silting: silting of the reservoir, which will eventually render Lake Nasser useless for water storage volume. • Erosion: There is some erosion of farmland down-river. Erosion of coastline barriers, due to lack of new sediments from floods, will eventually cause loss of the brackish water lake fishery that is currently the largest source of fish for Egypt.
Stalinization: Indifferent irrigation control has also caused some farmland to be damaged by waterlogging and increased salinity, a problem complicated by the reduced flow of the river, which allows salt water further into the delta. • Spread of disease: The dam has been implicated in a rise in cases of Schistosomiasis (bilharzia), due to the thick plant life that has grown up in Lake Nasser, which hosts the snails who carry the disease. • Affecting marine ecosystem: Mediterranean fish stocks are also impacted by the dam. The eastern basin of the Mediterranean is low in fertility, and traditionally the marine ecosystem depended on the rich flow of phosphate and silicates from the Nile outflow.
Resettlement: To build the dam, Nubia has been flooded and 90, 000 Egyptian peasants had to move. • Destruction of archaeological sites: During its construction in the 1960s, the Aswan Dam held back greater amounts of water each year. As the water rose, many important archaeological sites were flooded, such as these sphinxes lining the avenue of the Temple at Wadi es-Sebua. In 1964, the sphinxes and temple were rescued and put on higher ground.
Source of information • http://www.imbc.gr/imbc/biblio_serv/medcst/X0120_097.html • http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11161 • http://en.wikipedia.org/wiki/Nile • http://www.mbarron.net/Nile/ • http://users.rowan.edu/~sassie01/dams.ppt • http://www.kented.org.uk/ngfl/subjects/geography/rivers/River%20Articles/lakenasser.htm
Source of pictures • http://www.lonelyplanet.com/worldguide/ • http://www.earthkam.ucsd.edu/public/images/whitenile.shtml • http://www.jeffblundell.com/bluenile.html • http://www.joshandnic.com/Egypt/pages/57%20Sunset%20on%20the%20Nile.html • http://tsking.lausd.k12.ca.us/~mfamighetti
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