Blue Nile
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- This article is about the African river; for the Sudanese state, see Blue Nile, Sudan; for the Scottish pop act see The Blue Nile.
The Blue Nile is a river originating from the legendary Springs of Sakala upstream of Lake Tana in Ethiopia at an altitude of approximately 1,800 m (5,940 ft), joins the White Nile at Khartoum, Sudan and, as the Nile, flows through Egypt to the Mediterranean Sea at Alexandria. The Blue Nile is so-called because its water is visibly purer for most of the year than the grey-coloured water of the White Nile. The river is called the Abbai in Ethiopia and the Al Bahr al-Azraq in Sudan. The distance from its source to its confluence is variously reported as 1,460 and 1,600 km (907 and 1,000 mi). The uncertainty over its length might partially result from the fact that it flows through virtually impenetrable gorges cut in the the Ethiopian highlands to a depth of some 1,500 m (4950 ft) – a depth comparable to that of the Grand Canyon in the United States.
The Blue Nile flows generally south from Lake Tana and then west across Ethiopia and northwest into Sudan. Within 30 km (18.6 mi) of its source at Lake Tana the river enters a canyon which it does not leave for 400 km. This gorge is a tremendous obstacle for travel and communication from the north half of Ethiopia to the southern half. The power of the Blue Nile may best be appreciated at Tissisat Falls, which are 45 m (148 ft) high, located about 40 km (25 mi).
The flow of the Blue Nile reaches maximum volume in the rainy season (from June to September), when it supplies about two thirds of the water of the Nile proper. The Blue Nile, along with that of the Atbara to the north, which also flows out of the Ethiopian highlands, were responsible the annual Nile floods that contributed to the fertility of the Nile Valley and the consequent rise of ancient Egyptian civilization and Egyptian Mythology. With the completion in 1970 of the Aswan High Dam in Egypt, the Nile floods ended.
The first European to see the Blue Nile in Ethiopia is reported to have been a Portuguese priest who traveled to the area in the early 1600's. It took almost another 360 years before the gorge of the Nile was completely mapped. The river was not navigated along its entire length until 2004, when a four-month expedition succeeded in rafting the Blue Nile rapids.
The Blue Nile is vital to the livelihood of Egypt. Almost 60% of the water that reaches Egypt originates from the Blue Nile branch of the great river. The river is also an important resource for Sudan, where the Roseires and Sennar dams produce 80% of the country's power. These dams also help irrigate the Gezira Plain, which is most famous for its high quality cotton. The region also produces wheat, and animal feed crops.
Rafting Down the Blue Nile (http://www.npr.org/templates/story/story.php?storyId=1854297/)da:Den Blå Nil et:Sinine Niilus es:Nilo Azul it:Abai nl:Blauwe Nijl pl:Nil Błękitny ru:Голубой Нил (река) sl:Modri Nil