Atbara (sometimes Atbarah ) ( Arabic : عطبرة ʿAṭbarah) is a city located in River Nile State in northeastern Sudan .
134-595: Because of its links to the railway industry, Atbara is also known as the 'Railway City'. Atbara's population was recorded as 134,586 during the 2008 census. The confluence of the Nile and its most northern tributary, the Atbarah River (Bahr-el-Aswad, or Black River) was a strategic location for military operations. in the year 1619 Atbara was conquered and sacked by forces of the Ethiopian Empire . In
268-582: A lake , an ocean , or another river. A stream refers to water that flows in a natural channel , a geographic feature that can contain flowing water. A stream may also be referred to as a watercourse. The study of the movement of water as it occurs on Earth is called hydrology , and their effect on the landscape is covered by geomorphology . Rivers are part of the water cycle , the continuous processes by which water moves about Earth. This means that all water that flows in rivers must ultimately come from precipitation . The sides of rivers have land that
402-547: A trip hammer , and grind grains with a millstone . In the Middle Ages , water mills began to automate many aspects of manual labor , and spread rapidly. By 1300, there were at least 10,000 mills in England alone. A medieval watermill could do the work of 30–60 human workers. Water mills were often used in conjunction with dams to focus and increase the speed of the water. Water wheels continued to be used up to and through
536-433: A Turkish officer, Selim Bimbashi, were made between 1839 and 1842, and two got to the point about 30 kilometres (20 miles) beyond the present port of Juba , where the country rises and rapids make navigation very difficult. Lake Victoria was first sighted by Europeans in 1858 when British explorer John Hanning Speke reached its southern shore while traveling with Richard Francis Burton to explore central Africa and locate
670-740: A boat along certain stretches. In these religions, such as that of the Altai in Russia , the river is considered a living being that must be afforded respect. Rivers are some of the most sacred places in Hinduism. There is archeological evidence that mass ritual bathing in rivers at least 5,000 years ago in the Indus river valley . While most rivers in India are revered, the Ganges is most sacred. The river has
804-515: A central role in various Hindu myths, and its water is said to have properties of healing as well as absolution from sins. Hindus believe that when the cremated remains of a person is released into the Ganges, their soul is released from the mortal world. Freshwater fish make up 40% of the world's fish species, but 20% of these species are known to have gone extinct in recent years. Human uses of rivers make these species especially vulnerable. Dams and other engineered changes to rivers can block
938-408: A continuous flow of water throughout the year. This may be because an arid climate is too dry depending on the season to support a stream, or because a river is seasonally frozen in the winter (such as in an area with substantial permafrost ), or in the headwaters of rivers in mountains, where snowmelt is required to fuel the river. These rivers can appear in a variety of climates, and still provide
1072-767: A distance of 20 days' journey till it reaches the nearest Ethiopians." Modern exploration of the Nile basin began with the conquest of the northern and central Sudan by the Ottoman viceroy of Egypt, Muhammad Ali , and his sons from 1821 onward. As a result of this, the Blue Nile was known as far as its exit from the Ethiopian foothills and the White Nile as far as the mouth of the Sobat River. Three expeditions under
1206-468: A factor of 15 at Aswan. Peak flows of over 8,212 m /s (290,000 cu ft/s) occurred during late August and early September, and minimum flows of about 552 m /s (19,500 cu ft/s) occurred during late April and early May. The Bahr al Ghazal and the Sobat River are the two most important tributaries of the White Nile in terms of discharge. The Bahr al Ghazal's drainage basin
1340-564: A habitat for aquatic life and perform other ecological functions. Subterranean rivers may flow underground through flooded caves. This can happen in karst systems, where rock dissolves to form caves. These rivers provide a habitat for diverse microorganisms and have become an important target of study by microbiologists . Other rivers and streams have been covered over or converted to run in tunnels due to human development. These rivers do not typically host any life, and are often used only for stormwater or flood control. One such example
1474-495: A large scale. This has been attributed to unusually large floods destroying infrastructure; however, there is evidence that permanent changes to climate causing higher aridity and lower river flow may have been the determining factor in what river civilizations succeeded or dissolved. Water wheels began to be used at least 2,000 years ago to harness the energy of rivers. Water wheels turn an axle that can supply rotational energy to move water into aqueducts , work metal using
SECTION 10
#17327655614241608-556: A peak in the 1970s, when between two or three dams were completed every day, and has since begun to decline. New dam projects are primarily focused in China , India , and other areas in Asia . The first civilizations of Earth were born on floodplains between 5,500 and 3,500 years ago. The freshwater, fertile soil, and transportation provided by rivers helped create the conditions for complex societies to emerge. Three such civilizations were
1742-891: A ritualistic sense has been compared to the Christian ritual of baptism , famously the Baptism of Jesus in the Jordan River . Floods also appear in Norse mythology , where the world is said to emerge from a void that eleven rivers flowed into. Aboriginal Australian religion and Mesoamerican mythology also have stories of floods, some of which contain no survivors, unlike the Abrahamic flood. Along with mythological rivers, religions have also cared for specific rivers as sacred rivers. The Ancient Celtic religion saw rivers as goddesses. The Nile had many gods attached to it. The tears of
1876-425: A river can take several forms. Tidal rivers (often part of an estuary ) have their levels rise and fall with the tide . Since the levels of these rivers are often already at or near sea level, the flow of alluvium and the brackish water that flows in these rivers may be either upriver or downriver depending on the time of day. Rivers that are not tidal may form deltas that continuously deposit alluvium into
2010-460: A section of the river behind them into a lake or reservoir. This can provide nearby cities with a predictable supply of drinking water. Hydroelectricity is desirable as a form of renewable energy that does not require any inputs beyond the river itself. Dams are very common worldwide, with at least 75,000 higher than 6 feet (1.8 m) in the U.S. Globally, reservoirs created by dams cover 193,500 square miles (501,000 km ). Dam-building reached
2144-438: A water body is that body's riparian zone . Plants in the riparian zone of a river help stabilize its banks to prevent erosion and filter alluvium deposited by the river on the shore, including processing the nitrogen and other nutrients it contains. Forests in a riparian zone also provide important animal habitats . River ecosystems have also been categorized based on the variety of aquatic life they can sustain, also known as
2278-445: Is a tributary , and the place they meet is a confluence . Rivers must flow to lower altitudes due to gravity . The bed of a river is typically within a river valley between hills or mountains . Rivers flowing through an impermeable section of land such as rocks will erode the slopes on the sides of the river. When a river carves a plateau or a similar high-elevation area, a canyon can form, with cliffs on either side of
2412-504: Is also important for the lumber industry , as logs can be shipped via river. Countries with dense forests and networks of rivers like Sweden have historically benefited the most from this method of trade. The rise of highways and the automobile has made this practice less common. One of the first large canals was the Canal du Midi , connecting rivers within France to create a path from
2546-465: Is an archaeological site located in alluvial deposits formed by an ancient channel of the Nile in the Affad region of southern Dongola Reach , Sudan. There are two theories about the age of the integrated Nile. One is that the integrated drainage of the Nile is of young age and that the Nile basin was formerly broken into series of separate basins, only the most northerly of which fed a river following
2680-514: Is an ancient dam built on the Nile 4,500 years ago. The Ancient Roman civilization used aqueducts to transport water to urban areas . Spanish Muslims used mills and water wheels beginning in the seventh century. Between 130 and 1492, larger dams were built in Japan, Afghanistan, and India, including 20 dams higher than 15 metres (49 ft). Canals began to be cut in Egypt as early as 3000 BC, and
2814-642: Is approximately 1,218 m /s (43,000 cu ft/s) in October and minimum flow is about 609 m /s (21,500 cu ft/s) in April. This fluctuation is caused by the substantial variation in the flow of the Sobat, which has a minimum flow of about 99 m /s (3,500 cu ft/s) in March and a peak flow of over 680 m /s (24,000 cu ft/s) in October. During the dry season (January to June)
SECTION 20
#17327655614242948-448: Is at a higher elevation than the river itself, and in these areas, water flows downhill into the river. The headwaters of a river are the smaller streams that feed a river, and make up the river's source. These streams may be small and flow rapidly down the sides of mountains . All of the land uphill of a river that feeds it with water in this way is in that river's drainage basin or watershed. A ridge of higher elevation land
3082-405: Is because any natural impediment to the flow of the river may cause the current to deflect in a different direction. When this happens, the alluvium carried by the river can build up against this impediment, redirecting the course of the river. The flow is then directed against the opposite bank of the river, which will erode into a more concave shape to accommodate the flow. The bank will still block
3216-453: Is correlated with and thus can be used to predict certain data points related to rivers, such as the size of the drainage basin (drainage area), and the length of the channel. The ecosystem of a river includes the life that lives in its water, on its banks, and in the surrounding land. The width of the channel of a river, its velocity, and how shaded it is by nearby trees. Creatures in a river ecosystem may be divided into many roles based on
3350-703: Is in Egypt. Below the Aswan Dam , at the northern limit of Lake Nasser, the Nile resumes its historic course. North of Cairo , the Nile splits into two branches (or distributaries) that feed the Mediterranean: the Rosetta Branch to the west and the Damietta to the east, forming the Nile Delta . The annual sediment transport by the Nile in Egypt has been quantified. Below the confluence with
3484-497: Is in part because of a projected loss of snowpack in mountains, meaning that melting snow can't replenish rivers during warm summer months, leading to lower water levels. Lower-level rivers also have warmer temperatures, threatening species like salmon that prefer colder upstream temperatures. Attempts have been made to regulate the exploitation of rivers to preserve their ecological functions. Many wetland areas have become protected from development. Water restrictions can prevent
3618-562: Is much reduced. The original station and unusual dome-shaped houses of railway workers remain. The first trade union in Sudan formed in 1946 among railroad workers in Atbara. Perhaps because of the influence of the railway unions, Atbara is also considered by many to be the home of Sudanese communism. Jaafar Nimeiri , Sudan's president from 1969 to 1985, alternated between communism, capitalism, and Islamic fundamentalism – depending on who he
3752-402: Is part of permafrost ice caps, or trace amounts of water vapor in the atmosphere. However, there is evidence that rivers flowed on Mars for at least 100,000 years. The Hellas Planitia is a crater left behind by an impact from an asteroid. It has sedimentary rock that was formed 3.7 billion years ago, and lava fields that are 3.3 billion years old. High resolution images of the surface of
3886-633: Is rarely static, the exact location of a river border may be called into question by countries. The Rio Grande between the United States and Mexico is regulated by the International Boundary and Water Commission to manage the right to fresh water from the river, as well as mark the exact location of the border. Up to 60% of fresh water used by countries comes from rivers that cross international borders. This can cause disputes between countries that live upstream and downstream of
4020-864: Is related to the rail lines. The Sudanese National Railway Company's headquarters are located in Atbara. The city also is home to one of Sudan's largest cement factories, the Atbara Cement Corporation. A well-known resident was Mandour Elmahdi , who wrote A Short History of the Sudan . [REDACTED] This article incorporates text from a publication now in the public domain : Chisholm, Hugh , ed. (1911). " Atbara ". Encyclopædia Britannica . Vol. 2 (11th ed.). Cambridge University Press. p. 823. [REDACTED] Media related to Atbarah at Wikimedia Commons 17°41′50″N 33°58′42″E / 17.69722°N 33.97833°E / 17.69722; 33.97833 Nile The Nile (also known as
4154-701: Is that of the Mississippi River , whose drainage basin covers 40% of the contiguous United States . The river was then used for shipping crops from the American Midwest and cotton from the American South to other states as well as the Atlantic Ocean. The role of urban rivers has evolved from when they were a center of trade, food, and transportation to modern times when these uses are less necessary. Rivers remain central to
Atbara - Misplaced Pages Continue
4288-553: Is the Sunswick Creek in New York City, which was covered in the 1800s and now exists only as a sewer-like pipe. While rivers may flow into lakes or man-made features such as reservoirs , the water they contain will always tend to flow down toward the ocean . However, if human activity siphons too much water away from a river for other uses, the riverbed may run dry before reaching the sea. The outlets mouth of
4422-572: Is the largest of any of the Nile's sub-basins, measuring 520,000 square kilometers (200,000 sq mi) in size, but it contributes a relatively small amount of water, about 2 m /s (71 cu ft/s) annually, because tremendous volumes of water are lost in the Sudd wetlands. The Sobat River, which joins the Nile a short distance below Lake No, drains about half as much land, 225,000 km (86,900 sq mi), but contributes 412 cubic meters per second (14,500 cu ft/s) annually to
4556-545: Is traditionally considered to be the headwaters stream. However, the Blue Nile is the source of most of the water of the Nile downstream, containing 80% of the water and silt . The White Nile is longer and rises in the Great Lakes region. It begins at Lake Victoria and flows through Uganda and South Sudan. The Blue Nile begins at Lake Tana in Ethiopia and flows into Sudan from the southeast. The two rivers meet at
4690-842: Is what typically separates drainage basins; water on one side of a ridge will flow into one set of rivers, and water on the other side will flow into another. One example of this is the Continental Divide of the Americas in the Rocky Mountains . Water on the western side of the divide flows into the Pacific Ocean , whereas water on the other side flows into the Atlantic Ocean . Not all precipitation flows directly into rivers; some water seeps into underground aquifers . These, in turn, can still feed rivers via
4824-599: The 2024 Summer Olympics . Another example is the restoration of the Isar in Munich from being a fully canalized channel with hard embankments to being wider with naturally sloped banks and vegetation. This has improved wildlife habitat in the Isar, and provided more opportunities for recreation in the river. As a natural barrier , rivers are often used as a border between countries , cities, and other territories . For example,
4958-487: The Atlantic Ocean to the Mediterranean Sea . The nineteenth century saw canal-building become more common, with the U.S. building 4,400 miles (7,100 km) of canals by 1830. Rivers began to be used by cargo ships at a larger scale, and these canals were used in conjunction with river engineering projects like dredging and straightening to ensure the efficient flow of goods. One of the largest such projects
5092-673: The Battle of Atbara , fought on 8 April 1898 near Nakheila, on the north bank of the river, Lord Kitchener 's Anglo-Egyptian army defeated the Mahdist forces, commanded by Amir Mahmud Ahmad. Kitchener's strengthened position led to a decisive victory at the Battle of Omdurman on 2 September 1898, giving the British control over the Sudan. The town was the centre of the Sudanese railway industry . Few trains are made here now and rail traffic
5226-644: The Democratic Republic of the Congo , Tanzania , Burundi , Rwanda , Uganda , Kenya , Ethiopia , Eritrea , South Sudan , Sudan , and Egypt . In particular, the Nile is the primary water source of Egypt, Sudan and South Sudan. The Nile is an important economic driver supporting agriculture and fishing. The Nile has two major tributaries : the White Nile and the Blue Nile . The White Nile
5360-501: The Industrial Revolution as a source of power for textile mills and other factories, but were eventually supplanted by steam power . Rivers became more industrialized with the growth of technology and the human population . As fish and water could be brought from elsewhere, and goods and people could be transported via railways , pre-industrial river uses diminished in favor of more complex uses. This meant that
5494-791: The Lamari River in New Guinea separates the Angu and the Fore people in New Guinea. The two cultures speak different languages and rarely mix. 23% of international borders are large rivers (defined as those over 30 meters wide). The traditional northern border of the Roman Empire was the Danube , a river that today forms the border of Hungary and Slovakia . Since the flow of a river
Atbara - Misplaced Pages Continue
5628-525: The Nile and the Ganges . The Quran describes these four rivers as flowing with water, milk, wine, and honey, respectively. The book of Genesis also contains a story of a great flood . Similar myths are present in the Epic of Gilgamesh , Sumerian mythology, and in other cultures. In Genesis, the flood's role was to cleanse Earth of the wrongdoing of humanity. The act of water working to cleanse humans in
5762-651: The Paleogene and Neogene Periods (66 million to 2.588 million years ago) a series of separate closed continental basins each occupied one of the major parts of the Sudanese Rift System: Mellut rift , White Nile rift , Blue Nile rift , Atbara rift and Sag El Naam rift . The Mellut Basin is nearly 12 kilometers (7.5 mi) deep at its central part. This rift is possibly still active, with reported tectonic activity in its northern and southern boundaries. The Sudd swamp which forms
5896-568: The River Continuum Concept . "Shredders" are organisms that consume this organic material. The role of a "grazer" or "scraper" organism is to feed on the algae that collects on rocks and plants. "Collectors" consume the detritus of dead organisms. Lastly, predators feed on living things to survive. The river can then be modeled by the availability of resources for each creature's role. A shady area with deciduous trees might experience frequent deposits of organic matter in
6030-627: The River Lethe to forget their previous life. Rivers also appear in descriptions of paradise in Abrahamic religions , beginning with the story of Genesis . A river beginning in the Garden of Eden waters the garden and then splits into four rivers that flow to provide water to the world. These rivers include the Tigris and Euphrates , and two rivers that are possibly apocryphal but may refer to
6164-720: The River Nile or Nile River ) is a major north-flowing river in northeastern Africa . It flows into the Mediterranean Sea . The Nile is the longest river in Africa. It has historically been considered the longest river in the world , though this has been contested by research suggesting that the Amazon River is slightly longer. Of the world's major rivers, the Nile is one of the smallest, as measured by annual flow in cubic metres of water. About 6,650 km (4,130 mi) long, its drainage basin covers eleven countries:
6298-736: The Sumerians in the Tigris–Euphrates river system , the Ancient Egyptian civilization in the Nile, and the Indus Valley Civilization on the Indus River . The desert climates of the surrounding areas made these societies especially reliant on rivers for survival, leading to people clustering in these areas to form the first cities . It is also thought that these civilizations were the first to organize
6432-485: The climate . The alluvium carried by rivers, laden with minerals, is deposited into the floodplain when the banks spill over, providing new nutrients to the soil, allowing them to support human activity like farming as well as a host of plant and animal life. Deposited sediment from rivers can form temporary or long-lasting fluvial islands . These islands exist in almost every river. About half of all waterways on Earth are intermittent rivers , which do not always have
6566-685: The cultural identity of cities and nations. Famous examples include the River Thames 's relationship to London , the Seine to Paris , and the Hudson River to New York City . The restoration of water quality and recreation to urban rivers has been a goal of modern administrations. For example, swimming was banned in the Seine for over 100 years due to concerns about pollution and the spread of E. coli , until cleanup efforts to allow its use in
6700-456: The discharge at any given point along the main stem depends on many factors including weather, diversions, evaporation and evapotranspiration , and groundwater flow. Upstream from Khartoum (to the south), the river is known as the White Nile , a term also used in a limited sense to describe the section between Lake No and Khartoum. At Khartoum, the river is joined by the Blue Nile . The White Nile starts in equatorial East Africa, and
6834-424: The discharge of a river, the amount of water passing through it at a particular time. The flow of a river can act as a means of transportation for plant and animal species, as well as a barrier. For example, the Amazon River is so wide in parts that the variety of species on either side of its basin are distinct. Some fish may swim upstream to spawn as part of a seasonal migration . Species that travel from
SECTION 50
#17327655614246968-430: The dry season ) an appreciable incoming surface flow for many kilometres upstream, and found a new source, giving the Nile a length of 6,758 km (4,199 mi). The White Nile leaves Lake Victoria at Ripon Falls near Jinja, Uganda , as the "Victoria Nile." It flows north for some 130 kilometers (81 mi) to Lake Kyoga . The last part of the approximately 200 kilometers (120 mi) river section starts from
7102-465: The extinction of some species, and lowered the amount of alluvium flowing through rivers. Decreased snowfall from climate change has resulted in less water available for rivers during the summer. Regulation of pollution, dam removal , and sewage treatment have helped to improve water quality and restore river habitats. A river is a natural flow of freshwater that flows on or through land towards another body of water downhill. This flow can be into
7236-436: The sea . The sediment yield of a river is the quantity of sand per unit area within a watershed that is removed over a period of time. The monitoring of the sediment yield of a river is important for ecologists to understand the health of its ecosystems, the rate of erosion of the river's environment, and the effects of human activity. Rivers rarely run in a straight direction, instead preferring to bend or meander . This
7370-521: The water table , the groundwater beneath the surface of the land stored in the soil . Water flows into rivers in places where the river's elevation is lower than that of the water table. This phenomenon is why rivers can still flow even during times of drought . Rivers are also fed by the melting of snow glaciers present in higher elevation regions. In summer months, higher temperatures melt snow and ice, causing additional water to flow into rivers. Glacier melt can supplement snow melt in times like
7504-502: The Bahr al Jabal at a small lagoon called Lake No , after which the Nile becomes known as the Bahr al Abyad , or the White Nile, from the whitish clay suspended in its waters. When the Nile floods it leaves a rich silty deposit which fertilizes the soil. The Nile no longer floods in Egypt since the completion of the Aswan Dam in 1970. An anabranch river, the Bahr el Zeraf , flows out of
7638-399: The Blue Nile begins in Ethiopia. Both branches are on the western flanks of the East African Rift . The source of the Blue Nile is Lake Tana in the Gish Abay region in the Ethiopian Highlands . The source of the White Nile, even after centuries of exploration, remains in dispute. The most remote source that is indisputably a source for the White Nile is the Kagera River ; however,
7772-451: The Blue Nile the only major tributary is the Atbarah River , also known as the Red Nile. Roughly halfway to the sea, it originates in Ethiopia north of Lake Tana , and is around 800 kilometers (500 mi) long. The Atbarah flows only while there is rain in Ethiopia and dries very rapidly. During the dry period of January to June, it typically dries up north of Khartoum . The Blue Nile ( Amharic : ዓባይ , ʿĀbay ) springs from Lake Tana in
7906-419: The Congo, but the Nile is not a border river at this point. After leaving Lake Albert, the river continues north through Uganda and is known as the Albert Nile . The White Nile flows into South Sudan just south of Nimule , where it is known as the Bahr al Jabal ("Mountain River" ). Just south of the town is the confluence with the Achwa River . The Bahr al Ghazal , 716 kilometers (445 mi) long, joins
8040-431: The Delta, and would have been pronounced ni-lo-he in the area around Memphis in the 8th century BCE. Hesiod at his Theogony refers to Nilus (Νεῖλος) as one of the Potamoi (river gods), son of Oceanus and Tethys . Another derivation of Nile might be related to the term Nil ( Sanskrit : नील , romanized : nila ; Egyptian Arabic : نيلة ), which refers to Indigofera tinctoria , one of
8174-407: The Earth. Water first enters rivers through precipitation , whether from rainfall, the runoff of water down a slope, the melting of glaciers or snow , or seepage from aquifers beneath the surface of the Earth. Rivers flow in channeled watercourses and merge in confluences to form drainage basins , areas where surface water eventually flows to a common outlet. Rivers have a great effect on
SECTION 60
#17327655614248308-414: The Ethiopian rainy season when rainfall is especially high in the Ethiopian Highlands ; the rest of the year, the great rivers draining Ethiopia into the Nile have a weaker flow. In harsh and arid seasons and droughts, the Blue Nile dries out completely. The flow of the Blue Nile varies considerably over its yearly cycle and is the main contribution to the large natural variation of the Nile flow. During
8442-444: The Ethiopian Highlands, satellite imagery was used to identify dry watercourses in the desert to the west of the Nile. A canyon, now filled by surface drift, represents the Eonile that flowed during 23–5.3 million years before present. The Eonile transported clastic sediments to the Mediterranean; several natural gas fields have been discovered within these sediments. During the late- Miocene Messinian salinity crisis , when
8576-436: The Ethiopian Highlands. The Blue Nile flows about 1,400 kilometres to Khartoum, where the Blue Nile and White Nile join to form the Nile. Ninety percent of the water and ninety-six percent of the transported sediment carried by the Nile come from the Atbarah and Blue Nile, both of which originate in Ethiopia, with fifty-nine percent of the water coming from the Blue Nile. The erosion and transportation of silt only occurs during
8710-412: The Kagera has tributaries that are in contention for the farthest source of the White Nile. Two start in Burundi: the Ruvyironza River (also known as the Luvironza) and the Rurubu River . In addition, in 2010, an exploration party in Rwanda went to a place described as the source of the Rukarara tributary, and by hacking a path up steep jungle-choked mountain slopes in the Nyungwe Forest found (in
8844-414: The Mediterranean Sea was a closed basin and evaporated to the point of being empty or nearly so, the Nile cut its course down to the new base level until it was several hundred metres below world ocean level at Aswan and 2,400 m (7,900 ft) below Cairo. This created a very long and deep canyon which was filled with sediment after the Mediterranean was recreated. At some point the sediments raised
8978-464: The Middle East and Africa, and described being told of the source of the Nile in Abyssinia (Ethiopia). Later in the 15th and 16th centuries, travelers to Ethiopia visited Lake Tana and the source of the Blue Nile in the mountains south of the lake. Supposedly, Paolo Trevisani ( c. 1452 –1483), a Venetian traveller in Ethiopia, wrote a journal of his travels to the origin of the Nile that has since been lost. Although James Bruce claimed to be
9112-407: The Nile near the southern point of the Great Bend. The Nile has been the lifeline of civilization in Egypt since the Stone Age , with most of the population and all of the cities of Egypt developing along those parts of the Nile valley lying north of Aswan. However, the Nile used to run much more westerly through what is now Wadi Hamim and Wadi al Maqar in Libya and flow into the Gulf of Sidra . As
9246-411: The Nile since ancient times. A tune, Hymn to the Nile , was created and sung by the ancient Egyptian peoples about the flooding of the Nile River and all of the miracles it brought to Ancient Egyptian civilization. Water buffalo were introduced from Asia, and the Assyrians introduced camels in the 7th century BCE. These animals were raised for meat and were domesticated and used for ploughing—or in
9380-403: The Nile valley north of the Aswan Dam . Nearly all the cultural and historical sites of Ancient Egypt developed and are found along river banks. The Nile is, with the Rhône and Po , one of the three Mediterranean rivers with the largest water discharge . The standard English names "White Nile" and "Blue Nile" refer to the river's source, derived from Arabic names formerly applied to only
9514-410: The Nile's Bahr al Jabal section and rejoins the White Nile. The flow rate of the Bahr al Jabal at Mongalla is almost constant throughout the year and averages 1,048 m /s (37,000 cu ft/s). After Mongalla, the Bahr Al Jabal enters the enormous swamps of the Sudd region. More than half of the Nile's water is lost in this swamp to evaporation and transpiration . The average flow rate of
9648-595: The Nile. When in flood the Sobat carries a large amount of sediment, adding greatly to the White Nile's color. The Yellow Nile is a former tributary that connected the Ouaddaï highlands of eastern Chad to the Nile River Valley c. 8000 to c. 1000 BCE . Its remains are known as the Wadi Howar . The wadi passes through Gharb Darfur near the northern border with Chad and meets up with
9782-600: The Sudanese capital of Khartoum . The northern section of the river flows north almost entirely through the Nubian Desert to Cairo and its large delta , and the river flows into the Mediterranean Sea at Alexandria . Egyptian civilization and Sudanese kingdoms have depended on the river and its annual flooding since ancient times. Most of the population and cities of Egypt lie along those parts of
9916-425: The Sudanese stretches that meet at Khartoum . In the ancient Egyptian language , the Nile is called Ḥꜥpy (Hapy) or Jtrw (Iteru), meaning "river". In Coptic , the word ⲫⲓⲁⲣⲟ , pronounced piaro ( Sahidic ) or phiaro ( Bohairic ), means "the river" (lit. p(h).iar-o "the.canal-great"), and comes from the same ancient name. In Nobiin , the river is called Áman Dawū , meaning "the great water". In Luganda ,
10050-554: The Sudd wetlands of South Sudan, the upper reaches of the White Nile remained largely unknown to the ancient Greeks and Romans. Vitruvius thought that source of the Nile was in Mauritania, on the "other" (south) side of the Atlas Mountains . Various expeditions failed to determine the river's source. Agatharchides records that in the time of Ptolemy II Philadelphus , a military expedition had penetrated far enough along
10184-408: The White Nile at the tails of the swamps is about 510 m /s (18,000 cu ft/s). From here it meets with the Sobat River at Malakal . On an annual basis, the White Nile upstream of Malakal contributes about 15% of the total outflow of the Nile. The average flow of the White Nile at Lake Kawaki Malakal, just below the Sobat River, is 924 m /s (32,600 cu ft/s); the peak flow
10318-460: The White Nile contributes between 70% and 90% of the total discharge from the Nile. Below Renk , the White Nile enters Sudan, it flows north to Khartoum and meets the Blue Nile. The course of the Nile in Sudan is distinctive. It flows over six groups of cataracts , from the sixth at Sabaloka just north of Khartoum northward to Abu Hamad . The tectonic uplift of the Nubian Swell diverts
10452-606: The afterlife. The east was thought of as a place of birth and growth, and the west was considered the place of death, as the god Ra , the Sun, underwent birth, death, and resurrection each day as he crossed the sky. Thus, all tombs were west of the Nile, because the Egyptians believed that in order to enter the afterlife, they had to be buried on the side that symbolized death. As the Nile was such an important factor in Egyptian life,
10586-482: The ancient calendar was even based on the three cycles of the Nile. These seasons, each consisting of four months of thirty days each, were called Akhet , Peret , and Shemu . Akhet, which means inundation, was the time of the year when the Nile flooded, leaving several layers of fertile soil behind, aiding in agricultural growth. Peret was the growing season, and Shemu, the last season, was the harvest season when there were no rains. Owing to their failure to penetrate
10720-521: The average highs exceed 40 °C (104 °F) during 7 months of the year. The annual average rainfall is 60 mm, mostly from July and August. Atbara is sunny, averaging 3,545 hours of bright sunshine per year or 81% of possible sunshine. The trans-African automobile route — the Cairo-Cape Town Highway passes through Atbara. Atbara is an important railway junction and railroad manufacturing centre, and most employment in Atbara
10854-695: The bodies of humans and animals worldwide, as well as in the soil, with potentially negative health effects. Research into how to remove it from the environment, and how harmful exposure is, is ongoing. Fertilizer from farms can lead to a proliferation of algae on the surface of rivers and oceans, which prevents oxygen and light from dissolving into water, making it impossible for underwater life to survive in these so-called dead zones . Urban rivers are typically surrounded by impermeable surfaces like stone, asphalt , and concrete. Cities often have storm drains that direct this water to rivers. This can cause flooding risk as large amounts of water are directed into
10988-411: The camels' case, carriage. Water was vital to both people and livestock. The Nile was also a convenient and efficient means of transportation for people and goods. The Nile was also an important part of ancient Egyptian spiritual life. Hapi was the god of the annual floods, and both he and the pharaoh were thought to control the flooding. The Nile was considered to be a causeway from life to death and
11122-479: The central part of the basin may still be subsiding. The White Nile Rift system, although shallower than the Bahr el Arab rift , is about 9 kilometers (5.6 mi) deep. Geophysical exploration of the Blue Nile Rift System estimated the depth of the sediments to be 5–9 kilometers (3.1–5.6 mi). These basins were not interconnected until their subsidence ceased, and the rate of sediment deposition
11256-405: The complete draining of rivers. Limits on the construction of dams, as well as dam removal , can restore the natural habitats of river species. Regulators can also ensure regular releases of water from dams to keep animal habitats supplied with water. Limits on pollutants like pesticides can help improve water quality. Today, the surface of Mars does not have liquid water. All water on Mars
11390-534: The course of the Blue Nile to determine that the summer floods were caused by heavy seasonal rainstorms in the Ethiopian Highlands, but no European of antiquity is known to have reached Lake Tana. The Tabula Rogeriana depicted the source as three lakes in 1154. Europeans began to learn about the origins of the Nile in the 14th century when the Pope sent monks as emissaries to Mongolia who passed India,
11524-492: The development of Egyptian civilization. Because the river overflowed its banks annually and deposited new layers of silt, the surrounding land was very fertile. The Ancient Egyptians cultivated and traded wheat, flax , papyrus and other crops around the Nile. Wheat was a crucial crop in the famine-plagued Middle East. This trading system secured Egypt's diplomatic relationships with other countries and contributed to economic stability. Far-reaching trade has been carried on along
11658-402: The dry season the natural discharge of the Blue Nile can be as low as 113 m /s (4,000 cu ft/s), although upstream dams regulate the flow of the river. During the wet season, the peak flow of the Blue Nile often exceeds 5,663 m /s (200,000 cu ft/s) in late August (a difference of a factor of 50). Before the placement of dams on the river the yearly discharge varied by
11792-436: The effect of normalizing the effects of rivers; the greatest floods are smaller and more predictable, and larger sections are open for navigation by boats and other watercraft. A major effect of river engineering has been a reduced sediment output of large rivers. For example, the Mississippi River produced 400 million tons of sediment per year. Due to the construction of reservoirs , sediment buildup in man-made levees , and
11926-410: The etymology is disputed. Homer called the river Αἴγυπτος , Aiguptos , but in subsequent periods, Greek authors referred to its lower course as Neilos ; this term became generalized for the entire river system. Thus, the name may derive from Ancient Egyptian expression n ꜣ r ꜣ w-ḥ ꜣ w(t) (lit. 'the mouths of the front parts'), which referred specifically to the branches of the Nile transversing
12060-508: The first European to have visited the headwaters, modern writers give the credit to the Jesuit Pedro Páez . Páez's account of the source of the Nile is a long and vivid account of Ethiopia. It was published in full only in the early 20th century, although it was featured in works of Páez's contemporaries, including Baltazar Téllez, Athanasius Kircher and Johann Michael Vansleb . Europeans had been resident in Ethiopia since
12194-826: The first human civilizations . The organisms that live around or in a river such as fish , aquatic plants , and insects have different roles, including processing organic matter and predation . Rivers have produced abundant resources for humans, including food , transportation , drinking water , and recreation. Humans have engineered rivers to prevent flooding, irrigate crops, perform work with water wheels , and produce hydroelectricity from dams. People associate rivers with life and fertility and have strong religious, political, social, and mythological attachments to them. Rivers and river ecosystems are threatened by water pollution , climate change , and human activity. The construction of dams, canals , levees , and other engineered structures has eliminated habitats, has caused
12328-451: The fish zonation concept. Smaller rivers can only sustain smaller fish that can comfortably fit in its waters, whereas larger rivers can contain both small fish and large fish. This means that larger rivers can host a larger variety of species. This is analogous to the species-area relationship , the concept of larger habitats being host to more species. In this case, it is known as the species-discharge relationship, referring specifically to
12462-673: The floating of wood on rivers to transport it, was especially important. Rivers also were an important source of drinking water . For civilizations built around rivers, fish were an important part of the diet of humans. Some rivers supported fishing activities, but were ill-suited to farming, such as those in the Pacific Northwest . Other animals that live in or near rivers like frogs , mussels , and beavers could provide food and valuable goods such as fur . Humans have been building infrastructure to use rivers for thousands of years. The Sadd el-Kafara dam near Cairo , Egypt,
12596-412: The flow of the river beneath its surface. These help rivers flow straighter by increasing the speed of the water at the middle of the channel, helping to control floods. Levees are also used for this purpose. They can be thought of as dams constructed on the sides of rivers, meant to hold back water from flooding the surrounding area during periods of high rainfall. They are often constructed by building up
12730-399: The flow, causing it to reflect in the other direction. Thus, a bend in the river is created. Rivers may run through low, flat regions on their way to the sea. These places may have floodplains that are periodically flooded when there is a high level of water running through the river. These events may be referred to as "wet seasons' and "dry seasons" when the flooding is predictable due to
12864-650: The form of leaves. In this type of ecosystem, collectors and shredders will be most active. As the river becomes deeper and wider, it may move slower and receive more sunlight . This supports invertebrates and a variety of fish , as well as scrapers feeding on algae. Further downstream, the river may get most of its energy from organic matter that was already processed upstream by collectors and shredders. Predators may be more active here, including fish that feed on plants, plankton , and other fish. The flood pulse concept focuses on habitats that flood seasonally, including lakes and marshes . The land that interfaces with
12998-508: The goddess Isis were said to be the cause of the river's yearly flooding, itself personified by the goddess Hapi . Many African religions regard certain rivers as the originator of life. In Yoruba religion , Yemọja rules over the Ogun River in modern-day Nigeria and is responsible for creating all children and fish. Some sacred rivers have religious prohibitions attached to them, such as not being allowed to drink from them or ride in
13132-459: The great lakes. Believing he had found the source of the Nile on seeing this "vast expanse of open water" for the first time, Speke named the lake after Queen Victoria . Burton, recovering from illness and resting further south on the shores of Lake Tanganyika , was outraged that Speke claimed to have proven his discovery to be the true source of the Nile when Burton regarded this as still unsettled. A quarrel ensued which sparked intense debate within
13266-428: The irrigation of desert environments for growing food. Growing food at scale allowed people to specialize in other roles, form hierarchies, and organize themselves in new ways, leading to the birth of civilization. In pre-industrial society , rivers were a source of transportation and abundant resources. Many civilizations depended on what resources were local to them to survive. Shipping of commodities, especially
13400-439: The lake's northern shore. River A river is a natural freshwater stream that flows on land or inside caves towards another body of water at a lower elevation , such as an ocean , lake , or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle , the processes by which water moves around
13534-566: The landscape around them. They may regularly overflow their banks and flood the surrounding area, spreading nutrients to the surrounding area. Sediment or alluvium carried by rivers shapes the landscape around it, forming deltas and islands where the flow slows down. Rivers rarely run in a straight line, instead, they bend or meander ; the locations of a river's banks can change frequently. Rivers get their alluvium from erosion , which carves rock into canyons and valleys . Rivers have sustained human and animal life for millennia, including
13668-609: The late 15th century, and one of them may have visited the headwaters even earlier without leaving a written trace. The Portuguese João Bermudes published the first description of the Tis Issat Falls in his 1565 memoirs, compared them to the Nile Falls alluded to in Cicero 's De Republica . Jerónimo Lobo describes the source of the Blue Nile, visiting shortly after Pedro Páez. Telles also uses his account. The White Nile
13802-434: The late summer, when there may be less snow left to melt, helping to ensure that the rivers downstream of the glaciers have a continuous supply of water. Rivers flow downhill, with their direction determined by gravity . A common misconception holds that all or most rivers flow from North to South, but this is not true. As rivers flow downstream, they eventually merge to form larger rivers. A river that feeds into another
13936-474: The level of river branching in a drainage basin. Several systems of stream order exist, one of which is the Strahler number . In this system, the first tributaries of a river are 1st order rivers. When two 1st order rivers merge, the resulting river is 2nd order. If a river of a higher order and a lower order merge, the order is incremented from whichever of the previous rivers had the higher order. Stream order
14070-561: The local ecosystems of rivers needed less protection as humans became less reliant on them for their continued flourishing. River engineering began to develop projects that enabled industrial hydropower , canals for the more efficient movement of goods, as well as projects for flood prevention . River transportation has historically been significantly cheaper and faster than transportation by land. Rivers helped fuel urbanization as goods such as grain and fuel could be floated downriver to supply cities with resources. River transportation
14204-580: The main Nile during the 70,000–80,000 years B.P. wet period. The White Nile system in Bahr El Arab and White Nile Rifts remained a closed lake until the connection of the Victoria Nile to the main system some 12,500 years ago during the African humid period . The Greek historian Herodotus wrote that "Egypt was the gift of the Nile". An unending source of sustenance, it played a crucial role in
14338-407: The mechanical shadoof began to be used to raise the elevation of water. Drought years harmed crop yields, and leaders of society were incentivized to ensure regular water and food availability to remain in power. Engineering projects like the shadoof and canals could help prevent these crises. Despite this, there is evidence that floodplain-based civilizations may have been abandoned occasionally at
14472-400: The migration routes of fish and destroy habitats. Rivers that flow freely from headwaters to the sea have better water quality, and also retain their ability to transport nutrient-rich alluvium and other organic material downstream, keeping the ecosystem healthy. The creation of a lake changes the habitat of that portion of water, and blocks the transportation of sediment, as well as preventing
14606-399: The natural meandering of the river. Dams block the migration of fish such as salmon for which fish ladder and other bypass systems have been attempted, but these are not always effective. Pollution from factories and urban areas can also damage water quality. " Per- and polyfluoroalkyl substances (PFAS) is a widely used chemical that breaks down at a slow rate. It has been found in
14740-429: The natural terrain with soil or clay. Some levees are supplemented with floodways, channels used to redirect floodwater away from farms and populated areas. Dams restrict the flow of water through a river. They can be built for navigational purposes, providing a higher level of water upstream for boats to travel in. They may also be used for hydroelectricity , or power generation from rivers. Dams typically transform
14874-513: The original sources of indigo dye . Another may be Nymphaea caerulea , known as "The Sacred Blue Lily of the Nile", which was found scattered over Tutankhamun 's corpse when it was excavated in 1922. Another possible etymology derives from the Semitic term Nahal , meaning "river". Old Libyan has the term lilu , meaning water (in modern Berber ilel ⵉⵍⴻⵍ means sea ). With a total length of about 6,650 km (4,130 mi) between
15008-425: The plain show evidence of a river network, and even river deltas. These images reveal channels formed in the rock, recognized by geologists who study rivers on Earth as being formed by rivers, as well as "bench and slope" landforms, outcroppings of rock that show evidence of river erosion. Not only do these formations suggest that rivers once existed, but that they flowed for extensive time periods, and were part of
15142-585: The present course of the Nile in Egypt and Sudan. Rushdi Said postulates that Egypt supplied most of the waters of the Nile during the early part of its history. The other theory is that the drainage from Ethiopia via rivers equivalent to the Blue Nile, the Atbara and the Takazze flowed to the Mediterranean via the Egyptian Nile since well back into Tertiary times. Salama suggests that during
15276-602: The railway district, Almurabaat, Alsawdana and Almatar. Umbukole was originally the name given to a capital city in a northern state in Kurti county. It is now mostly remembered as the name of a small district in Atbara. One of the major districts of Atbara is Al-Dakhla (الداخلة) in Arabic. Some still use the name Al-Dakhla referring to Atbara. Atbara has a hot desert climate ( Köppen climate classification BWh ). The annual mean temperature reaches over 30 °C (86 °F) and
15410-462: The region of Lake Victoria and the Mediterranean Sea , the Nile is among the longest rivers on Earth. The drainage basin of the Nile covers 3,254,555 square kilometers (1,256,591 sq mi), about 10% of the area of Africa. Compared to other major rivers, though, the Nile carries little water (5% of that of the Congo River , for example). The Nile basin is complex, and because of this,
15544-448: The removal of natural banks replaced with revetments , this sediment output has been reduced by 60%. The most basic river projects involve the clearing of obstructions like fallen trees. This can scale up to dredging , the excavation of sediment buildup in a channel, to provide a deeper area for navigation. These activities require regular maintenance as the location of the river banks changes over time, floods bring foreign objects into
15678-536: The reverse, death and destruction, especially through floods . This power has caused rivers to have a central role in religion , ritual , and mythology . In Greek mythology , the underworld is bordered by several rivers. Ancient Greeks believed that the souls of those who perished had to be borne across the River Styx on a boat by Charon in exchange for money. Souls that were judged to be good were admitted to Elysium and permitted to drink water from
15812-632: The river is called Kiira or Kiyira . In Runyoro , it is called Kihiira . In Egyptian Arabic , the Nile is called en-Nīl , while in Standard Arabic it is called an-Nīl . In Biblical Hebrew , it is הַיְאוֹר , Ha-Ye'or or הַשִׁיחוֹר , Ha-Shiḥor . The English name Nile and the Arabic names en-Nîl and an-Nîl both derive from the Latin Nilus and the Ancient Greek Νεῖλος . Beyond that, however,
15946-618: The river south-west for over 300 km, following the structure of the Central African Shear Zone embracing the Bayuda Desert . At Al Dabbah it resumes its northward course towards the first cataract at Aswan forming the S-shaped Great Bend of the Nile mentioned by Eratosthenes . In the north of Sudan, the river enters Lake Nasser (known in Sudan as Lake Nubia), the larger part of which
16080-468: The river, and natural sediment buildup continues. Artificial channels are often constructed to "cut off" winding sections of a river with a shorter path, or to direct the flow of a river in a straighter direction. This effect, known as channelization, has made the distance required to traverse the Missouri River in 116 kilometres (72 mi) shorter. Dikes are channels built perpendicular to
16214-552: The river. Areas of a river with softer rock weather faster than areas with harder rock, causing a difference in elevation between two points of a river. This can cause the formation of a waterfall as the river's flow falls down a vertical drop. A river in a permeable area does not exhibit this behavior and may even have raised banks due to sediment. Rivers also change their landscape through their transportation of sediment , often known as alluvium when applied specifically to rivers. This debris comes from erosion performed by
16348-569: The river. A country that is downstream of another may object to the upstream country diverting too much water for agricultural uses, pollution, as well as the creation of dams that change the river's flow characteristics. For example, Egypt has an agreement with Sudan requiring a specific minimum volume of water to pass into the Nile yearly over the Aswan Dam , to maintain both countries access to water. The importance of rivers throughout human history has given them an association with life and fertility . They have also become associated with
16482-585: The riverbed sufficiently for the river to overflow westward into a depression to create Lake Moeris . Lake Tanganyika drained northwards into the Nile until the Virunga Volcanoes blocked its course in Rwanda. The Nile was much longer at that time, with its furthest headwaters in northern Zambia. The currently existing Nile first flowed during the former parts of the Würm glaciation period. Affad 23
16616-457: The rivers themselves, debris swept into rivers by rainfall, as well as erosion caused by the slow movement of glaciers. The sand in deserts and the sediment that forms bar islands is from rivers. The particle size of the debris is gradually sorted by the river, with heavier particles like rocks sinking to the bottom, and finer particles like sand or silt carried further downriver . This sediment may be deposited in river valleys or carried to
16750-412: The rivers. Due to these impermeable surfaces, these rivers often have very little alluvium carried in them, causing more erosion once the river exits the impermeable area. It has historically been common for sewage to be directed directly to rivers via sewer systems without being treated, along with pollution from industry. This has resulted in a loss of animal and plant life in urban rivers, as well as
16884-407: The scientific community and interest by other explorers keen to either confirm or refute Speke's discovery. British explorer and missionary David Livingstone pushed too far west and entered the Congo River system instead. It was ultimately Welsh-American explorer Henry Morton Stanley who confirmed Speke's discovery, circumnavigating Lake Victoria and reporting the great outflow at Ripon Falls on
17018-409: The sea from their mouths. Depending on the activity of waves, the strength of the river, and the strength of the tidal current, the sediment can accumulate to form new land. When viewed from above, a delta can appear to take the form of several triangular shapes as the river mouth appears to fan out from the original coastline . In hydrology , a stream order is a positive integer used to describe
17152-588: The sea level rose at the end of the most recent ice age , the stream which is now the northern Nile captured the ancestral Nile near Asyut . This change in climate also led to the current extents of the Sahara desert, around 3400 BCE. The Giza pyramid complex originally overlooked a branch of the Nile that no longer exists. This branch was highest during the African Humid Period . The existing Nile has five earlier phases: Flowing north from
17286-414: The sea to breed in freshwater rivers are anadromous. Salmon are an anadromous fish that may die in the river after spawning, contributing nutrients back to the river ecosystem. Modern river engineering involves a large-scale collection of independent river engineering structures that have the goal of flood control , improved navigation, recreation, and ecosystem management. Many of these projects have
17420-519: The spread of waterborne diseases such as cholera . In modern times, sewage treatment and controls on pollution from factories have improved the water quality of urban rivers. Climate change can change the flooding cycles and water supply available to rivers. Floods can be larger and more destructive than expected, causing damage to the surrounding areas. Floods can also wash unhealthy chemicals and sediment into rivers. Droughts can be deeper and longer, causing rivers to run dangerously low. This
17554-560: The western shores of the lake and flows at first to the west until just south of Masindi Port , where the river turns north, then makes a great half circle to the east and north to Karuma Falls . For the remaining part, it flows westerly through the Murchison Falls until it reaches the northern shores of Lake Albert where it forms a significant river delta. Lake Albert is on the border of the Democratic Republic of
17688-574: Was enough to fill and connect them. The Egyptian Nile connected to the Sudanese Nile, which captures the Ethiopian and Equatorial headwaters during the current stages of tectonic activity in the Eastern, Central and Sudanese Rift systems. The connection of the different Niles occurred during cyclic wet periods. The Atbarah overflowed its closed basin during the wet periods that occurred about 100,000 to 120,000 years ago. The Blue Nile connected to
17822-597: Was even less understood. The ancients mistakenly believed that the Niger River represented the upper reaches of the White Nile. For example, Pliny the Elder writes that the Nile had its origins "in a mountain of lower Mauretania ", flowed above ground for "many days" distance, then went underground, reappeared as a large lake in the territories of the Masaesyli , then sank again below the desert to flow underground "for
17956-551: Was trying to get on his side and extract money from – and the communist phase had its stronghold around Atbara. Atbara was also the starting point for mobilizations against the regime in December 2018. Atbara is located at the junction of the Nile and Atbarah rivers. Atbara is made up of several districts including Umbukole district which was home to the First Higher School in Atbara. Other districts include
#423576