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The Nile becomes increasingly important the farther north it flows into Sudan and Egypt. This is because it brings water to these regions which lie in Earth's greatest and most desolate desert, the Sahara. Without the blessing of Nile water, Egypt today would be as empty as the rest of the Sahara, and civilization would have had to begin elsewhere. Because of the Nile, Egypt was one of the wonders of ancient times, providing inspiration essential for the development of societies in ancient Greece and Israel which in turn provided the basis for the philosophical, scientific and religious outlooks that define Western Civilization. The continued blessings of the Nile allow Egypt to continue today as one of the largest and most powerful nations of Africa and the Middle East. There can be little doubt that if the Nile did not flow through Egypt, the human endeavor we call civilization would be a very different thing than it is today, if it existed at all. |
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In the same way that the Nile valley and delta define Egypt, changes in the nature of the river define Egypt's natural frontier. North of Aswan, the river has a gentle gradient, dropping 1m in every 13 km. It can be navigated by boats powered by sails or oars, and it is flanked by a floodplain that widens progressively to the north, then fans out to make the delta. The scale of agriculture increases as the area of cultivatable land increases northward, and this allows for larger populations to the north. Aswan marks the first cataract, significant because this was a great natural obstruction to travel upstream by sailboats or those powered by oars. The cataract itself is an obstruction of the river caused by a series of rocky rapids and small islands. Upstream for hundreds of miles from Aswan the floodplain was narrow and could not be cultivated to support a great population. In the Old Testament (Ezekiel 29:10) it is stated that Egypt ends and Ethiopia begins at Syene, the ancient name for Aswan. It was only at the beginning of New Kingdom times about 1200 B.C.) that Egyptian armies ventured very far south of the first cataract. More recently the construction of the High Dam at Aswan emphasizes the fact that Egyptians have always felt that their country ended and Africa began at the first cataract. The 350km long stretch of the Nile from the Sudan border to 7km upstream from Aswan once flowed through a narrow valley bordered by sandstone cliffs but is now covered by the waters of the artificial lake known to Egyptians as Lake Nasser and to Sudanese as Lake Nubia. |
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The last 1200 km of the 6800 km long Nile lie in Egypt north of the first cataract, and for its entire course in Egypt the river receives no perennial tributaries. In ancient times Egypt was divided into Lower and Upper Egypt, with Lower Egypt being the delta region and Upper Egypt being the region from the delta to the first cataract at Aswan. Even though the Nile flows only 170 km through the delta, this contains about twice as much agricultural land (about 22,000 km2) as lies in Upper Egypt (about 12,000 km2). |
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The Nile becomes increasingly important the farther north it flows into Sudan and Egypt. This is because it brings water to these regions which lie in Earth's greatest and most desolate desert, the Sahara. Without the blessing of Nile water, Egypt today would be as empty as the rest of the Sahara, and civilization would have had to begin elsewhere. Because of the Nile, Egypt was one of the wonders of ancient times, providing inspiration essential for the development of societies in ancient Greece and Israel which in turn provided the bases for the philosophical, scientific and religious outlooks that define Western Civilization. The continued blessings of the Nile allows Egypt to continue today as one of the largest and most powerful nations of Africa and the Middle East. There can be little doubt that if the Nile did not flow through Egypt, the human endeavor we call civilization would be a very different thing than it is today, if it existed at all. In the same way that the Nile valley and delta define Egypt, changes in the nature of the river define Egypt's natural frontier. North of Aswan, the river has a gentle gradient, dropping 1m in every 13 km. It can be navigated by boats powered by sails or oars, and it is flanked by a floodplain that widens progressively to the north, then fans out to make the delta. The scale of agriculture increases as the area of cultivatable land increases northward, and this allows for larger populations to the north. Aswan marks the first cataract, significant because this was a great natural obstruction to travel upstream by sailboats or those powered by oars. The cataract itself is an obstruction of the river caused by a series of rocky rapids and small islands. Upstream for hundreds of miles from Aswan the floodplain was narrow and could not be cultivated to support a great population. In the Old Testament (Ezekiel 29:10) it is stated that Egypt ends and Ethiopia begins at Syene, the ancient name for Aswan. It was only at the beginning of New Kingdom times about 1200 B.C.) that Egyptian armies ventured very far south of the first cataract. More recently the construction of the High Dam at Aswan emphasizes the fact that Egyptians have always felt that their country ended and Africa began at the first cataract. The 350km long stretch of the Nile from the Sudan border to 7km upstream from Aswan once flowed through a narrow valley bordered by sandstone cliffs but is now covered by the waters of the artificial lake known to Egyptians as Lake Nasser and to Sudanese as Lake Nubia. The last 1200 km of the 6800 km long Nile lie in Egypt north of the first cataract, and for its entire course in Egypt the river receives no perennial tributaries. In ancient times Egypt was divided into Lower and Upper Egypt, with Lower Egypt being the delta region and Upper Egypt being the region from the delta to the first cataract at Aswan. Even though the Nile flows only 170 km through the delta, this contains about twice as much agricultural land (about 22,000 km2) as lies in Upper Egypt (about 12,000 km2). Following the Nile north from Aswan, its valley is narrow immediately north of Aswan and is surrounded by sandstone cliffs until near Kom Ombo where a broad flat plain appears. The valley narrows again at Gebel Silsila gorge, known in ancient times as "Kheny" which has been translated as "The place where you have to row." Silsila seems to have been a waterfall until the Holocene, about 10,000 years ago, and was probably responsible for impounding water and sediments to form the broad plain upstream around Kom Ombo. Quarries in the sandstone cliffs were exploited from the 18th Dynasty until Greco-Roman times. The river flows through a narrow valley for another 30 km and then its valley begins the broadening that will continue all the way to the delta. The river is bounded between steep cliffs even as the floodplain broadens. Back of the flood plains on either side are precipitous cliffs rising up to 300m to the brink of the dry, barren, lifeless plateau which extends away to the east and west. Near Esna, about 160 km downstream from Aswan ,the sandstone of the bounding cliffs is replaced by limestone, and limestone makes up the bounding cliffs all the way to the delta. At Qena, about 120 km downstream from Esna, the Nile swerves east and the valley broadens significantly. Limestone cliffs rise to heights of 300m or more on either side of the valley. It is in these limestone cliffs that the pharonic tombs in the "Valley of the Kings", west of Luxor near the south end of the Qena bend, were built. (For a really neat perspective of the Nile Valley near Luxor, click here . Near Assiut, about 260km downstream from Qena, the cliffs on the western side become much lower than those on the eastern side and continue so for about 400km to Cairo. From Qena to the delta the river stays on the east side of the valley. Nearly 90% of the cultivatable land in Upper Egypt lies on the west bank of the Nile. |
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The Nile in Egypt extends for 1200 km between Aswan and the Mediterranean Sea, and consists of two parts, the Nile Valley and the delta. The Nile Valley consists of the broad floodplain which flows between steep limestone or sandstone hills. The floodplain and the width of the valley floor widen northward until it opens up into the delta, just north of Cairo. The term "delta" was was coined to descibe the region where the Nile flowed into the Mediterranean. The ancient greeks were impressed by the triangular outline of the region around the Nile's mouth and how similar this shape was to the 4th letter of the Greek alphabet (D). The Nile splits into two branches at the south end of the delta, the western or Rosetta branch (where the famous "Rosetta Stone" - the key to deciphering hieroglyphics - was discovered by Napoleon's troops in 1798) and the eastern or Damietta branch. Up to the time that the Aswan High Dam was built, the delta continued to expand northwards into the Mediterranean Sea as Nile floods deposited their annual sediment loads. These sediments are now filling Lake Nasser, with the result that the sediment-starved delta is slowly sinking and its shoreline is retreating. |
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In 1898 a dam was built across the Nile just south of Aswan, for the purpose of saving some of the Nile flood waters and releasing it during times of low flow, later in the year. Since completion in 1964 of the much larger structure to the south, the older structure is known as the Aswan Low Dam and the newer structure the Aswan High Dam. The Aswan High Dam impounds the largest artificial lake in Africa, which extends for about 270 km south of Aswan. The reservoir is known as Lake Nasser in Egypt and Lake Nubia in Sudan and was designed to provide Egypt a reliable source of water for irrigation and hydroelectric power. Water that used to be lost to the sea is now saved. This store of water saved Egypt many problems when drought affected the Nile headwaters during the early 1980's. The increased reliability of water due to Lake Nasser/Nubia has allowed Egypt to irrigate desert areas and so increase her agricultural acreage, something that is critical for a country with a very high birthrate and little agricultural land. One of the most ambitious new projects is the 'New Valley' project, where some water from Lake Nasser will be diverted west into the desert to irrigate vast tracts of desert; this project has only just gotten underway. In spite of these great benefits to Egypt, the Aswan High Dam has been a mixed blessing. Much water is lost by evaporation; it is no surprise that rainfall rarely falls in the Sahara, while evaporation is about 3m annually! The tremendous surface area of the lake ensures that a large percentage of the lake's water is lost each year. The reservoir also serves to trap the sediment that used to nourish the floodplains of the Nile valley. The longevity of Egyptian civilization reflects more than anything else the power of her soil to grow crops. The ability of this soil to produce year after year, century after century, millenium after millenium, is unparalleled in human history. Where other civilizations withered and died as their soils were exhausted - the many civilizations of mesopotamia are a good example - the soil of Egypt was never exhausted. This was because the annual veneer of new soil deposited from the flood, along with the leaching of salts from the soil by the inundation itself naturally renewed the soil. Now that the Nile no longer floods downstream of Aswan, artificial fertilizers must be applied and soil salinization is an increasingly serious problem. Losing the annual addition of sediment has also effected the Nile Delta, with seawater encroaching from the north as the delta continues to slowly sink. Health problems such as the increase in waterborne diseases such as bilharzia have also increased since the dam was constructed. And let us not forget that many ancient temples and monuments are drowned by the lake. |
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