GCSE Geography Year 10
UNIT 2 WATER, LANDFORMS & PEOPLE.
Case Study: Over coming water shortages and controlling floods. The River Nile and the Aswan high dam, Egypt.
Introduction: There are many world examples of where an attempt to solve one human problem can create new environmental ones. The building of the Aswan Dam on the River Nile in Egypt is one such example.
Facts about the Nile: • The Nile is the world’s longest river. • It flows 6,690 km (4,160 miles) from its source on the equator to its mouth in the Mediterranean Sea. • The river basin of the Nile covers one-tenth of all Africa. • During its 1,520 km (950 mile) journey through Egypt it has no tributaries and hardly ever gets any rain.
Egypt, the gift of the Nile: Nile supported agricultural population for thousands of years. River supplied Egypt’s water needs. Annual floods deposited nutrient-rich silt next to river and in delta. Irrigation made farming possible in an otherwise desert area.
Water for irrigation was obtained by two methods: • Each Autumn, annual flood water was allowed to cover the land, where it remained trapped behind small bunds until it deposited its silt. 2. During the rest of the year when river levels were low, water was lifted one or two metres by a shaduf (sakia) wheel or Archimedes screw.
The Shaduf is a long pole. At one end is a bucket which is dipped into the river, and at the other end is a heavyweight. The weight makes it easier to swing the full bucket round to the irrigation channel. Only the land next to the Nile had a reliable, regular supply of water. Land further away from the river needed to be irrigated. Irrigation is the artificial watering of the land. One old method is shown below
Early river management: • Since the time of the Pharaohs, the Egyptians wanted to control the Nile so that its level would remain constant throughout the year. • Barrages designed to store water did not meet the needs of the country’s rapidly growing population and increasing demand for food. • The problem was how to increase the area of cultivated land and, at the same time, produce electricity.
Aswan High Dam fact file: • The dam and associated hydro-electric power station, opened in 1971. • It took 11 years to construct. • Lake Nasser, which formed behind the dam, is 550 km in length. • The area of Lake Nasser is 6000 km 2. • The total capacity of the lake is 162, 000 million litres.
A multipurpose scheme: It was built: • To stop, by storing water in Lake Nasser, serious flooding in the Lower Nile valley and, by releasing it throughout the year, to maintain a constant river level. • To provide water all the year round for domestic, agricultural and industrial use. • To increase the area of cultivation. • To provide hydro-electric power.
Was the dam a success? While the scheme has indeed brought many benefits to Egypt (mainly economic and social), it has also created many problems (often environmental and health), some of which were unforeseen.