S6 UNIT 14
Overview
Key Unit Competence: By the end of the Unit, I should be able to evaluate the impact of multi-purpose river projects on sustainable development of different countries in the world.
WORLD MULTIPURPOSE RIVER PROJECTS
14.1. Definition, aim, objectives and importance of multipurpose river Projects
This refers to projects that are built on various rivers and are used for different purposes such as providing power, eliminating floods, providing water for agriculture, domestic and industrial use.
Aims of multipurpose river projects: The aims of the multipurpose river projects are to increase the economic independence through the sustainable development of various economic sectors, the national wealth and the standards of living of inhabitants.
Objectives of multipurpose river development:
- To control flood.
- To provide water for irrigation, diversify agricultural production.
- To check soil erosion.
- To provide water for drinking and domestic purposes.
- To generate electricity for industries, villages and cities.
- To provide inland navigation.
- To encourage tourism and recreation.
- To preserve wildlife.
- To develop fisheries.
- To create employment opportunities.
- To promote industrialization and urbanization.
- Diversify the economy.
- Creation of settlements for the landless/surplus population.
Hydro-electric power plant (HEP): an hydro-electric power plant is constructed to generate hydro-electricity for industries and homes. As represented on the figure below, a hydro-electric power plant arrangement consists of basic sections such as dam, reservoir, penstock, control gates, turbines, power house which include generator and transformer and power lines.
These basic sections are briefly described in the following:
Dam: A barrier constructed across a river to hold back water and raise its level, forming a reservoir used to generate electricity or for domestic, irrigation or industrial water supply. Some dams are built also to preventing the flow of water or loose solid materials (such as soil or snow).
Reservoir: The part of river where water will be stored is called Reservoir.
Penstock: Penstocks are generally made of reinforced concrete or steel to transport water from reservoir to turbine with less friction losses.
Control Gate: Also called crane is used to control over the water travelling in penstock.
Turbines: Water turbines are used to convert the energy of falling water into mechanical energy and enable generators to produce electrical energy from rotating shaft of turbine.
Power House: At the power house generated power from generator will be stepped up and supplied to transmission power lines.
Power lines: wires connected to the generators that carry electricity to homes, industries and mines.
14.1.2. Importance of multipurpose river projects for sustainable development
The benefits of river dam projects for the sustainable development of countries include:
- Provision of cheap and reliable hydro-electric power: Most river dam projects in Africa are used to generate hydro-electric power for both domestic and industrial purposes.
- Provision of water: The dams provide water for domestic, industrial and irrigation uses for local inhabitants residing nearby. The water stored behind dams is irrigation reservoir which helps in the growing of crops, especially during the dry season. This has reduced farmers’ dependence on climate. Irrigation farming can be carried out to increase food supply.
- River water is renewable source of energy: In contrast of other sources of energy which are non-renewable because they are exhausted with time as they are exploited (e.g. wood, coal, petroleum), multipurpose river projects are mainly built on river water which is long lasting and one of renewable source of energy.
- Development of tourism: Some multipurpose river projects can be of tourist interests, thus earning foreign exchange, because river dam projects are associated with features like impressive architectural designs, waterfalls, dams and lakes which may be fascinating to the people that come to visit the places.
- Generation of government revenue: This is through taxation of workers’ incomes and earning of electricity and water boards.
- Employment opportunities: River dam projects create employment opportunities for several people, especially those engaged in the production of hydro-electric power and supply of water for domestic, industrial and irrigated agriculture developed in the area. Provided employment raises people’s standards of living.
- Industrial development: The projects have stimulated the development of industries as there is ample power that is generated. This enabled the boost of textile, brewing, sugar processing and steel rolling industries.
- Development of infrastructure: The projects have opened water transport routes or shipping routes (river navigation). Many other infrastructures such as development of towns, schools and hospital facilities among others have developed within the river valley.
- Promotion of international relations: There have been joint ventures in the development of river projects that have created co-operation among nations.
- Flood control: Dams are used to control flooding in flood-prone areas by regulating the flow of water downstream.
- Reduction of importation: There is reduction on costs incurred on the importation of fuel, manufactured products and foodstuffs since these are now produced locally.
14.2. Problems affecting Multipurpose River Projects
- Change in river regime
- Inadequate funds
- Inadequate skills and technology
- Deforestation
- These projects have led to displacement of people where dams are built.
- Construction of dams caused ecological problems like blocking the migration of fish
- Siltation of dams
- Excessive evaporation which leads to the change of climate conditions
14.3. Solutions to the problems affecting Multipurpose River Projects
- Establishment of the project based on accurate environmental conditions such as the characteristics of river regime and seasonal fluctuations, to avoid situation where the project collapses soon after its establishment.
- Training people to do the maintenance of the machinery and infrastructures generated by the project. The lack of required home-grown skilled personnel can be addressed if governments plan early enough and invest in the area of human resource development, to improve their human resources capacity and thus reduce dependence on foreign expatriates who are always quite expensive to hire.
- Continuous monitoring and evaluation of projects and taking corrective measures are needed.
- Continued partnership and cooperation with donors and funding agencies to obtain soft or long-term loans with which to finance the project activities.
- Fight and contain the spread of Bilharzia/Schistomiasis over irrigated project areas.
- Resettle the landless due to the drawning of agricultural land by the manmade lake resulting from dam construction.
In order to maintain the viability of the projects, some of activities to undertake include:
- Removing in the waters the invasive species which are dangerous to aquatic lives.
- Allow sufficient time and money for extensive public participation to ensure that plans are optimal; that all sections of affected society are considered and; that local institutions are in place to sustain irrigated agriculture, particularly in respect of land and water rights;
- Afforestation: The increase of number of trees and vegetation protects the water catchment areas of the rivers feeding the dams. This reduces the fluvial erosion and other types of erosion which could damage the dams;
- Provide short-term support and/or skills for an alternative livelihood if irrigation removes existing livelihood.
14.4. Case Studies
14.4.1. The Tennessee Valley Authority (USA)
The Tennessee basin in USA was often devastated by floods and its economy depressed because the pioneer settlers and their descendants farmed using inappropriate traditional methods till the region became poverty-stricken. The soils were eroded, hill slopes were treeless, rivers which were filled with silt eroded from the surrounding hills became uncontrollable, causing huge floods on extensive parts of the region and many damages to lives and properties. The Tennessee Valley became one of the poorest parts of USA in terms of economic wellbeing.
In 1933, the president Franklin Roosevelt signed the act to establish the Tennessee Valley Authority (TVA). It is found in USA. It was constructed in 1993 to provide navigation, control floods and for purpose of electricity generation. The TVA was formed to solve the problems in several states such as: Tennessee, Kentucky, Virginia, North Carolina, Georgia, Alabama and Mississippi. It was undertaken in Tennessee valley area to revive one of the poorest and badly eroded parts of USA.
i. Aims of The Tennessee Valley Authority
The Tennessee Valley Authority (TVA) is a corporation formed for large-scale rehabilitation of a vast region which includes parts of seven adjoining states of Tennessee, Kentucky, Virginia, North Carolina, Alabama, Georgia and Mississippi, in the United States of America (USA). The Tennessee Valley Region is drained by the Tennessee River and River Timberland, both tributaries of the Ohio River which is a tributary of Mississippi River. The drained area is about 106,000 km². Due to persistent flooding and soil erosion which marked the Tennessee basin for centuries
ii. Problems faced by the region before the creation of TVA
- There were flood on river Tennessee and its tributary which caused massive destruction of farmlands, loss of property and human lives.
- Poverty had become a major challenge due to lack of employment opportunities and means of livelihood.
- Soil erosion especially on the hilly slope of the Appalachian Mountains had become a threat to the farmers and entire region. Famine had become a serious problem.
- Diseases like malaria and bilharzia due to floods had become common.
- There was rampant unemployment due to lack of industries within the region.
- There was a problem of poor transport system because Tennessee river and its tributaries were not navigable.
- High government cost
iii. Strategies taken by the USA central government to solve the problems
Strategies taken to solve the problems in Tennessee region were sequenced in various steps:
Step 1: Assignments tasked to the Tennessee Valley Authority
The following tasks were assigned to Tennessee Valley Authority when it was created:
- Building dams to control flooding of River Tennessee and its tributaries and later generate hydro-electric power. The generated electricity would be exported to other neighboring states thus reaping revenue for the state.
- Controlling severe soil erosion by putting in place sustainable conservation measures, and mechanisms for reclaiming badly eroded lands and flooded swamps in the area.
- Promotion of forestry through afforestation programs. These programs aimed to reduce flooding and soil erosion in the area.
- Improvement of the transport facilities such as roads, railways and water transport whose construction and maintenance were hindered by floods.
- Promotion of the industrial development to increase alternative employment opportunities to the people in the area, in the agriculture sector and industrial sector.
- Teaching inhabitants better farming methods to improve sustainably agriculture in the region.
- Providing enough and sustainable housing to accommodate the rapidly growing population.
- Conserving wildlife in the area.
- Controlling the spread of diseases such as malaria and Bilharzia that resulted from floods.
Step 2: Concrete actions taken to control soil erosion
The following are concrete conservation measures taken by TVA to control soil erosion:
- Training of farmers: Experts were hired from outside the local area especially from other agriculturally advanced regions of USA like California and Southern USA to educate local farmers on how to improve their farming methods;
- Creation of demonstration farms: aimed at giving advice to farmers on modern and better farming methods such as mixed farming and crop rotation;
- Re-afforestation programs: These were undertaken to plant young trees on ridges and hills. Their roots would bind the soil particles together and absorb excess water which was previously running off;
- Filling the Gullies: gullies were covered with brushwood to cover and trap soils and stones and eventually fill up the gullies;
- Terracing: this involved the cutting of a series of wide steps and construction of embankments on hilly slopes to reduce gradient and surface runoff;
- Introduction of modern farming methods: farms were mechanized in order to increase the production. The use of fertilizers and manure to maintain soil fertility was also applied.
Step 3: Construction of Dams and results
- Several dams were constructed: Nine dams were constructed on the main Tennessee River and 23 on its tributaries. The major ones along the Tennessee River include Noris, Cherokee, Fontana, Chickamauga, Willson, Pickwick, Fort Loundon, Douglas, Kentucky, Guntersville, Hirwassee and Walts bar. All the dams can control floods, storing water, assisting navigation and generating hydro-electricity.
- The huge reservoirs created by the dams hold back enormous quantities of water: This reduced greatly the flood heights, and since then this water is released for irrigation purpose or holds water for navigation.
- Elimination of swamps: The management of swamps resulted in a complete elimination of malaria and bilharzia
- Development of tourism: Natural parks and man-made lakes were created. Camping, canoeing and hunting have been promoted. The scenic beauty around dam recreation facilities at wildlife reservations attract more tourists and increase foreign exchange.
- Supply of Electricity to industries: The TVA also directs the storage and release of water and generation of power at four dams owned by the Aluminum Company of America (ALCOA).
Step 4: Construction of important infrastructures and industries The major infrastructures and industries constructed include:
- Electric Power Station and urban development: Constructed power stations stimulated the growth of urban centres, for example, Memphis and Birmingham
- in Alabama State, Atlanta in Georgia and many others across the region. By 1953, 80% of homes in the region were electrified, compared with 3% at the beginning of the project in 1933. Today the full-scale rural electrification has been a great achievement for the TVA.
- Transport Infrastructures: Roads, air and railway transport networks were constructed in the region. Navigation on created dams on Tennessee and transportation of freights and passengers over a distance of 1.050 km are known to be among the most efficient worldwide.
- Educational and research institutions: Various Institutions of learning such as Universities, Colleges and Schools were constructed in Tennessee Region. All research centres were established with linkage to universities and colleges.
- Industrial centres: Industries were constructed to generate employment opportunities to the people. Major industries include Aluminum manufacturing, fertilizers industry like phosphates, paper mills, chemicals, pharmaceuticals, automobiles and food processing plants.
- Health centres and hospitals: Several health centres and hospitals were constructed to improve the health of states within the Tennessee catchment area. These are able to serve not only the seven states of the region, but the international community as well.
Benefits of TVA for sustainable development of the region
- The control of floods and soil erosion has been successfully and sustainably mastered.
- Cheap hydro-electric power was availed: This attracted diversified industries that offered employment within the Tennessee valley.
- Diversified food products: Milled grains, baked foods, confectioneries and beverages and many others are produced in the region.
- Local farmers joined the established demonstration farms: Farmers were trained on better farming methods to control soil erosion and increase crop yields.
- Diversified and improved transport networks: This encouraged significantly the local and international commerce.
- Many and diversified industries in the region process ores and other raw materials: Raw materials that were formerly processed in the North East of USA are now processed in the Tennessee region.
- Tourism was greatly promoted: The region covered by TVA earns the government of USA foreign exchange as a tourist attraction destination;
- The production of motor vehicles, boats and aircraft parts: Constitute Tennessee’s largest industry in terms of contribution to overall TVA’s states economies.
14.4.2. Akasombo Dam – The Volta River Project (Ghana)
i. Location and site of Akasombo Dam
The construction of the Akasombo Dam was the first Ghanaian project undertaken by the Volta River Authority (VRA) in 1960. The dam is located on River Volta near the Akasombo town in southern Ghana. The site has been chosen because it was where the river valley was narrowest and surrounded by a rock strong enough to hold the dam
Aims and objectives of the project
The project aimed at constructing Akasombo Dam and Volta Lake, one of the longest man-made lakes in the world. The dam is 111 m high and 660 m long at the top and 366 m at the bottom. A man-made lake; called Volta Lake, was formed behind the dam covering an area of 8502 sq.km. The Lake extends for 400 km with a shoreline of 7,250 km.
ii. The dam was built with the following objectives:
- To provide cheap electricity to run the smelter: called Volta Aluminum Company (VALCo) located at the new port of Tema and to increase the Ghana’s domestic and industry supplies of power.
- To control and regulate the flows and recurrent flooding of the River Volta.
- To promote agriculture through development of irrigated farming but also to provide a major inland waterway.
- To construct the Lake Volta to enhance fishing and supplement population in animal proteins.
- To create employment opportunities for Ghanaian population to improve the standards of living for the people in the area.
iii. Factors favouring the establishment of the Akasombo river project
- The heavy and well distributed rainfall provides regular and reliable supply of water in Volta basin. This makes the flows more regular and energy produced relatively constant.
- The availability of land. The region around Akasombo is sparsely populated.
- The hard basement rocks provided a firm foundation for construction of the dam.
- The River Volta crosses a narrow gorge located at Akasombo valley in the south eastern part of Ghana where River Volta cuts through Akwapin hill.
- A large market - There is high demand for the power generated for both industrial, especially the Volta Aluminum Company (VALCo) and for domestic use, and high demand for other products from the multipurpose project.
- Foreign investors - the foreign investors especially from USA and Britain provided a support in form of skilled labour.
- The availability of capital to construct the complex to provide power and set up flood controls, from the World Bank and Britain.
- The creation of Volta River Authority (VRA) whose primary task was to manage the development of the Volta basin, which include construction and supervision of the dam, the power station and the power transmission network.
- The government policy to develop a large-scale multipurpose project to promote economic development.
- Importance of Akasombo Dam
- Hydro-electricity production promoted industries, port cities and international co-operation.
- The generation of hydro-electric power (HEP) has significantly reduced the expense of importing petroleum oil for thermal power stations thus saving foreign exchange.
- Cheap electricity is supplied to VALCo smelter.
- Ghana can process much of the bauxite (Aluminum ore) instead of shipping it in raw state which is bulky.
- Akasombo dam allowed the development of numerous industries at Tema, Accra, Tokoradi and Kumasi cities. Industrial development has enabled Ghana to become less dependent on import of some food stuff and to process locally some of agriculture products, e.g. cocoa.
- It has enabled the development of ports and urban centres. For instance, Tema is an industrial city home of the Aluminum smelter.
- The dam supplies electricity to Ghana’s neighbors such as Togo, Benin and Ivory Coast. This has strengthened economic co-operation between Ghana and her neighbours.
- Development of transport, fishing and tourism.
- Irrigation has promoted agriculture. New farming activities developed along the shorelines of Lake Volta as it became valuable resource for irrigation. It is a potential source for irrigation which enabled Ghana to grow various crops among others such as rice, sugarcane, maize and vegetables.
- Farming has greatly improved and diversified. The Akasombo Dam and Lake Volta are great tourist attractions which bring in foreign exchange.
- The project has generated employment opportunities to many people, for instance, people involved in the distribution of electricity in the cities of Accra, Tema, Tokoradi and others.
- The project has raised the people’s standards of living and has helped in the diversification of the economy from being predominantly agricultural to industrial, mining, fishing and tourism, hence multipurpose development.
- Problems associated with the Akasombo dam project
- The dam flooded traditional farm land and about 80,000 people were displaced by the rising water of lake Volta.
- There is high cost of resettlement and disruption of families
- Volta Aluminium Company needed a lot of power for smelting aluminium and it consumed more than half of the power produced, so several areas/ people were deprived of the use of electricity.
- The development of industries like aluminium smelter and oil refining at Tema led to environment pollution.
- Lake Volta become habitat for disease vectors like water snails and mosquitoes, which are found in stagnant water and that led to spread of bilhazia and malaria respectively.
- During the period of drought, there was reduction in lake levels which reduced the power output.
- Due to the development of HEP, other power sources lost market, which discourages their producers.
- Silting of lake Volta.
Solution to the problems
- Public education and provision of sanitary facilities are used to maximize avoidance of the risk of bilharzias infection in the vulnerable group. Drug are also used for treating infected members of the community.
- Water weeds are controlled
- Artificial shrimp farms have been established in the lower Volta using simple and inexpensive methods, hence, fighting poverty.
- The 80,000 people who were displaced were settled into 52 resettlement villages.
14.4.3. Aswan High Dam (Egypt)
It is located on the River Nile in Egypt near the city of Aswan. The construction of the dam led to the creation of a man-made lake known as Lake Nasser. The reservoir was named after Abdel Nasser, the leader of Egypt at the time. It has the capacity of 2100 MW. The construction of the dam started in 1960 and was completed in 1970. The dam is about 3830 metres long and 111 metres high. Its base is 980 metres wide.
i. Aims and objectives of the project
The project to construct Aswan High Dam was conceived with aim to develop sustainably the country in various economic sectors
The major objectives of the project are:
- To prevent recurrent flooding which affects the Nile valley during the rainy season, mostly in August and September.
- To control and provide a regular flow of water for irrigation, during both the dry and rainy seasons.
- To enable the country to grow enough food to feed the growing population.
- To increase the amount of irrigated land.
- To generate Hydro-electricity Power for both domestic and industrial purposes.
- To create a man-made lake (reservoir) where a fishing industry could be established.
ii. Factors favouring the construction of Aswan High Dam
- Strong basement rock: The dam was constructed where a strong basement rock to support heavy dam structures existed. This provided a firm foundation for the dam.
- The channel was narrowed where the dam was constructed. This made the construction cheaper and easier.
- Presence of large capital invested: The construction and the maintenance of the dam were made possible by funds provided by the Soviet Union and Egypt goverments.
- Availability of skilled labour: Russian experts and egyptians semi-skilled labour were hired to construct the project.
- Advanced technology involved in the general work of dam construction which included strong turbines which produce high power voltage.
iii. Importance of Aswan High Dam for the sustainable development of the region
- This became a source of government revenues,
- creation of employment opportunities for many people.
- Flood control: The dam enabled the control of floods and regulated the flow of the River in the Nile valley. People’s lives and properties are safe in the Nile valley. This saved money which was formerly spent on displaced people. The reservoir created provides water in times of droughts.
- Production of Hydro-electric power (HEP): Aswan High Dam has an output of about 2100 MW. The production of (H.E.P). has led to the development of diversified industries in the region, such as iron and steel, textiles; mining industries especially oil drilling (Petro-chemical) and sugar refining especially in Cairo and the free zone area of the Nile delta. The establishment of industry has created employment opportunities to the majority of local Egyptians.
- Provision of power for domestic purpose: There has been a program of rural electrification, especially along the Nile and in rural villages because of the presence of the Aswan High Dam.
- Improvement of agriculture sector: Irrigated land area of Egypt has increased by 25 percent since Aswan High Dam is established. Farmers can now grow several crops in the year, such as maize, wheat, barley vegetables and others.
- The water in the region is supplied on regular basis: L. Nasser holds with 80 % of its water going to Egypt and 20 % to Sudan. The water stored is used for irrigation.
- Promotion of fishing: Lake L. Nasser has promoted the fishing industry,
- Promotion of tourism: The Aswan High Dam and Lake Nasser are tourist attractions. This enables to earn foreign exchange.
- Reduction of costs to import fuel: The construction of the dam has resulted into a significant reduction of costs incurred on the importation of fuel petroleum products.
iv. Problems associated with the construction of the Aswan High Dam
- There was displacement of people and their livestock: 42,000 people who used to live in the region that is now covered by Lake Nasser were evacuated 1,300 km by rail across Nubian Desert to Khasm El Gibra.
- A lot of cost for resettling displaced people: Much fund was involved to relocate people since they were given double their foremen hectares of land and the irrigation and electric power had to be provided from the new dam.
- Pollution of water, soil and air: this was due to the establishment of industries in the area.
- Increase of diseases like bilharzias and malaria: The outbreak of these diseases was caused by stagnant water, this causes great expense to the government economy in treating its people.
- High evaporation of water: It is estimated that 25% of water is lost through evaporation because of high temperatures. The high evaporation rates lead to increased saline deposits in the soil which are associated with decreased yield.
v. Solutions to the problems associated with Aswan High Dam
Some solutions have been put forwards to solve problems caused by the Aswan High Dam.
- Regular dredging is carried out to remove waste matter which affect the drainage of the new valleys.
- Treatment of waste (recycling) is performed before their disposal. Some environmental laws have been set to regulate dumping in the river.
- Construction of levees to control overflow of water that resulted in floods.
- Use of ferry and steamers to ease the communication around Lake Nasser.
- Spraying to control diseases such as Bilharzia spread by snails from the stagnant water which gives a breeding ground for them.
- There is a legislation against brick making along the river bank.
- Farmers are sensitized to the use of organic manure as opposed to inorganic fertilizers to reduce salinity and soil pollution.
- Sensitization of population for new settlement plans: There has been a general sensitization for new settlement along the river bank against dumping of garbage in the river which is partly responsible for making the river burst its banks.
14.4.4. Huang He River Project (China)
i. Location of Huang Ho River
Huang He called the Yellow River (formerly known as the Hwang Ho), is located in China. The river originates from the Northern part of mount Bayan Ha of Tibet plateau in Qinghai province and runs Eastwards, a distance of 5,464 km to empty in the Bo-hai Sea at Shantong.
The river flows through 9 provinces namely Qinghai, Sachuan, Ganso, Ningxia, Inner Mangolia region, Shanxi, Shaanxi and Shanang.
It covers an area of 750,000 km2. The main tributaries of the Huang Ho in its lower riches include Taohe, Jighe, Welhe, Luohe, Fehhe, Yihe and Qinhe. The Huang Ho River is China’s longest and largest river after the Yangtze River, with over 30 tributaries feeding it.
ii. Problems faced in Huang Ho Basin
The following are some of challenges faced in the Huang He basin:
- Several foods along the Huang He River
- Severe soil erosion and large silt load
- Irregular flow and change of river course
- The river faces a threat of drying up
- High population growth rate
- Problem of pollution
iii. Aims and objectives of Huang Ho Basin Development project
In 1950 the government of China created a multipurpose project called “Huang Ho Basin Development”. The major aim was to control devastating floods and to sustainably develop areas around the yellow river.
The major objectives of the project are meant:
- To reduce the risks of flood to lives and properties;
- To produce energy and increase the discharge during dry periods; • To retain silt and store water for irrigation;
- To provide water for home consumption and industries.
iv. Importance of the project
- Several dams were built: over 40 dams were built along Huang He and its tributaries to regulate the flows of water and to produce hydro-electric energy. Activities of construction were sequenced between 1960s and 2010s. The most documented hydroelectric power stations of the project include Sanmenxia, Xialangdi, Sanshengong, Qintong Gorge, Luijiiaxia, Lijlaxia Dam, Yuanguoxia, Lianqio, Bapanxia, Da George Dam, Li Geong Dam, Wanjiazhi Dam and Laxiwa Dam.
- Development of cities and settlement centres: Several cities were created and greatly expended in the Huang He basin (see the map below). More than 400 million people have settlements in the Huang-Ho river basin. This was possible because of the multi-functional projects focusing on the development of traffic (roads, navigation on Huang-ho River year round), ecology, economic and flood prevention for the cities along the river that attract people to settle in the area for employment opportunities.
- Creation of reservoirs: Some dams were created with the main purpose of storing water. For instance Longyang gorge, Liujia Dam, Xialangdi Dam
- Floods control: The regulation of rivers’ flow has virtually eliminated floods that regularly submerged the northern china’s plain.
- Food production: The crops grown are rice, wheat, maize, soyabeans, potatoes, sweet potatoes and cereals. This uspports a large population living along the river basin.
- Remarkable expansion of irrigation: Irrigation of the dry areas of the northern part of China was made possible with the help of the Huang-Ho River. irrigated area increased from 0,8 million hectares in 1950 to 7.5 million hectares in 2000.
- Tourist attraction: Many tourist centres along Huang He promote the tourism industry. The touristic features include the Hukou falls in Shaanxi, the caves, stone statues and the Huang-Ho river dams, among others. Tourism is a major foreign exchange earner in China.
- Industrial development is facilitated by the Huang-Ho River. A number of industries have developed in the region, such as petrochemical factories and mining industries. The river provides significant amounts of water to industries to cool the machines.
v. Challenges faced the project
- Increased rate of water demand and use resulting from high population growth and regional economic development caused the drying up of the flow of the river.
- Parts of the river especially in mountain area remain frozen in winter season during which water remains frozen, and the water supply from precipitation is limited.
- The Yellow river crosses some arid and semi-arid region. Thus precipitation and water sources are limited.
- The land surface change from slope land to terraces has involved expansion of irrigation activities which affected the regional hydrology and rive flow.
vi. Measures to solve problems related to water shortage
There is a water transfer from the South to the North project to channel through the ground canal from River Yangtze where water sources are relatively rich in the South to the Huang Ho where water resources are limited.
14.4.4. Orange River scheme – South Africa
Orange River project was developed by South Africa during the apartheid era. The 2,200 km long River has its source from Drankensberg mountain ranges in Lesotho and ends in the Atlantic Ocean. Several dams have been built along the River Orange and its tributaries.
The dams built include:Welbedacht Dam, Gariep dam, Vanderkloof dam, Torquay dam, …
The major objectives of the Orange River project were:
- To create reservoir for storing water for irrigation, to promote agricultural production in the Orange river basin.
- To control floods of River Orange.
- To generate hydro-electric power.
- To supply water in arid areas of Eastern Cape such as the Great Fish and Sundays River valleys.
- Contributions of Orange River project
- The Orange River project contributed much to the development of south Africa.
- The project supplies water to the cities like Bloemfontein, Kimberly, Port Elizabeth and small towns.
- It has created an increase in population in the Orange River basin by attracting farm labor of 160,000 people.
- River Orange which used to flood the lower areas destroying property and life has been controlled. After dam construction, the floods have become less frequent and less destructive.
- The project created employment opportunities to a number of people.
- Irrigation farming has flourished in dry areas.
- Industries have been established. Gariep dam generates 360 MW while Vanderkloof dam generates 240 MW of HEP.
- These boosted the development in the mining industry and manufacturing industries.
- Dams constructed in the region led to the development of towns by supplying electricity which runs different activities.
- Fishing is carried out in manmade lake (reservoirs) created by the scheme.
- Dams have promoted tourism; the county gets foreign exchange