You already know that three-fourth of the               Water: Some facts and figuresearth’s surface is covered with water...
• By 2025, it is predicted that large parts of      associate it with regions having low rainfall       India will join co...
requirements but have further aggravated the  According to Falken Mark, a Swedish expert,     problem. If you look into th...
MULTI-PURPOSE RIVER PROJECTS AND                             What are dams and how do they help usINTEGRATED WATER RESOURC...
Find out more about any one traditional              Narmada Bachao Andolan or Save  method of building dams and irrigatio...
India: Major Rivers and Dams28   CONTEMPORARY INDIA – II
triggered floods due to sedimentation in the                                                       reservoir. Moreover, th...
purpose projects, water harvesting systemwas a viable alternative, both socio-economically and environmentally. In ancient...
rainfall in the world, yet the state capital                                                         Shillong faces acute ...
BAMBOO DRIP IRRIGATION SYSTEM     In Meghalaya, a 200-year-old system of tapping stream     and spring wate by using bambo...
1. Collect information on how industries are polluting our water resources.     2. Enact with your classmates a scene of w...
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Water Resources

  1. 1. You already know that three-fourth of the Water: Some facts and figuresearth’s surface is covered with water, but only • 96.5 per cent of the total volume of world’sa small proportion of it accounts for freshwater water is estimated to exist as oceans andthat can be put to use. This freshwater is mainly only 2.5 per cent as freshwater. Nearlyobtained from surface run off and ground water 70 per cent of this freshwater occurs asthat is continually being renewed and ice sheets and glaciers in Antarctica,recharged through the hydrological cycle. All Greenland and the mountainous regionswater moves within the hydrological cycle of the world, while a little less than 30ensuring that water is a renewable resource. per cent is stored as groundwater in the You might wonder that if three-fourth of world’s aquifers.the world is covered with water and water is a • India receives nearly 4 per cent of therenewable resource, then how is it that global precipitation and ranks 133 in thecountries and regions around the globe suffer world in terms of water availability perfrom water scarcity? Why is it predicted that person per 2025, nearly two billion people will live in • The total renewable water resources of Indiaabsolute water scarcity? are estimated at 1,897 sq km per annum.
  2. 2. • By 2025, it is predicted that large parts of associate it with regions having low rainfall India will join countries or regions having or those that are drought pr one. We absolute water scarcity. instantaneously visualise the deserts of Source: The UN World Water Development Rajasthan and women balancing many Report, 2003 ‘matkas’ (earthen pots) used for collecting and storing water and travelling long distances to get water. True, the availability of waterWATER SCARCITY AND THE NEED FOR WATER resources varies over space and time, mainlyCONSERVATION AND MANAGEMENT due to the variations in seasonal and annualGiven the abundance and renewability of precipitation, but water scarcity in most caseswater, it is difficult to imagine that we may is caused by over- exploitation, excessive usesuffer from water scarcity. The moment we and unequal access to water among differentspeak of water shortages, we immediately social groups. Water, Water Everywhere, Not a Drop to Drink: After a heavy downpour, a boy collects drinking water in Kolkata. Life in the city and its adjacent districts was paralysed as incessant overnight rain, meaning a record 180 mm, flooded vast area and disruted traffic. A Kashmiri earthquake survivor carries water in the snow in a devastated village. Fig. 3.1: Water Scarcity24 CONTEMPORARY INDIA – II
  3. 3. requirements but have further aggravated the According to Falken Mark, a Swedish expert, problem. If you look into the housing water stress occurs when water availability societies or colonies in the cities, you would is less than 1,000 cubic metre per person find that most of these have their own per day. groundwater pumping devices to meet their water needs. Not surprisingly, we find that fragile water resources are being over - Where is then water scarcity likely to exploited and have caused their depletion inoccur? As you have read in the hydrological several of these cities.cycle, freshwater can be obtained directly So far we have focused on the quantitativefrom precipitation, surface run off and aspects of water scarcity. Now, let us considergroundwater. another situation where water is sufficiently Is it possible that an area or region may available to meet the needs of the people,have ample water resources but is still facing but, the area still suffers from water scarcity.water scarcity? Many of our cities are such This scarcity may be due to bad quality ofexamples. Thus, water scarcity may be an water. Lately, there has been a growingoutcome of large and growing population and concern that even if there is ample water toconsequent greater demands for water, and meet the needs of the people, much of it mayunequal access to it. A large population means be polluted by domestic and industrialmore water not only for domestic use but also wastes, chemicals, pesticides and fertilisersto produce more food. Hence, to facilitate used in agriculture, thus, making ithigher food-grain production, water resources hazardous for human use.are being over-exploited to expand irrigatedareas and dry-season agriculture. You may India’s rivers, especially the smaller ones,have seen in many television advertisements have all turned into toxic streams. And eventhat most farmers have their own wells and the big ones like the Ganga and Yamunatube-wells in their farms for irrigation to are far from being pure. The assault onincrease their produce. But have you ever India’s rivers – from population growth,wondered what this could result in? That it agricultural modernisation, urbanisation andmay lead to falling groundwater levels, industrialisation – is enormous and growingadversely affecting water availability and food by the day….. This entire life standssecurity of the people. threatened. Post-independent India witnessedintensive industrialisation and urbanisation, Source: The Citizens’ Fifth Report, CSE, 1999.creating vast opportunities for us. Today,large industrial houses are as commonplace You may have already realised that theas the industrial units of many MNCs need of the hour is to conserve and manage(Multinational Corporations). The ever - our water resources, to safeguard ourselvesincreasing number of industries has made from health hazards, to ensure food security,matters worse by exerting pressure on continuation of our livelihoods andexisting freshwater resources. Industries, productive activities and also to preventapart from being heavy users of water, also degradation of our natural ecosystems. Overrequire power to run them. Much of this exploitation and mismanagement of waterenergy comes from hydroelectric power. resources will impoverish this resource andToday, in India hydroeclectric power cause ecological crisis that may havecontributes approximately 22 per cent of the profound impact on our electricity pr oduced. Moreover,multiplying urban centres with large anddense populations and urban lifestyles have From your everyday experiences, write a shortnot only added to water and energy proposal on how you can conserve water. WATER RESOURCES 25
  4. 4. MULTI-PURPOSE RIVER PROJECTS AND What are dams and how do they help usINTEGRATED WATER RESOURCES MANAGEMENT in conserving and managing water? Dams were traditionally built to impound rivers andBut, how do we conserve and manage water? rainwater that could be used later to irrigateArchaeological and historical records show that agricultural fields. Today, dams are built notfrom ancient times we have been constructing just for irrigation but for electricity generation,sophisticated hydraulic structures like dams water supply for domestic and industrialbuilt of stone rubble, reservoirs or lakes, uses, flood control, recreation, inlandembankments and canals for irrigation. Not navigation and fish breeding. Hence, dams aresurprisingly, we have continued this tradition now referred to as multi-purpose projectsin modern India by building dams in most of where the many uses of the impounded waterour river basins. are integrated with one another. For example, in the Sutluj-Beas river basin, the Bhakra – Hydraulic Structures in Ancient India Nangal project water is being used both for • In the first century B.C., Sringaverapura hydel power production and irrigation. near Allahabad had sophisticated water Similarly, the Hirakud project in the harvesting system channelling the flood Mahanadi basin integrates conservation of water of the river Ganga. water with flood control. • During the time of Chandragupta Maurya, dams, lakes and irrigation systems were A dam is a barrier across flowing water that extensively built. obstructs, directs or retards the flow, often • Evidences of sophisticated irrigation works creating a reservoir, lake or impoundment. have also been found in Kalinga, (Orissa), “Dam” refers to the reservoir rather than the Nagarjunakonda (Andhra Pradesh), structure. Most dams have a section called a Bennur (Karnataka), Kolhapur spillway or weir over which or through which (Maharashtra), etc. it is intended that water will flow either • In the 11th Century, Bhopal Lake, one of the intermittently or continuously. Dams are largest artificial lakes of its time was built. classified according to structure, intended • In the 14th Century, the tank in Hauz Khas, purpose or height. Based on structure and Delhi was constructed by Iltutmish for the materials used, dams are classified as supplying water to Siri Fort area. timber dams, embankment dams or masonry Source: Dying Wisdom, CSE, 1997. dams, with several subtypes. According to the height, dams can be categorised as large dams and major dams or alternatively as low dams, medium height dams and high dams. Multi-purpose projects, launched after Independence with their integrated water resources management approach, were thought of as the vehicle that would lead the nation to development and progress, overcoming the handicap of its colonial past. Jawaharlal Nehru proudly proclaimed the dams as the ‘temples of modern India’; the reason being that it would integrate development of agriculture and the village economy with rapid industrialisation and Fig. 3.2: Hirakud Dam growth of the urban economy.26 CONTEMPORARY INDIA – II
  5. 5. Find out more about any one traditional Narmada Bachao Andolan or Save method of building dams and irrigation works. Narmada Movement is a Non Governmental Organisation (NGO) that mobilised tribal people, farmers, We have sown the crops in Asar environmentalists and human rights We will bring Bhadu in Bhadra activists against the Sardar Sarovar Dam Floods have swollen the Damodar being built across the Narmada river in Gujarat. It originally focused on the The sailing boats cannot sail environmental issues related to trees that Oh! Damodar, we fall at your feet would be submerged under the dam Reduce the floods a little water. Recently it has re-focused the Bhadu will come a year later aim to enable poor citizens, especially the oustees (displaced people) to get Let the boats sail on your surface full rehabilitation facilities from (This popular Bhadu song in the Damodar valley the government. region narrates the troubles faced by people owing to the flooding of Damodar river known People felt that their suffering would not as the river of sorrow.) be in vain… accepted the trauma of displacement believing in the promise of irrigated fields and plentiful harvests. So, often the survivors of Rihand told us that they In recent years, multi-purpose projects and accepted their sufferings as sacrifice for thelarge dams have come under great scrutiny sake of their nation. But now, after thirty bitterand opposition for a variety of reasons. years of being adrift, their livelihood havingRegulating and damming of rivers affect their even being more precarious, they keepnatural flow causing poor sediment flow and asking: “Are we the only ones chosen toexcessive sedimentation at the bottom of the make sacrifices for the nation?”reservoir, resulting in rockier stream beds andpoorer habitats for the rivers’ aquatic life. Dams Source: S. Sharma, quoted in In the Belly of the River. Tribal conflicts over development in Narmadaalso fragment rivers making it difficult for valley, A. Baviskar, 1995.aquatic fauna to migrate, especially forspawning. The reservoirs that are created onthe floodplains also submerge the existing Irrigation has also changed the croppingvegetation and soil leading to its decomposition pattern of many regions with farmers shiftingover a period of time. to water intensive and commercial crops. This Multi-purpose projects and large dams has great ecological consequences likehave also been the cause of many new social salinisation of the soil. At the same time, it hasmovements like the ‘Narmada Bachao Andolan’ transformed the social landscape i.e.and the ‘Tehri Dam Andolan’ etc. Resistance increasing the social gap between the richerto these projects has primarily been due to the landowners and the landless poor. As we canlarge-scale displacement of local communities. see, the dams did create conflicts betweenLocal people often had to give up their land, people wanting different uses and benefits fromlivelihood and their meagre access and control the same water resources. In Gujarat, theover resources for the greater good of the Sabarmati-basin farmers were agitated andnation. So, if the local people are not benefiting almost caused a riot over the higher priorityfrom such projects then who is benefited? given to water supply in urban areas,Perhaps, the landowners and large farmers, particularly during droughts. Inter-state waterindustrialists and few urban centres. Take the disputes are also becoming common withcase of the landless in a village – does he really regard to sharing the costs and benefits of thegain from such a project? multi-purpose project. WATER RESOURCES 27
  6. 6. India: Major Rivers and Dams28 CONTEMPORARY INDIA – II
  7. 7. triggered floods due to sedimentation in the reservoir. Moreover, the big dams have mostly Do you know that the Krishna-Godavari been unsuccessful in controlling floods at the dispute is due to the objections raised by time of excessive rainfall. You may have seen Karnataka and Andhra Pradesh or read how the release of water from dams governments? It is regarding the diversion during heavy rains aggravated the flood of more water at Koyna by the Maharashtra situation in Maharashtra and Gujarat in 2006. government for a multipurpose project. This The floods have not only devastated life and would reduce downstream flow in their property but also caused extensive soil erosion. states with adverse consequences for Sedimentation also meant that the flood plains agriculture and industry. were deprived of silt, a natural fertiliser, further adding on to the problem of land degradation. It was also observed that the multi-purpose projects induced earthquakes, caused water- Make a list of inter-state water disputes. borne diseases and pests and pollution resulting from excessive use of water. Most of the objections to the projects arosedue to their failure to achieve the purposes for RAINWATER HARVESTINGwhich they were built. Ironically, the dams that Many thought that given the disadvantageswere constructed to control floods have and rising resistance against the multi- Collect information about flood prone areas of the country WATER RESOURCES 29
  8. 8. purpose projects, water harvesting systemwas a viable alternative, both socio-economically and environmentally. In ancientIndia, along with the sophisticated hydraulicstructures, there existed an extraordinarytradition of water-harvesting system. Peoplehad in-depth knowledge of rainfall regimesand soil types and developed wide rangingtechniques to harvest rainwater, groundwater,river water and flood water in keeping withthe local ecological conditions and their waterneeds. In hill and mountainous regions,people built diversion channels like the ‘guls’or ‘kuls’ of the Western Himalayas foragriculture. ‘Rooftop rain water harvesting’was commonly practised to store drinkingwater, particularly in Rajasthan. In the floodplains of Bengal, people developed inundationchannels to irrigate their fields. In arid and (a) Recharge through Hand Pumpsemi-arid regions, agricultural fields wereconverted into rain fed storage structures thatallowed the water to stand and moisten thesoil like the ‘khadins’ in Jaisalmer and ‘Johads’in other parts of Rajasthan. (b) Recharge through Abandoned Dugwell Fig 3.4: Rooftop Rainwater Harvesting • Roof top rain water is collected using a PVC pipe • Filtered using sand and bricks • Underground pipe takes water to sump for immediate usage • Excess water from the sump is taken to the well • Water from the well recharges the underground Fig. 3.3 • Take water from the well (later)30 CONTEMPORARY INDIA – II
  9. 9. rainfall in the world, yet the state capital Shillong faces acute shortage of water. Nearly every household in the city has a roof top rain water harvesting structure. Nearly 15-25 per cent of the total water requirement of the household comes from roof top water harvesting. Find out other rainwater harvesting systemsA kul leads to a circular village tank, as the abovein the Kaza village, from which water is released as existing in and around your locality.and when required. Today, in western Rajasthan, sadly theFig 3.5: Traditional method of rain water harvesting practice of rooftop rainwater harvesting is on the decline as plenty of water is available due to the In the semi-arid and arid regions of perennial Rajasthan Canal, though some housesRajasthan, particularly in Bikaner, Phalodi and still maintain the tankas since they do not likeBarmer, almost all the houses traditionally had the taste of tap water. Fortunately, in many partsunderground tanks or tankas for storing of rural and urban India, rooftop rainwaterdrinking water. The tanks could be as large as harvesting is being successfully adapted to storea big room; one household in Phalodi had a tank and conserve water. In Gendathur, a remotethat was 6.1 metres deep, 4.27 metres long and backward village in Mysore, Karnataka, villagers2.44 metres wide. The tankas were part of the have installed, in their household’s rooftop,well-developed rooftop rainwater harvesting rainwater harvesting system to meet their watersystem and were built inside the main house or needs. Nearly 200 households have installed thisthe courtyard. They were connected to the system and the village has earned the raresloping roofs of the houses through a pipe. Rain distinction of being rich in rainwater. See Fig. 3.6falling on the rooftops would travel down the for a better understanding of the rooftoppipe and was stored in these underground‘tankas’. The first spell of rain was usually notcollected as this would clean the roofs and thepipes. The rainwater from the subsequentshowers was then collected. The rainwater can be stored in the tankastill the next rainfall making it an extremelyreliable source of drinking water when all othersources are dried up, particularly in thesummers. Rainwater, or palar pani, ascommonly referred to in these parts, isconsidered the purest form of natural water.Many houses constructed underground rooms Rooftop harvesting was common across the townsadjoining the ‘tanka’ to beat the summer heat and villages of the Thar. Rainwater that falls onas it would keep the room cool. the sloping roofs of houses is taken through a pipe into an underground tanka (circular holes in the ground). built in the main house or in the courtyard. The picture above shows water being form a Roof top rain water harvesting is the most neighbour’s roof through a long pipe. Here the common practice in Shillong, Meghalaya. neighbour’s rooftop has been used for collection of It is interesting because Cherapunjee and rainwater. The picture shows a hole through which rainwater flows down into an underground tanka. Mawsynram situated at a distance of 55 km. from Shillong receive the highest Fig. 3.6 WATER RESOURCES 31
  10. 10. BAMBOO DRIP IRRIGATION SYSTEM In Meghalaya, a 200-year-old system of tapping stream and spring wate by using bamboo pipes, is prevalent. About 18-20 litres of water enters the bamboo pipe system, gets transported over hundreds of metres, and finally reduces to 20-80 drops per minute ate the site of the plant. Picture 1: Bamboo pipes are used to divert perennial springs on the hilltops to the lower reaches by gravity. Picture 2 and 3: The channel sections, made of bamboo, divert water Picture 4: If the pipes pass a road, to the plant site where it is distributed into branches, again made and they are taken high above the land. laid out with different forms of bamboo pipes. The flow of water into the pipes is controlled by manipulating the pipe positions. Picture 5 and 6 Reduced channel sections and diversion units are used at the last stage of water application. The last channel section enables water to be dropped near the roots of the plant. Fig 3.7rainwater harvesting system which is adaptedhere. Gendathur receives an annual precipitationof 1,000 mm, and with 80 per cent of collection Tamil Nadu is the first and the only stateefficiency and of about 10 fillings, every house in India which has made roof top rainwatercan collect and use about 50,000 litres of water harvesting structure compulsory to all theannually. From the 20 houses, the net amount houses across the state. There are legalof rainwater harvested annually amounts to provisions to punish the defaulters.1,00,000 litres.32 CONTEMPORARY INDIA – II
  11. 11. 1. Collect information on how industries are polluting our water resources. 2. Enact with your classmates a scene of water dispute in your locality. EXERCISES EXERCISES EXERCISES EXERCISES EXERCISES1. Multiple choice questions. (i) Based on the information given below classify each of the situations as ‘suffering from water scarcity’ or ‘not suffering from water scarcity’. (a) Region with high annual rainfall. (b) Region having high annual rainfall and large population. (c) Region having high annual rainfall but water is highly polluted. (d) Region having low rainfall and low population. (ii) Which one of the following statements is not an argument in favour of multi- purpose river projects? (a) Multi-purpose projects bring water to those areas which suffer from water scarcity. (b) Multi-purpose projects by regulating water flow helps to control floods. (c) Multi-purpose projects lead to large scale displacements and loss of livelihood. (d) Multi-purpose projects generate electricity for our industries and our homes. (iii) Here are some false statements. Identify the mistakes and rewrite them correctly. (a) Multiplying urban centres with large and dense populations and urban lifestyles have helped in proper utilisation of water resources. (b) Regulating and damming of rivers does not affect the river’s natural flow and its sediment flow. (c) In Gujarat, the Sabarmati basin farmers were not agitated when higher priority was given to water supply in urban areas, particularly during droughts. (d) Today in Rajasthan, the practice of rooftop rainwater water harvesting has gained popularity despite high water availability due to the Rajasthan Canal.2. Answer the following questions in about 30 words. (i) Explain how water becomes a renewable resource. (ii) What is water scarcity and what are its main causes? (iii) Compare the advantages and disadvantages of multi-purpose river projects.3. Answer the following questions in about 120 words. (i) Discuss how rainwater harvesting in semi-arid regions of Rajasthan is carried out. (ii) Describe how modern adaptations of traditional rainwater harvesting methods are being carried out to conserve and store water. WATER RESOURCES 33