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					                                 WATER RESOURCES
     Very Short Answer Questions of 1 mark each.
   i.   How much water is present on the earth‟s surface?
     Ans. Three-fourth of the earth‟s surface is covered with water but only 3.5% of the
            total volume of earth‟s water is available as freshwater.
  ii.   How the freshwater can be obtained?
     Ans. The freshwater can be obtained directly from precipitation, surface runoff and
            ground water.
 iii.   Explain how the water is being over-exploited in agriculture.
     Ans. To facilitate higher food-grain production, to expand irrigated areas and dry-
            season agriculture the water resources are being over-exploited in India.
 iv.    State the effects of over-exploitation of water resource through tube wells.
     Ans. It may lead to falling groundwater levels, adversely affecting water availability
     and food security of the people.
  v.    Mention the reasons water pollution in India.
     Ans. The bad quality of water is due to pollution by domestic and industrial wastes,
            chemicals, pesticides and fertilizers used in agriculture.
 vi.    Name important hydraulic structures of ancient India.
     Ans. important hydraulic structures built in ancient India are:
        a. In the first century B.C., Sringaverapura near Allahabad had sophisticated
            water harvesting system channelling the flood water of the river Ganga.
        b. During the time of Chandragupta Maurya, dams, lakes and irrigation systems
            were extensively built.
        c. Evidences of sophisticated irrigation works have also been found in Kalinga,
            (Orissa), Nagarjunakonda (Andhra Pradesh), Bennur (Karnataka), Kolhapur
            (Maharashtra), etc.
        d. In the 11th Century, Bhopal Lake, one of the largest artificial lakes of its time
            was built.
        e. In the 14th Century, the tank in Hauz Khas, Delhi was constructed by
            Iltutmish for supplying water to Siri Fort area.

vii.    For what the Narmada Bachao Andolan is famous for?
     Ans. Narmada Bachao Andolan is a Non Governmental Organisation (NGO) that
            mobilised tribal people, farmers, environmentalists and human rights activists
            against the Sardar Sarovar Dam being built across the Narmada river in
            Gujarat. It originally focused on the environmental issues related to trees that
            would be submerged under the dam water. Recently it has re-focused the aim
            to enable poor citizens, especially the oustees (displaced people) to get full
            rehabilitation facilities from the government.
viii.   What is rainwater harvesting?
     Ans. Rainwater harvesting is a technique for capturing and storing rainwater
            through hydro-structures such as recharge through hand pumps and
            abandoned dug well. The technique is: -
                    “Roof top rain water is collected using a PVC pipe. Rainwater is 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. People can take water
                    from the well (later)”




   Created by Suryaveer Singh                                                    Page 1 of 4
Important Question and Answers

Q.1       Describe the water as a renewable resource.
Ans.      Water is renewable resource because all water moves within the hydrological
          cycle and it is recharged and renewed by the hydrological cycle.
Q.2       Mention the important causes of water scarcity in regions of the world.
Ans. Water scarcities in some of the regions of the world are caused by:
   i.     The distribution and availability of water resources is unequal in space and
          time, mainly due to the variations in seasonal and annual precipitation.
  ii.     Water scarcity is caused by over- exploitation of water resources.
 iii.     Excessive use of water for domestic and irrigational uses.
 iv.      Unequal access to water among different social groups.
Q.3       Why many of our regions/cities faces water scarcity although they have ample
          water resources?
Ans. Water scarcity in such regions is due to:
        i.    Large and growing population in a region/city. Having large population
              means greater demands for water for domestic uses.
       ii.    High demand for food-grain production: farmers in order to produce more,
              over-exploit water resources. Farmers expand irrigated areas and cultivate
              crops in dry-season. This may lead to falling groundwater levels and
              adversely affecting water availability.
      iii.    Intensive industrialization: Large industrial units require large amount of
              water of processing of raw materials. They also require power to run them
              which comes from hydroelectric power.
      iv.     Multiplying urban centres: Cities with large and dense populations and
              their urban lifestyles require large amount of water. Most of the urban
              housing societies or colonies have their own groundwater pumping devices
              to meet their water needs. This has resulted in over-exploitation and
              depletion of water resources.
       v.     Bad quality of water: much of water resources may be polluted by
              domestic and industrial wastes, chemicals, pesticides and fertilizers used
              in agriculture, thus, making it hazardous for human use.
Q.4       What may be the effects of over-exploitation and excessive use of water
          resources?
Ans. Over-utilization and mismanagement of water resources may cause:
        i.    Serious health hazards
       ii.    Shortage of availability of food which may adversely effect food security in
              the country.
      iii.    Our livelihoods and productive activities may be affected.
      iv.     Degradation of our natural ecosystems.
       v.     Deplete water resource.
Q.5       Why conservation and management of water resource is necessary?
Ans. Conservation and management of water resource is necessary for:
        i.    Safeguarding ourselves from health hazards,
       ii.    Ensuring food security,
      iii.    Continuation of our livelihoods and productive activities
      iv.     Preventing degradation of our natural ecosystems.
Q.6       Mention how in ancient times we have been conserving and managing the
          water resource?
Ans. From ancient times we have been constructing sophisticated hydraulic
          structures like dams built of stone rubble, reservoirs or lakes, embankments
          and canals for irrigation.
Q.7       Why dams are now referred to as multi-purpose projects?


Created by Suryaveer Singh                                                    Page 2 of 4
Ans.     Dams are built not just for irrigation but for hydel power generation, water
         supply for domestic and industrial uses, conservation of water with flood
         control, recreation, inland navigation and fish breeding. Hence, dams are now
         referred to as multi-purpose projects. In multi-purpose projects many uses of
         the impounded water are integrated with one another. For example, the
         Bhakra – Nangal project, the Hirakud project.
Q.8      Why the multi-purpose projects were called as the temples of modern India?
Ans. Multi-purpose projects were built for integrated water resources management,
         it was thought that they would lead the nation to development and progress;
         it would integrate development of agriculture and the village economy with
         rapid industrialisation and growth of the urban economy.
Q.9      Why the construction of multi-purpose projects and large dams is opposed by
         many people?
Ans. In recent years, multi-purpose projects and large dams have come under
         great scrutiny and opposition for a variety of reasons.
       i.    Regulating and damming of rivers affect their natural flow.
             a. This results in poor sediment flow and excessive sedimentation at the
                 bottom of the reservoir.
             b. Stream beds get rockier.
             c. Destroys the habitat of the rivers‟ aquatic life.
      ii.    Dams also fragment rivers making it difficult for aquatic fauna to migrate,
             especially for spawning.
     iii.    The reservoirs that are created on the floodplains also submerge the
             existing vegetation and soil leading to its decomposition over a period of
             time.
     iv.     Dams displace local communities living in the area.
      v.     Irrigation through dams has also changed the cropping pattern. Many
             farmers are shifting to water intensive and commercial crops. This has
             great ecological consequences like salinisation of the soil.
     vi.     It has transformed the social landscape.
             a. It has increased the social gap between the richer landowners and the
                 landless poor.
             b. The dams create conflicts between people. In Gujarat, the Sabarmati-
                 basin farmers were agitated and almost caused a riot over the higher
                 priority given to water supply in urban areas, particularly during
                 droughts.
             c. Inter-state water disputes are also becoming common with regard to
                 sharing the costs and benefits of the multi-purpose project.
    vii.     Failure to achieve the purposes of controlling floods.
             a. Dams have triggered floods due to sedimentation in the reservoir.
             b. The big dams have been unsuccessful in controlling floods at the time
                 of excessive rainfall.
             c. The floods caused extensive soil erosion.
    viii.    The problem of land degradation has increased by sedimentation.
             a. The flood plains are deprived of silt, a natural fertilizer, coming along
                 with the free river.
     ix.     It was also observed that the multi-purpose projects induced earthquakes,
             caused waterborne diseases and pests and pollution resulting from
             excessive use of water.
Q.10 Why many new social movements are resisting the construction of multi-
         purpose projects and large dams?




Created by Suryaveer Singh                                                   Page 3 of 4
Ans.     Multi-purpose projects and large dams have caused many new social
         movements like the „Narmada Bachao Andolan‟ and the „Tehri Dam Andolan‟
         etc. Resistance to these projects has primarily been due to:
       i.    The large-scale displacement of local communities.
      ii.    Local people often had to give up their land and livelihood
     iii.    They have to give up their available resources for the greater good of the
             nation.
    iv.      Local people are not benefiting from such projects but the landowners and
             large farmers, industrialists and few urban centres are getting all benefits.
Q.11 Describe how the rainwater harvesting was carried out in different parts of
         India.
Ans. In ancient India there existed an extraordinary tradition of water-harvesting
         system. People developed wide ranging techniques to harvest rainwater.
       i.    In hill and mountainous regions, people built diversion channels like the
             „guls‟ or „kuls‟ of the Western Himalayas for agriculture.
      ii.    „Rooftop rain water harvesting‟ was commonly practised to store drinking
             water, particularly in Rajasthan.
     iii.    In the flood plains of Bengal, people developed inundation channels to
             irrigate their fields.
    iv.      In arid and semi-arid regions, agricultural fields were converted into rain
             fed storage structures that allowed the water to stand and moisten the
             soil. Like the „khadins‟ in Jaisalmer and „Johads‟ in other parts of
             Rajasthan.
Q.12 Describe how the rainwater harvesting is carried out in semi-arid and arid
         parts of Rajasthan.
 Ans. In the semi-arid and arid regions of Rajasthan almost all the houses
         traditionally had underground tanks or tankas for storing drinking water.
        i.    They built tanks as large as a big room and were built inside the main
              house;
       ii.    The tankas were part of the well-developed rooftop rainwater harvesting
              system.
      iii.    They were connected to the sloping roofs of the houses through a pipe.
      iv.     Rain falling on the rooftops would travel down the pipe and was stored in
              these underground „tankas‟ till the next rainfall.
       v.     They became an extremely reliable source of drinking water when all
              other sources are dried up, particularly in the summers.
Q.13 Why the practice of rooftop rainwater harvesting is on decline in Rajasthan?
Ans. Today, in western Rajasthan, the practice of rooftop rainwater harvesting is
         on the decline because
        i.    Plenty of water is available due to the perennial Rajasthan Canal.




Created by Suryaveer Singh                                                     Page 4 of 4

				
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