Water Resource

Three-fourth of the earth’s surface is covered with water, but only a small proportion of it accounts for freshwater
that can be put to use. This freshwater is mainly obtained from surface run off and ground water that is
continually being renewed and recharged through the hydrological cycle. All water moves within the hydrological
cycle ensuring that water is a renewable resource.

Importance of water:
1) Domestic use
2) Useful in food production
3) Industrial use
4) Electricity production
5) Use in transportation
6) Useful as a water vapour in atmosphere
7) Presence of water makes Earth a unique Planet ( needs to explain)

Some Facts about water:

1) 96.5 per cent of the total volume of world’s water is estimated to exist as oceans and only 2.5 per cent as fresh
water. Nearly 70 per cent of this freshwater occurs as ice sheets and glaciers in Antarctica, Greenland and the
mountainous regions of the world, while a little less than 30 per cent is stored as groundwater in the world’s
aquifers.
2) India receives nearly 4 per cent of the global precipitation and ranks 133 in the world in terms of water
availability per person per annum.
3) The total renewable water resources of India are estimated at 1,897 sq km per annum.
4) By 2025, it is predicted that large parts of India will join countries or regions having absolute water scarcity.

Why is it predicted that by 2025, nearly two billion people will live in absolute water scarcity?

What is water scarcity?

According to Falken Mark, a Swedish expert, water stress occurs when water availability is less than 1,000 cubic meter per
person per day.

The availability of water resources varies over space and time- Mainly due to the variations in seasonal and
annual precipitation

Water scarcity- Causes

1. Intense pressure due to growing population:
I. A large population means- more water not only for domestic use but also to produce more food.
II. Higher food-grain production
III. Water resources are being over-exploited to expand irrigated areas and dry-season agriculture.
IV. Most farmers have their own wells and tube-wells in their farms for irrigation to increase their
produce.
V. It may lead to falling groundwater levels, adversely affecting water availability and food security of
the people.
Due to Industrialisation and Urbanisation:
I. Large industrial houses are as commonplace as the industrial units of many MNCs.

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II. The ever increasing number of industries has made matters worse by exerting pressure on existing
freshwater resources.
III. Industries, apart from being heavy users of water, also require power to run them. Much of this energy
comes from hydroelectric power.
IV. Multiplying urban centers with large and dense populations and urban lifestyles have not only added to
water and energy requirements but have further aggravated the problem.
V. Housing societies or colonies in the cities have their own groundwater pumping devices to meet their water
needs.
Due to Pollution:
I. This scarcity may be due to bad quality of water.
II. Much of it may be polluted by domestic and industrial wastes, chemicals, pesticides and fertilisers used in
agriculture, thus, making it hazardous for human use.

Case study- Toxic Rivers:

1. India’s rivers, especially the smaller ones, have all turned into toxic streams.
2. And even the big ones like the Ganga and Yamuna are far from being pure.
3. The assault on India’s rivers – from population growth, agricultural modernisation, urbanisation and industrialisation.

Why there is a need to conserve and manage water?

1. To safeguard ourselves from health hazards.
2. To ensure food security.
3. For continuation of our livelihoods and productive activities.
4. To prevent degradation of our natural ecosystems.

Hydraulic structure: A construction to store and collect rain water is called hydraulic structure.

Hydraulic Structures in Ancient India

I. In the first century B.C., Sringaverapura near Allahabad had sophisticated water harvesting system channeling the
flood water of the river Ganga.
II. During the time of Chandragupta Maurya, dams, lakes and irrigation systems were extensively built.
III. Evidences of sophisticated irrigation works have also been found in Kalinga, (Orissa), Nagarjunakonda (Andhra
Pradesh), Bennur (Karnataka), Kolhapur (Maharashtra), etc.
IV. In the 11th Century, Bhopal Lake, one of the largest artificial lakes of its time was built.
V. In the 14th Century, the tank in Hauz Khas, Delhi was constructed by Iltutmish for supplying water to Siri Fort area.

What are Dams?

1) A dam is a barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or
impoundment.
2) “Dam” refers to the reservoir rather than the structure.
3) Most dams have a section called a spillway or weir over which or through which it is intended that water will flow
either intermittently or continuously.

Types of Dams: Dams are classified according to structure, intended purpose or height.
1) Based on structure and the materials used- timber dams, embankment dams or masonry dams, with several
subtypes.
2) According to the height, dams can be categorised as large dams, low dams, medium height dams and high dams.

Why dams are termed as multipurpose dams:

1) Dams are built not just for irrigation but for electricity generation, water supply for domestic and industrial
uses, flood control, recreation, inland navigation and fish breeding.

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2) Hence, dams are now referred to as multi-purpose projects where the many uses of the impounded water
are integrated with one another.
3) For example, in the Sutluj-Beas river basin, the Bhakra – Nangal project water is being used both for hydel
power production and irrigation. Hirakud project in the Mahanadi basin integrates conservation of water
with flood control.
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’? Why
The reason is that it would integrate development of agriculture and the village economy with rapid
industrialisation and growth of the urban economy.

In recent years, multi-purpose projects and large dams have come under great scrutiny and opposition for a
variety of reasons. Why?
1) Regulating and damming of rivers affect their natural flow causing poor sediment flow and excessive
sedimentation at the bottom of the reservoir, resulting in rockier stream beds and poorer habitats for the
rivers’ aquatic life.
2) Dams also fragment rivers making it difficult for aquatic fauna to migrate, especially for spawning.
3) The reservoirs that are created on the floodplains also submerge the existing vegetation and soil leading to
its decomposition over a period of time.
4) Multi-purpose projects and large dams have also been the cause of many new social movements like the
‘Narmada Bachao Andolan’ and the ‘Tehri Dam Andolan’ etc.
I. Resistance to these projects has primarily been due to the large-scale displacement of local
communities.
II. Local people often had to give up their land, livelihood and their meager access and control over
resources for the greater good of the nation.
III. The local people are not benefiting from such projects. Perhaps, the landowners and large farmers,
industrialists and few urban centers.
5) Irrigation has also changed the cropping pattern of many regions with farmers shifting to water intensive
and commercial crops. This has great ecological consequences like salinisation of the soil.
6) It has transformed the social landscape i.e. increasing the social gap between the richer landowners and the
landless poor.
7) The dams did create conflicts between people wanting different uses and benefits from the same water
resources. 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.
8) Inter-state water disputes are also becoming common with regard to sharing the costs and benefits of the
multi-purpose project.
9) The dams that were constructed to control floods have triggered floods due to sedimentation in the
reservoir.
10) The big dams have mostly been unsuccessful in controlling floods at the time of excessive rainfall. The
release of water from dams during heavy rains aggravated the flood situation in Maharashtra and Gujarat in
2006.
11) The floods have not only devastated life and property but also caused extensive soil erosion. Sedimentation
also meant that the flood plains were deprived of silt, a natural fertiliser, further adding on to the problem
of land degradation.

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Narmada Bachao Andolan/Save Narmada Movement: It 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.
1) It originally focused on the environmental issues related to trees that would be submerged under the dam water.
2) Recently it has re-focused the aim to enable poor citizens, especially the oustees (displaced people) to get full
rehabilitation facilities from the government.
3) People felt that their suffering would not be in vain… accepted the trauma of displacement believing in the promise of
irrigated fields and plentiful harvests.
4) The survivors of Rihand told that they accepted their sufferings as sacrifice for the sake of their nation. But after thirty
bitter years of being adrift, their livelihood having even being more precarious.
They keep asking: “Are we the only ones chosen to make sacrifices for the nation?”

The Krishna-Godavari River water dispute is due to the objections raised by Karnataka and Andhra Pradesh
governments? It is regarding the diversion of more water at Koyna by the Maharashtra government for a
multipurpose project. This would reduce downstream flow in their states with adverse consequences for
agriculture and industry.

Rainwater Harvesting: A viable alternative, both socioeconomically and environmentally. In ancient India an
extraordinary tradition of water-harvesting system was existed. People had in-depth knowledge of rainfall regimes
and soil types and developed wide ranging techniques to harvest rainwater, groundwater, river water and flood
water in keeping with the local ecological conditions and their water needs.
Some Traditional Rain Water Harvesting Practices:
1) Kuls and Guls: In hill and mountainous regions, people built diversion channels like the ‘guls’ or ‘kuls’ of
the Western Himalayas for agriculture.
2) Rooftop rain water harvesting: It was commonly practised to store drinking water, particularly in
Rajasthan.

Tankas:
i. In Bikaner, Phalodi and Barmer, almost all the houses traditionally had underground tanks or
Tankas for storing drinking water.
ii. The tanks could be as large as a big room; one household in Phalodi had a tank that was 6.1
meters deep, 4.27 meters long and 2.44 meters wide.
iii. The Tankas were part of the well-developed rooftop rainwater harvesting system and were built
inside the main house or the courtyard.
iv. They were connected to the sloping roofs of the houses through a pipe.
v. Rain falling on the rooftops would travel down the pipe and was stored in these underground
‘Tankas’.
vi. The first spell of rain was usually not collected as this would clean the roofs and the pipes.

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vii. The rainwater from the subsequent showers was then collected.
viii. The rain water in the Tankas commonly referred as Palarpani Many houses constructed
underground rooms adjoining the ‘Tankas’ to beat the summer heat as it would keep the room
cool.
Today, in western Rajasthan, sadly the practice of rooftop rainwater harvesting is on the decline as
plenty of water is available due to the perennial Rajasthan Canal, though some houses still maintain the
Tankas since they do not like the taste of tap water.
3) Inundation channels: In the flood plains of Bengal, people developed inundation channels to irrigate their
fields.
4) Khadins and Johads: In arid and semi-arid regions of Rajasthan, 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.

Gendathur
1) A remote backward village in Mysore, Karnataka, villagers has installed, in their household’s rooftop,
rainwater harvesting system to meet their water needs.
2) Nearly 200 households have installed this system and the village has earned the rare distinction of being
rich in rainwater.
3) Gendathur receives an annual precipitation of 1,000 mm, and with 80 per cent of collection efficiency and
of about 10 fillings, every house can collect and use about 50,000 liters of water annually.
4) From the 20 houses, the net amount of rainwater harvested annually amounts to 1, 00,000 liters.

Shillong:
1) Roof top rain water harvesting is the most common practice in Shillong, Meghalaya.
2) It is interesting because Cherrapunjee and Mawsynram situated at a distance of 55 km. from Shillong
receive the highest rainfall in the world, yet the state capital Shillong faces acute shortage of water.
3) Every household in the city has a roof top rain water harvesting structure.
4) Nearly 15-25 per cent of the total water requirement of the household comes from roof top water
harvesting.

BAMBOO DRIP IRRIGATION SYSTEM:

1) In Meghalaya, a 200-year-old system of tapping stream and spring water by using bamboo pipes is
prevalent.
2) About 18-20 liters of water enters the bamboo pipe system, gets transported over hundreds of meters, and
finally reduces to 20-80 drops per minute ate the site of the plant.

Tamil Nadu is the first and the only state in India which has made roof top rainwater harvesting structure
compulsory to all the houses across the state. There are legal provisions to punish the defaulters.

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