Water Resources

Important Questions
Q. No. 1) Rooftop rainwater harvesting was commonly practiced to store drinking water,
particularly in __________.
Ans. Rajasthan.
Q. No. 2) Explain how water becomes a renewable resource.
Ans. Freshwater is mainly obtained from surface runoff and groundwater 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.
Q. No. 3) Why does the availability of water resources vary over space and time?
Ans. The availability of water resources varies over space and time, mainly due to the
variations in seasonal and annual precipitation.
Q. No. 4) Which state has a 200-year-old system of tapping stream and spring water by
using bamboo pipes?
Ans. Meghalaya.
Q. No. 5) Multipurpose projects and large dams have come under great scrutiny and
opposition. Explain with reason.
Ans. i. Regulating and damming 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.
ii. Dams also fragment rivers making it difficult for aquatic fauna to migrate, especially for
spawning.
iii. The dams have triggered floods due to sedimentation in the reservoir and the release of
excess water during heavy rains.
iv. Multipurpose projects induced earthquakes, caused water-borne diseases, and pests, and
lead to pollution resulting from excessive use of water.
Q. No. 6) How is agriculture responsible for creating stress on water resources? Suggest
any one solution for it.
Ans. i. To facilitate higher food-grain production, water resources are being over-exploited to
expand irrigated areas for dry-season agriculture.
ii. Irrigated agriculture is the largest consumer of water.
iii. Most farmers have their own wells and tube wells on their farms for irrigation to increase
their productivity. This lead to falling groundwater levels, adversely affecting water availability
and food security of the people.
Q. No. 7) What are the diversion channels of the Western Himalayas called?
Ans. Guls or Kuls.
Q. No. 8) Intensive industrialization and urbanization exerted pressure on existing freshwater
resources. Justify the statement with suitable examples.
Ans. i. Post-independent India witnessed intensive industrialization and urbanization.
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.
iv. Much of this energy comes from hydroelectric power.
v. Today, in India hydroelectric power contributes approximately 22% of the total electricity
produced.
vi. Multiplying urban centers with large and dense populations and urban lifestyles has not
only added to water and energy requirements but has further aggravated the problem.
vii. Most of the housing societies or colonies in the cities have their own groundwater
pumping devices, which result in the over-exploitation of fragile water resources.
Q. No. 9) On which river Bhakra-Nangal Dam has been constructed?
Ans. Sutluj.
Q. No. 10) The Hirakud project in the ________ basin integrated the conservation of water
with flood control.
Ans. Mahanadi.
Q. No. 11) How are multipurpose projects and large dams the cause of social movements?
Ans. i. Multi-purpose projects and large dams have been the cause of many new
environmental movements like the ‘Narmada Bachao Andolan’ and the ‘Tehri Dam Andolan’.
ii. Resistance to these projects has primarily been due to the large-scale displacement of
local communities.
iii. 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.
iv. But these local people are not benefited much from these projects. The benefited ones
are the landowners and large farmers, industrialists, and a few urban centers.
Q. No. 12) Who proclaimed dams as the temples of modern India? Why?
Ans. Jawaharlal Nehru proclaimed the dams as the ‘Temples of modern India’ because
i. They integrate the development of agriculture and the village economy with rapid
industrialization and growth of the urban economy.
ii. They provide water for irrigation.
iii. They provide water for electricity generation
iv. Provide water supply for domestic and industrial uses.
v. Helps in flood control.
vi. Provide recreation
vii. Helps in inland navigation.
viii. Useful for fish breeding.
Q. No. 13) What is the need for rainwater harvesting?
Ans. i. Rainwater harvesting is needed to provide it for agriculture, collect drinking water,
irrigate the fields, and to moisten the soil.
ii. Rainwater harvesting is a viable alternative, both socio-economically and environmentally
to multipurpose projects.
Q. No. 14) What is a multipurpose river valley project? Mention any four objectives of it.
Ans. A project where many uses of the impounded water are integrated with one another is
known as a multipurpose project. It is built for –
i. Irrigation
ii. Electricity generation
iii. Water supply for domestic and industrial uses
iv. Flood control
v. Recreation
vi. Inland navigation
vii. Fish breeding.
Q. No. 15) What is water scarcity and what are its main causes?
Ans. Water scarcity is the lack of freshwater resources to meet the demands of water usage
within a region.
Main causes of water scarcity:
i. Water scarcity in most cases is caused by over-exploitation, excessive use, and unequal
access to water among different social groups.
ii. Water scarcity may be an outcome of a large and growing population and consequent
greater demands for water and unequal access to it.
iii. To facilitate higher food-grain production, water resources are being over-exploited to
expand irrigated areas for dry-season agriculture.
iv. Intensive industrialization and urbanization exerted pressure on existing freshwater
resources.
v. Even if water is sufficiently available to meet the needs of the people, much of it is maybe
polluted by domestic and industrial wastes, chemicals, pesticides, and fertilizers used in
agriculture, thus causing water scarcity.
Q. No. 16) Explain the working of underground tanks as a part of rooftop rainwater
harvesting system practiced in Rajasthan.
Or,
What do you understand by Palar Pani? How Palar Pani is collected?
Ans. Rainwater is commonly referred to as Palar Pani in the arid and semi-arid regions of
Rajasthan.
i. In the semi-arid and arid regions of Rajasthan, particularly in Bikaner, Phalodi, and Barmer,
almost all the houses traditionally had underground tanks for storing drinking water.
ii. The tanks could be as large as a big room.
iii. The tanks were part of the well-developed rooftop rainwater harvesting system.
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 tanks.
vi. The first spell of rain was usually not collected as this would clean the roofs and the
pipes.
vii. The rainwater from the subsequent showers was then collected.
Q. No. 17) Analyze the importance of rooftop rainwater harvesting in Rajasthan.
Ans. i. It was commonly practiced to store drinking water.
ii. The rainwater can be stored in the tanks till the next rainfall, making it an extremely
reliable source of drinking water when all other sources are dried up, particularly in the
summers.
iii. Rainwater (Palar Pani) is considered the purest form of natural water.
iv. Many houses construct underground rooms adjoining the ‘tanks’ to beat the summer heat
as it would keep the room cool.
v. Some houses still maintain the tanks since they do not like the taste of tap water.
Q. No. 18) Describe any three traditional methods of rainwater harvesting adopted in
different parts of India.
Ans. i. In hill and mountainous regions, people built diversion channels like the ‘guls’ or ‘kuls’
of the Western Himalayas for agriculture.
ii. ‘Rooftop rainwater harvesting’ was commonly practiced to store drinking water, particularly
in Rajasthan.
iii. In the flood plains of Bengal, people developed inundation channels to irrigate their fields.
iv. In semi-arid and 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. No. 19) Compare the advantages and disadvantages of multi-purpose river valley
projects.
Ans. Advantages:
i. They provide water for irrigation.
ii. They provide water for electricity generation
iii. Provide water supply for domestic and industrial uses.
iv. Helps in flood control.
v. Provide recreation
vi. Helps in inland navigation.
vii. Useful for fish breeding.
Disadvantages:
i. 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.
ii. Dams also fragment rivers making it difficult for aquatic fauna to migrate, especially for
spawning.
iii. The dams have triggered floods due to sedimentation in the reservoir and the release of
excess water during heavy rains.
iv. Multipurpose projects induced earthquakes, caused water-borne diseases, and pests, and
lead to pollution resulting from excessive use of water.
v. Irrigation has changed the cropping pattern of many regions with farmers shifting to
water-intensive and commercial crops. This has great ecological consequences like
salinization of the soil.
vi. The dams increase the social gap between the richer landowners and the landless poor.
vii. The dams create inter-state water disputes with regard to sharing the costs and benefits
of the multi-purpose project.
Q. No. 20) What is Bamboo Drip Irrigation? Mention any two features of it.
Ans. The Bamboo Drip Irrigation system is a 200-year-old system of tapping stream and
spring water by using bamboo pipes and transporting water from higher to lower regions with
the help of gravity.
Features:
i. 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 at the site of the plant.
ii. The flow of water into the pipes is controlled by manipulating the pipe positions.
iii. If the pipes pass a road, they are taken high above the land.