Class 10 - Chapter 3: Water Resources

1. 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.
Answer: Not suffering from water scarcity.

(b) Region having high annual rainfall and large population.
Answer: Suffering from water scarcity.

(c) Region having high annual rainfall but water is highly polluted.
Answer: Suffering from water scarcity.

(d) Region having low rainfall and low population.
Answer: Not suffering from water scarcity.

(ii) Which one of the following statements is not an argument in favour of multi-purpose river projects?

Answer: (c) Multi-purpose projects lead to large scale displacements and loss of livelihood.

(iii) Here are some false statements. Identify the mistakes and rewrite them correctly.

(a) Incorrect Statement:
Multiplying urban centres with large and dense populations and urban lifestyles have helped in proper utilisation of water resources.

Correct Statement:
Multiplying urban centres with large and dense populations and urban lifestyles have led to over-exploitation and mismanagement of water resources.

(b) Incorrect Statement:
Regulating and damming of rivers does not affect the river's natural flow and its sediment flow.

Correct Statement:
Regulating and damming of rivers affect the river's natural flow and its sediment flow.

(c) Incorrect Statement:
Today in Rajasthan, the practice of rooftop rainwater harvesting has gained popularity despite high water availability due to the Indira Gandhi Canal.

Correct Statement:
Today in Rajasthan, rooftop rainwater harvesting is being encouraged because many areas still face water scarcity and need sustainable water conservation methods.

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2. Answer the Following Questions in About 30 Words

(i) Explain how water becomes a renewable resource.

Answer:
Water becomes a renewable resource because it is continuously renewed through the hydrological cycle. Processes such as evaporation, condensation and precipitation constantly replenish water supplies on the Earth.

(ii) What is water scarcity and what are its main causes?

Answer:
Water scarcity is the shortage of sufficient usable water to meet human needs. Its main causes are overpopulation, urbanisation, industrialisation, excessive irrigation, pollution and unequal distribution of rainfall.

(iii) Compare the advantages and disadvantages of multi-purpose river projects.

Answer:
Advantages include irrigation, flood control, hydroelectric power generation, water supply and navigation. Disadvantages include displacement of people, environmental degradation, loss of biodiversity and disruption of natural river ecosystems.

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3. Answer the Following Questions in About 120 Words

(i) Discuss how rainwater harvesting in semi-arid regions of Rajasthan is carried out.

Answer:
In the semi-arid regions of Rajasthan, rainwater harvesting has been practised for centuries using traditional methods. People construct structures such as tanks, johads, khadins and underground storage tanks to collect and store rainwater. Rooftop rainwater harvesting is also common, where rainwater from roofs is directed through pipes into underground tanks. These tanks store water for drinking and domestic use throughout the year. In rural areas, khadins are built to capture surface runoff and increase soil moisture for agriculture. Such methods help conserve water in regions with low rainfall and provide a reliable source of water during dry periods. Rainwater harvesting has greatly contributed to water conservation and sustainable resource management in Rajasthan.

(ii) Describe how modern adaptations of traditional rainwater harvesting methods are being carried out to conserve and store water.

Answer:
Modern rainwater harvesting systems have adapted traditional methods by using advanced technology and improved storage facilities. Rooftop rainwater harvesting systems collect rainwater through pipes and store it in tanks or recharge pits. In urban areas, rainwater is directed into borewells and groundwater recharge structures to replenish underground water reserves. Schools, offices, residential buildings and industries are increasingly installing rainwater harvesting systems. Filters are used to remove impurities before storage. Many state governments have made rainwater harvesting mandatory in new buildings. These modern adaptations reduce dependence on groundwater, prevent water scarcity, increase groundwater levels and promote sustainable use of water resources for future generations.