Water Resources Class 10 Questions and Answers
3 marks questions
1.What is water scarcity and what are its main causes?
Answer- Shortage of water for a sustained period is called water scarcity. Growing population, over-exploitation and unequal distribution of water among social groups are the main causes of water scarcity.
2. In recent years, multi-purpose projects and large dams has come under great scrutiny and opposition for a variety of reasons. Explain any three.
I. Regulating and damming of river affect their natural flow causing poor sediment flow and excessive sedimentation at the bottom of the reservoir, resulting in rockier stream.
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.
3.Explain how water becomes a renewable resource.
Answer- 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.
5 marks question
1. Describe how modern adaptations of traditional rainwater harvesting Methods are being carried out to conserve and store water.
Answer: Several low cost techniques are now available to recharge groundwater and harvest the rainwater like;
(i) (a) construction of percolation ponds. (b) Refilling of dug wells. (C) Collection of rainwater and storing it in tanks or underground.
(ii) Rooftop rainwater is collected through a pipe into the underground tanks. Rooftop rainwater harvesting is practiced in Shillong and Meghalaya where nearly 15 to 25% of actual water requirement is met from rooftop water harvesting.
(iii) In many parts of rural and urban India, rooftop rainwater harvesting is successfully adopted to conserve and store water.
(iv) In Gendathur a village in Karnataka nearly 200 households have installed this system. From 20 houses, the net amount of rainwater harvested amounts to 1,00,000 litres annually.
(v) In Meghalaya, Bamboo drip is practised to transport stream and spring water by using Bamboo pipes.
2. How do dams help us in conserving and managing water?
Answer- Dams were traditionally built to impound rivers and rain water that could be used later to irrigate agricultural fields. Today, dams are built not just for irrigation but for –
i) electricity generation,
ii) Water supply for domestic and industrial uses
iii) flood control
v) inland navigation and fish breeding
Hence, dams are now referred to as multi-purpose projects where the many uses of the Impounded water are integrated with one another. For example, in the Sutluj-Beas river basin, the Bhakra – Nangal project water is being used both for hydel power production and irrigation. Similarly, the Hirakud project in the Mahanadi basin integrates conservation of water with flood control
Source Based Questions:
Source 1: “Hydraulic Structures in Ancient India”
In the first century B.C, Sringaverapura near Allahabad had sophisticated water harvesting system channeling the flood water of the river Ganga. During the time of Chandragupta Maurya, dams, lakes and irrigation systems were extensively built. Evidences of sophisticated irrigation works have also been found in Kalinga, (Odisha), Nagarjunakonda (Andhra Pradesh), Bennur (Karnataka), Kolhapur (Maharashtra), etc. In the 11th Century, Bhopal Lake, one of the largest artificial lakes of its time was built. In the 14th Century, the tank in Hauz Khas, Delhi was constructed by Iltutmish for supplying water to Siri Fort area.
With the help of above paragraph answer the following questions.
1. In which century Bhopal lake was formed?
Ans: 11th Century
2. _________ Delhi was constructed by Iltutmish for supplying water to Siri Fort area.
Ans: Hauz Khas
3. State whether the sentence is true or false, During the time of Chandragupta Maurya, Dams, lakes and irrigation systems were extensively built.
Rooftop rainwater harvesting is the most common practice in Shillong, Meghalaya.
It is interesting because Cherapunjee and Mawsynram situated at a distance of55 km. From Shillong receive the highest train fall in the world, yet the state capital Shillong faces acute shortage of water. Nearly every household in the city has a rooftop rainwater harvesting structure. Nearly 15-25 per cent of the total water requirement of the household comes from rooftop water harvesting. Tamil Nadu is the first state in India which has made rooftop rainwater harvesting structure compulsory to all the houses across the state. There are legal provisions to punish the defaulters.
With the help of above paragraph answer the following questions
1. Name the Indian state which has made Rooftop rainwater harvesting structure compulsory to all the houses across the state.
Ans: Tamil Nadu is the first state in India Which has made rooftop rain water Harvesting structure compulsory to all the houses across the state.
2. ______capital of Meghalaya receives highest rainfall in the world
3. State whether the sentence is true or false yet the state capital Shillong faces acute shortage of water.