Chapter 3 — Water Resources

Overview

Water Resources begins with a paradox: three-quarters of the earth's surface is covered with water, water is a renewable resource, and yet water scarcity is one of the defining problems of contemporary India. The chapter resolves the paradox with the figures - 96.5 per cent of the total volume of the world's water is in the oceans, only 2.5 per cent is fresh water, nearly 70 per cent of that is frozen in the ice sheets of Antarctica, Greenland and the mountains, and less than 30 per cent is stored as groundwater. India receives nearly 4 per cent of the world's precipitation and ranks very low in water availability per person per year. It then argues that scarcity is caused not only by shortage but by over-exploitation, excessive use and unequal access - by a growing population, by irrigation for high-yielding varieties, by industrialisation, and by urbanisation with its private wells and housing societies drilling their own borewells. The chapter then examines the twentieth century's chosen answer, the multi-purpose river project, which Nehru called the temple of modern India, and sets out the case for it - irrigation, electricity, flood control, navigation, fish breeding - alongside the objections that have accumulated against it: sedimentation, damage to aquatic life, submergence and displacement, induced earthquakes, and the movements such as the Narmada Bachao Andolan that grew from them. It closes with the alternative: rainwater harvesting, in its traditional Indian forms - guls and kuls, khadins and johads, inundation channels, tankas and bamboo drip irrigation - and in modern rooftop form, which Tamil Nadu made compulsory for every house in the state.

Learning Objectives

• Explain why water scarcity occurs even though water is a renewable resource.
• State the distribution of the world's water among oceans, ice and groundwater.
• Explain how a growing population, irrigation, industrialisation and urbanisation cause water scarcity.
• Explain how water quality, and not only quantity, contributes to scarcity.
• Define a multi-purpose river project and list the purposes it serves.
• Name the major multi-purpose projects of India and the rivers on which they are built.
• State the objections raised against multi-purpose river projects.
• Describe the Narmada Bachao Andolan and the concerns it raised.
• Describe the traditional methods of rainwater harvesting in different regions of India.
• Describe rooftop rainwater harvesting and the case of Gendathur and of Tamil Nadu.

Topics in this chapter

5 topics · tap a topic title to jump straight to it.

Key Concepts

Hydrological cycle

The continuous movement of water that renews and recharges surface run-off and groundwater, making water a renewable resource.

Water scarcity

Shortage of usable water, caused not only by low availability but by over-exploitation, excessive use, unequal access and pollution.

Aquifer

An underground layer of rock or sediment that stores groundwater - holding a little under 30 per cent of the world's freshwater.

Multi-purpose river project

A dam project in which the many uses of impounded water - irrigation, electricity, water supply, flood control, navigation, recreation, fish breeding - are integrated with one another.

Dam

A barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or impoundment.

Spillway

The section of a dam, also called a weir, over or through which water is intended to flow.

Sedimentation

The settling of silt at the bottom of a reservoir, which reduces storage, starves the downstream river of sediment and can itself trigger floods.

Narmada Bachao Andolan

The movement against the Sardar Sarovar Dam, raised primarily over large-scale displacement of local communities.

Guls and kuls

Diversion channels built in the Western Himalayas to carry water for agriculture.

Khadins

Rain-fed storage structures of Jaisalmer, in which agricultural fields let water stand and moisten the soil.

Johads

Rain-fed storage structures found in other parts of Rajasthan, serving the same purpose as khadins.

Inundation channels

Channels developed in the flood plains of Bengal to irrigate fields with flood water.

Tankas

Underground tanks of Bikaner, Phalodi and Barmer, connected to sloping roofs by pipes, storing rooftop rainwater for drinking.

Palar pani

The local name for rainwater in parts of Rajasthan, considered the purest form of natural water.

Rooftop rainwater harvesting

Collecting rain falling on a roof and storing it, made compulsory for all houses in Tamil Nadu.

Bamboo drip irrigation

The 200-year-old Meghalaya system of tapping stream and spring water in bamboo pipes, delivering 20-80 drops per minute at the plant.

1. What is meant by water scarcity, and is it only caused by less rainfall? / जल दुर्लभता से क्या तात्पर्य है, और क्या यह केवल कम वर्षा के कारण होती है?
   Show answer

   Water scarcity is the shortage of water relative to its demand. It is not caused only by low rainfall; it can result from over-exploitation, excessive use and unequal access to water among different social groups, even in areas that receive adequate rainfall. / जल दुर्लभता माँग की तुलना में जल की कमी है। यह केवल कम वर्षा के कारण नहीं होती; यह अति-दोहन, अत्यधिक उपयोग और विभिन्न सामाजिक समूहों के बीच जल तक असमान पहुँच से भी हो सकती है, यहाँ तक कि पर्याप्त वर्षा वाले क्षेत्रों में भी।

2. Why are dams referred to as 'multipurpose projects'? / बाँधों को 'बहुउद्देशीय परियोजनाएँ' क्यों कहा जाता है?
   Show answer

   Dams are called multipurpose projects because the water stored is used for many purposes together, such as irrigation, generation of electricity (hydel power), water supply for domestic and industrial use, flood control, recreation, inland navigation and fish breeding. / बाँधों को बहुउद्देशीय परियोजनाएँ इसलिए कहा जाता है क्योंकि संग्रहीत जल का उपयोग एक साथ कई उद्देश्यों के लिए होता है, जैसे सिंचाई, बिजली उत्पादन (जल विद्युत), घरेलू और औद्योगिक उपयोग हेतु जल आपूर्ति, बाढ़ नियंत्रण, मनोरंजन, अंतर्देशीय नौचालन और मछली पालन।

3. Why did Jawaharlal Nehru call dams the 'temples of modern India'? / जवाहरलाल नेहरू ने बाँधों को 'आधुनिक भारत के मंदिर' क्यों कहा?
   Show answer

   Nehru proudly called dams the 'temples of modern India' because they were expected to integrate development of agriculture and the village economy with rapid industrialisation and growth of the urban economy, symbolising the progress and self-reliance of independent India. / नेहरू ने गर्व से बाँधों को 'आधुनिक भारत के मंदिर' इसलिए कहा क्योंकि उनसे कृषि और ग्रामीण अर्थव्यवस्था के विकास को तीव्र औद्योगीकरण और शहरी अर्थव्यवस्था की वृद्धि के साथ एकीकृत करने की अपेक्षा थी, जो स्वतंत्र भारत की प्रगति और आत्मनिर्भरता का प्रतीक थे।

4. State any two objections raised against large multipurpose river projects. / बड़ी बहुउद्देशीय नदी परियोजनाओं के विरुद्ध उठाई गई कोई दो आपत्तियाँ बताइए।
   Show answer

   Multipurpose projects regulate and divert rivers, affecting their natural flow and causing poor sediment flow and rockier riverbeds. They also submerge land and displace local people, fragment aquatic life, and have triggered movements like the Narmada Bachao Andolan against displacement and environmental damage. / बहुउद्देशीय परियोजनाएँ नदियों को नियंत्रित और मोड़ती हैं, जिससे उनका प्राकृतिक प्रवाह प्रभावित होता है और कम तलछट प्रवाह तथा अधिक पथरीली नदीतलियाँ बनती हैं। ये भूमि को जलमग्न और स्थानीय लोगों को विस्थापित भी करती हैं, जलीय जीवन को खंडित करती हैं, और विस्थापन तथा पर्यावरणीय क्षति के विरुद्ध नर्मदा बचाओ आंदोलन जैसे आंदोलनों को जन्म दिया है।

5. What is rainwater harvesting? Why is it being encouraged? / वर्षा जल संग्रहण क्या है? इसे क्यों प्रोत्साहित किया जा रहा है?
   Show answer

   Rainwater harvesting is the technique of capturing and storing rainwater for future use, often to recharge groundwater. It is being encouraged because it is a viable alternative, both socio-economically and environmentally, to large dams, and helps overcome local water scarcity. / वर्षा जल संग्रहण भविष्य के उपयोग हेतु वर्षा जल को एकत्र और संग्रहीत करने की तकनीक है, जो प्रायः भूजल को पुनर्भरित करने के लिए होती है। इसे इसलिए प्रोत्साहित किया जा रहा है क्योंकि यह बड़े बाँधों का सामाजिक-आर्थिक और पर्यावरणीय दोनों दृष्टि से एक व्यवहार्य विकल्प है और स्थानीय जल दुर्लभता दूर करने में सहायता करता है।

6. Describe the traditional rainwater harvesting methods used in Rajasthan and the hills of the western Himalayas. / राजस्थान तथा पश्चिमी हिमालय की पहाड़ियों में प्रयुक्त पारंपरिक वर्षा जल संग्रहण विधियों का वर्णन कीजिए।
   Show answer

   In the semi-arid regions of Rajasthan, especially Bikaner, Phalodi and Barmer, households traditionally built underground tanks called tankas to store drinking water collected from rooftop rainwater. In the hilly western Himalayas, people built diversion channels like the 'guls' or 'kuls' to carry water for agriculture. / राजस्थान के अर्ध-शुष्क क्षेत्रों में, विशेषकर बीकानेर, फलोदी और बाड़मेर में, घरों में पारंपरिक रूप से छत के वर्षा जल से एकत्र पेयजल संग्रह हेतु 'टाँका' नामक भूमिगत टंकियाँ बनाई जाती थीं। पहाड़ी पश्चिमी हिमालय में लोग कृषि हेतु जल ले जाने के लिए 'गुल' या 'कुल' जैसी विसर्जन नालियाँ बनाते थे।

7. How can multipurpose projects sometimes increase the risk of floods? / बहुउद्देशीय परियोजनाएँ कभी-कभी बाढ़ का खतरा कैसे बढ़ा सकती हैं?
   Show answer

   Although built partly for flood control, dams can fail to control floods at times of excessive rainfall, and sedimentation reduces their water storage capacity. The release of large amounts of stored water during heavy rains can cause severe floods downstream, as has happened in some river projects. / यद्यपि आंशिक रूप से बाढ़ नियंत्रण हेतु बनाए जाते हैं, बाँध अत्यधिक वर्षा के समय बाढ़ नियंत्रित करने में विफल रह सकते हैं, और तलछट जमाव उनकी जल भंडारण क्षमता घटा देता है। भारी वर्षा के दौरान बड़ी मात्रा में संग्रहीत जल छोड़ने से निचले क्षेत्रों में भीषण बाढ़ आ सकती है, जैसा कुछ नदी परियोजनाओं में हुआ है।

8. Why is it important to conserve water resources even though water is a renewable resource? / यद्यपि जल एक नवीकरणीय संसाधन है, फिर भी जल संसाधनों का संरक्षण क्यों महत्वपूर्ण है?
   Show answer

   Although water is renewable through the hydrological cycle, growing population, rising agricultural and industrial demand, over-exploitation of groundwater and pollution have made fresh, usable water increasingly scarce. Conservation and management are therefore essential to safeguard health, ensure food security and prevent degradation of this vital resource. / यद्यपि जल जलीय चक्र के माध्यम से नवीकरणीय है, बढ़ती जनसंख्या, बढ़ती कृषि और औद्योगिक माँग, भूजल का अति-दोहन और प्रदूषण ने स्वच्छ, उपयोगी जल को निरंतर दुर्लभ बना दिया है। इसलिए स्वास्थ्य की रक्षा, खाद्य सुरक्षा सुनिश्चित करने और इस महत्वपूर्ण संसाधन के निम्नीकरण को रोकने के लिए संरक्षण और प्रबंधन आवश्यक है।

Foundational laws & principles behind this chapter. Each one opens a full page — what it says, why it matters, five practice questions and the mistakes to avoid.