Water Resources

Why this chapter matters for UPSC: the chapter makes one argument in three moves. Water is renewable, yet regions run short of it because of how it is used, shared and polluted. Independent India answered with large multi-purpose dams, which then came under heavy criticism. Traditional and rooftop rainwater harvesting is offered as the alternative. Every one of these moves now has an official number behind it (the Central Water Commission's water budget, the Central Ground Water Board's 2025 assessment, the Jal Jeevan Mission's tap count), and a live legal dispute over the Indus.

Contemporary hook: on 31 August 2026 a Court of Arbitration at The Hague ruled unanimously that India's decision of 23 April 2025 to hold the Indus Waters Treaty "in abeyance" was "not permissible under the Treaty", and that the Treaty "remains fully in force". India did not take part in the hearing and rejected the award the same day: the Ministry of External Affairs said India has never recognised the court and that its decision to hold the Treaty in abeyance remains in force (MEA statement of 31 August 2026, as reported by Outlook).

🧠 First Principles — Read This First

NCERT starts from a puzzle. Three-fourths of the earth is covered with water, and freshwater is "continually being renewed and recharged through the hydrological cycle", so water is a renewable resource. Why, then, do countries and regions suffer from water scarcity?

The chapter's answer is that scarcity is mostly made by people. In NCERT's words, water scarcity "in most cases is caused by over-exploitation, excessive use and unequal access to water among different social groups". A region can have ample water and still be short of it, because its population is large, because its farms, factories and cities draw too much, or because the water it has is polluted.

Then come the two ways of managing water that the chapter compares:

1. Multi-purpose river projects: dams that store water for irrigation, power, flood control, water supply and navigation at once. NCERT presents both why they were built and why they are now opposed.
2. Rainwater harvesting: older, local systems (guls and kuls, khadins, johads, tankas, bamboo drip) and their modern rooftop versions in Tamil Nadu, Shillong and Gendathur.

One working rule for this page: India's water numbers come from different bodies measuring different things. The Central Water Commission (CWC) measures the total resource; the Central Ground Water Board (CGWB) measures groundwater recharge and extraction; the Jal Jeevan Mission counts tap connections. Quote each with its body and year.

PART 1 — Quick Reference

Table 1: India's water budget in official numbers

Source: Central Water Commission, Water Resource Estimation; Ministry of Jal Shakti, "Availability of Surface and Groundwater Resources", PIB 2223850, 5 February 2026; Ministry of Jal Shakti, "Per Capita Water Availability", PIB 2002726, 5 February 2024; CGWB, National Compilation on Dynamic Ground Water Resources of India, 2025.

The two CWC totals differ because they are two assessments; the per-capita figures were worked out on the 2019 one. The Ministry calls a region water stressed when annual per-capita availability is below 1,700 cubic metres and water scarce below 1,000. By its own threshold, India as a whole is already water stressed.

Table 2: The multi-purpose projects NCERT names

Source: NCERT, Contemporary India II, Reprint 2026-27, ch. 3, pp. 4-5; Odisha Hydro Power Corporation, Hirakud project; Supreme Court, Narmada Bachao Andolan v. Union of India, 18 October 2000; Yadav, Bansal and Pandey (Ministry of Earth Sciences), "Five decades of triggered earthquakes in Koyna-Warna Region", Earth-Science Reviews 162 (2016), seismo.gov.in.

Table 3: How NCERT classifies dams

Source: NCERT, Reprint 2026-27, ch. 3, p. 4.

NCERT's definition: a dam is "a barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or impoundment", and most dams have a spillway or weir over or through which water is meant to flow.

Table 4: Water harvesting systems in the chapter

Source: NCERT, Reprint 2026-27, ch. 3, pp. 7-10.

Table 5: Groundwater assessment units, CGWB 2025

Source: CGWB, National Compilation on Dynamic Ground Water Resources of India, 2025; Ministry of Jal Shakti, PIB 2220203, 29 January 2026.

The "stage of extraction" is extraction as a share of extractable recharge. At State level CGWB 2025 puts Haryana, Punjab and Rajasthan above 100%, Delhi between 90% and 100%, and Tamil Nadu and Puducherry between 70% and 90%.

PART 2 — Concepts & Narrative

Water scarcity: why a renewable resource runs short

NCERT asks the reader to drop the usual picture of scarcity, the Rajasthan desert and women carrying many matkas over long distances. Availability does vary over space and time with seasonal and annual rainfall, but scarcity "in most cases" comes from over-exploitation, excessive use and unequal access. The chapter then names the pressures one by one:

• Population and food. A large population needs water for domestic use and to grow more food, so water is over-exploited to expand irrigated areas for dry-season farming. NCERT is blunt: "Irrigated agriculture is the largest consumer of water." Farmers' own wells and tube-wells can lead to falling groundwater levels, affecting water availability and food security.
• Industry. Industries are heavy users of water and also need power, much of it from hydroelectricity.
• Cities. Multiplying urban centres add to water and energy demand; most housing societies in cities have their own groundwater pumping devices, and fragile water resources are being depleted.
• Quality. Even where there is enough water, it may be polluted by domestic and industrial wastes, chemicals, pesticides and fertilisers, making it hazardous to use.

A photo caption in the chapter makes the point: after a record 180 mm of overnight rain flooded Kolkata, a boy still had to collect drinking water.

Jal Jeevan Mission and Atal Jal

NCERT adds two government programmes to the chapter. The Jal Jeevan Mission aims to give every rural household "assured supply of potable piped water at a service level of 55 litres per capita per day regularly on long-term basis", by keeping tap connections functional (NCERT cites the Economic Survey 2020-21, p. 357). The Atal Bhujal Yojana (Atal Jal) works in 8,220 water-stressed gram panchayats of 229 blocks in 80 districts of seven States (Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan and Uttar Pradesh), which account for about 37% of India's water-stressed blocks. Its key aim, NCERT says, is to shift community attitudes "from the prevailing attitude of consumption to conservation and smart water management" (Ministry of Jal Shakti Annual Report 2022-23).

Multi-purpose river projects

Building water structures is old in India. NCERT's box on hydraulic structures (drawn from the Centre for Science and Environment's Dying Wisdom, 1997) lists them:

Dams were traditionally built to store river and rain water for irrigation. Today they also generate electricity, supply water to homes and industries, control floods, and serve recreation, inland navigation and fish breeding, so they are called multi-purpose projects: the uses of the stored water are integrated with one another. NCERT's two examples are the Bhakra-Nangal project in the Sutluj-Beas basin (hydel power and irrigation) and the Hirakud project in the Mahanadi basin (water conservation with flood control).

After Independence these projects were seen as the vehicle of development. Jawaharlal Nehru "proudly proclaimed the dams as the 'temples of modern India'", because they would join the growth of agriculture and the village economy with industrialisation and urban growth. NCERT sets beside this a Bhadu song from the Damodar valley, where people plead with the Damodar, "the river of sorrow", to reduce its floods.

The case against big dams

NCERT's current text gives the criticism in ecological terms:

• Damming affects a river's natural flow, causing poor sediment flow downstream and excessive sedimentation in the reservoir, which leaves rockier stream beds and poorer habitats for aquatic life.
• Dams fragment rivers, making it hard for aquatic fauna to migrate, especially for spawning.
• Reservoirs on floodplains submerge vegetation and soil, which decompose over time.
• "Ironically, the dams that were constructed to control floods have triggered floods due to sedimentation in the reservoir", and big dams have mostly failed to control floods in excessive rain.
• Floodplains are deprived of silt, a natural fertiliser, adding to land degradation.
• Multi-purpose projects induced earthquakes, caused water-borne diseases and pests, and led to pollution from excessive water use.
• Irrigation shifted farmers to water-intensive commercial crops, with consequences such as salinisation of the soil.

NCERT then turns to irrigation policy. The Pradhan Mantri Krishi Sinchayee Yojana aims to give every farm some means of protective irrigation. Its objectives, as NCERT lists them: expand the area under assured irrigation (har khet ko pani), improve on-farm water-use efficiency, spread water-saving technologies (per drop more crop) and introduce sustainable conservation practices.

Inter-State and international water disputes

NCERT's box on the Krishna-Godavari dispute: Karnataka and Andhra Pradesh objected to Maharashtra's plan to divert more water at Koyna for a multi-purpose project, since it would reduce downstream flow in their States and hurt agriculture and industry. The box ends with an exercise: "Make a list of inter-state water disputes."

Rainwater harvesting

"Many thought that given the disadvantages and rising resistance against the multi-purpose projects, water harvesting system was a viable alternative." NCERT credits ancient India with an extraordinary tradition here: people knew their rainfall regimes and soils and built ways to harvest rainwater, groundwater, river water and floodwater to suit local conditions (Table 4).

The tankas of the Thar. In Bikaner, Phalodi and Barmer almost every house traditionally had an underground tank, as large as a big room, built inside the house or courtyard and connected to the sloping roof by a pipe. The first spell of rain was not collected, because it cleaned the roof and pipes. The stored rainwater, palar pani, was considered the purest form of natural water and lasted till the next rain; some houses built cool underground rooms beside the tanka. Today the practice is declining in western Rajasthan because the perennial Indira Gandhi Canal supplies plenty of water, though some houses keep tankas because they do not like the taste of tap water.

Modern rooftop harvesting. NCERT's Fig. 3.3 shows two ways to recharge groundwater with roof water: through a hand pump, and through an abandoned dugwell, after filtering the water through sand and bricks.

• Tamil Nadu is "the first state in India which has made rooftop rainwater harvesting structure compulsory to all the houses across the state", with legal provisions to punish defaulters. The Centre for Science and Environment dates the rule to the Tamil Nadu Municipal Laws Ordinance of 19 July 2003, which made it mandatory for all buildings, public and private.
• Shillong faces acute water shortage although Cherapunjee and Mawsynram, 55 km away, "receive the highest rainfall in the world" (NCERT). Nearly every household has a rooftop system, which meets 15-25% of its needs.
• Gendathur, a remote village in Mysuru, Karnataka: about 200 households harvest roof water. With 1,000 mm of annual rain, 80% collection efficiency and about 10 fillings, each house collects about 50,000 litres a year.
• Meghalaya's bamboo drip irrigation: a 200-year-old system that taps streams and springs with bamboo pipes, carrying 18-20 litres over hundreds of metres down to 20-80 drops a minute at the plant.

What the pre-2023 edition said (removed in the rationalisation)

The 2023 rationalisation removed the social side of the dam debate from this chapter. These passages are not in the current book; they are summarised here because older guides still quote them, and because the current exercise still treats "large scale displacements and loss of livelihood" as the case against multi-purpose projects.

• Movements: dams "have also been the cause of many new environmental movements like the 'Narmada Bachao Andolan' and the 'Tehri Dam Andolan'". Resistance was "primarily" due to the large-scale displacement of local communities, who gave up land, livelihood and access to resources "for the greater good of the nation".
• Who benefits: the old text asked whether the landless in a village really gain from such a project, and said irrigation had increased "the social gap between the richer landowners and the landless poor".
• Conflicts over the same water: Sabarmati-basin farmers in Gujarat "almost caused a riot" over the higher priority given to urban water supply in droughts; inter-State disputes arose over sharing costs and benefits.
• The NBA box: the Narmada Bachao Andolan was described as an NGO that mobilised tribal people, farmers, environmentalists and human rights activists against the Sardar Sarovar Dam; it began with the trees that would be submerged and later refocused on full rehabilitation for the oustees.
• The Rihand quote: survivors displaced by the Rihand dam asked, "Are we the only ones chosen to make sacrifices for the nation?" (S. Sharma, quoted in A. Baviskar, In the Belly of the River, 1995).

For the movement's later history, the Narmada Bachao Andolan received the Right Livelihood Award in 1991. In the Right Livelihood Foundation's account, the movement pressed the World Bank, which supported the dam with a US$ 450 million loan, to review the project.

PART 3 — UPSC Integration

Frames for Mains Answers

• Scarcity is mostly man-made: start from NCERT's three causes (over-exploitation, excessive use, unequal access) and add quality. Support with CGWB 2025: 87% of groundwater goes to irrigation, 730 units over-exploited, three States above 100%.
• Dams, both ledgers: benefits (irrigation, power, flood control, drought-proofing as in the Sardar Sarovar command) against NCERT's ecological costs (sediment, fragmentation, triggered floods and earthquakes, salinisation) and the displacement argument of the older edition. Close on dam safety law and rehabilitation.
• Small is not only old: tankas, johads and kuls show local fit; Tamil Nadu, Shillong and Gendathur show the modern version; Tarun Bharat Sangh shows revival at scale. Pair them with demand-side reform (per drop more crop).
• Water across boundaries: inter-State disputes (Article 262, tribunals, the lapsed 2019 Bill) and international treaties (Indus in abeyance and the 2026 award; Ganga treaty due in December 2026).

Exam Strategy

Prelims fact-traps:

• Bhakra-Nangal is in the Sutluj-Beas basin; Hirakud is on the Mahanadi; Sardar Sarovar is on the Narmada in Gujarat but serves four States.
• Hirakud's 25.8 km is the main dam (4.8 km) plus dykes (21 km).
• Khadins are Jaisalmer's; johads are elsewhere in Rajasthan; tankas are Bikaner, Phalodi and Barmer; guls/kuls are Western Himalayan.
• Tamil Nadu was the first State to make rooftop harvesting compulsory for all houses.
• Water is Entry 17, State List, subject to Entry 56, Union List; disputes go under Article 262.
• Dam Safety Act, 2021: specified dams above 15 m (or 10-15 m with conditions); in force 30 December 2021.
• CGWB categories: safe up to 70%, semi-critical 70-90%, critical 90-100%, over-exploited above 100%.

Mains answers:

• Scarcity: give causes plus data; quote CWC and CGWB with years.
• Irrigation: cover the demand side too, with micro-irrigation, PMKSY and groundwater governance (Atal Jal).
• Treaties: state the current status with dates, the Indus abeyance (23 April 2025) and the award (31 August 2026).

Practice Questions

Practice (UPSC-pattern, not past papers). Questions 1 and 2 are NCERT's own exercise MCQs.

1. Which one of the following statements is not an argument in favour of multi-purpose river projects?
(a) Multi-purpose projects bring water to those areas which suffer from water scarcity.
(b) Multi-purpose projects by regulating water flow helps to control floods.
(c) Multi-purpose projects lead to large scale displacements and loss of livelihood.
(d) Multi-purpose projects generate electricity for our industries and our homes.

2. Classify each situation as "suffering from water scarcity" or "not suffering from water scarcity": (a) region with high annual rainfall; (b) region having high annual rainfall and large population; (c) region having high annual rainfall but water is highly polluted; (d) region having low rainfall and low population.
A reasoned answer from the chapter: (a) not suffering; (b) can suffer, because a large population raises demand; (c) suffering, because polluted water is unusable; (d) not necessarily, because low demand can match low supply. The point NCERT is making is that rainfall alone does not decide scarcity.

3. With reference to the Central Ground Water Board's 2025 assessment, consider the following statements:
1. More than half of India's annual extractable groundwater is being extracted.
2. Agriculture accounts for less than three-fourths of groundwater extraction.
3. Haryana, Punjab and Rajasthan each extract more groundwater than their annual extractable resource.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

4. Consider the following statements:
1. Water supplies and irrigation are listed in the State List, subject to an entry in the Union List.
2. Article 262 allows Parliament to bar the Supreme Court from jurisdiction over inter-State river water disputes.
3. The Dam Safety Act, 2021 applies to every dam irrespective of its height.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

5. Consider the following pairs (system : region, as in NCERT):
1. Khadins : Jaisalmer
2. Kuls : Western Himalaya
3. Tankas : Bengal flood plains
How many of the pairs given above are correctly matched?
(a) Only one
(b) Only two
(c) All three
(d) None

6. NCERT Ex. 1 (iii): identify the mistakes and rewrite correctly.

• (a) "Multiplying urban centres with large and dense populations and urban lifestyles have helped in proper utilisation of water resources." Correct: they have added to water and energy demand and led to over-exploitation of groundwater.
• (b) "Regulating and damming of rivers does not affect the river's natural flow and its sediment flow." Correct: it affects both, causing poor sediment flow downstream and sedimentation in the reservoir.
• (c) "Today in Rajasthan, the practice of rooftop rainwater harvesting has gained popularity despite high water availability due to the Indira Gandhi Canal." Correct: in western Rajasthan the practice is declining because the canal supplies plenty of water.

Short answers (NCERT Ex. 2, about 30 words):

• Explain how water becomes a renewable resource.
• What is water scarcity and what are its main causes?
• Compare the advantages and disadvantages of multi-purpose river projects.

Long answers (NCERT Ex. 3, about 120 words):

• Discuss how rainwater harvesting in semi-arid regions of Rajasthan is carried out.
• Describe how modern adaptations of traditional rainwater harvesting methods are being carried out to conserve and store water.

Mains practice (150 words): "India's water problem is less a shortage of water than a failure to manage it." Examine with reference to groundwater use and rainwater harvesting.

📦 Revision Capsule

Sources

• NCERT, Contemporary India II, Class X, ch. 3 "Water Resources", Reprint 2026-27 — jess103.pdf; 2020-21 edition for the removed passages (the whole book as one zip file, as archived on 9 October 2021: Wayback Machine).
• Central Water Commission, Water Resource Estimation (2019 assessment) — cwc.gov.in.
• Ministry of Jal Shakti, "Availability of Surface and Groundwater Resources", 5 February 2026 — PIB 2223850.
• Ministry of Jal Shakti, "Per Capita Water Availability", 5 February 2024 — PIB 2002726.
• Central Ground Water Board, National Compilation on Dynamic Ground Water Resources of India, 2025 — cgwb.gov.in; Ministry of Jal Shakti, 29 January 2026 — PIB 2220203.
• NITI Aayog, Composite Water Management Index (2018) — CWMI report.
• Prime Minister's Office, Cabinet approves extension of the Jal Jeevan Mission to December 2028, 10 March 2026 — pmindia.gov.in.
• Ministry of Jal Shakti, Year End Review 2025, 30 December 2025 — PIB 2209732.
• Odisha Hydro Power Corporation, Hirakud Hydro Electric Project — ohpcltd.com.
• A. Yadav, B. K. Bansal, A. P. Pandey (Ministry of Earth Sciences), "Five decades of triggered earthquakes in Koyna-Warna Region, western India – A review", Earth-Science Reviews 162 (2016) 433-450 — seismo.gov.in; USGS, M 6.5 Koyna event of 10 December 1967 (ISC-GEM) — earthquake.usgs.gov.
• The Dam Safety Act, 2021 (No. 41 of 2021) — Act text, Water Resources Department, Maharashtra; Central Water Commission, Dam Safety Act 2021 — cwc.gov.in; PRS Legislative Research, The Dam Safety Bill, 2019 — prsindia.org.
• Legislative Department, Constitution of India (Article 262; Seventh Schedule, List I entry 56, List II entry 17) — legislative.gov.in.
• PRS Legislative Research, The Inter-State River Water Disputes (Amendment) Bill, 2019 — prsindia.org; Ministry of Jal Shakti letter of 11 November 2024 on the Bill's lapse — PDF; Cabinet approves the Bill, 10 July 2019 — PIB 1578194.
• Supreme Court of India, Narmada Bachao Andolan v. Union of India, 18 October 2000 — Indian Kanoon.
• Prime Minister's Office, "PM dedicates Sardar Sarovar Dam to the nation", 17 September 2017 — PIB 1503142.
• Right Livelihood Foundation, Medha Patkar and Baba Amte / Narmada Bachao Andolan (1991) — rightlivelihood.org.
• Permanent Court of Arbitration, press release on the award in the Indus Waters Western Rivers arbitration, The Hague, 31 August 2026 — PDF.
• Ministry of External Affairs statement on the Court of Arbitration award, 31 August 2026, as reported by Outlook, 31 August 2026 — outlookindia.com.
• Outlook, "Ganga Water Treaty explained" — outlookindia.com; Daily Observer (Dhaka), "Ganges Treaty renewal: 'Uncertainty' of water sharing", 1 September 2026 — observerbd.com.
• Centre for Science and Environment, Legislation on rainwater harvesting — cseindia.org.
• Tarun Bharat Sangh, About — tarunbharatsangh.in; Ramon Magsaysay Award Foundation, Rajendra Singh (2001) — rmaward.asia.