Water Resources

Why this chapter matters for UPSC: Water is India's most critical natural resource challenge. UPSC tests water geography in GS1 (river systems, water availability, inter-basin transfer), GS2 (interstate water disputes — Cauvery, Krishna, Ravi-Beas), and GS3 (irrigation policy, water pricing, groundwater regulation, rainwater harvesting, watershed management). India's water crisis — falling groundwater tables, pollution, and inter-state conflicts — makes this a perennially relevant policy topic.

Contemporary hook: India is home to 18% of the world's population but has only 4% of the world's freshwater resources. The NITI Aayog's Composite Water Management Index (2018) warned that 21 major cities (including Delhi, Bengaluru, Chennai, Hyderabad) could run out of groundwater by 2020 — and while the worst predictions haven't fully materialised, the trajectory is deeply concerning. Chennai's 2019 "Day Zero" water crisis — when all four major reservoirs ran dry simultaneously — was a warning shot.

PART 1 — Quick Reference Tables

India's Water Availability

Major River Systems: UPSC Data Points

Water Use Distribution in India

Note: Agriculture's 89% water use makes it the critical target for water efficiency improvements

Major Interstate Water Disputes

PART 2 — Detailed Notes

Surface Water Resources

India's surface water is unevenly distributed — the Ganga-Brahmaputra-Meghna system in the north and east accounts for ~60% of India's river flow, while peninsular rivers (Karnataka, AP, Tamil Nadu) are monsoon-dependent and often run dry in summer.

River water availability vs demand:

• Water-surplus basins: Brahmaputra, Ganga, Mahanadi, Godavari — more water than current local demand
• Water-deficit basins: Cauvery, Krishna, Luni, rivers of Rajasthan — demand exceeds local availability

This geographic mismatch is the rationale for the National River Linking Project (NRLP).

Groundwater: India's Hidden Crisis

Groundwater provides:

• ~63% of irrigation water (tubewells)
• ~85% of rural drinking water
• ~50% of urban water supply

Overextraction: India extracts more groundwater annually than any other country — ~250 BCM/year, vs global recommended sustainable rate of ~180 BCM. In Punjab and Haryana, water tables are falling 0.5–1 metre per year due to paddy cultivation (paddy requires 1,200–1,500 litres per kg vs wheat's 400–800 litres/kg).

Regulated but dysfunctional: India has no comprehensive national groundwater regulation. The Draft National Groundwater Management and Regulation Act has been pending since 2017. The Atal Bhujal Yojana (2019) is a World Bank-funded groundwater management scheme for water-stressed blocks in 7 states.

💡 Explainer: National River Linking Project (NRLP)

The NRLP proposes to transfer water from "surplus" rivers (Ganga, Brahmaputra, Mahanadi, Godavari) to "deficit" rivers (Cauvery, Krishna, rivers of Rajasthan) through a network of canals, tunnels, and reservoirs.

Scale: ~30 river links; ~15,000 km of canals; estimated cost ₹5.5 lakh crore (at 2002 prices — would be many times higher today).

Arguments for NRLP:

• Would provide irrigation to 34 million hectares (additional)
• Generate 34,000 MW hydropower
• Reduce flood damage in surplus basins (Brahmaputra floods)
• Address water deficit in peninsular India and Rajasthan
• Supreme Court (2012) directed government to prepare a "comprehensive study" (T.N. Godavarman vs Union of India context)

Arguments against NRLP:

• Massive displacement — millions of people in river flood plains and wetlands
• Ecological disruption — riverine ecosystems, mangroves, fisheries depend on natural flow
• "Surplus river" concept is flawed — Brahmaputra floods are seasonal; not permanent surplus
• India-Bangladesh relations — Bangladesh objected to Brahmaputra-Ganga link because Brahmaputra feeds Bangladesh's irrigation (Farakka already contested)
• Astronomical cost; long implementation timeline; corruption risk
• Opportunity cost — same money could build 100 million water-harvesting structures

Status: Only Ken-Betwa Link Project (Madhya Pradesh-UP; finalised 2021, construction ongoing) is being implemented among NRLP's 30 links. The rest remain on paper.

Interstate Water Disputes

Cauvery Dispute: The Cauvery basin covers Karnataka (~34%) and Tamil Nadu (~43%) — two states whose agricultural calendars depend on the river. Karnataka built reservoirs (KRS Dam — Krishnaraja Sagar) for irrigation in Mysuru plateau; Tamil Nadu depends on Mettur Dam (Stanley Reservoir) for Cauvery delta (Thanjavur) rice farming.

Core conflict: Karnataka wants more water for Bengaluru's growing urban demand and irrigation expansion; Tamil Nadu argues it has prior rights (historical agreements from 1892 and 1924, British-era agreements between Mysore and Madras).

Current status: Cauvery Water Management Authority (CWMA, 2018) implements the Supreme Court's 2018 award allocating 177.25 TMC to TN, 284.75 TMC to Karnataka (increased from Tribunal's 270 TMC by 14.75 TMC — SC awarded extra for Bengaluru's drinking water needs).

SYL Canal (Sutlej-Yamuna Link): Punjab's 214 km canal linking Sutlej to Yamuna, to carry Ravi-Beas river water to Haryana and Rajasthan. Canal dug in Haryana but not completed on Punjab's side.

Punjab's position: Punjab has no water to spare; Green Revolution has already depleted groundwater; Haryana's share was based on outdated river flow data. Haryana's position: Punjab is illegally denying its constitutionally allocated share. Supreme Court: Directed Punjab to complete the canal; Punjab's legislature enacted a law terminating water agreements — SC struck it down. Dispute remains unresolved.

Irrigation in India

India has the largest irrigated area in the world (~68 million hectares net irrigated; ~97 million ha gross irrigated). Irrigation sources:

Irrigation efficiency problem: India's average irrigation efficiency is ~35–40% — meaning 60-65% of water diverted for irrigation is lost to evaporation, seepage, and runoff. Drip and sprinkler irrigation (micro-irrigation) achieves 70–90% efficiency.

Pradhan Mantri Krishi Sinchayee Yojana (PMKSY): Launched 2015; tagline "Har Khet Ko Paani, More Crop Per Drop." Aims to expand irrigation coverage, improve water use efficiency, accelerate irrigation project completion.

Accelerated Irrigation Benefits Programme (AIBP): Completes long-pending irrigation projects; funds from central government.

📌 Key Fact: Virtual Water and Food Trade

"Virtual water" concept (John Allan, 1993) calculates the water embedded in traded goods. India exporting rice and sugar is essentially exporting water from water-stressed regions. India exports ~100 BCM of virtual water annually through agricultural exports — in a country with water scarcity. This raises the policy question: should water-intensive crops be grown in water-deficit regions?

Rainwater Harvesting and Traditional Water Management

Traditional systems:

• Johads (Rajasthan) — earthen check dams storing rainwater; Tarun Bharat Sangh's work in Alwar district reviving them
• Stepwells (Vav/Baoli) — Rani ki Vav (Patan, Gujarat — UNESCO World Heritage Site); Chand Baori (Abhaneri, Rajasthan)
• Tank irrigation — South India; thousands of cascade tanks (Odisha, Tamil Nadu, Karnataka); many now derelict
• Zabo (Nagaland) — "impounding run-off" system; contour trenches collect rainwater in paddy fields
• Bamboo drip irrigation (Meghalaya) — traditional tribal system
• Pyne (Bihar) — local canal/diversion systems from hill streams

Modern rainwater harvesting:

• Rooftop rainwater harvesting mandated in many urban building codes (Tamil Nadu, Rajasthan)
• Percolation ponds, check dams for groundwater recharge
• Watershed development — treating a micro-watershed (500–2,000 hectares) as a unit; check dams, contour bunding, vegetative bunds, farm ponds

🎯 UPSC Connect: Watershed Management

India's watershed management programmes (IWMP, NABARD's WADI programme) have shown that treatment of degraded watersheds can:

• Increase groundwater recharge 2–3 fold
• Reduce soil erosion 50–70%
• Increase crop productivity 30–50%
• Reduce rural poverty (more stable water access → better harvests → higher incomes)

Ralegan Siddhi (Maharashtra) — transformed by Anna Hazare's community watershed work in the 1970s-80s — is the most celebrated case: a dryland drought-prone village transformed into a water-secure, prosperous community through check dams, contour trenches, and ban on tree-cutting.

🔗 Beyond the Book: National Water Policy

India's National Water Policy 2012 (a revision of 2002 policy) establishes priorities for water allocation:

1. Drinking water
2. Irrigation for subsistence/food security
3. Other agricultural uses
4. Industrial use
5. Navigation and other uses

Problem: The policy is a statement of principles, not enforceable law. India lacks a National Water Framework Law. Draft frameworks have been proposed but not enacted. The result: each state manages its own water allocation; interstate conflicts; groundwater is a free good for farmers (exploited without charge in most states).

PART 3 — Frameworks and Analysis

Water Conflict Anatomy: Understanding Interstate Disputes

For any interstate water dispute question, cover:

1. Geographic reality — which states share the basin; water flow patterns
2. Historical agreements — pre-independence; colonial-era; earlier tribunal awards
3. Development asymmetry — which state built more infrastructure (dams, canals) vs which has prior-use rights
4. Social/agricultural dependence — which farming communities depend on the river; what crops; what political mobilisation
5. Legal framework — Inter-State River Water Disputes Act (1956); Role of Tribunal; Supreme Court's role
6. Current status — tribunal award; CWMA; pending completion

Three Strategies for Water Security

Exam Strategy

For Prelims: India's annual utilisable water (~1,123 BCM), irrigation's share (~90%), groundwater share of irrigation (~63%). River facts (Ganga length, Brahmaputra basin area). Know Cauvery and SYL disputes. Know Atal Bhujal Yojana, PMKSY.

For Mains GS1: River system facts; water availability vs demand geography; NRLP (for and against). Interstate disputes — Cauvery structure: 4 parties, history, CWMA, SC verdict.

For Mains GS3: Irrigation efficiency (35% vs 70–90% drip); groundwater crisis (Punjab case — Green Revolution link); watershed management (Ralegan Siddhi, Tarun Bharat Sangh); PMKSY; virtual water concept.

For Mains GS2: Interstate water disputes — constitutional provision (Entry 17, State List; Article 262 — Inter-State River Water Disputes Act); institutional mechanism (Tribunal, CWMA).

Practice Questions

1. UPSC Mains GS1 2019: "Explain the geographic basis of interstate river water disputes in India. How does the Inter-State River Water Disputes Act address these?" (Core water dispute question)

2. UPSC Mains GS3 2021: "India's groundwater is being exploited unsustainably. Analyse the causes and suggest a comprehensive policy response." (Groundwater crisis)

3. UPSC Mains GS3 2018: "Critically evaluate the National River Linking Project. Is it the solution to India's water woes?" (NRLP debate)

4. UPSC Mains GS3 2022: "Traditional water conservation practices have proven more sustainable than large-scale dam-based irrigation. Discuss with examples." (Traditional systems + watershed)