India's Water Availability — Key Statistics

India receives an average annual precipitation of approximately 4,000 BCM (Billion Cubic Metres). However, much of this is lost to evapotranspiration, runoff into the sea, and seasonal flooding.

According to the Central Water Commission (CWC) Assessment of Water Resources of India, the average annual water availability (1985–2023) is estimated at approximately 2,116 BCM.

The total utilisable water with conventional approach is 1,137 BCM, comprising:

  • Surface water: 690 BCM (utilisable)
  • Groundwater: 447 BCM (replenishable and utilisable)

Per Capita Water Availability (Declining Trend)

Year Per Capita Availability (m³/year)
1951 ~5,177
2001 ~1,816
2011 ~1,545
Projected 2025 ~1,367

Water stress threshold (UN): 1,700 m³/capita/year — India is approaching water-stressed status nationally and several states (Punjab, Haryana, Rajasthan) are already severely water-stressed.

Irrigation accounts for approximately 78% of India's total water use, making it the dominant sector.

Irrigation in India

India has one of the largest irrigated areas in the world. Approximately 54% of net sown area is under irrigation.

Types of Irrigation

Type Share of Irrigated Area Key States Features
Tube well / Borewell (Groundwater) Largest share — ~60%+ Punjab, Haryana, UP, Maharashtra Flexible, responsive; major cause of groundwater depletion
Canal irrigation ~25–30% UP, Rajasthan, Haryana, Punjab, Bihar Best for flat terrain; high capital cost; waterlogging risk
Tank irrigation ~5–6% Tamil Nadu, AP, Telangana, Karnataka Traditional; historically Chola tanks; declining due to neglect
Other wells (open wells) Declining Maharashtra, Gujarat Less efficient than tube wells

Drip and sprinkler irrigation are micro-irrigation methods being promoted under Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) — "Har Khet Ko Pani, More Crop Per Drop."

  • Drip irrigation (trickle irrigation) — delivers water directly to root zone; ideal for horticulture, vineyards; major uptake in Maharashtra, Karnataka, Gujarat.
  • Sprinkler irrigation — simulates rainfall; used for uneven terrain and field crops.

Major Irrigation Projects

Project River State(s) Key Facts
Bhakra-Nangal Sutlej Punjab/Haryana/HP Gobind Sagar reservoir; Nehru called it a "temple of modern India"; dam height 226m
Hirakud Dam Mahanadi Odisha World's longest earthen dam (25.8 km including dykes); first major multipurpose project post-independence; largest artificial lake in India
Sardar Sarovar Project (SSP) Narmada Gujarat, MP, Rajasthan, Maharashtra Controversial displacement (Narmada Bachao Andolan); dam height raised multiple times; reservoir — Sardar Sarovar
Tehri Dam Bhagirathi + Bhilangana Uttarakhand One of world's tallest dams (~261m); concerns about seismicity; Tehri township submerged
Nagarjuna Sagar Krishna AP/Telangana One of India's largest masonry dams
Indira Gandhi Canal Sutlej/Beas (Harike headworks) Rajasthan Transforms Thar Desert areas; environmental concerns (waterlogging, salinity)

Groundwater in India

India is the world's largest user of groundwater, extracting approximately 245 BCM per year (as per CGWB 2024 assessment) — more than the USA and China combined.

Groundwater Depletion — States Most Affected

State Status Main Cause
Punjab Critically over-exploited Paddy cultivation with free power subsidies
Haryana Over-exploited Green Revolution crops; canal seepage inadequacy
Rajasthan Over-exploited in western parts Arid climate; high agricultural demand
Tamil Nadu Over-exploited in several districts Rapid industrialisation + agriculture
Delhi NCR Declining rapidly Urban extraction; inadequate recharge

CGWB (Central Ground Water Board) — premier national body under Ministry of Jal Shakti for groundwater assessment, management and regulation.

Atal Bhujal Yojana (Atal Jal)

  • Launched: 25 December 2019 (95th birth anniversary of Atal Bihari Vajpayee).
  • Implemented in 7 states: Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan, Uttar Pradesh.
  • Focus: community-led, participatory groundwater management in water-stressed areas.
  • Covers 8,562 Gram Panchayats across 80 districts.
  • Funded by World Bank (50%) and Government of India (50%).
  • Extended until March 2026.
  • Key innovation: Water Security Plans prepared at Gram Panchayat level.

Inter-State River Disputes

Constitutional framework: Article 262 of the Constitution empowers Parliament to provide for adjudication of disputes relating to use, distribution or control of inter-state rivers. The Inter-State River Water Disputes (ISRWD) Act, 1956 establishes the mechanism for Tribunals.

Key Tribunals and Awards

Dispute States Tribunal Key Award
Cauvery (Kaveri) Karnataka, Tamil Nadu, Kerala, Puducherry Cauvery Water Disputes Tribunal Final award (Feb 2007): Tamil Nadu — 404.25 TMC, Karnataka — 284.75 TMC, Kerala — 30 TMC, Puducherry — 7 TMC; Supreme Court upheld in Feb 2018; Cauvery Water Management Authority constituted June 2018
Krishna AP, Telangana, Maharashtra, Karnataka Krishna Water Disputes Tribunal I (1969) and II Bifurcation of AP/Telangana made re-adjudication necessary
Narmada MP, Gujarat, Rajasthan, Maharashtra Narmada Water Disputes Tribunal Final Award 1979 — SSP dam height fixed; disputes over raising height continued
Ravi-Beas Punjab, Haryana, Rajasthan Eradi Tribunal (1986) Haryana awarded 3.5 MAF; Sutlej-Yamuna Link (SYL) canal controversy — Punjab legislature cancelled agreement; SC ordered construction; politically unresolved
Mahadayi Goa, Karnataka, Maharashtra Mahadayi Water Disputes Tribunal Karnataka seeks diversion for Malaprabha basin; Goa opposes; award 2018

New ISRWD (Amendment) Act 2019 — inter-state river disputes to be adjudicated by a single permanent tribunal with benches, replacing the system of individual tribunals.

International Water Treaties

Indus Waters Treaty (IWT), 1960

  • Signed at Karachi on 19 September 1960 by Indian PM Jawaharlal Nehru and Pakistani President Ayub Khan, brokered by the World Bank.
  • Allocation:
    • Eastern rivers (Ravi, Beas, Sutlej) → India (unrestricted use)
    • Western rivers (Indus, Jhelum, Chenab) → Pakistan (unrestricted use; India has limited run-of-river use rights)
  • India uses ~20% of total Indus system water; Pakistan ~80%.
  • A Permanent Indus Commission (one Commissioner from each side) meets annually.
  • The Treaty survived two wars (1965, 1971) — considered one of the world's most successful water-sharing agreements.
  • India suspended the IWT in May 2025 following the Pahalgam terror attack — a significant diplomatic and legal development.

Ganga Waters Treaty, 1996 (India–Bangladesh)

  • Governs sharing of Ganga waters at Farakka — India built Farakka Barrage (1975) to divert flows to Kolkata port (Hooghly).
  • Treaty signed in December 1996 for 30 years; allocates minimum guaranteed flows to Bangladesh during dry season (January–May).

Mahakali Treaty, 1996 (India–Nepal)

  • Governs joint development of the Mahakali River (Sharda in India), including Sarada Barrage, Tanakpur Barrage and the proposed Pancheshwar Multipurpose Project.

Water Policy Framework

National Water Policy 2012

Key principles:

  • Water is a national resource; state governments are trustees.
  • Priority order: drinking water → food security → ecology → agriculture → industry
  • River basin as the unit of planning.
  • Demand management and pricing reforms essential.
  • Promotion of water use efficiency and recycling.
  • Recognition of ecological flows in rivers.

A revised National Water Policy was under preparation as of 2025.

Jal Jeevan Mission (JJM)

  • Launched August 2019 — aims to provide piped tap water (Functional Household Tap Connection — FHTC) to every rural household.
  • Original target: 100% coverage by 2024 — target extended to 2028.
  • Progress (as of February 2025): ~15.44 crore households (approximately 79.74% of rural households) have tap connections, up from just 17% (3.23 crore households) in 2019.
  • Budget 2025-26 allocation: ₹67,000 crore.
  • Challenge: while connections exist, functional water supply (adequate, regular, safe) is achieved in only ~75% of connected households.

Key Concepts

Concept Explanation
Virtual Water Trade When India exports water-intensive products (rice, sugar), it "exports" the water embedded in them — a net drain in a water-scarce country
Water Footprint Total volume of freshwater used to produce a good/service
Waterlogging Excess irrigation raises water table; soil becomes saturated; roots suffocate — a major issue in canal-irrigated Punjab/Haryana
Salinisation Evaporation of irrigation water leaves salts behind; renders soil infertile — the Indira Gandhi Canal belt faces this
Ecological flows Minimum river flow needed to maintain river ecosystem health

Exam Strategy

  • Water availability figures: utilisable 1,137 BCM (690 surface + 447 groundwater) — cite CWC data, not just approximations.
  • Hirakud = longest earthen dam (world); Tehri = one of world's tallest dams. These are commonly mixed up in prelims.
  • Atal Bhujal Yojana covers 7 states (not 5 as sometimes stated) — verify: Gujarat, Haryana, Karnataka, MP, Maharashtra, Rajasthan, UP.
  • Indus Waters Treaty rivers: Eastern (Ravi, Beas, Sutlej) → India; Western (Indus, Jhelum, Chenab) → Pakistan. A classic prelims question.
  • Cauvery award figures: Tamil Nadu 404.25 TMC, Karnataka 284.75 TMC — these specific numbers have been tested.
  • Article 262 + ISRWD Act 1956 for constitutional basis of river disputes. Know the 2019 amendment (single permanent tribunal).
  • For Mains GS3 (Environment/Agriculture links): discuss groundwater depletion + MSP policy incentivising water-intensive crops (paddy in Punjab) — a classic integrated question.

Previous Year Questions (PYQs)

Prelims

  • (2021) Consider the following rivers: Barak, Lohit, Subansiri. Which of these has its source within India? (tests knowledge of river origins)
  • (2019) With reference to Indus Waters Treaty, consider the following statements — identify correct ones (eastern/western river allocation frequently tested)
  • (2018) Which of the following statements about Hirakud Dam is correct? (location, river — Mahanadi, longest earthen dam)
  • (2020) Consider the following: 1. SYL Canal 2. Cauvery Water Management Authority — associated with inter-state water disputes
  • (2016) With reference to National Water Policy, identify correct statements (priority order, demand management)

Mains

  • (2019, GS3) Water is essential for food security. Discuss the challenges of groundwater depletion in India and suggest sustainable management strategies. (15 marks)
  • (2021, GS1) Discuss the factors responsible for inter-state water disputes in India. With reference to any two disputes, examine the resolution mechanisms. (15 marks)
  • (2018, GS2) The Indus Waters Treaty has survived several Indo-Pakistani crises. Examine its significance as a model of transboundary water sharing and its recent challenges. (15 marks)
  • (2022, GS3) "India's irrigation paradox — expanding coverage but declining efficiency." Critically analyse with reference to canal, groundwater and micro-irrigation systems. (15 marks)