Indus Water Treaty (IWT) UPSC Notes: History, Disputes, and India’s Strategic Stand

“Water is the new oil of the 21st century.” — Ismail Serageldin

Few agreements in the world have shaped geopolitics. One such example is the Indus Water Treaty (IWT) signed in 1960. It lays down how India and Pakistan share the water of the Indus, Jhelum, Chenab, Ravi, Beas, and Sutlej rivers. 

For UPSC aspirants, the IWT remains a high-yield topic under GS Paper II (International Relations) and GS Paper I (Geography – river systems). Let’s study this topic in detail!

The Indus Waters Treaty is an international water-sharing agreement between India and Pakistan that governs the distribution and usage of water from the Indus River system and its six major tributaries.

It was signed on September 19, 1960, following nine years of negotiations brokered by the World Bank. It stands as one of the world's most successful and durable international water treaties.

• The World Bank was a mediator and also a signatory to the treaty, making it a three-party agreement.
• The treaty divides six major rivers of the Indus system into two categories: Eastern Rivers (allocated to India) and Western Rivers (allocated to Pakistan).
• India receives approximately 20% of the total water from the Indus basin, while Pakistan receives 80%.
• The treaty allows India specific non-consumptive uses (like hydropower generation) on western rivers, while Pakistan has unrestricted use of western rivers.
• Despite the 1965 Indo-Pak War, the 1971 Bangladesh War, and the 1999 Kargil War Conflict, water flows under the treaty were never interrupted until April 2025.

Also read: Mahanadi River Inter-State Water Dispute

The Indus Waters Treaty began after India and Pakistan’s independence, when both countries saw the need to cooperate over shared rivers.

• The partition of British India in 1947 suddenly split the unified Indus River basin between India and Pakistan, creating immediate water conflict.
• Two critical irrigation headworks - Madhopur (Ravi River) and Ferozepur (Sutlej River) fell within Indian territory after partition, leaving Pakistan vulnerable.
• Bilateral negotiations (1948-1951) failed because both nations had competing claims and no agreement on a permanent division formula.
• Pakistan escalated the dispute to the United Nations in 1951, complaining that India was unfairly controlling the water supply.
• World Bank President Eugene Black proposed mediation in March 1952; both India and Pakistan accepted.
• The World Bank proposed in February 1954 to partition the rivers rather than share them: Eastern Rivers to India (Ravi, Beas, Sutlej) and Western Rivers to Pakistan (Indus, Jhelum, Chenab).
• By May 1959, World Bank Vice Presidents visited PM Nehru and President Ayub Khan to push for a final settlement.
• The Indus Waters Treaty was signed on September 19, 1960, in Karachi by Jawaharlal Nehru, Ayub Khan, and W.A.B. Iliff (World Bank VP).
• The treaty established the Permanent Indus Commission (PIC) with annual meetings to oversee implementation and resolve technical issues.
• The treaty survived 4 India-Pakistan wars (1965, 1971, 1999, 2001-02).

On April 23, 2025, India suspended the treaty following the Pahalgam terror attack, ending 65 years of continuous cooperation.

Must cover: India-Pakistan Relations UPSC Notes: History, Wars, Indus Water Treaty

The Indus River system is divided into two groups, ensuring that both countries get what they need from the basins flowing through their territories.

Eastern Rivers Allocated to India

The Eastern Rivers (also called the Three Eastern Rivers or TER) are located primarily in Indian territory and flow through Punjab, Himachal Pradesh, Haryana, and Rajasthan before entering Pakistan.

1. Sutlej (Satluj) River:

• Length: 1,450 kilometres
• Origin: Mansarovar Lake in Tibet, enters India through Shipki La Pass in Himachal Pradesh
• Tributaries: Spiti River, Sunsa River
• Key Projects: Bhakra Dam (1,325 MW), Pandoh Dam, Pong Dam (1,050 MW capacity)

2. Beas River:

• Length: 470 kilometres
• Origin: Beas Kund near Rohtang Pass in Himachal Pradesh (at 4,000 meters elevation)
• Tributaries: Sutej joins the Beas
• Key Projects: Pong Dam (also known as Maharana Pratap Sagar), Pandoh Dam

3. Ravi River:

• Length: 725 kilometres
• Origin: Rohtang Pass in Himachal Pradesh's Kullu Hills
• Tributaries: Ujh River, Basantar River
• Key Projects: Thein Dam (Ranjit Sagar), Ujh Multipurpose Project

Western Rivers Allocated to Pakistan

The Western Rivers (also called the Three Western Rivers or TWR) are allocated to Pakistan for unrestricted use, but India retains specific limited rights for non-consumptive purposes.

1. Indus River:

• Total: 3,180 kilometres (the longest river in the Indian subcontinent)
• Origin: Mansarovar Glacier near Mount Kailash in Tibet, marked as "Sênggê Kanbab" or "Lion's Mouth"
• Tributaries: Zaskar, Suru, Shyok, Gilgit, Hunza (right-bank tributaries); Zanskar (left-bank)

2. Jhelum River:

• Length: 725 kilometres
• Origin: Verinag Spring in Pir Panjal Range (Anantnag district, Kashmir)
• Tributaries: Kishanganga (Neelum) River, Kunhar River, Poonch River
• Key Projects: Mangla Dam (Pakistan, 1,000 MW), Uri Hydroelectric Project (480 MW, India)

3. Chenab River:

• Length: 960 kilometres
• Origin: Lahaul and Spiti district of Himachal Pradesh (Bara Lacha Pass)
• Tributaries: Chandra River, Bhaga River, Ravi River
• Key Projects: Salal Dam (1,830 MW), Baglihar Dam (900 MW), Dhulhasti Dam (390 MW), Ratle Project (850 MW - disputed).

Also read: List of Major Dams of India for UPSC: Oldest, Longest & Highest Dams in India

The Indus Waters Treaty is often praised, but India and Pakistan have still faced many issues while using it. These ongoing problems help explain why the treaty is under pressure now.

1. Baglihar Dam Dispute (2005): 

• Pakistan objected to the design of India's Baglihar Dam on the Chenab River, claiming it violated treaty provisions.
• The Neutral Expert ruled in India's favour, stating the dam's design was compliant with treaty restrictions.​

2. Kishanganga Project Dispute (2013-2018): 

• Pakistan objected to India's 330 MW Kishanganga Hydroelectric Project on the Kishanganga River (Neelum), claiming it would reduce water flow downstream.
• The Court of Arbitration ruled that India must maintain a minimum flow of 9 cubic meters per second (cumecs) to Pakistan.​

3. Ratle Project Dispute (2013-2024): 

• Pakistan alleged that India's 850 MW Ratle Hydroelectric Project on the Chenab River violated the IWT.
• The World Bank approved the project, but disputes continue regarding design specifications.​

4. Information Sharing Disputes: 

• Pakistan has repeatedly raised concerns that India doesn't provide adequate prior information about dam construction, water releases, and project designs.​

5. Fundamental Disagreement on Treaty Modernisation (2023): 

• India requests modifications to the treaty, claiming it is outdated and doesn't reflect current security realities.
• Pakistan categorically refuses, stating that renegotiating the treaty could threaten its food security.

Also read: Ganga River System: Origin, Course, Tributaries, Maps | Complete UPSC Notes

Suspending the Indus Waters Treaty is a serious threat to Pakistan because its farming, food supply, and overall survival depend heavily on the Indus River.

• Reduced water could lead to diminished agricultural output, causing food shortages and price inflation that would hurt Pakistan's economy and population.
• Unlike India, which is building reservoirs and dams, Pakistan lacks the infrastructure to store water from high-flow seasons for use during low-flow periods.
• Reduced water flow affects hydroelectric power generation, which provides significant electricity to Pakistan. Lower water means less power generation and increased reliance on expensive fossil fuels.
• Food insecurity from crop failures would lead to widespread malnutrition, especially among children.
• Industries dependent on water (textiles, manufacturing) could face severe disruptions, affecting employment and exports.

India has built many dams and canals on the Indus system to use its water shares. These can be grouped by river basins:

1. Eastern Rivers (Sutlej, Beas, Ravi): India has completed large multipurpose projects on all three rivers.

• Bhakra Dam (Satluj): India’s tallest gravity dam, forming the Gobind Sagar reservoir, with huge irrigation and power capacity.
• Pong Dam (Beas): Creates Maharana Pratap Sagar reservoir for hydroelectricity.
• Pandoh Dam (Beas): Diverts Beas water into the Satluj (via the Beas–Satluj link canal) for power generation at Dehar.
• Thein (Ranjit Sagar) Dam (Ravi): A large reservoir on the Ravi feeding canals in Punjab.
• Beas–Sutlej Link: Canal bringing Beas water into the Satluj basin (enabled Bhakra’s full use).
• Indira Gandhi Nahar Project (IGNP): A canal (Rajasthan Canal) linking the Sutlej water to irrigate western Rajasthan.
• Shahpurkandi Dam (Ravi): This ongoing project will store flows below Thein Dam. Construction was resumed in 2018 after agreements between the states (J&K and Punjab).
• Ujh Multipurpose Project (Ravi tributary): It is declared a National Project to utilise eastern surplus flows.

2. Western Rivers (Jhelum and Chenab basins in J&K/Himachal): India has also developed projects on western rivers (allowed as run-of-river projects):

• Kishenganga Hydroelectric Plant (Jhelum): 330 MW project in J&K, diverting waters through a tunnel to the Wular Lake.
• Uri I and II (Jhelum): Hydropower plants (240 MW and 240 MW) in Kashmir along the Jhelum.
• Dulhasti Hydropower Project (Chenab): 390 MW power plant in J&K on the Chenab.
• Salal Dam (Chenab): 690 MW pumped-storage project in J&K (operational).
• Chenab Projects – Pakal Dul (1000 MW) and Ratle (850 MW): Under construction in J&K on the Chenab. Ratle’s design is contested by Pakistan and is part of the current dispute.
• Baglihar Dam (Chenab): 900 MW plant in J&K, whose design had earlier been reviewed by a Neutral Expert (2007).
• Chamera Dams (Chenab tributary Ravi in HP): Multiple projects (630 MW, 300 MW, 231 MW) on the Chamba–Fatehpur canal (a Chenab tributary).

Also read: All you need to know about the Shimla agreement

The Indus Waters Treaty is now suspended by India after 65 years in April 2025, following the Pahalgam terror attack.

• Following a terror strike in Pahalgam, Jammu & Kashmir, on April 22, 2025, India suspended the treaty indefinitely, marking the first time in six decades.
• Pakistan continued with the neutral expert hearings in Vienna (17–21 November 2025) even without India.
• India stated it will not recognise any decisions from the Vienna-based Permanent Court of Arbitration, calling the proceedings “null and void” as the treaty remains suspended.

The suspension of the IWT marks a turning point in India's water strategy. Going ahead, India is likely to pursue a future-focused, power-building approach where water is treated not just as a shared resource but as a strategic national asset.

Prime Minister Narendra Modi recently emphasised this shift, stating: “India’s water will now serve India’s interests.” He also highlighted that past policies allowed water to flow, but now, India is committed to conserving its rivers for development.

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