Indus Waters Treaty Explained: Why India Seeks Renegotiation of the 1960 Pact Held in Abeyance

Origin of the treaty: The Partition of 1947 split one of the world's most integrated irrigation systems between India (upper riparian) and Pakistan (lower riparian), creating disputes over canal waters. After nearly a decade of negotiations brokered by the World Bank, the Indus Waters Treaty was signed on 19 September 1960 at Karachi by Prime Minister Jawaharlal Nehru and President Ayub Khan, with the World Bank as a signatory to certain provisions.

The partition of rivers: The treaty allocates the three eastern rivers — Ravi, Beas, and Sutlej (average annual flow about 33 million acre-feet, MAF) — to India for unrestricted use, and the three western rivers — Indus, Jhelum, and Chenab (about 135 MAF, roughly 80% of the basin's waters) — to Pakistan. India must let the western rivers flow unrestricted, but may use them for specified non-consumptive purposes: run-of-the-river hydropower, limited irrigation, navigation, and limited storage (about 3.6 MAF). Pakistan may use whatever eastern-river water flows into its territory.

Institutional machinery: The treaty created the Permanent Indus Commission (PIC), with a Commissioner from each country, required to meet at least once a year, to implement the treaty and resolve questions. Disputes escalate through a three-tier mechanism: questions before the PIC, differences before a World Bank-appointed Neutral Expert, and disputes before a Court of Arbitration.

Abeyance since April 2025: Following the Pahalgam terror attack, India's Cabinet Committee on Security decided to hold the treaty in abeyance until Pakistan credibly and irreversibly abjures support for cross-border terrorism. Since then, PIC meetings and treaty data-sharing have remained suspended. India has framed the abeyance as an exceptional response to an extraordinary security situation, arguing that a treaty concluded in good faith cannot bind one party while the other sponsors violence against it.

India's renegotiation notices: Separately — and preceding the abeyance — India issued notices to Pakistan in January 2023 and September 2024 under Article XII(3), seeking modification and renegotiation of the treaty in view of fundamental changes over six decades: demographic shifts, clean-energy requirements, engineering advances, and climate-driven variability. Pakistan has not responded substantively to either notice.

Legal proceedings: Pakistan has pursued arbitration; the Court of Arbitration held in June 2025 that the treaty does not provide for unilateral abeyance and, in May 2026, ruled on maximum pondage limits for Indian run-of-river projects. India rejected these awards as null and void, holding the Court's very constitution illegal, since the treaty bars parallel proceedings and a Neutral Expert was already seized of the same questions. The Neutral Expert's final award of April 2026 on the Kishenganga and Ratle design questions is widely read as vindicating India's technical positions.

Rivers are dynamic, the treaty is static: In his Indian Express analysis, Amitabh Sinha argues that as river flow and water use change, and as dependent populations, technologies, and scientific knowledge evolve, the management of rivers cannot remain a static arrangement — yet the IWT has never been amended, and its provisions were framed for the realities of the 1950s.

Missing modern elements: The treaty makes no mention of groundwater, even though aquifers, like surface waters, are connected across boundaries. It has no provisions on water quality or on maintaining environmental flows. Pakistan, for example, has repeatedly complained that municipal and sewage waste in the eastern rivers — which flow unrestricted into Pakistan when full, under the treaty — adversely affects soil and water health downstream. Such issues simply lie outside the treaty's framework.

Climate change: No treaty negotiated before the 1990s could have factored in climate change. A recent study by IIT Gandhinagar researchers Vimal Mishra and Urmin Vegad shows climate change is affecting water availability differently across the Indus basin: the eastern river basins have seen a decline of about 20% in annual rainfall over the last 70 years, while precipitation in the western basins has remained largely unchanged. A fixed partition of rivers cannot respond to such asymmetric hydrological change.

Clean partitioning versus volumetric sharing: Most water-sharing agreements worldwide ensure each party the availability of a certain volume of water, or a minimum percentage of flows, from the shared rivers. The IWT is a rare example of an agreement in which entire rivers are allocated to one party or the other. This is why it is often described as a partition agreement rather than a water-sharing arrangement.

Consequence for cooperation: Analysts argue this clean partitioning is one of the main reasons for the lack of interest in developing joint river basin management programmes in the Indus basin — each side manages "its" rivers, with little incentive for basin-wide cooperation on floods, sediment, ecology, or data.

Treaties evolve constantly: A 2013 study identified at least 250 separate transboundary river-water-sharing treaties covering 113 river systems; counting supplementary protocols, amendments, and navigational or data-sharing arrangements, the total came to 688 instruments — a number that now exceeds 800 according to the International Freshwater Treaties database maintained by Oregon State University. The growth from 250 base treaties to 800-plus instruments for roughly the same 100-plus river systems shows that such agreements are routinely reviewed and updated to reflect new ground realities.

The Mekong model: The 1995 Mekong Agreement in Southeast Asia illustrates a more flexible design. While the PIC functions essentially as an implementing agency focused on ensuring the IWT's provisions are not violated, the Mekong River Commission acts as a joint river-water management system: it cannot change the treaty itself, but it is empowered to develop and revise joint basin management strategies, data-sharing protocols, and water quality rules.

India's own practice: India's 1996 Ganga Waters Treaty with Bangladesh was concluded with a 30-year validity and is due for renewal in 2026 — a built-in periodic review of the kind the IWT lacks. Many transboundary arrangements worldwide similarly contain provisions for periodic review.

Article VII — future cooperation: The treaty itself recognises evolution: Article VII allows the two countries to undertake new drainage or other river engineering works through mutual agreement and cooperation. This provision has never been used.

Article XII — modification: Article XII permits modification of the treaty's provisions "from time to time", but only through another duly ratified treaty concluded between the two governments — and until then, the treaty continues in force. It is this provision India invoked to serve its 2023 and 2024 notices seeking modification or complete renegotiation. Because amendment requires mutual consent, one party's refusal to engage can freeze the treaty in its 1960 form — the central difficulty now on display.

India's position: India maintains that the abeyance responds to Pakistan's undermining of the treaty's good-faith foundations through cross-border terrorism, and that renegotiation is separately justified by fundamental changes — population growth, clean energy needs, engineering advances, and climate change. Commentators, including Sinha, note that India's request to renegotiate should be seen as delinked from the abeyance decision; indeed, agreeing to renegotiate may be the most reliable way for Pakistan to ensure the treaty is no longer held in abeyance.

Pakistan's position: Pakistan holds that the treaty remains valid, operational, and binding, that it contains no provision for unilateral suspension — a view the Court of Arbitration endorsed — and has characterised the abeyance as a weaponisation of water, citing its lower-riparian dependence: the Indus system irrigates the bulk of its agriculture, which draws heavily on glacier-fed western river flows. It has sought resumption of normal treaty functioning through letters and international forums.

The basin's stakes: The Indus basin spans about 11.2 lakh sq km across four countries — Pakistan (47% of basin area), India (39%), China (8%), and Afghanistan (6%) — making the treaty's future consequential for regional water security well beyond the two signatories.

The Indus basin needs an arrangement that keeps water cooperation insulated from conflict while being scientifically current. The most durable path is the one the treaty itself provides: negotiations under Article XII(3) to update the pact for groundwater, water quality, environmental flows, climate variability, and modern engineering standards, alongside credible and verifiable action by Pakistan on cross-border terrorism to address the trust deficit that produced the abeyance. A modernised framework could move from the rigid partition of entire rivers towards elements of joint basin management — shared hydrological and glacier-melt data, flood forecasting, sediment and ecology protocols — drawing on the Mekong River Commission model, with the PIC's mandate expanded from compliance-policing to cooperative basin planning. Periodic review clauses, of the kind embedded in the Ganga Treaty and most modern water agreements, should be built in so that the arrangement evolves with the river. For India, pursuing renegotiation from its current position of technical and legal strength, while continuing to develop its full entitlements on the eastern and western rivers within a sound framework, best serves both water security and regional stability.