India has suspended the Indus Waters Treaty with Pakistan on Wednesday, April 23 2025, a day after 28 people were killed in a terrorist attack in Jammu and Kashmir’s Pahalgam.

The move is among the five big punitive moves taken by New Delhi against Islamabad in the wake of the terror attacks.

What is Indus Water Treaty?

The Indus system comprises the main river, Indus, and five left bank tributaries, i.e Ravi, Beas, Sutlej, Jhelum, and Chenab.

The Indus Waters Treaty is a water-sharing agreement signed in 1960 between India and Pakistan, with help from the World Bank. The main aim was to settle how both countries would use the rivers that flow from the Himalayas into their territories. After the partition in 1947, both countries relied heavily on these rivers for farming and drinking water, which made the issue quite sensitive.

Under the treaty, six rivers were divided between the two nations. India got full control over the three eastern rivers—Ravi, Beas, and Sutlej. Pakistan, on the other hand, received the rights to use the three western rivers—Indus, Jhelum, and Chenab. India can still use the western rivers for certain purposes, like generating hydroelectric power, but it can’t reduce the flow of water to Pakistan.

To keep things running smoothly, a Permanent Indus Commission was set up. This commission has officials from both countries who meet regularly to share data and sort out any disagreements.

What could be the impact of this move?

Pradeep Kumar Saxena, who served as India’s Indus Water Commissioner for over six years, told PTI,” India, as an upper riparian country, has multiple options. This could be the first step towards the abrogation of the Treaty, if the Government so decides.”

“Although there is no explicit provision in the Treaty for its abrogation, Article 62 of the Vienna Convention on Law of the Treaties provides sufficient room under which the treaty can be repudiated in view of the fundamental change of circumstances which has occurred with regard to those existing at the time of conclusion of the Treaty,” he added.

Last year, India in a formal notice to Pakistan, sought the “review and modification” of the treaty.

According to Saxena, India is under “no obligation” to follow the restrictions on the “reservoir flushing” of the Kishanganga reservoir and other projects on Western rivers in Jammu and Kashmir.

“The Indus Water Treaty currently prohibits it. Flushing can help India desilt its reservoir but then filling the entire reservoir could take days. Under the treaty, reservoir filling after the flushing has to be done in August — peak monsoon period — but with the pact in abeyance, it could be done anytime,” he told PTI.

However, carrying out the exercise when sowing season begins in Pakistan could be “detrimental”, especially when a large part of Punjab in Pakistan depends on the Indus and its tributaries for irrigation.

According to the treaty, design restrictions exist on building structures like dams on the Indus and its tributaries. Earlier, Pakistan has raised objections over the designs, but in the future, it will not be obligatory to take the concerns on board .

In the past, almost every project has been objected to by Pakistan, the notable ones are Salal, Baglihar, Uri, Chutak, Nimoo Bazgo, Kishenganga, Pakal Dul, Miyar, Lower Kalnai and Ratle.

After the Pulwama terror attack in 2019, the government cleared eight more hydropower projects in Ladakh. The objections may no longer apply to the new projects. There are also operational restrictions on how reservoirs are to be filled and operated.

With the treaty in abeyance, these are no longer applicable. Saxena told PTI that India can stop sharing flood data on the rivers.

“This could also prove detrimental to Pakistan, especially during the monsoon when rivers swell. India will now have no restriction on storage on Western rivers, particularly the Jhelum, and India can take several flood control measures to mitigate floods in the Valley,” Saxena added.

Looking forward

Despite India’s suspension of the Indus Waters Treaty, water will not stop flowing into Pakistan overnight. The main reason is practical: India currently lacks the infrastructure to block or divert the natural flow of the Indus, Jhelum, and Chenab rivers, which supply most of Pakistan’s water.

Building the large dams and reservoirs needed to hold back or redirect these rivers would take years, if not longer, and require major investment and planning. For now, the rivers will continue to flow into Pakistan as they always have, though India may stop sharing water flow data or halt the regulated releases from its hydro projects

What changes immediately is the sense of predictability and security that the treaty provided for over sixty years. Pakistan’s farmers, cities, and power stations have relied on a steady, reliable flow of water from these rivers. With the treaty suspended, India is no longer bound by earlier restrictions on dam construction or water usage, and could, over time, increase its own use or alter the timing of water releases. This could eventually reduce the water available to Pakistan, especially during critical farming seasons or dry months.

But for now, any impact will be gradual, not sudden. The real risk is that uncertainty will grow, making it harder for Pakistan to plan for the future and increasing tensions between the two countries.