rivers Indus and Zanskar at Nimoo valley

The confluence of rivers Indus and Zanskar at Nimoo valley in Leh, India. Credit: Subhra Priyadarshini© S.Priyadarshini

A parliamentary committee in India has urged the government to renegotiate a 61-year-old pact with Pakistan to factor in the impact of climate change and pollution on the Indus river, which the two countries share.

The committee’s report released in August 2021 said renegotiation was essential to establish a framework that addresses “pressing issues such as climate change, global warming and environmental impact assessment” on water availability in the Indus basin. It is India’s first attempt to re-assess the Indus Water Treaty (IWT) from a scientific standpoint.

The IWT is a pact for cooperation and information exchange on river management. Signed in 1960 with the help of the World Bank after nine years of negotiations between India and Pakistan, the treaty is held up as a success, especially given its longevity despite the strain of longstanding troubled relations between the neighbouring countries.

Pakistan was allocated waters of the Indus and its westward flowing tributaries, the Jhelum and Chenab, while India had exclusive rights over the eastern rivers — Ravi, Beas and Sutlej. The modalities were confined to water usage through construction of dams, barrages, canals and hydro-power generation.

“There is very little in the treaty for the best possible use of the water resources of the river system,” said Ashok Swain, director of Research School for Water Cooperation, Uppsala University, Sweden, agreeing that a review to account for environmental challenges was in order.

“IWT negotiations were an exercise in diplomacy. But now with climate change and environmental pollution, it is critical the treaty is renegotiated,” Maharaj Pandit, an environmental studies professor at University of Delhi, told Nature India.

Science was not represented well in the treaty negotiated by engineers in 1960, according to Daanish Mustafa, a professor of critical geography at King’s College London. The two countries need to think about base flows of the rivers rather than taking an averages-based approach to measure water flow, Mustafa said.

New water demands on the basin, Swain said, necessitated a renegotiation since the 1960 treaty was “not a water sharing treaty, but primarily a partition of the river system — three rivers given to Pakistan and three to India.” The entire Indus basin should be seen as a single unit for the best possible use, he said.

The treaty includes a mechanism to refer ‘disputes’ to a seven-member arbitration tribunal. The neighbours have taken disputes over hydropower projects to this court, and have accepted the ensuing verdicts.

An over-stressed aquifer

In June 2015 NASA ranked the Indus basin as the world’s second most over-stressed aquifer. It said depleting groundwater in the Indus basin could worsen the water crisis in the subcontinent.

Indus water is fed by glaciers that are receding. “It makes the Indus basin vulnerable to vagaries of climate change. Water availability in Indus will be compromised,” Pandit said.

A 2019 assessment report by Kathmandu-based International Centre for Integrated Mountain Development pointed to the melting of one-third of the glaciers which feed the Indus basin. Another study reported that nine benchmark glaciers in Kashmir Himalayas have shrunk by 17%1 between 1980 and 2013.

Pandit said per capita consumption of water has increased with growing population of the region, leading to reduction of per capita availability of water. Other basins such as Ganges and Brahmaputra are less vulnerable as their waters are not entirely dependent on glacial melt. “Rain contributes a large volume of water to those rivers whereas the Indus is mostly dependent on solid precipitation or ice-field,” he said.

Moving beyond politics

Given the risks, Pakistan is more vulnerable as almost 70% of the country’s GDP depends on the Indus, Pandit said. “All its exports, whether Basmati rice or textiles, depend upon the Indus basin. Islamabad must pay heed to the call to address climate change and environmental issues, he said.

A review of the treaty can happen when both India and Pakistan see the benefits of looking at the climate impacts, Swain said.

Scientific knowledge should be the guiding factor rather than political considerations, said Shakil Romshoo, lead author of several studies on glaciers in the Himalayan region, and vice chancellor of Islamic University of Science and Technology in Kashmir.

“On the basis of current scientific knowledge, revising the treaty should be considered to incorporate the many new issues that have significantly impacted water availability and distribution,” Romshoo told Nature India.