THE HAGUE: The Permanent Court of Arbitration (PCA) in The Hague hearing Pakistan’s case against India under the Indus Waters Treaty of 1960 has issued a landmark award stating that “India must let flow Western River waters for Pakistan’s unrestricted use.”
It also clarified how the agreement between the two countries applies to Indian hydro-electric projects on the Indus, Jhelum and Chenab rivers, known as the Western Rivers.
The tribunal, constituted in 2022 after Pakistan invoked the treaty’s dispute resolution provisions, ruled on August 8 that run-of-river plants India may build on these rivers must strictly comply with treaty requirements, even if engineering “best practices” suggest otherwise.
In June this year, the Court of Arbitration declared that India’s decision to suspend the Indus Waters Treaty was illegal.
The breakthrough came days after India said it will never restore the Indus Waters Treaty with Islamabad, and the water flowing to Pakistan will be diverted for internal use.
“India has refused to participate in the proceedings and challenged the court’s competence, but the panel unanimously ruled in July 2023 – and reaffirmed in June 2025 – that it had jurisdiction. India’s April 2025 declaration that it would hold the treaty “in abeyance” did not affect the court’s authority,” the PCA said in a press release.
The arbitration court stressed it had kept India informed and considered its positions from past proceedings and public records, while rigorously testing Pakistan’s claims.
“The award sets out binding interpretations of key treaty provisions. It confirms that decisions by a court of arbitration are final and control subsequent dispute bodies, while neutral expert determinations are binding only within their mandate and on the specific project addressed.”
Citing Pakistan’s downstream vulnerability and the potential for conflict, the court said the “treaty’s purpose is to clearly delimit the parties’ rights and obligations, backed by cooperation and effective dispute resolution.”
Under Article III and Annexure D, India must “let flow” Western River waters for Pakistan’s unrestricted use, with limited, narrowly construed exceptions for hydro-power. Design elements addressed in detail include:
Low-level outlets
“India should avoid them unless no other effective method exists for sediment control or other technical needs. If unavoidable, outlets must be minimal in size and as high as possible in the dam,” the ruling said.
Gated spillways
It said that crest gates should be avoided unless necessary for floods or sediment management, and if used, must be positioned at the highest feasible level.
The court emphasised early cooperation, requiring India to adjust designs in response to Pakistan’s valid objections, and placing the burden on India to prove treaty compliance.
The ruling did not yet apply these findings to the Kishenganga and Ratle hydro projects cited in Pakistan’s arbitration request. Those issues remain before the court, which will consult the parties on next steps.
The five-member panel waschaired by US professor Sean D Murphy, with members from Belgium, the US, Jordan and Australia.