Pakistan expressed on Sunday “utmost satisfaction” over a supplemental award by the Permanent Court of Arbitration (PCA) that it said affirmed Islamabad’s position of the Indus Waters Treaty placing “substantive limits on India’s water-control capability” on Indus River system’s western rivers.
The decision pertained to maximum pondage – a technical term for the maximum volume of water that could be stored in a reservoir – in Indus Waters Treaty proceedings arising from design disputes concerning the Ratle Hydroelectric Plant and the Kishenganga Hydroelectric Project in occupied Kashmir, a statement issued by the Pakistan government said.
According to the statement, the supplemental award was issued on May 15. However, the decision has not been publicly shared by the PCA yet.
Pakistan had first instituted arbitral proceedings against India regarding the Indus Waters Treaty (IWT) in 2016. And while India continues to boycott the proceedings, the court shares its procedural updates and decisions with both Indian and Pakistani Indus water commissioners ex-officio.
According to the government of Pakistan’s statement, the latest supplemental award by the PCA affirmed Islamabad’s “central position that the treaty places substantive limits on India’s water-control capability on the western rivers”.
“These limits are not formalities. They apply at the planning and design stage and cannot be satisfied merely by a later assurance of operational restraint.
“Pondage for a run-of-river Plant must be justified by real project needs, actual expected operation, site hydrology, hydraulic conditions, power-system requirements, and the information and explanation required under the treaty,” the statement said.
It added that building on the PCA’s Award on Issues of General Interpretation of the IWT on August 8, 2025, the supplemental award gave practical effect to the standard that installed capacity and anticipated load must be realistic, well-founded and defensible.
“Installed capacity must correspond to actual expected operation, hydrologic and hydraulic data, and treaty requirements. Anticipated load must correspond to actual expected operation and to the projected needs of the power system the plant is intended to serve,” it said.
This, the statement said, addressed a core IWT concern that “India cannot justify increased pondage through imagined capacity, artificial load curves, unrealistic peaking assumptions, or bare assertions of compliance with paragraph 15 release limits”.
The statement said the award also strengthened Pakistan’s review rights.
“India must provide Pakistan with sufficient information and explanation to assess treaty compliance. If India fails to do so, it fails to carry its burden of establishing that the proposed maximum pondage satisfies Paragraph 8(c) of Annexure D,” it stated.
The said provision elaborates on the design of any new run-of-river plant, stating that the “maximum pondage in the operating pool shall not exceed twice the pondage required for firm power”.
According to the Pakistan government’s statement, the PCA also confirmed that “any applicable minimum-flow obligation must be taken into account in calculating pondage required for firm power where such obligation exists and is not otherwise satisfied. Paragraph 15 release requirements do not automatically satisfy such an obligation”.
It said Pakistan “also notes the Court’s earlier holding that the awards of a court of arbitration are final and binding on the parties and have otherwise controlling legal effect for subsequent treaty bodies on relevant questions of treaty interpretation”.
“Pakistan will place these interpretations before the neutral expert process, consistent with treaty procedures and applicable confidentiality arrangements,” it added.
The statement further said that Pakistan remained committed to the Indus Waters Treaty, its dispute-resolution procedures, and the peaceful settlement of water-related differences.
“Pakistan will continue to protect its rights under the IWT and will pursue every lawful and diplomatic means to ensure that hydroelectric projects on the western rivers are designed and operated strictly within treaty limits.
“The award is a strategic consolidation of Pakistan’s treaty position: maximum pondage must be realistic, evidence-based, hydrologically grounded, power-system justified, treaty-compliant, and incapable of inflation through artificial assumptions,” the statement read.