SYLLABUS
GS-2: Functions and responsibilities of the Union and the States, issues and challenges pertaining to the federal structure; Powers, functions and responsibilities of various Constitutional Bodies.
Context: Recently, the Supreme Court directed the Union Government to constitute a Tribunal within a month for resolving disputes between the States of Tamil Nadu and Karnataka over the sharing of Pennaiyar river water.
Background of the Dispute
• Tamil Nadu filed an original suit in 2018 under Article 131 of the Constitution, invoking the Supreme Court’s original jurisdiction in disputes between States and the Union.
• The dispute relates to dams and diversion structures constructed by Karnataka on the Pennaiyar and its tributary Markandeya River.
• Tamil Nadu argued that while the flow of water of an inter-State river is a national asset and no single state can claim exclusive ownership of its water, Karnataka’s projects adversely affect downstream water availability and violate existing agreements.
- Karnataka is the upper riparian State while Tamil Nadu is the lower riparian State in the Pennaiyar river basin.
Negotiations and Mediation Efforts
- The Union Government initially explored the possibility of resolving the dispute through negotiations between the States.
- In January 2024, the Supreme Court directed the constitution of a negotiation committee under the Inter-State River Water Disputes Act 1956.
- The Court noted that the Act allows tribunal formation only after failure of negotiations within one year.
- In November 2024, the Court was informed that mediation between the States had failed, necessitating recourse to the tribunal mechanism.
About the River Water Disputes Tribunals
- The Inter-State River Water Disputes (ISWD) Act, 1956, is the primary legislation enacted by Parliament under Article 262 of the Constitution to resolve disputes between states over waters of inter-state rivers or river valleys.
- Under the Act, the Union Government has constituted multiple ad-hoc inter-State river water dispute tribunals over the years to adjudicate specific disputes between States.
- The awards of inter-State river water dispute tribunals are final and binding on the parties.
- Under Article 262(2) of the Constitution and Section 11 of the ISWD Act, 1956, the jurisdiction of the Supreme Court and High Courts is expressly barred in respect of water disputes referred to a tribunal.
- While the proposal for a permanent tribunal was a central feature of the Inter-State River Water Disputes (Amendment) Bill, 2019, the bill officially lapsed upon the dissolution of the 17th Lok Sabha in 2024.
- Current Framework: As the amendment did not become law, the Inter-State River Water Disputes Act, 1956, remains in effect. This means the government must still set up ad-hoc (temporary) tribunals for each specific dispute rather than using one permanent body.

About Pennaiyar River
- The Pennaiyar River, also known as the South Pennar, Ponnaiyar or Dakshina Pinakini, is a 576 km east-flowing Peninsular river, flowing through Karnataka and Tamil Nadu.
- It is the second-largest interstate east-flowing river basin located between the Pennar and Cauvery basins.
- Major tributaries include Markandeya, Pambai, and Chinnar.
- Origin: It rises at an elevation of about 900 metres in the Nandi Hills of the Chikkaballapura district in Karnataka.
- Path: From its source, it flows southward for about 80 km in Karnataka before entering Tamil Nadu near Hosur. It then travels southeast for another 320–420 km, eventually emptying into the Bay of Bengal near Cuddalore.
- Basin Distribution: The total drainage area is approximately 16,019 sq. km. Tamil Nadu holds about 77% of this basin, with the remainder in Karnataka (~22%) and a tiny portion in Andhra Pradesh.
