SYLLABUS

GS-2: Functions and Responsibilities of the Union and the States, Issues and Challenges Pertaining to the Federal Structure. 

Context: The Centre has reiterated in Parliament that the Supreme Court's 2018 Cauvery judgment does not expressly mandate Karnataka to obtain the consent of lower riparian States before undertaking a new construction across the Cauvery River. The clarification has revived the debate over Karnataka's proposed Mekedatu Balancing Reservoir-cum-Drinking Water Project.  

Evolution of the Cauvery Dispute

• Inter-State River: The Cauvery River is shared by Karnataka, Tamil Nadu, Kerala and Puducherry, making it one of India's most contested inter-State rivers due to competing demands for irrigation, drinking water and ecological needs. 

• Cauvery Water Disputes Tribunal (CWDT): Constituted in 1990 under the Inter-State River Water Disputes Act, 1956, the Tribunal delivered its final award in 2007, allocating the 740 TMC of utilisable water as follows: 

• Tamil Nadu: 419 TMC 
• Karnataka: 270 TMC 
• Kerala: 30 TMC 
• Puducherry: 7 TMC 
• The remaining 14 TMC was earmarked for environmental protection and inevitable escapages into the sea. 

• Supreme Court Judgment (2018): Recognising Bengaluru's growing drinking water requirements, the Supreme Court increased Karnataka's allocation by 14.75 TMC to 284.75 TMC and correspondingly reduced Tamil Nadu's allocation to 404.25 TMC. 

• It also recognised Tamil Nadu's entitlement to draw 10 TMC of groundwater, while leaving the allocations of Kerala (30 TMC) and Puducherry (7 TMC) unchanged. 

• Institutional Mechanism: The Court also directed the establishment of the Cauvery Water Management Authority (CWMA) and the Cauvery Water Regulation Committee (CWRC) to implement the water-sharing framework and regulate reservoir operations among the basin States. 

What is the Mekedatu Project?

• Location: The proposed Mekedatu Balancing Reservoir-cum-Drinking Water Project is planned across the Cauvery River at Mekedatu in Ramanagara district, Karnataka, downstream of the confluence of the Cauvery and Arkavathi rivers. 

• Site Selection: Mekedatu (meaning "goat's leap" in Kannada) is a narrow gorge where the Cauvery flows through steep rocky terrain, making it a suitable location for constructing a balancing reservoir. 

• Objectives: Karnataka proposes the project to: 

• Supply drinking water to Bengaluru and nearby areas; 
• Generate hydroelectric power; and 
• Store and regulate water within its allocated share under the Cauvery water-sharing arrangement. 

• Present Status: Although Karnataka has prepared the Detailed Project Report (DPR), the project has not received the necessary statutory and environmental approvals and continues to face objections from Tamil Nadu. 

Why is the Mekedatu Project Controversial?

• Karnataka's Position

• The project seeks to utilise Karnataka's allocated share of Cauvery waters without altering the Tribunal's allocation. 
• It aims to store surplus monsoon flows within Karnataka's allocated share for drinking water supply, hydropower generation and regulated releases. 
• Karnataka argues that the project is essential to meet the growing drinking water requirements of Bengaluru and surrounding regions. 

• Tamil Nadu's Concerns

• Tamil Nadu argues that an upstream storage reservoir could enable Karnataka to regulate water releases, particularly during distress years, affecting the timely availability of water for irrigation and drinking purposes downstream. 
• It fears that the project could undermine the effective implementation of the CWDT Award and the Supreme Court's 2018 judgment. 
• Tamil Nadu maintains that the project should not proceed without all statutory clearances and without adequately safeguarding the interests of downstream riparian States.

Way Ahead

• Strengthen Statutory Institutions: Empower the CWMA and CWRC with transparent reservoir monitoring, real-time data sharing and effective enforcement of the Cauvery water-sharing framework. 

• Institutionalise Political Dialogue: While statutory bodies should implement the award, forums such as the Inter-State Council and Southern Zonal Council can facilitate political dialogue and consensus-building on long-term inter-State river issues. 

• Adopt Scientific River Basin Management: Base decisions on comprehensive hydrological, environmental and ecological assessments to balance urban water security with downstream irrigation and ecological flow requirements. 

• Promote Sustainable Water Management: Complement infrastructure projects with measures such as rainwater harvesting, wastewater recycling, micro-irrigation and demand-side water management to reduce pressure on the Cauvery basin.