News: Tamil Nadu urged the Union Government to reject statutory approvals for Karnataka's Mekedatu Balancing Reservoir Project.

About Cauvery River

• One of India's major east-flowing peninsular rivers, also known as the "Dakshin Ganga" (Ganga of the South) or Ponni.
• Origin: Talakaveri, Brahmagiri Hills, Western Ghats, Kodagu (Karnataka).
• Length: ~800 km.
• Mouth: Empties into the Bay of Bengal at Poompuhar (Tamil Nadu).
• Basin Area: ~87,900 sq km across Karnataka, Tamil Nadu, Kerala, and Puducherry.

Major Tributaries

• Left Bank: Harangi, Hemavati, Shimsha, Arkavati.
• Right Bank: Lakshmantirtha, Kabini, Suvarnavati, Bhavani, Noyil, Amaravati.
• Cauvery Water Sharing
• CWDT Award (2007): Allocated river water among Karnataka, Tamil Nadu, Kerala, and Puducherry.

Supreme Court Judgment (2018):

• Increased Karnataka's share to 284.75 TMC.
• Reduced Tamil Nadu's share to 404.25 TMC.
• Karnataka must release 177.25 TMC annually to Tamil Nadu at Biligundlu.

Mekedatu Project

• Proposed multipurpose balancing reservoir by Karnataka.
• Location: Ramanagara district, at the confluence of Arkavati and Cauvery, near the Tamil Nadu border.

Objectives:

• Supply 4.75 TMC drinking water to Bengaluru.
• Generate 400 MW hydropower.

Concern: Submergence of 3,000–4,900 hectares of forest within the Cauvery Wildlife Sanctuary, leading to environmental and interstate water-sharing concerns.