Context: Recently, Chief Minister of Tamil Nadu laid the foundation stone for the first phase of the Cauvery-South Vellar-Vaigai-Gundar intra-State river-link project.

Background

• The first significant step towards the linking of the Cauvery and Gundar rivers was made with the commissioning of the barrage across Cauvery at Mayanur in Karur district in 2014.

Key Points

• Tamil Nadu is all set to launch its ambitious intra-State river linking project by building a canal from the Cauvery to the Vaigai and the Gundar. 
• The massive project seeks to divert surplus flows from the Cauvery to the water scarce southern parts of the State.
• In the first phase, the canal will run through Karur (47.23 km), Tiruchi (18.89 km) and Pudukottai district (52.32 km). 
• The second phase will involve linking the South Vellar and Vaigai rivers, a distance of about 110 km, and the third final phase will link the Vaigai with the Gundar (34.04 km).
• The project forms part of the peninsular rivers’ development component of the National Perspective Plan envisaging diversion of surplus flows of the Mahanadi basin and the Godavari basin to the water-short Krishna, Pennar, Cauvery, Vaigai and Gundar basins in the South.
• The barrage will form the head of the new link canal which will run a distance of 262.19 km to carry the surplus waters from the Cauvery to the South Vellar, the Vaigai river and finally the Gundar. The canal will have a capacity to carry about 6,000 cusecs of water.

Kaveri–Vaigai Link Canal

• Kaveri–Vaigai Link Canal Project is a project envisioned by the Government of Tamil Nadu, linking Kaveri and Vaigai rivers.
• Tamil Nadu is one of the states in southern India which depends heavily on the rivers flowing from the neighboring states of Kerala and Karnataka.
• Hence, the state government started this project linking Kaveri and Vaigai rivers which would benefit during the drier seasons.
• The project involves construction of a 60-kilometre (158.82 mi) long canal from Mayanur in Karur district to link river Kaveri with Vaigai.
• According to the National Water Development agency, the gravity canal will provide water for irrigating an additional area of 3.38 lakh hectares and for domestic and industrial water supply.

Additional Information

• Source: The river rises on Brahmagiri Hill of the Western Ghats in southwestern Karnataka.
• Drainage Basin: It flows in a southeasterly direction through the states of Karnataka and Tamil Nadu, and descends the Eastern Ghats in a series of great falls. Before emptying into the Bay of Bengal south of Cuddalore, Tamil Nadu, the river breaks into a large number of distributaries forming a wide delta called the “garden of southern India.”
• Tributaries: Arkavathi, Hemavathi, Lakshmana Theertha, Shimsa, Kabini and Harangi.

• Source of origin of the Vaigai river: It rises from the hills of Varushanad in Madurai district in the state of Tamil Nadu.
• Confluence or mouth of the Vaigai river: The Vaigai drains into the Palk Bay near Mandapam.
• Major Tributaries of the Vaigai river: The Siruliar River; The Theniar River; The Varaha Nadi; The Mangalar River; The Vaigai river basin
• The basin is bounded by the Varushanadu hills, the Andipatti hills, the Cardaman hills and the Palani hills on the West and by the Palk Strait and Palk Bay on the East.

• Gundar is a river flowing in the Virudhunagar and Ramanathapuram districts of the Indian state of Tamil Nadu.
• Origin of gundar is Sathuragiri hills and flows through Tirumangalam, Kamuthi ends at bay of Bengal.

• The Vellar River is river in the Indian state of Tamil Nadu. 
• It originates in the Kalrayan Hills, and runs through Salem, Perambalur, and Cuddalore districts, before flowing into the Bay of Bengal near Parangipettai. 
• Source: Confluence of Anaimaduvu River and Thumbal River.

• Left:- Thumbal River, Manimuktha River
• Right:- Anaimaduvu River, Singapuram River, Manjini River, Ellar River, Swetha River, Chinnar River, Anaivari Rive