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Yesterday, the Supreme Court ruled that Karnataka must release 15,000 cusecs of water daily for the next 10 days to Tamil Nadu - that's nearly twice what Karnataka is currently sharing with its neighbour.
Karnataka has said it will comply only after it receives a copy of the court order and a meeting this evening of leaders of all parties with Karnataka Chief Minister Siddaramaiah of the Congress.
Tamil Nadu says its farmers are in desperate need of the water for the samba or second seasonal crop of the year. Karnataka says Tamil Nadu has already completed one crop cycle, and is now unfairly seeking water for another, whereas its own farmers are struggling.
The Cauvery river, which flows through southern Karnataka and then into Tamil Nadu, has been a point of conflict for decades. Its water was originally divided according to nearly century-old agreements.
Karnataka says it has been given a raw deal. Tamil Nadu says lakhs of acres have come to depend on the water and so its share cannot be reconfigured.
In 1990, the central government created a tribunal to examine the conflict.
In 2007, this tribunal delivered its verdict on how water should be shared between Tamil Nadu, Karnataka, Puducherry and Kerala. However, the states have challenged the divide.
Karnataka says that this year, there has been not enough rain in key catchment areas for the Cauvery as also in the Kodagu district of Karnataka, where the Cauvery originates.
In Karnataka, there are four dams on the Cauvery. The state government says there isn't enough supply in these dams for the drinking water needs of cities like Bengaluru and Mysuru.
The last time the Supreme Court intervened to order Karnataka to increase the supply of water to Tamil Nadu was four years ago.
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