Here's a timeline of events in the Cauvery Water Dispute:
The origins of the dispute over the sharing of Cauvery waters date back to the agreements of 1892 and 1924 between the then Kingdom of Mysore and the then Madras Presidency.
In 1990, the central government created a tribunal to examine the conflict and address the water shortage.
17 years later in 2007, this tribunal delivered its verdict on how water should be shared between Tamil Nadu, Karnataka Kerala and Puducherry. All states challenged the share assigned to them.
An appeal was filed against the 2007 order of the Cauvery Water Tribunal that allocated, in a normal year, 270 TMC, or thousand million cubic feet, 192 TMC to Tamil Nadu at its Mettur Dam, 30 TMC to Kerala and 6 TMC to Puducherry. Karnataka wanted Tamil Nadu's share to be slashed by half and had made a strong case on drinking water needs of Bengaluru and Mysuru.
In 2012, the Supreme Court intervened and ordered Karnataka to increase the supply of water to Tamil Nadu. Later when Tamil Nadu filed a suit against the dip in water supply, Karnataka government said that there wasn't enough water supply in the four dams on the Cauvery to cater to the drinking needs of Bengaluru and Mysuru and it was unfair on part of Tamil Nadu to ask for more water.
As situation became tense between the two states, the Supreme Court intervened again in 2016 and directed Karnataka to release 15,000 cusecs of water daily for a period of 10 days (September 7 -September 16) to Tamil Nadu. After Karnataka's interim petition, it modified the order on September 12 and directed Karnataka to release 12,000 cusecs of water daily till September 20. This triggered massive protests in Karnataka.
In October, 2016, after attempts to resolve dispute through arbitration failed, the Supreme Court had asked the centre to form the Cauvery Management Board but the government declined, insisting that only parliament could create such a body. The top court asked Karnataka to release 2000 cusecs of Cauvery water per day to Tamil Nadu till further orders.
On July 5, 2017, the Supreme Court allowed Tamil Nadu to file a fresh plea alleging that Karnataka was not giving its due share of Cauvery water.
In January 2018, the Supreme Court indicated that it would deliver its verdict within a month on the decades-old Cauvery water dispute, saying enough confusion has been created on it for over two decades. The top court said that any forum could touch the matter relating to the Cauvery basin, only after it gave its verdict in four weeks.