Setting up a Cauvery Management Board or Authority, as suggested by the Tribunal, on the lines of the Bhakra Beas Management Board is perhaps the only way to ensure that the dispute doesn’t repeat itself like a stuck record whenever rainfall is deficient.

A good monsoon may be unpredictable. But the fallout of a bad monsoon isn’t, at least in Tamil Nadu and Karnataka.

When the rains fail in the two states, this is what happens, more often than not: There would be little water in the Cauvery. Crops whither and farmers suffer. Then Tamil Nadu demands that Karnataka, the upstream state, should let go of some water, instead of holding on to it. Karnataka demurs. Where is the water to release, it asks. Then comes a bandh or two in Tamil Nadu over Karnataka’s rejection. And it kicks up protests in Karnataka against the possibility of the state giving away water. Tamil Nadu rushes to the Supreme Court.

That’s what happened once again in the last 10 days. And that’s how once again the Supreme Court came entered the scene on Friday.

The court asked Karnataka to consider giving Cauvery water to Tamil Nadu to help that state continue to "exist as an entity". Adjourning the case to Monday for a detailed hearing on Tamil Nadu’s petition for water, the court left Karnataka in no doubt that the state would end up releasing at least some water to its neighbour. Karnataka must make it clear to the court on Monday how much water it could part with.

If there was a formula to share the water, Karnataka was bound by it, said Justice Dipak Misra, and he advised Karnataka to "live and let live". That left Tamil Nadu Chief Minister Jayalalithaa with a little smile on her face and sent Karnataka Chief Minister Siddaramaiah into a huddle with his officials.

Met our legal advisor, senior jurist Mr.Fali S Nariman in Delhi and held discussion. Our advocates will argue in the SC on Monday #Cauvery — CM of Karnataka (@CMofKarnataka) September 3, 2016

As has been the pattern again, the final ruling of the court in the latest episode is likely to leave either of the states or both unhappy. If the court orders the release of a substantial quantity of water, Karnataka will be tense. And if that quantity falls far short of Tamil Nadu’s demand, farmers there will take to streets.

On 26 August, Tamil Nadu wanted the court to order Karnataka to release 50.052 tmcft (thousand million cubic feet) of water. This is the amount of water which it says Karnataka failed to release since 1 July. Karnataka said its reservoirs had only 51 tmcft available for use and, if it let go of it, its own crops would die and there won’t be water to drink for people in Bengaluru and two other towns. Tamil Nadu claimed that Karnataka has more water than that and is “diverting” part of it to “undeclared” projects.

But who must find how much water there really is? And who must decide how it should be shared, if there isn’t enough water for both states?

The Cauvery Water Dispute Tribunal said in its 2007 verdict that the Centre must set up an authority to independently monitor and regulate water availability and releases. If this is still waiting to be implemented, it’s because the politics of parties take precedence over the economics of suffering farmers. In the face of claims and counter-claims, the parties in power at the Centre from 2007 till now had no wish to do anything that might incur the wrath of farmers — key votebanks — in one state or the other.

Politics thrives on human misery. Consider this: When water is scarce, even half-a-tmcft of it can cause a riot, in Karnataka if it’s released and in Tamil Nadu if it isn’t. Reservoir levels go low, and tempers run high, because millions of farmers in both states depend on the river. But even as the Cauvery basin goes dry for crops, it turns fertile for politics. Frenzied rhetoric makes the problem worse than what it is.

No wonder that the Cauvery dispute has taken as many turns as the river takes twists on its course through the two states. Originating at Talakavery in Karnataka’s Kodagu district, the Cauvery traverses about 322 kilometres, enters Tamil Nadu near Hogenakkal in Dharmapuri district, zigzags for 483 kilometres more before joining the Bay of Bengal at Poompugar in Nagapattinam district of that state.

At the root of the dispute is Tamil Nadu’s claim that Karnataka’s dams on the river impound more water than they should and stop it from flowing down. Karnataka argues that Tamil Nadu has been not only usurping more water but even wasting it with “unscientific” agricultural methods, letting a good amount of it into the sea.

The backstory

In the Indian context, there are essentially three kinds of “water rights”. First comes the “riparian right”. It’s the people’s fundamental right to use the water flowing on the land they live on.

Karnataka’s contention is that Tamil Nadu had resorted to “prior-appropriation” of Cauvery water and that the British made it possible. The state says the British favoured the Madras Presidency as against Mysore, then ruled by a king.

Then there is the “prior-appropriation right”: appropriate more water first and claim it as your right later. This means Territory-A uses more water before Territory-B gets a chance to do it and, when a dispute crops up later, lays claim to it as its legal share. This sounds suspiciously similar to a squatter’s right to land, but it isn’t really as bad or illegal. People who have used the water first have already invested in dams and are irrigating their lands, and they do earn some right over its continued use.

The third one, the “equality right” is what Territory-B fights for, accusing Territory-A of usurping more water by prior-appropriation. Territory-B wants an “equitable” share for itself. (Similar to the prior-appropriation right, there is also the “prescriptive right”, acquired by long usage of water at a time when existing laws allowed it.)

Karnataka’s contention is that Tamil Nadu had resorted to “prior-appropriation” of Cauvery water and that the British made it possible. The state says the British favoured the Madras Presidency as against Mysore, then ruled by a king.

The trouble first arose in 1881 when Mysore wanted to build a dam across the Cauvery, and Madras objected to it. The British arbitrated, and the result was an agreement in 1892, followed by another in 1924. But the dispute went on and on, and in 1990 came the Cauvery Water Disputes Tribunal which, after 17 years of fierce deliberations, came up with an award in 2007.

The Tribunal allocated 270 tmcft of water to Karnataka, 419 to Tamil Nadu. Kerala (which has a Cauvery tributary) and Puducherry (which is near the end of the river) were given 30 and seven tmcft respectively. These allocations were made on the basis that the Cauvery has a total of 740 tmcft of water “at 50 per cent dependability”, which means that the river has this much of water in 50 out of 100 years.

The Tribunal said that Karnataka should release 192 tmcft of water to Tamil Nadu in every “water year” (from June to May), and that’s what becomes contentious when the rains fail. The Tribunal also said that, during bad monsoon, the states must share the “distress” in the proportion of their normal allocations.

But in the absence of an effective mechanism to ensure a proportionate sharing of the “distress”, the dispute rages on.

Is there a permanent end to the dispute?

A permanent solution was what the Tribunal was thought to have found after 17 years of deliberations. It’s a question of implementing it — in distress years. When rains are copious, the states have little problem in sharing the water. Setting up a Cauvery Management Board or Authority, as suggested by the Tribunal, on the lines of the Bhakra Beas Management Board is perhaps the only way to ensure that the dispute doesn’t repeat itself like a stuck record whenever rainfall is deficient.

Equally important is to find ways to save water and increase inflows into the river.

A Rs-1,000-crore proposal that Tamil Nadu had in 1974 to modernise its irrigation system could save up to nearly 50 tmcft of water, but it has been hanging fire for lack of funds. And the demand of the state’s farmers to desilt Cauvery channels has had no takers either. Reason: lack of funds.

On its part, Karnataka could tap at least part of the huge amount of rain water that falls over Western Ghats and simply flows into the ocean into a network of pipes and let it into the Cauvery, experts point out.

Would Narendra Modi be large-hearted enough to investigate and fund such projects in both the states?