People on the leeward side of the Karnataka-Tamil Nadu border argue that there are international conventions if not a treaty on sharing of water flowing between two riparian countries along the flow of a river. These principles apply with equal force to intra-country disputes as well.

But those on the other side argue that there needs to be a better understanding on the part of people in Tamil Nadu during years of deficient rainfall. Commentators and newspapers in their editorials too have spoken of the need for greater sensitivity when it comes to sharing water in the years of a deficient rainfall.

But the latter argument is at best, disingenuous, and at worst, completely false. Whether it is a surplus year or a deficient one in meteorological terms, the Karnataka government has followed a simple policy. Release the water when the dam waters are in surplus and keep the shutters resolutely down till the full reservoir level is reached.

If this is the practice every year, to talk in terms of water release practices that distinguish between deficient and surplus monsoon years is meaningless. After all, it can be nobody’s case that the monsoon is uniformly deficient or surplus. Politically too, it cannot be any other way. No matter who the chief minister is, it just doesn’t seem credible that political opponents would allow the person to get away with releasing water under any contingency other than when the dam surpluses.

Stated in simple terms, the sharing of water is a property dispute. To whom does the rainwater that falls in the Cauvery river basin (up to the borders of Karnataka, that is) belong? Karnataka says it is the exclusive owner of all the water that falls in its geographical area. Tamil Nadu claims it is the joint owner and so is entitled to partake of its share at the same time as Karnataka.

If Karnataka’s claim that it is the exclusive owner of all the freshwater that annual rainfall brings is to be accepted, then any water that flows into Tamil Nadu is an act of trespassing and whoever is responsible for this should pay compensation. It is like if your neighbour’s dog poops on your front yard or bites a child in the house, the former should not only pay compensation in civil damages but also take steps to rein in such trespasses in the future.

In the event, Karnataka had better take all steps to ensure that not a drop of water flows into Tamil Nadu as a logical corollary of its claim to exclusive ownership of Cauvery water from the catchment areas belonging to it.

This is not such an outlandish proposition as it may seem at first. Under the Indus Waters Treaty between India and Pakistan, India is actually able to use all of the water from the rivers Ravi, Sutlej and Beas thanks to an extensive canal network in Punjab and Haryana. But of course, given the nature of the topography of the Cauvery basin that is going to be a tough ask, not to speak of the current climate in the country where every project gets bogged down with execution challenges from all sorts of project-affected people.

So, a more realistic option would be for Karnataka to recognise that Mettur dam is a water warehouse and pays warehousing charges for the quantum of water that belongs to it but has strayed into Tamil Nadu. As water is stored in the Mettur dam there is an investment cost (Mettur dam) which has to be recovered. Since water that is stored spreads out to subsume fertile lands surrounding it, one can impute a value of rent computed as derived from the best possible alternative use of that land. Then there is recurring cost of supervising the stored water.

But above all, there is a need to redesign an actuarial model to cost the risk of flooding if, despite the best efforts at storage, there is excess inflow in an odd year and water has to be released all of a sudden that destroys agricultural fields and properties in the plains downstream. Karnataka needs to pay for that as well. But all this would apply only to the storage season — June-May — of every year. When it starts to rain the following year, Tamil Nadu must, of necessity, be allowed to use up the surplus from the previous year as otherwise it would not be able to create fresh capacity for storage of rainwater on behalf of Karnataka, accruing in the next year.

On the other hand, if Tamil Nadu wants to use it during the course of a monsoon year then it must pay for such water usage.

But this is not such a serious issue. We are talking about a bilateral monopoly (single buyer and single seller). Even in such a market structure, buyer and seller arrive at a consensus price. Corporate mergers are a classic case involving one buyer and one seller and synergy gains from such a merger are shared among shareholders of both the companies. So it can be done.

The incremental agricultural output must be apportioned to all factors of production including a value attributable to a farmer’s physical and managerial efforts besides a share for the factor input of the State’s farm extension service. A share of what remains as a surplus must be credited to Karnataka’s account.

To sum up, the terms of an alternative settlement could be roughly along these lines: that Karnataka agrees to pay warehouse charges (as a logical extension of its proprietorial claims over the water) and Tamil Nadu must agree to share synergy gains from agricultural value added if it wants to consume the water in the same crop year. One suspects Tamil Nadu would want to, as it doesn’t make sense not to use the available water at the most productive season for cultivation.

Thus, there is a two-way flow of revenue — one based on a stock measure (stored water varying with times) and the other, a revenue flow in the opposite direction (quantity of water that Tamil Nadu will use in the same crop year). The values of the respective claims of the two States need not be expressed in monetary terms alone. It is possible to convert such monetary claims to value of agricultural output and further in terms of embedded quantum of water in such agricultural output? Perhaps the existing Tribunal award itself would make it revenue-neutral. But that would be ironic, wouldn’t it?