On July 28, the Cauvery Water Regulation Committee met for the 139th time and did what such committees do in a deficient monsoon. It ordered Karnataka to release 3,500 cusecs of water a day to Tamil Nadu at Biligundlu, for fifteen days. The Cauvery Water Management Authority ratified the order two days later at an emergency sitting. Karnataka complied on paper and barely at all in practice - inflows at Biligundlu between July 29 and August 2 ranged between 158 and 550 cusecs, a fraction of what had been directed. On August 3, Tamil Nadu's newly elected Chief Minister, the actor-turned-politician C. Joseph Vijay, sent the state to the Supreme Court asking it to enforce the CWMA's order and to monitor Karnataka's reservoirs every ten days.
None of this is unfamiliar. What is worth noticing is the size of the gap between what each side calls a lawful entitlement. Tamil Nadu told the Court that, applying the pro-rata formula to the season's improved inflows, it was actually owed 26.954 TMC - nearly six times the 4.536 TMC (3,500 cusecs for fifteen days) the CWMA had ordered. Karnataka, for its part, pointed to a cumulative monsoon deficit of roughly 30–35 per cent and to farmers in its own command area who had not yet been able to sow. Both figures can be defended within the same legal framework. That, more than either state's stubbornness, is the real story of Cauvery 2026.
India settled who owns the Cauvery's water a long time ago, most authoritatively in the Supreme Court's 465-page judgment of 16 February 2018 in State of Karnataka v. State of Tamil Nadu. What it has never settled and what resurfaces every deficient year in almost identical form is: who absorbs the shortfall when the river does not deliver the water the entitlement assumed it would. Karnataka and Tamil Nadu are no longer really fighting about the law of allocation. They are fighting, repeatedly and expensively, about the law of scarcity -a body of law that barely exists.
The numbers on the table were fixed by the Cauvery Water Disputes Tribunal's final award of 2007, which assessed the basin's yield in a normal year at 740 TMC and divided it: 419 TMC to Tamil Nadu, 270 TMC to Karnataka, 30 TMC to Kerala, 7 TMC to Puducherry, with the rest reserved for environmental flow and outflow to the sea. The 2018 judgment revised this only with little changes. It gave Karnataka an additional 14.75 TMC - 10 TMC on account of Tamil Nadu's unaccounted groundwater, 4.75 TMC for Bengaluru's drinking-water needs ,taking Karnataka's share to 284.75 TMC and Tamil Nadu's to 404.25 TMC, and it reduced Karnataka's annual release obligation at Biligundlu from 192 to 177.25 TMC. It also directed the Union government to build an implementation mechanism, which got crystallized as the CWMA and CWRC under the Cauvery Water Management Scheme, 2018.
These bodies do genuinely useful technical work: the CWRC assesses inflows and storage and recommends a release schedule; the CWMA, drawing its members from the Union government and the party states, approves or modifies it. Their directions are not decrees of a court, but the Supreme Court has for some years treated their technical judgment as close to dispositive as in September 2023 a three-judge bench declined to substitute its own view for what it called the combined expertise of the CWRC and CWMA on a distress-sharing question, and something similar looks likely if the present petition is heard on merits. That deference is not obviously wrong; judges are not hydrologists. But it exposes exactly where the 2018 judgment left a gap. The Tribunal's award and the Court's affirmation fixed entitlements calibrated to a "normal" year assessed on a fifty-per-cent dependability basis. Neither instrument prescribed a formula for what each state's share should be when actual inflow runs well below that baseline. Into that vacuum has stepped a set of expert regulators empowered to recommend numbers case by case, at emergency meetings, under time pressure, with no published, binding rule that either government can rely on before the crisis begins. Tamil Nadu's pro-rata claim and the CWMA's cusec-based order are not, in that sense, competing violations of one clear rule - they are two defensible readings of a situation the rule was never written to reach.
This is also why the language of "cooperative federalism," which both governments used at their respective all-party meetings this month, sits uneasily with what actually happens. Article 262(2) of the Constitution allows Parliament to bar the ordinary courts from an inter-State water dispute altogether once a tribunal has been constituted, and Parliament did provide for one, under the Inter-State River Water Disputes Act, 1956. Yet neither that Act as it has operated here, nor practice since 2018, has kept the Supreme Court out of the picture. If anything, settling entitlements in 2018 made the Court's continuing, near-annual supervisory jurisdiction over implementation the load-bearing part of the machinery. Karnataka and Tamil Nadu do not resolve distress-year disagreements between themselves, or even primarily before the CWMA; they resolve them by escalating to Delhi, as both did again this month. That is not cooperative federalism functioning as designed - it is coercive adjudication doing the work cooperation was supposed to do, on a near-annual cycle, because the underlying rule for sharing scarcity was never written down.
The Mekedatu balancing reservoir dispute is the same argument wearing concrete. Karnataka says a 66.5-TMC reservoir near the two states' border, cleared in principle by its own Cabinet years ago and now awaiting a revised Detailed Project Report due to the Centre by mid-August, would let it store water in good years and comply more reliably with its release obligations in bad ones. Tamil Nadu's objection is not really about the project's 400 MW of power, or even Bengaluru's drinking water; it is about who gets to decide, unilaterally, what "distress" looks like once the water sits behind an upstream dam rather than in a shared river. Its Chief Minister wrote to the Prime Minister this July, after a Union minister told the Rajya Sabha that the 2018 judgment does not require Karnataka to obtain downstream consent before building at Mekedatu, asking that the statement be withdrawn. The Supreme Court has already declined, more than once, to block the project at the DPR stage, leaving the substantive questions to the CWMA and the Central Water Commission -the same technical bodies that already carry, unaided by any codified drought formula, the burden of deciding scarcity-sharing every July.
The gap is fixable without another round of tribunal litigation. First, the CWMA holds regulation-making power under the 2018 Scheme that it has barely used to pre-commit to a transparent drought formula - a published, proportionate-reduction rule, based on a real-time inflow at Biligundlu against the fifty-per-cent dependability baseline, that both states could calculate for themselves before the next emergency meeting rather than dispute cusec by cusec in July. Second, the recurring factual fight over what water actually reached Biligundlu - again at the centre of Tamil Nadu's August petition - needs a single, jointly-verified feed rather than competing state figures placed before the Supreme Court each year. Third, any future storage infrastructure in the basin, Mekedatu included, should have its drought-year release protocol fixed and made binding by the CWMA before construction clearance. It should not be left to be litigated after the concrete is poured. Fourth, Parliament could use its Article 262 power more fully than it has, to make a codified CWMA distress formula statutorily binding in the way the 1956 Act's ouster clause was originally intended to make tribunal awards binding - removing the incentive, visible again this August, to treat the Supreme Court as the real regulator of drought years.
None of this will make a dry monsoon wetter, or persuade either state's farmers that the other side's hardship is real. But the pattern is now old enough, and repeats often -2002, 2012, 2016, 2023, 2026. Everytime, It can no longer be explained as bad luck or bad faith on one side of the border. Plethora of discussion took place about the legal architecture for deciding who owns the Cauvery. But it was never decided who loses when the Cauvery falls short of what the law assumed. Every basin in India governed by a rainfall-dependent tribunal award : the Krishna, the Godavari, the Mahanadi, rests on the same unexamined assumption. Karnataka and Tamil Nadu are simply the first, and by now the most practised, in finding out what happens when it fails.
Author is an LL.M Scholar at GNLU. Views are personal.