Delta farmers in Tamil Nadu have raised serious doubts over whether the Mettur reservoir's current storage of 52.33 thousand million cubic feet (TMC) — with the dam level at 89.72 feet as of Friday evening — will be sufficient to sustain the state government's proposed 45-day water release for the samba cultivation season. The Tamil Nadu government has announced that the dam will be opened on 1 September, with Chief Minister C. Joseph Vijay scheduled to inaugurate the release in person.

What the Numbers Say

For Cauvery water to reach tail-end irrigation areas, farmers say a daily discharge of between 15,000 and 20,000 cubic feet per second (cusecs) would be necessary. At the current storage levels, farmers contend this rate of release cannot be sustained for the full announced period. An estimated 268.47 TMC of water is required to irrigate 12.10 lakh acres across the delta districts between 15 September and 28 January — a figure that underscores the scale of the shortfall concern.

A Season Already Under Stress

The anxiety over samba comes on the heels of a severely disrupted kuruvai cultivation season. Traditionally, the Mettur dam is opened on 12 June each year to support kuruvai paddy. This requires the dam level to be at or above 90 feet. At the start of June this year, the level stood at only 79 feet, forcing authorities to skip the customary opening date. Farmers dependent on Cauvery water could not undertake kuruvai cultivation, while those with access to groundwater proceeded independently. As a result, the area under kuruvai cultivation fell sharply — from 5.66 lakh acres last year to 3.78 lakh acres this year, a decline of roughly 33%.

The Monsoon Factor

Compounding the concern is inadequate rainfall during the Southwest monsoon season. Farmers and agriculture observers are now looking anxiously toward the Northeast monsoon, expected to set in towards the end of October, but there is no certainty over whether it will bring sufficient inflows to replenish the reservoir in time. The thirteen Cauvery delta districts — including Thanjavur, widely regarded as Tamil Nadu's rice bowl — are heavily dependent on Mettur dam water for irrigation, leaving little buffer if monsoon inflows disappoint.

Farmers Urge Two-Week Delay

In view of the storage deficit and monsoon uncertainty, farmer groups have formally suggested that the dam opening be postponed from 1 September to 15 September. They argue that a two-week delay would conserve existing storage and help bridge the gap until Northeast monsoon inflows begin to augment the reservoir. The state government has not yet indicated whether it will reconsider the announced date, and preparations for the 1 September inauguration are reportedly continuing as planned.

What Happens Next

With Chief Minister Vijay's visit to the dam site scheduled for 1 September, all eyes are on whether the government will announce any revision to the release plan or address farmers' concerns about storage adequacy. The coming weeks — and the Northeast monsoon's performance — will determine whether the samba season can recover the ground lost during a difficult kuruvai cycle.