Rapidly depleting groundwater levels are casting a long shadow over kuruvai (summer paddy) cultivation in Tamil Nadu's Cauvery Delta, with farmer groups warning that the region is unlikely to meet its target of 3.5 lakh acres under the crop this season. The crisis, centred around Tiruchi and surrounding Delta districts, has been compounded by the delayed opening of Mettur Dam — traditionally unlocked on 12 June for irrigation — leaving most Cauvery-dependent farmers with no surface water to rely on.

Scale of the Groundwater Crisis

A recent survey by the Water Resources Department (WRD) found that groundwater levels across all Delta districts recorded a steep decline during May, raising serious concerns about the sustainability of irrigation through the critical agricultural season. The findings have alarmed farmer leaders, who say the situation is deteriorating faster than seasonal norms would suggest.

Of the roughly 21 lakh borewells used for agricultural irrigation across Tamil Nadu, nearly 14 lakh functional pump sets are concentrated in the Delta region alone, according to Cauvery Farmers Protection Association president V. Dhanapalan. With surface water unavailable, this borewell network has become the last line of defence for kuruvai cultivation — but it is under severe strain.

Power Cuts Add to Farmers' Burden

Effective borewell irrigation requires at least eight hours of uninterrupted electricity to irrigate a single acre of farmland, Dhanapalan said. Erratic power supply across the Delta has made that benchmark nearly impossible to meet, compounding the water scarcity challenge for cultivators who have already abandoned surface-water irrigation.

Farmer leaders describe the combination of falling groundwater tables and unreliable electricity as a pincer squeeze that is shrinking the cultivable area week by week. Only a limited number of borewell-equipped farmers have proceeded with kuruvai this season, and even they are reporting mounting difficulties.

What the Monsoon Can — and Cannot — Fix

The India Meteorological Department (IMD) has forecast a favourable southwest monsoon for the region. However, Dhanapalan cautioned that rainfall alone may not be sufficient to restore depleted aquifers in time. Groundwater levels in the Delta traditionally recover only when the Cauvery and its distributaries flow at full capacity, enabling water to percolate gradually and recharge underground reserves — a process that requires sustained river flow, not just surface rainfall.

This distinction is critical: even a good monsoon season may not translate into aquifer recovery if the Cauvery does not run at adequate volumes through its distributary network.

Samba Season Also at Risk

The immediate concern is kuruvai, but farmers warn the consequences could extend well beyond this season. If groundwater is not replenished before the samba cultivation cycle begins — the Delta's principal paddy season — the region could face severe agricultural distress. The Cauvery Delta is one of Tamil Nadu's most important rice-producing belts, and a back-to-back failure across kuruvai and samba would have significant food security and livelihood implications for farming communities across multiple districts.

With the WRD survey data now in the public domain, pressure is mounting on state authorities to address both the power supply irregularities and the broader question of groundwater governance in the Delta before the situation becomes irreversible.