Low Reservoir Levels Put Tamil Nadu At Risk Of Water Shortage

UPDATE - follow-up to T.N. may be heading towards a water crisis, unless northeast monsoon comes to the rescue: Tamil Nadu faces a serious threat of water shortage and lower rice production as total storage in the major 15 irrigation reservoirs stands at only about a third of their combined capacity, a sharp drop from 92% during the same period last year.

Current Status

The State's largest dam, Mettur, holds about 24.7 thousand million cubic feet of water, which is barely enough to maintain releases of one tmcft a day to farmers in the Cauvery delta for more than a week. Moderate rainfall has brought 248 mm from October 1 to November 8 against an anticipated 236 mm, but the State needs at least 260 mm more, mostly in November, to feel comfortable. December typically yields only about 20% of the monsoon total. The Tamil Nadu Agricultural University previously predicted 438 mm for the season, close to the normal 434 mm, while the Meteorological department stated rainfall would likely be normal for the southern peninsular region.

Crop Impact And Demands

Farmers have planted paddy for the samba-thaladi season across roughly 3.62 lakh hectares in the Cauvery delta, with nearly 50% using the direct-sown method due to water limits. Non-delta areas show a bigger strain, with paddy coverage down by 1.3 lakh hectares compared to last year. Across the State, direct sowing accounts for 57% of coverage, up from 39% previously. In the 2025-26 period, total rice production reached 77.5 lakh tonnes, down from the peak of 79.07 lakh tonnes in 2021-22. To protect delta crops, the State government asked the Cauvery Water Regulation Committee and the Cauvery Water Management Authority to have Karnataka release about 20.7 tmcft, which includes a 16.9 tmcft backlog. However, the Authority approved a lower recommendation of 3.88 tmcft at 3,000 cusecs per day for 15 days starting November 7, 2026.

Context

Water storage levels in major irrigation reservoirs directly dictate how long farming operations can continue without relying heavily on active monsoon rainfall or inter-state river releases. Direct sowing is a common drought-coping farming practice where seeds go straight into unflooded soil to save water when traditional transplantation is not viable.