Tamil Nadu recorded the lowest Cauvery realisation in a 14‑year span during the 2026 southwest monsoon. In the last four months the state received 44.208 thousand million cubic feet (tmc ft), far below its 123.14‑tmc‑ft quota for the period, creating a shortfall of roughly 79 tmc ft. The 2023‑24 monsoon saw a similar low of about 45 tmc ft, and this year’s figure marks the fourth lowest realisation since 1974‑75, when provisions of the 1924 Tamil Nadu‑Karnataka Cauvery agreement were due for review.
The Mettur dam, from which irrigation releases began about a month ago, holds 36.639 tmc ft of water in a capacity of 93.47 tmc ft. An allowance of 10 tmc ft is set aside for drinking water, environmental flows and dead storage. At the current discharge rate of 15,003 cubic feet per second (1.2963 tmc ft per day), the dam’s storage would last roughly 18 days.
Farmers and water experts warn that the prospects for paddy coverage during the samba‑thaladi cultivation season are bleak unless the northeast monsoon brings relief. Meanwhile, Karnataka has protested the Cauvery Water Management Authority’s (CWMA) release order. Between September 24 and October 4, Tamil Nadu received about 3.35 tmc ft, while CWMA had directed Karnataka to provide 5.18 tmc ft over 15 days.
In the Cauvery delta, paddy coverage has fallen to 1.68 lakh acres, down from 2.64 lakh acres in the same period last year. Direct sowing accounts for about 1.27 lakh acres, indicating farmers are adapting to the water shortage. Cuddalore and Tiruvarur districts together cover 72% of the delta’s paddy acreage, with 52,700 acres in Cuddalore and 68,400 acres in Tiruvarur. The delta’s coverage last year reached 2.64 lakh acres and eventually 13 lakh acres, while the current year’s target is nearly 12.7 lakh acres, which may not be fully met under the present conditions.
