Chief Minister C. Joseph Vijay has initiated the release of water from the Mettur Dam for delta irrigation. While the government aims for a 45-day initial release, low reservoir levels and monsoon deficits pose a significant challenge.
- CM C. Joseph Vijay opened the Mettur Dam gates on September 1, 2026.
- Current water level is 91.56 ft with storage at 54.45 tmc ft.
- The government plans a 45-day release, contingent on inflows from Karnataka and the upcoming monsoon.
In a critical move for the agricultural heartland of Tamil Nadu, Chief Minister C. Joseph Vijay opened the Mettur Dam (Stanley Reservoir) on Tuesday, September 1, 2026, to facilitate irrigation for the delta region. The timing is crucial as the 'Samba' cultivation season is underway, and any delay in water reaching the tail-end of the river system—which typically takes three weeks—could lead to widespread crop failure.
As of Tuesday, the reservoir's water level stood at 91.56 ft, with a current storage of 54.45 thousand million cubic feet (tmc ft). For context, the dam's maximum capacity is 93.47 tmc ft with a full reservoir level of 120 ft. Given the current storage and accounting for a 10 tmc ft reserve for drinking water and environmental flows, the state can sustain the current release rate of one tmc ft per day for approximately 45 days, assuming no further inflows.
BozokMedia analysis reveals a worrying trend in water realization. During the 2026-27 southwest monsoon, there has been a staggering shortfall of 57.246 tmc ft compared to the quantum stipulated by the Supreme Court in its 2018 judgment. This deficit places the state in a precarious position, making the management of existing stocks a high-stakes balancing act between immediate irrigation needs and long-term security.
| Month (2026) | Stipulated Quantum (tmc ft) | Realised Quantum (tmc ft) | Shortfall/Surplus |
|---|---|---|---|
| June | 9.19 | 2.915 | -6.275 |
| July | 31.24 | 0.7138 | -30.526 |
| August | 44.4677 | 24.0229 | -18.069 |
The state government is now banking on September inflows. Historical data over the last 30 years shows an average September realization of 36.8 tmc ft. However, with a 47% monsoon deficiency in the Cauvery catchment, officials expect only about 20 tmc ft. If this target is met, the water release could be extended by another two weeks.
"The decision to release water now is a calculated risk to prevent a total collapse of the Samba crop cycle in the delta regions."
Historically, even in the driest years since 1974, September has yielded at least 10 tmc ft (e.g., 10.57 tmc ft in 1987). This historical floor provides a slim margin of safety for the administration. The ultimate hope now rests on the Northeast Monsoon, expected to arrive around October 20, which typically provides half of the state's annual rainfall.
1. What is the current water level of the Mettur Dam?
As of September 1, 2026, the water level is 91.56 ft with a storage of 54.45 tmc ft.
2. Why was the water released immediately?
It takes three weeks for water to reach the end of the river system; delay would have severely damaged the Samba crops.
