SALEM/THANJAVUR: Chief Minister C Joseph Vijay is set to open the Mettur Dam for delta irrigation on September 1. The Tamil Nadu government has decided to release water for 45 days, subject to the reservoir’s storage and inflow. The water resources department’s announcement on Wednesday comes as the dam’s water level inches towards the 90-foot mark, which is generally considered an important operating level for commencing release for irrigation.
As of Wednesday evening, the water level in Mettur Dam stood at 89.01 feet with 51,526 mcft of water in storage and inflow of 8,827 cusecs. About 2,000 cusecs of water was being discharged into the river.
The customary June 12 date for opening the dam for delta irrigation was missed this year, as the reservoir did not have the required storage. The inability to release the water on the customary date has already affected Kuruvai cultivation, with the area under the crop in the delta districts estimated to have fallen by around 42,000 hectares.
The decision to release water comes amid demand from farmers’ representatives to the government to open the dam by the second week of September to help them successfully carry out samba paddy cultivation.
The exact operational schedule for the release will be based on the reservoir’s storage and inflow, according to government sources.
West Zone Inspector General of Police R V Ramya Bharathi, Salem Range DIG Santosh Hadimani, and Salem Superintendent of Police S Kuthalingam inspected the dam on Wednesday and reviewed security and safety arrangements.
TN farmers also favour delayed release of water
Salem Collector K Elambahavath inspected the dam and preparatory works for opening the dam. Water Resources Department officials are overseeing cleaning and other arrangements at the dam ahead of the opening.
At the beginning of the 2026-27 irrigation year, the dam had only 41.223 tmcft of usable water. With inadequate inflow from Karnataka reservoirs and the need to maintain a minimum storage of 10 tmcft, release of water for irrigation was delayed.
Historical records show that the timing of the annual release from Mettur Dam has varied considerably depending on storage and inflow conditions. The dam has been opened on the customary date in some years, while releases were delayed in 61 years due to inadequate storage and advanced in 11 years when surplus inflows filled the reservoir early. With the opening being delayed this year, it would mark the 62nd year in which the customary schedule has been missed.
The situation is markedly different from last year, when the dam was opened on the scheduled June 12 date and subsequently reached its full reservoir level of 120 feet seven times during 2025.
P Kalaivanan of the Senior Agro Technologists Forum said the government should consider releasing water around September 10. Kalaivanan said the northeast monsoon would normally become useful only around October 20 and water from Mettur would be required until then.
TN Farmers Association general secretary Sami Natarajan also favoured a delayed release. He said the association had conveyed to the government that irrigation water should be released when the dam level reaches 100 feet.