Mettur Dam: the Water Source for Tamil Nadu’s rice belt

The Mettur Dam, located in Salem district of Tamil Nadu, serves as the primary water source for the rice belt in the delta districts. Every year, water is released from the dam on June 12 to facilitate timely irrigation for the paddy crop. However, due to poor monsoon conditions, the release has been delayed this year and will commence on September 1, 2026, under the leadership of Chief Minister C. Joseph Vijay.

With the water level at nearly 90 feet, the dam will release water for approximately 45 days, which is crucial for the rice cultivation. Construction of the Mettur Dam began in 1925 and was completed in 1934, involving a workforce of 17,000 workers. Residents of Nayambadi and nearby villages were displaced during the construction process, but remnants of the old Christian Church and the Nandhi of the Jalagandeeswarar temple can still be seen today when the water level recedes.

The dam, constructed across the Cauvery River to manage water supply for irrigation and hydroelectric power generation, was designed by Colonel W. M. Ellis and built under the supervision of an Irish engineer, Vincent Hart. The funds for the dam's construction were sourced from taxes collected in the Madras Presidency, with Sir C.P.

Ramaswamy Iyer as the head of the Board of Revenue. With a maximum height of 214 feet and width of 171 feet, the Mettur Dam possesses a total length of 1,700 meters and a maximum water level of 120 feet, holding a capacity of 93.47 tmcft. The reservoir covers an area of 42.5 square kilometers and receives inflows from its own catchment area, as well as the Kabini and Krishna Raja Sagar (KRS) Dams in Karnataka.

Approximately 16.05 lakh acres of agricultural land in 12 districts, including Tiruchi, Thanjavur, Tiruvarur, Cuddalore, Nagapattinam, Erode, Pudukkottai, Ariyalur, Perambalur, Karur, Mayiladuthurai, and Namakkal, benefit from the water released from the Mettur Dam. The scheduled opening date for water release is June 12, while the dam is closed on January 28 every year, ensuring a total of 230 days of water availability annually for these districts.

A total of 330 TMC is required for irrigation purposes, with 16.05 lakh acres of agricultural land in the mentioned districts benefiting from the released water.