Cauvery Delta Tanks Rebound as Monsoon Rains and Mettur Releases Increase Water Security

Strong monsoon rainfall and sustained Cauvery inflows have rapidly refilled irrigation tanks across Tamil Nadu’s Cauvery delta, strengthening farm prospects and groundwater recharge.

The Cauvery delta in Tamil Nadu has greatly improved water storage across irrigation tanks. Farmers received major help ahead of the strongest agricultural season of the northeast monsoon's heavy rainfall and the Cauvery River system's continuous inflows supply for cattle over the summer, and support in recharging groundwater levels.

 Three months ago, there were just 42 irrigation tanks in the delta region; currently 386 of the 764 tanks have achieved full capacity. Another 329 tanks have filled to more than 75 percent of their capacity, indicating a substantial recovery in the availability of water across the agricultural belt.

There are 737 system tanks supplied by rivers and canals in the Kaveri delta districts of Thanjavur, Tiruvarur, Mayiladuthurai and Pudukkottai, in addition to 27 non-system tanks that are completely dependent on rainfall. With 561 tanks Thanjavur has the most followed by Pudukkottai with 170, Tiruvarur with 28, Nagapattinam with three and Mayiladuthurai with two.

Representatives assigned the early improvement to continuous water flow in key channels such as the Grand Anaicut and Vennaru along with the timely release of Cauvery water from the Mettur dam on June 12. Since the Mettur reservoir has reached full storage levels seven times, supported by surplus inflows from Karnataka.

Water storage throughout the delta was further reinforced by above-average northeast monsoon rainfall from October 1 to December 11 and enough southwest monsoon rainfall in the Thanjavur district.

At present, just five tanks are still in the 25% to 50% range, 337 tanks are between 75 percent and 99 percent capacity, and 31 tanks are between 50% and 75%. The Cauvery delta region's total water security is anticipated to be improved by the increased storage, which will support standing samba crops ensure water supply for cattle over the summer, and aid in recharging groundwater levels.