Nearly 60% of the irrigation tanks in Tamil Nadu are not even half-full, despite the State receiving around 33 cm of rainfall in the last two months.
Of a total of 14,139 tanks, the storage in 8,230 tanks ranges from nil to 50%. Three districts — Madurai, Sivaganga, and Pudukottai — account for 3,533 tanks with poor storage. Madurai, despite recording a surplus rainfall of 27% in October and November, has 1,069 tanks under this category. The total number of tanks in the district is 1,340.
In Sivaganga district, which has 1,351 such tanks, there has been no surplus rainfall. Yet, it has registered a positive deviation from the normal.
In other words, till now, it has received 35 cm of rainfall against the anticipated amount of 34 cm.
Though it is too early to identify reasons with respect to poor storage, one of them could be the encroachments on, or obstructions in, the channels supplying to the tanks.
However, there is nothing surprising about Pudukottai, which has 1,113 such tanks, as the district received 16% less rainfall than the anticipated amount.
Two other districts — Thanjavur and Tirunelveli — have about 530 tanks each, with a storage of up to 50%. Like Madurai, Tirunelveli received surplus rainfall, at 47%. Yet, 537 of the 780 tanks in the district have poor storage.
But, in respect of Thanjavur, the situation is understandable as it is a deficit district in terms of rainfall with a departure of -33%.
Otherwise, Kanniyakumari, which has recorded 79% excess rainfall in the last two months, is comfortably placed with 1,832 of its 2,040 tanks having a storage ranging from 51% to full (100%).
It accounts for almost one-fourth of the tanks in the State with full storage.
Chengalpattu and Ramanathapuram, both famously called “Eri Mavattangal” (tank districts), share the honours with the southernmost district as their tanks (489 and 429 respectively) have storage ranging from 51% to 100%.
