As many as 142 blocks out of 385 in Tamil Nadu are overexploited with respect to underground water, according to N Varadaraj, Regional Director, Central Ground Water Board, Chennai.

Eight blocks were saline and other blocks had been classified as critical and semi-criticial. The Government had taken up a scheme for the maintenance of tanks in the state, he told newspersons yesterday.

To a question, he said a sum of Rs 500 crore had been allotted for artificial recharging of nearly 12 lakh dug wells in the state.

Out of this, Rs 100 crore was released for taking up recharging of 3.5 lakh wells.