THANJAVUR: The copious rains during the northeast monsoon and the steady flow of water in the Cauvery river system have enabled 386 irrigation tanks of the total 764 in the delta region to now reach full capacity as against 42 tanks three months ago. Moreover, 329 irrigation tanks have attained more than 75% of their capacity.
The Cauvery delta districts of Thanjavur, Tiruvarur, Mayiladuthurai and Pudukkottai have a total of 737 system tanks, fed by rivers and their canals, besides rainwater, and 27 non-system tanks which are dependent solely on rainwater. At 561, Thanjavur district has the highest number of such tanks, followed by 170 in Pudukkottai.
While there are 28 tanks in Tiruvarur, Nagapattinam has three tanks and Mayiladuthurai, two. As most of these tanks are in the tail-end areas, the water stored in the tanks is used for paddy cultivation, particularly during samba season. Normally, these tanks get more water during September and October. The continuous flow of water in the rivers, especially in the Grand Anaicut and the Vennaru, this year, however, led to a majority of the tanks to reach more than 50% of their storage capacity by the end of August itself.
This was partly due to Cauvery water from the Mettur dam being released on the customary date of June 12. Since then the dam attained full storage level seven times, courtesy the surplus water released into the Cauvery by Karnataka. Further, normal rainfall recorded in Thanjavur district during the southwest monsoon this year and the above normal rainfall recorded during the northeast monsoon between October 1 and December 11 contributed to the comfortable storage in the tanks.
As on December 10, 386 tanks have reached full storage capacity. Another 337 tanks have water between 75% and 99% of their capacity while 31 have attained 50% to 75% of their capacity, and five tanks between 25% and 50%. Meanwhile, K A Koothalingam of Pallathur said the recent rains have contributed to the increase in the water level in the tanks.
"Besides being useful for cultivating standing samba crop, the water in the tanks will be available in the coming summer for cattle. It will also lead to an increase in the groundwater level in the region," he added.