Tamil Nadu registered around 47 cm rainfall during October-December against the expected 45 cm. This marked a departure of 5% for the period up to December 30, according to the meteorological department.
In the last three months, nine districts received excess rainfall, while 16 districts registered normal rainfall with positive departure.
Besides the relatively favourable rainfall, the State realised a higher amount of Cauvery water than its share during the period between June and December. Around 195 tmc ft was realised on the inter-State border, as measured by the Central Water Commission. This was about 30 thousand million cubic feet (tmc ft) more than its due, though it was not so high as it was during the previous year.
The present combined storage of reservoirs is about 20 tmc ft less than what it was at the end of 2019. This was due to the storage of the Mettur dam, which was around 91 tmc ft a year ago. But, on Friday, the dam’s storage was 71.8 tmc ft. Water managers expect that about 15 tmc ft more will have to be released in the next few weeks, and when the shutters are brought down, the storage is expected to be around 55 tmc ft. Likewise, another 15 tmc ft will have to be released from the Bhavanisagar dam for irrigation. In the southern districts, Papanasam and Manimuthar are having extremely comfortable storage. The only sore point is the Vaigai, which has about 3.3 tmc ft against the capacity of 6.091 tmc ft.
Around 30% of the irrigation tanks are full, compared with 23% a year ago. Likewise, the storage of around 41% of the tanks is 90% and above, while the figure for 2019 was around 36%.
The managers are confident that Chennai’s drinking water needs can be easily met in the coming months as the storage of all the reservoirs is, on an average, around 90%. Until Friday, about 5.2 tmc ft of Krishna water was received from Andhra Pradesh.