CHENNAI: Nine days of persistent rainfall have added enough water to Chennai’s reservoirs to meet the city’s drinking water needs for another 28 days, with combined storage in six major waterbodies rising by nearly 1 TMC since October 15.

The storage increased by 984.98 million cubic feet (mcft), from 4,485.68 mcft on October 15 to 5,470.66 mcft on October 24. The reservoirs now hold 41.38% of their combined capacity of 13,222 mcft, providing a significant boost to the city’s drinking water security as the northeast monsoon intensifies.

The Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) supplies 1,237.71 mld, including 61.29 mld for industries, bulk consumers and municipal needs. Besides the 968.41 mld sourced from the reservoirs, the board draws 200 mld from the two desalination plants, 28 MLD from quarries, 16 mld from wells and borewells, 14 mld from sources in added areas and 5 MLD from Porur.

The additional storage is equivalent to about 28 days of the city’s current water supply of 1,237.71 million litres a day (MLD), according to calculations based on the volume of water added.

The CMWSSB draws 968.41 MLD from the six reservoirs, accounting for nearly 78% of the city’s total supply. The remaining water comes from two desalination plants at Nemmeli, quarries, wells and borewells, sources in added areas and Porur.

Among the six reservoirs, Red Hills recorded the highest increase, with storage rising by 539 mcft from 1,876 mcft on October 15 to 2,415 mcft on October 25. It is now at 73.18% of its capacity of 3,300 mcft.

Chembarambakkam’s storage increased from 1,319 mcft to 1,497 mcft, while Veeranam rose from 526.68 mcft to 677.56 mcft. Poondi’s storage increased from 412 mcft to 490 mcft and Cholavaram from 120 mcft to 144 mcft. Kannankottai-Thervoy Kandigai recorded a rise from 232 mcft to 247 mcft.