The Water Resources Department on Sunday evening stopped discharging water from the four city reservoirs.
As the inflow to the reservoirs in Poondi, Cholavaram, Red Hills and Chembarampakkam had decreased, the release into the surplus course had been suspended, according to WRD officials.
Only about 660 cubic feet per second (cusecs) was being drawn from the reservoirs to meet the drinking water needs of the city. The storage in the four reservoirs is nearly 95 per cent of their capacity of 11,057 million cubic feet (mcft), an official said.
The department began releasing water from the Poondi reservoir on December 4 in view of the heavy inflow. Shutters of the other three waterbodies were opened subsequently.
Nearly 800 mcft of water, equivalent to one month's of water supply to the city, was released into the surplus course from the water bodies up to Sunday.
The quantum of Krishna water discharged from Andhra Pradesh has also come down. On Monday, the entry point of the Kandaleru Poondi canal in Uthukottai received only 240 cusecs of water.
Chennai has realised 3,420 mcft of Krishna water since the release from Kandaleru reservoir began in early October. This is sufficient to maintain over three months of drinking water supply, the official said.