Heavy rainfall in the catchment area of the Poondi reservoir over the past three days has brought in a good inflow into the water body, which is a storage point for the city’s drinking water supply. This has come in handy at a time when it is drying up.
On Friday, the Poondi reservoir received an inflow of 935 cubic feet per second (cusecs), enough to supply water to Chennai for three days. Nearly 650 cusecs flowed into the reservoir, thanks to 7 cm of rainfall in the catchment areas.
The remaining water was from Kandaleru reservoir, Andhra Pradesh, provided under the Krishna water supply project.
Poondi reservoir, which is spread over 34.58 sq.km., and used for fishing, is now filled to less than one-third of its total capacity, which is 3,231 million cubic feet of water (mcft). Residents of Thirupachur and Pandur, villages near the reservoir, said the lake bed near their homes had dried up a few days ago.
The parched lake bed has led to a slight decrease in the groundwater level.
Rainfall for the past few days has provided a momentary relief, said a resident of Thirupachur.
Officials of the Water Resources Department said lack of rainfall combined with a substantial volume of water being discharged from the reservoir brought down the storage level to 635 mcft. The lake bed has dried up only in the foreshore area, which borders Thirupachur and Movur, they added.
Of the last 10 years, eight years have seen water storage in the reservoir dwindle below 1,000 mcft in the month of August. However, this did not affect the drinking water supply, except during the drought in 2003.
With currently available resources, daily water supply to the city can be maintained until the end of the year. “We now transmit water to the reservoirs in Red Hills and Chembarampakkam from where water is drawn for city supply. About 1,000 mcft is drawn from the reservoirs in a month,” said an official.
While all the water in Red Hills and Chembarampakkam reservoirs could be drawn upon for drinking water supply, a minimum storage of 10 mcft is required at the water body in Poondi, as it is used for fish-rearing, an official said.