The inflow of Krishna river water to Chennai has been increasing over the past few days. Officials of the water board expressed confidence that this will help meet Chennai’s drinking water needs.
The total capacity of the five lakes that are the main water sources supplying Chennai—Poondi, Cholavaram, Puzhal, Chembarambakkam, and Kannankottai—is 11,757 million cubic feet. On July 9, these five lakes together had only 5,956 million cubic feet of water in storage. However, due to insufficient inflow, the water storage has fallen to 5,222 million cubic feet as of Sunday. This is 44.42 percent of the total capacity.
Not enough rain
This year, during the southwest monsoon season, rainfall has been below normal by 6 percent in Chennai, 67 percent in Chengalpattu, and 23 percent in Tiruvallur. As a result, the main reason for the drop in water levels in the lakes is that there has not been enough rainfall in the catchment areas.
In this situation, the inflow of Krishna river water from the Kandaleru reservoir in Andhra Pradesh has increased.
As of Sunday morning, 442 cubic feet of water per second was flowing in at the Kandaleru-Poondi canal entry point. This plays a key role in filling the lakes that supply drinking water to Chennai.
Water board officials said: Chennai city requires 1 TMC of drinking water per month, while there is currently a reserve of about 5 TMC of drinking water. Similarly, the Veeranam lake has a reserve of 343 million cubic feet of water. Drinking water is being supplied from there to the southern and southwestern parts of Chennai.
Likewise, through the 3 desalination plants operating at Minjur and Nemmeli near Chennai, 200 million liters of drinking water are being supplied every day to the areas under the Chennai Corporation.
Arrival of 1 TMC of water
In addition, the Krishna river water being released from Andhra Pradesh’s Kandaleru reservoir is currently reaching Poondi Lake. As of Sunday, 442 cubic feet of water per second was flowing in. With the southwest monsoon intensifying in Andhra Pradesh, the inflow of Krishna river water is also expected to increase further.
The Krishna river water reaching Poondi Lake is also released to the Chembarambakkam and Puzhal lakes based on Chennai’s drinking water requirements. Through this, Krishna river water is stored in all three lakes — Poondi, Chembarambakkam, and Puzhal.
Water reserve for 6 months is available
Since last July until now, about 1 TMC of water has reached Chennai through the Krishna River. This will meet one month’s drinking water requirement for the Chennai metropolis. Since the southwest monsoon is expected to continue until the end of September, the inflow of Krishna River water is expected to increase further.
Therefore, there is currently enough drinking water reserve for the next 5 to 6 months. In addition, the northeast monsoon, which primarily brings rain to Tamil Nadu, is set to begin in another 3 months. During the northeast monsoon, there is a possibility that the drinking water reservoirs will be filled completely again. Hence, for now, there is no chance of a drinking water shortage in Chennai, they said.
