Cyclone Nada has belied the expectations of good rainfall and contributed only to marginal improvement in the storage of the fast-drying waterbodies that cater to the city’s drinking water needs.
With the available resources said to last only a month, water managers pin their hopes on Northeast monsoon activity that is expected to bring more rainfall in the second week of December. Chennai Metrowater is also mulling over a gradual decrease in daily water supply to deal with impending water crisis.
On Friday, the reservoirs in Poondi, Cholavaram, Red Hills and Chembarambakkam had a storage of 829 million cubic feet (mcft) against their capacity of 11, 057 mcft. Though the reservoirs in Red Hills and Cholavaram received nearly 6 cm of rainfall, it did not translate into much inflow.
The increase in Krishna water supply from the Kandaleru reservoir in Andhra Pradesh now holds the only lifeline to maintain water supply at the rate of 800-830 million litres a day. Officials of the Water Resources Department said the rains in the catchment areas of the four reservoirs brought in an inflow of only 20 mcft, which is hardly sufficient to supply drinking water to the city for a day.
Meanwhile, Poondi reservoir is receiving considerable volume of Krishna water. It realised inflow that is sufficient for two days of water supply, officials said.
With the water level dipping drastically below the level of shutters, Metrowater has started pumping water from the reservoirs in Red Hills and Cholavaram to supply to the city. Large pumps installed along the bund are used to pump out water to the treatment plants.
About 180 mld of water from the Veeranam lake and Neyveli aquifer is being drawn to augment the supply. As a last resort, the water agency plans to draw from nearly 310 agricultural wells in Tiruvallur district to meet the growing needs of the city.
“We have not increased the tanker trips so far. We will decide on decreasing piped water supply depending on the rainfall in December,” said an official.
