Cholavaram reservoir, Chennai
A poor monsoon so far has left reservoirs with 48% less water than they held at this time last year, while groundwater levels are about 45% deeper. The city’s five principal reservoirs, Poondi, Cholavaram, Red Hills, Chembarambakkam and Kannankottai-Thervoy Kandigai, held 4.79 thousand Million Cubic Feet (tmcft) on Thursday, compared with 10 tmcft on the same day last year. That is 41% of their combined capacity of 11.75 tmcft. Including Veeranam, storage totals 5.71 tmcft, down from 10.93 tmcft, a drop of nearly 47%. The average depth rose from 3.77m in Oct 2025 to 5.48m in Oct this year, a fall of 1.71m, or 45%. Madhavaram recorded the sharpest fall, from 5.80m to 10.81m, followed by Thiru-Vi-Ka Nagar, where levels dropped from 4.57m to 8.82m. On Wednesday, the 110 million litres a day (mld) and 150mld plants supplied 100mld and 87mld, respectively.
“If the situation does not improve, we might have to consider rationalising water supply, while relying on desalination plants,” an official said. Metrowater says desalination will cushion the shortfall. By Feb, the Minjur plant, which has a 100mld capacity, will yield at least 20mld,” a senior official said. “We are confident of handling the situation,” he said.
The city is running low on water, both above and below ground. Metrowater is looking to the sky for relief, hoping for more rain until mid-Dec. Groundwater levels also dipped. However, levels across the city improved by nearly a metre from last month. By Thursday, the supply rose to more than 100mld in both plants. “Both the Nemmelli plants can be operated at full capacity.
Evaporation from the soil and water lost through plants, together called evapotranspiration, would be very high in summer. You Can Also Check: Gold Rate in Chennai | Silver Rate in Chennai | Bank Holidays in Chennai | Public Holidays in Chennai | Chennai AQI | Weather in Chennai | Petrol Price in Chennai | Diesel Price in Chennai | CNG Price in Chennai | LPG Price in Chennai Stay updated with the latest Chennai news.
But that has not been the case so far,” said S Janakarajan, a retired professor at the Madras Institute of Development Studies (MIDS). “Water extraction will be much higher than groundwater recharge,” he said, hoping the coming cyclones would bring some relief to the reservoirs. Janakarajan said the state govt lacked a water security plan despite several warnings about El Niño. It is a lazy way out by the govt and harms the coastal ecosystem,” he said. Sekhar Raghavan, Chennai’s ‘Rain Man’ and founder of The Rain Centre, an NGO, said residents should not wait for the state to supply water. “By this time, Chennai should have had at least 140 cm of rainfall, but we received only 110 cm as of Nov 10,” he said. In many places, builders have not constructed the systems properly, yet the CMDA approved them,” he said. “But enforcement will not improve without outside monitors,” he said. “Second, the govt must draw up a preventive plan before a drought or flood strikes, and it must involve experts with decades of experience,” he said. “Both floods and droughts are man-made,” he said.
However, water experts are not so optimistic. They warn that the situation is worrying and the offered solution is dangerous. “Surplus rain was expected this year. “Chennai receives an average of 120cm of rainfall every year. Desalination plants can never be the solution. They should recharge groundwater themselves. Join conversation Share your thoughts in the comments Be respectful · TOI community guidelines The govt must act on two fronts. “First, appoint third-party monitors for rainwater harvesting. TVK govt relaunched its rainwater-harvesting initiative. “Officials and engineers are not enough. The govt must change its attitude and seek outside expertise. “If govts do not learn from experience, the same problems will recur, and we will keep having the same discussions with no change. Download the TOI App.