Chennai: The water levels in the city’s five reservoirs have plummeted by about 42% compared to the same day last year, raising concerns over the city’s drinking water security. Officials said evaporation and percolation losses would consume nearly 30% of the stored water, leaving even less for daily piped supply.As of Tuesday, the reservoirs have 4,569 million cubic feet (mcft); about 42% lower than the 7,853 mcft recorded last year.A senior Metrowater official said the position was better than in 2024, when the reservoirs held 3,817 mcft on Sept 29. This year’s storage is 752 mcft higher. He added that the city’s two desalination plants are meeting requirements of the city.Metrowater is drawing 80.43 million litres a day (MLD) from the 110 MLD plant and 51.13 MLD from the 150 MLD plant, both at Nemmeli on East Coast Road. Drawal from the smaller plant is down from 82.91 MLD last year, while that from the larger plant has risen from 41.66 MLD. However, Metrowater is distributing 1,273 MLD to consumers, 53 MLD more than at this time last year.“When water levels dip in the reservoirs, desalinated water comes in handy to fulfil the city’s requirement,” the official said.A third desalination plant, with a capacity of 450 MLD, is under construction and is expected to become operational by March next year. The official said dependence on reservoirs could fall once it is commissioned.Despite the shortfall, Metrowater expressed confidence that Chennai would not face a situation like the 2018 crisis.The picture is grimmer outside the piped network. I Annadurai of Thangam Bore Wells said the groundwater table has dried up in several localities, particularly in the southern and western parts of the city beyond Guindy, where Metrowater supply is patchy. Demand for new bore wells has risen as a result, he said.
