CHENNAI: As Tamil Nadu begins to feel the summer heat, water level in 90 reservoirs across the State has gone down by 58 thousand million cubic feet (tmcft) in last two months, show data. “In January, 90 TN reservoirs collectively had 202 tmcft of water. As on March 31, 143.53 tmcft is available in these reservoirs against their total capacity of 224.297 tmcft,” an official said.
“As the summer peaks, water loss due to evaporation will also go up,” he added. According to Water Resources Department’s data accessed by TNIE, while water level in 22 dams has dropped to less than 20 per cent of their capacity, six reservoirs have gone dry.
Among the reservoirs that serve Chennai, Thervoy Kandigai is 100 per cent full and water levels in Red Hills, Chembarambakkam, Poondi and Cholavaram lakes are at 88.85 per cent, 77.61 per cent, 61.84 per cent and 55.41 per cent capacity, respectively.
According to a senior official, though there has been a marginal dip in water level, there is sufficient water in major dams including Mettur (76.73%), Kariakoil in Salem (90.61%), Thunak Kadavu & Peruvari Pallam in Palaghat (99.89%) and Gunderipallam in Erode (98.42%). In 25 of 31 dams in Madurai, water level has gone below 50 per cent, the official said.
Another official said though the State recorded good monsoon, lack of storage facilities forced authorities to release surplus water into rivers and sea. While Chennai’s annual water requirement is 20tmcft, the total capacity of five city reservoirs is only 13.213tmcft.
“We have planned to increase the storage capacity of Poondi reservoir from 3.2tmcft to 5.2 tmcft and construct more check dams on non-ayacut land,” the official said.