Residents have complained that rainwater mixed with sewage was released into the Korattur lake through the supply channel from Ambattur following overnight rain on Tuesday.
S. Sekaran, secretary, Korattur Aeri Padukappu Makkal Iyakam (KAPMI), a citizen’s group in the locality, said the newly constructed regulators were opened near DTP Colony and Ondiveeran Koil Street to release rainwater mixed with sewage into the lake.
This happened even as the Water Resources Department had been desilting the lake ahead of northeast monsoon, he said. Residents demanded steps to prevent release of sewage into the lake and they said regulators should not be used to pollute the lake.
Officials said the regulator was opened to let in water only when the supply channel from Ambattur carried heavy flow during rainy days. This would otherwise lead to inundation for 4-5 km in the surrounding areas before the water reache Otteri Nullah. Greater Chennai Corporation would have to plug the sewage outfalls in the channel, they said.