Pattali Makkal Katchi district secretary Ashok Srinithi, along with party members, submitted a petition to the District Collector on Friday, seeking steps to stop the discharge of untreated sewage into River Noyyal and other water bodies in the city.

They said water samples collected from the Noyyal earlier this year were sent for laboratory testing. Based on the test results, they alleged that the Coimbatore Corporation was releasing untreated sewage into the river. They also alleged that wastewater from the Coimbatore Medical College Hospital was being directly discharged into Valankulam Lake.

“The laboratory tests showed high faecal coliform levels in the water. Experts have said it could take more than 50 years for the water bodies to recover,” Mr. Srinithi said.

He alleged that despite repeated complaints, no concrete measures had been taken to prevent sewage from mixing with the Noyyal and other water bodies. The petitioners demanded action within 45 days, failing which they said they would organise a protest.