Faeces and other dirt flow into the Muthannan lake. The sewage flows after the Coimbatore Corporation diverted it from the underground drainage network near Gandhi Park. The lake is one among the eight the Corporation took over for maintenance from the Public Works Department.

Enquiries with the civic body reveal that the sewage flows through the storm water drain into the lake from the site where it has taken up underground drainage repair work on Thadagam Road, near the Park.

The Corporation undertook the work after it discovered that the 30-year-old sewerage system carrying the waste had almost collapsed. The pipelines were too damaged to be repaired and the earth above it had caved in for more than 10 feet, sources say. It is in the process of replacing the pipelines.

The work has been going for almost a week, says M.S. Velmurugan, councillor, Ward 57. “Soon after the work had begun, the sewage has been flowing into the lake. And it passes through the storm water canal, on both sides of which people of Kumarasamy Colony live.”

People say the stench is unbearable. “It is impossible to live in the midst of flowing filth,” complains B. Manoharan, a resident.

The residents are more or less surrounded by filth because the drain carrying the waste is to their east and on the south is the Muthannan lake. The problem does not end there.

Mr. Manoharan says the water supply pipeline is next to the open drain and if the water were to be contaminated, the consequences will be unimaginable.

Mr. Velmurugan says the water supply pipeline caters to around 2,000 families that live along Sundapalayam Road.

The civic body sources say that the work will take another four days to complete and until then, they have no option but to divert the water through the storm water drain.

Commissioner T.K. Ponnusamy says he will check with his engineers and ensure that the pollution of the lake is stopped at the earliest.

Health Committee Chairman P. Nachimuthu says he will enquire into the incident.