Draft project report to help improve old sewer infrastructure in Chennai’s core areas likely to be ready by October

The old sewerage infrastructure that often faces recurring complaints in Chennai’s core areas may be improved in a few years. The draft report of the study that was commissioned to assess the existing condition of the sewer network is set to be ready by October.

In a bid to improve the sewerage system on par with the rapid growth in the metropolis, Chennai Metrowater had hired Sai Consultants to study the network that is over six decades old in the city, covering 174 sq.km. and spread over zones 4,5,6, 8,9,10 and 13.

The consultant would have to identify the chronically-affected areas and recommend improvements essential for optimum efficiency of the infrastructure. Officials of the Metrowater said the consultant would evaluate the condition of the network in each zone — from sewage generation to disposal practices and reuse of treated sewage in the zones.

The study would focus on modernising the sewage collection system linked to sewage treatment plants in Perungudi, Koyambedu, Nesapakkam and Kodungaiyur. At present, about 580 million litres of sewage is collected in core parts everyday. With the completion of projects, the network would be able to carry an additional 200 mld of sewage.

Metrowater’s sewerage infrastructure comprises of pipelines running for a length of nearly 2,879 km, including pumping main lines, 221 pumping stations and 92,378 machine holes. The water agency would take decisions, including on building new pumping stations and enlarging the capacity of the sewer lines to suit the projected population in 2060 based on the report of the study.

Residents of Vedagiri Street in Chinthadripet, often complain of receiving drinking water mixed with sewage. | Photo Credit: RAGU R

Residents of various parts of the city, including Chintadripet, noted that the sewer lines needed a revamp. Sewage mixing in drinking water is a recurring complaint in streets like Vedagiri Street and Mangapathy Street in Chintadripet. This occurred even after sewer lines were partially replaced.

Officials of the Metrowater said the consultant would have to suggest specific solutions to inadequacies in the sewage collection and also on sites needed for new facilities.

The interim report has projected the estimated cost to be around ₹1,771 crore for the projects. Nearly 60% of the sewage pumping stations and lines and 28% of the machine holes are likely to be replaced to address issues in chronically-affected areas. Localities such as Kodungaiyur, Saidapet and K.K.Nagar would largely benefit from the scheme.

The projects would also mean less pollution in the waterways. About 1,000 sewage outfalls in Adyar, Cooum rivers and Buckingham canal is likely to be plugged apart from arresting sewage overflow into stormwater drains.

Tenders would be called for after the detailed project report is ready. Funding tie-up needs to be decided after which work would commence during the next fiscal and would be completed in four years, an official added.