In a few years, old sewer infrastructure in Chennai’s core areas may get a revamp

In a few years, the old and ageing sewer network in Chennai’s core areas, is set to gain a much-needed upgrade.

The final detailed project report to improve the sewer infrastructure in zones covered by two sewage treatment plants (STP) will be ready by February. The report for other zones, which are part of sewage collection system of two other STPs, will be ready by March.

Residents, who had attended the recent meeting organised by Chennai Metrowater, raised concerns about recurring sewage issues in various areas and the need to implement projects at the earliest.

The existing sewer infrastructure that were created over five decades ago, has been in dire need of a revamp to be on par with the rapid urban growth. Last year, the water agency hired Sai Consultants to study the sewer network that has suffered a significant strain over the decades due to sewage generation as it often outnumbered the capacity. The sewage collection network, spread over zones 4,5,6, 8,9,10 and 13, are linked to four STPs in Nesapakkam, Kodungaiyur, Koyambedu and Perungudi.

The officials of the Metrowater said that the consulting firm had presented a draft of detailed project report with recommendations for various strategies to modernise sewer infrastructure and prevent sewage overflow.

The consultant has suggested proposals to replace the existing old pipeline with increased capacity or build new pipelines, improve sewage pumping stations and construct additional pumping stations to suit the projected population in 2060.

It had identified challenges in the infrastructure, including low capacity of sewage pumping stations to handle increasing sewage load, disposal of stormwater in sewer line, haphazard development, network that has outlived its capacity and simultaneous discharge of large quantity of sewage in the network.

While welcoming the move, the residents said that the projects must be accelerated without any delay to match urbanisation in core areas and end perennial issues of sewage blocks and overflow, including in Kodungaiyur and Perambur.

Vasanthi Kannan, secretary, Kodambakkam Residents’ Civic and Welfare Association, said that places like Bazullah Road and North Usman Road in T. Nagar and Rangarajapuram Main Road are some of the chronically affected areas. Many individual houses have given way to apartments in these localities.

V. Sandhya, of Federation of Anna Nagar Residents’ Associations, said that Anna Nagar has been undergoing rapid commercial growth. Many streets in M block are plagued by recurring sewage overflow as the system was designed for smaller population.

The officials said that the projected cost has been estimated to be ₹4,000 crore for the schemes. Once the DPR is finalised, the water agency would get external funding for the projects to be completed in three years. The projects would also mean less pollution in the waterways.