Tackling wastes head on: a Chennai point of view

On April 13 this year, a group of residents gathered in north Chennai to discuss the problems arising out of the first waste-to-energy plant. They were stoutly against the plant. T.K. Shanmugham, president of the Federation of North Chennai Residents’ Welfare Associations, says residents posted their views on social media after Re Sustainability, the company implementing the project, claimed it would not pollute the area. “Groups of residents highlighted experts’ opinion that the project pointed to a class divide between north Chennai and south Chennai,” he says.

“A few months ago, after residents protested, the Greater Chennai Corporation shelved the project to develop an eco-park on 93 acres of the Pallikaranai marsh in south Chennai following bio-mining of the dump there. Most residents in north Chennai are labourers. So they don’t have a voice. Since the Assembly election is due in 2026, we hope the government will listen to the views of residents,” Mr. Shanmugham says. In the past few months, the Corporation took measures to achieve zero waste at the dumps, develop scientific landfill, and facilitate projects for establishing a flawless circular economy in Chennai, which has been grappling with issues caused by unscientific dumping of municipal solid waste.

Not surprisingly, this city’s civic issues highlight the challenges faced by other cities in Tamil Nadu, the most urbanised State with around 50% of the population living in urban areas. Minister for Municipal Administration K.N. Nehru’s announcement in the Assembly this month on waste management in Chennai is a milestone that is expected to shape scientific waste management. Corporation Commissioner J. Kumaragurubaran says the civic body will establish the first waste-to-energy project at Kodungaiyur as part of the integrated waste processing facility. The proposal comprises generating bio-CNG for 550 tonnes per day (TPD), compost plant-1,100 TPD, automated material recovery facilities-1,200 TPD, waste-to-energy plant-1,400 and 700 TPD, and a sanitary landfill-545 TPD. Corporation officials say integrated waste processing facilities will be established at designated locations for processing solid waste collected from Zones 1 to 8 and non-recyclable combustible waste segregated and collected from Zones 9 to 15.

Approval granted

The project will be implemented in the public-private partnership mode and on a design, build, finance, operate, and transfer basis. The contract period is 25 years. The estimated project cost is ₹1,268.38 crore. Administrative approval was granted by the State government in March. Of the two companies, M/s. Delhi MSW Solutions Ltd., a special purpose vehicle of Re Sustainability, was the successful bidder.

A tripartite agreement will be signed among the contractor, the Tamil Nadu Electricity Board (TNEB), and the Chennai Corporation. The power tariff will be ₹6.28 a unit all through the concession period. If the tariff increases in the future, the excess amount will be paid by the contractor to the Corporation. If the tariff decreases owing to unforeseen circumstances, the Corporation will compensate the contractor. Apart from the waste sent to the decentralised processing centres, all unsegregated waste remaining in all zones will be sent to this centralised processing facility. However, with protests by residents against waste-to-energy plants looming, it may be hard for the government and the Corporation to press ahead before the election.

There is no denying that the protesting residents represented a genuine populist surge owing to public health issues near the dumps at Kodungaiyur in north Chennai and Perungudi in south Chennai. The protests are hardly new; the demand has been the same: “Shift the dump to the outskirts and restore the marshland for disaster resilience in a flood-prone city.” Residents around the Information Technology Corridor (Rajiv Gandhi Salai), near the Perungudi dump, have been watching the protests against the first waste-to-energy plant at Kodungaiyur. They will oppose any such project at Perungudi, says A. Francis, president of the Federation of Thoraipakkam Residents’ Welfare Associations.

Revised norms

The Corporation will implement revised guidelines for management of waste from building construction and demolition. The new rules, which will come into force on April 21 this year, are aimed at managing the estimated 1,000 metric tonnes of construction debris generated daily. With these rules in force, unauthorised dumping will come down significantly and timely and traceable disposal of construction and demolition waste will increase within two months, says Assistant Commissioner (Health) Jaya Chandra Bhanu Reddy.

The new system introduces a three-level classification of waste generators. Micro-generators, who produce up to one tonne of construction and demolition waste from minor activities such as household repairs, can deposit the debris free of charge at any of the 15 disposal locations designated by the Corporation. These locations include sites along the Buckingham Canal Road at Sathangadu, the Kodungaiyur and Perungudi dumps, and the old cattle depot at Avadi. Micro-generators can request for collection at the doorstep for a charge through the Namma Chennai mobile application or by dialling the Corporation helpline 1913. Small generators producing between one and 20 tonnes of debris must engage the Corporation-empanelled waste transport operators listed on the Corporation website or arrange for private transport. The Corporation offers collection services to this category at the rate of ₹2,500 per metric tonne. Bulk generators are those producing more than 20 tonnes of waste a day or over 300 tonnes a month. They include demolition sites covering more than 600 square metres or construction sites of over 6,000 square metres. They must transport all waste directly to the designated recycling facilities using their own transport and pay the standard processing charge of ₹800 per tonne through the Corporation’s online portal. In all cases, waste must be taken to one of the two designated processing facilities: the Kodungaiyur dump or the Perungudi dump.

Action against violators

The data released by the Corporation show that between January 1 and April 10, the authorities acted against 284 violators and collected a total of ₹14.20 lakh in penalties. In several cases, vehicles used for illegal dumping were seized. The revised guidelines also outline a structured penalty system. A flat fine of ₹5,000 applies to unauthorised dumping at public space. More severe penalties will be imposed when waste is dumped in storm water drains and waterbodies. In this case, small generators will pay ₹3,000 per metric tonne, while bulk generators will be fined ₹5,000. Any large construction project that fails to comply with the mandated waste management protocol is liable to a daily penalty of ₹25,000, the Corporation has said.

The collection process follows a three-stage protocol: debris is removed from illegal dump sites; the waste is taken to the 15 designated spots in each zone or ‘zonal staging areas’; and then it is transported to the processing units at Kodungaiyur or Perungudi. From January 7 to April 14 this year, the Corporation cleared 1,00,118 tonnes of illegal debris using 201 vehicles. The three-step protocol is tracked through a mobile application, says Mr. Reddy, the Assistant Commissioner. Residents can report violations through the Namma Chennai application or the 1913 helpline.

The Corporation processes 6,150 tonnes of solid waste daily, with construction and demolition debris accounting for 1,000 tonnes. The recycling facilities at Kodungaiyur and Perungudi each have a processing capacity of 100 metric tonnes an hour. Since the start of operations in 2021, these facilities have received 5,20,032 tonnes of construction waste and recycled 4,85,264 tonnes of it, according to a statement.

K. Sundar is a technical advisor at WeStart, the recycling firm contracted by the Corporation. He says, “The multi-step recycling process starts with mechanical crushing to reduce debris into fragments of 25 mm or less. These fragments are then washed to remove non-construction materials such as wood, plastic, and fabric. Hydrocyclone systems are used to separate particles smaller than 75 microns, which are then processed into bricks. Around 85% of the water used in the recycling process is recovered and reused.”

Recycled sand, certified by the Indian Institute of Technology-Madras, is 30% cheaper than the natural sand sold in the market, he says. “The sand is the most sough-after material. It has so far been used for lean concrete or plain cement concrete [cement structures that do not need metal reinforcement] such as the partial foundation for some projects at the Chennai airport, a road-laying project near Anna Salai, and plastering work of a small project at Siruseri.” To curb dust pollution from construction and demolition waste, the Corporation has mandated that all construction sites be properly barricaded. During the transport of construction and demolition waste, vehicles must be fully covered with tarpaulin sheets. Water sprinkling is also mandatory during material handling on-site and at disposal or recycling facilities.

Major problem at Perungudi dump

Leachate discharge remains a major challenge at the Perungudi dump, with untreated liquid waste from both fresh and legacy garbage flowing into the Pallikaranai marsh. The Kodungaiyur dump has an osmosis and sewage treatment plant established by the bio-mining contractors. Mr. Kumaragurubaran, the Commissioner, says long-term scientific measures — like in-situ or off-site treatment — will be developed with the help of experts from Anna University for leachate management. As for the legacy waste, he says that though one of the concessionaires has set up a leachate treatment unit and used the treated liquid as biofuel, the problem persists in portions that are yet to be fully bio-mined by the other contractor.

Senior Corporation officials say solutions are being developed in a 90-acre reclaimed area in south Chennai. Among them are dedicated leachate collection tanks and windrow plants. “A detailed project report is being prepared for the waste-to-energy plant at Perungudi,” says an official.

During a visit to Re Sustainability’s waste-to-energy plant in Hyderabad by The Hindu, engineers claimed that the pollution had come down, thanks to a proven model. “The Chennai waste-to-energy plant is a well-planned facility aimed at reducing the city’s landfill burden while ensuring that waste is treated in an environmentally sound and compliant manner. Built on proven models and adapted to local needs, it is designed to serve the city reliably for decades to come,” says Manoj Soni, Head, Municipal Solid Waste Business, Re Sustainability.

Masood Mallick, MD and Group CEO, Re Sustainability, says, “This transformative waste-to-energy project in Chennai marks a defining step forward in India’s journey towards circular economy principles and sustainable urban living. With Chennai projected to generate over 10,000 tonnes of waste a day over the next three decades, the pressure on land resources is set to intensify. The sites such as Kodungaiyur and Perungudi are saturated. Acquiring additional land for waste dumping is no longer viable — economically, environmentally, or socially. This facility is a strategic response to that challenge.”

“By converting eligible waste into clean energy, recovering organic and inert fractions, and drastically reducing residual volumes, it significantly reduces the burden on landfills. The emphasis is on maximising resource recovery, not indiscriminate dumping or burning of waste,” he adds.