Overflowing landfills put Chennai’s marshlands and water table at risk

Chennai is brimming with mixed solid waste. Of course, so are most other metros in India. But Chennai’s per capita waste, around 0.7 kg per day, is the highest in the country. According to statistics from the Greater Chennai Corporation (GCC), the city generates 6,150 metric tonnes (MT) of waste per day. Of this only 15% of wet waste and 12% of dry waste is processed. The remaining is dumped in landfills at two sites: Perungudi and Kodungaiyur, both with high residential populations.

The choice of the landfills is a big reason for concern, warn environmental experts. With Chennai’s undulating topography, these are low-lying marshlands that function as wet sponges to absorb the excessive rainwater and works to mitigate inundation. These marshlands have been carrying waste for at least two decades. The decomposition is polluting both the water table underground and air above it. “There are multiple layers of waste—legacy electronics, metals, heavy metals like lead, textile waste, and plastic, the biggest culprit of all.

These decomposing materials react with the microorganisms in the landfill and result in emission of poisonous gases,” says Srinath Iyer, environmental planner and consultant. He adds that legacy waste needs immediate action because it presents the opportunity to control new waste generation.

“To reduce landfilling, the GCC should focus on decentralising waste collection solutions and processing infrastructure, re-channelising the waste to reach the processors and back into the economy,” says Siddharth Hande, founder and CEO of Kabadiwalla Connect, a waste management solutions provider.

From thoughtful generation to disposal

The GCC has been consolidating the city’s waste at these landfills while trying to come up with a solution. But rapid urbanisation and growing consumerism are accelerating the pace of waste generation. By 2030, Chennai’s urban population is projected to double, and the amount of waste generated will also increase correspondingly. Moreover, the Chennai pin code area is huge—suburban districts such as Kanchipuram, Chengelpet, and Tiruvallur with lesser waste management infrastructure also add to Chennai’s waste volumes. Still, no clear solution is in sight.

Experts are of the view that this is largely because public engagement is lacking. Chennai’s waste is not sorted thoroughly at source. A discarded object turns into waste only after six hours. A lot can be done to turn it into constructive waste in that six-hour window. Even recyclable materials lose value if they are not sorted at source and recovered. According to the GCC’s rules, waste generators must store the segregated waste in appropriate bins—green for wet and blue for dry and hand them over to authorised collectors. Garbage collection is privatised in 10 zones in Chennai, while the GCC oversees waste in five zones. The collection at zones from 9 to 15 are outsourced to Urbaser Sumeet and Ramky Enviro Engineers.

When it comes to waste disposal, it is all about the mix. As much as 60% of the waste in Chennai is organic wet waste that is biodegradable. The inert mix that needs incineration constitutes the remaining 40%. Among this, low-value plastic and textile waste are challenges.

Though planning for collection and transportation is in place for Chennai, the micro composting centres or facilities do not have a comprehensive management plan. There is no clarity as to whether the sorted waste needs to be composted, recycled, sent to biogas plants, or dumped in landfills. “The GCC collects only two types of waste. Where does the hazardous waste comprising of needles, glass, band-aids, razors, and expired medicines come in?” asks Bhuvana Raj, co-founder of SIMPLE, a sustainability initiative.

Dumping in landfills should be the absolute last resort, says Krishnapriya A., co-founder, Spreco Recycling. But what happens on the ground is the opposite. “Outsourced vendors are not charged with Request for Proposal (RFP) charges on the basis of recovery, but as a tipping fee—the more they dispose in the landfill, the more they are paid.”

Local and hyper-local solutions

Sustainable community drives should be built for localised collection and recycling. This will instil habit, trust, and lasting awareness and go beyond the rhetoric of reduce-reuse-recycle, to repurpose and retrofit too.

But collection is expensive. Who would bear the burden of the cost? The GCC is already charging a fee from residential, commercial, and institutional generators. This is where the informal collectors come into play. These informal waste collectors collect and sort the waste, handing it over to scrap shops, kabadiwallas, and material recovery facilities (MFR) who pre-process for recyclers. Informal waste collectors divert 25% of the waste away from landfills. For every tonne they collect, they save `20,000 for the GCC.

This hyper-local network needs to be leveraged and optimised to solve collection and sorting issues, says Hande of Kabadiwalla Connect. “Their work should be facilitated by bringing them under safe spaces, scheduling their collection, and removing the unsafe aspect. With aggregation and quality checks at these levels this can be derisked and replicated,” he says.

“Moving away from bureaucratic centralisation, NGOs and SHGs should be partnered in the task. An official announcement or directive alone is not enough to incite action,” says Srinath.

Dealing with hazardous waste

Over the years, along with volume, the composition and complexities of waste have been changing. Single-use plastic generation in Chennai, according to data from 2022, is around 9.5%, e-waste is 9% and textile waste is close to 30%. Thanks to consumerism, all three are climbing steadily.

Plastic and textile waste do not degrade. Recycling and channelling the products that are already in use back into the economy is the best way to turn waste into a resource and prevent them from polluting the environment, says Krishnapriya from Spreco Recycling.

“Recycling is how we take these persistent materials and turn them into sustainable alternatives such as Paver blocks, other construction products, table-top items from plastic and toys, and thrift-store materials from textiles,” says Krishnapriya. Spreco has also come up with a mobile plastic recycle unit (a plug-and-play model) that can be installed in villages. “Rural women can recycle and sell the products and make a livelihood out of them,” she says. Though the GCC has separate collection centres for hazardous e-waste, most of the e-waste in Chennai is handled by informal collectors.

Using data as a tool

In place of directives and enforcements that have not initiated any action so far, incentivisation is an effective way to involve stakeholder engagement. For both segregation and disposal efforts, the public should be rewarded in their digital wallets, bonus articles through the Public Distribution System, or a property tax discount for bulk generators, say experts. Of course, a little will go a long way. Data should be used in setting the KPIs or metrics for the selections. At the collection end, data should be collected on the volume of waste, locations, transportation, destination reached, and details of management. This data will also throw light on the loose ends, gaps, and help planners arrive at appropriate solutions and streamline operations. Traceability will also lead to accountability.

Different stakeholders will use the data differently for solutions.

From government offices to privately-managed spaces, shops, and push-carts—everything should be made zero-waste destinations. At the manufacturers’ level, extended producer responsibility or EPR—a policy where manufacturers are held responsible for the entire lifecycle of their products and packaging—should be made mandatory. Products should come with a feasible plastic alternative, a clear life cycle and ways to be absorbed into the same system. Data on diverse types of products in use and if they are compostable, or recyclable is needed.

The need for innovative solutions

The R&D for managing waste has only reached as far as in bio-mining as a solution for legacy waste. A recent study that reported about the presence of microbes and microbial enzymes that can dissolve plastic at the dump sites in Chrompet and Perungudi is yet to gain momentum.

Instead of investing a lot, the GCC should look at implementing simple, micro solutions and scaling and replicating those, says Raj of SIMPLE. “Big waste generators and think tanks should come up with solutions to close the collection-disposal-recycling loop. Simple solutions that need less space and resources are needed,” she adds. For instance, SIMPLE has managed 50MT of waste in the past five years.

“When there is someone to collect waste from the doorstep, and report back on how it is responsibly used, people are ready to participate in collection drives. We have had 16 such collection drives in Mandeveli Raja Street since January 2025 organised by Kabadiwalla Connect, thus diverting 2,360 kg of recyclables for recycling. Our WhatsApp group is growing with steady enrolment from residential and commercial members,” says Ganga Sridhar, Founder,

EcoKonnektors Trust, a community-driven non-profit organisation.

“Waste management is in our cultural DNA. We just need to derisk collection. Even small sandboxing pilots hold potential,” says Hande.

“We need to manage waste to save ourselves. Nature can save itself,” Srinath says.