Delhi’s mounting waste crisis | Explained Premium

As the national capital, Delhi needs to scale up its processing capacity to manage daily waste. The quantity of waste is expected to increase in the coming years together with the per capita waste generation

Rag pickers seen collecting items at the Bhalswa landfill in New Delhi on December 16, 2020. | Photo Credit: SHIV KUMAR PUSHPAKAR

The story so far: The Supreme Court’s recent criticism of solid waste management (SWM) in New Delhi highlights a critical issue. The national capital has more than 3,800 tonnes per day (TPD) of solid waste remaining untreated. This waste reaches landfills and threatens public health and the environment.

What is the status of Delhi’s SWM system?

According to the 2011 Census, New Delhi’s population was about 1.7 crore, which in 2024 is expected to be around 2.32 crore. Considering an average per capita generation of about 0.6 kg/day per person, the city generates approximately 13,000 TPD of waste — roughly 1,400 truckloads — which adds up to about 42 lakh tonnes per annum. The city’s population is expected to rise to 2.85 crore by 2031, so waste generation could go up to 17,000 TPD.

About 90% of the waste generated in the city is collected by the three municipal corporations: the Municipal Corporation of Delhi (MCD), Delhi Cantonment Board, and the New Delhi Municipal Corporation. Generally, about 50-55% of the waste generated in Indian cities is biodegradable wet waste; 35% is non-biodegradable wet waste; and 10% is an inert component. Accordingly, 7,000 TPD would be wet waste; 4,800 TPD dry waste; and 2,000 TPD inert.

What about the processing capacity of SWM in Delhi?

New Delhi has waste-processing facilities at Okhla, Bhalswa, Narela, Bawana, Tehkhand, SMA Industrial Area, Nilothi, and Ghazipur. These facilities have a collective design capacity of about 9,200 TPD. This includes composting facilities handling around 900-1,000 TPD and waste-to-energy projects of 8,200 TPD.

However, the MCD is disposing of unprocessed waste of 3,800 TPD in the three designated landfills: Gazipur, Bhalswa, and Okhla. These landfills, consisting of unprocessed wet and dry waste, generate methane gases, leachates, and cause landfill fires, adversely affecting the surrounding environment. The accumulation of unprocessed waste in these landfills has led to a staggering 2.58 crore tonnes of legacy waste piling up over 200 acres of land. The MCD initiated biomining to reduce the amount of waste in 2019, but the COVID-19 pandemic halted these efforts. Initially planned to be completed by 2024, this task will take another two to three years.

However, the environmental impact will persist until fresh waste is scientifically processed. With the current accumulation of 3,800 TPD of unprocessed waste, the landfills will only become bigger and taller.

What are the MCD’s challenges?

The MCD faces several challenges in tackling waste within the city. One major issue is the lack of waste segregation at source. Many households and commercial establishments don’t do this. As a result, unprocessed mixed waste enters landfills. Additionally, waste processing plants need large land parcels, of about 30-40 acres each, which is a challenge in Delhi. This challenge in turn leads to a significant portion of waste being left untreated.

Public awareness of proper waste management practices is also lacking, contributing to littering and improper disposal habits, which divert the MCD’s attention towards clearing open points rather than processing wet waste.

Lack of regular waste collection services in certain areas also add to the buildup of waste as well as littering, while illegal dumping in open areas and water bodies increases the pressure on the municipal body, warranting more resources for clean-up.

Finally, a lack of coordination among various stakeholders — including multiple municipal corporations — results in inefficient waste management, further complicating the MCD’s efforts to address the city’s waste management issues.

What efforts need to be made in order the separate the waste?

As the national capital, Delhi needs to scale up its processing capacity to manage daily waste. The quantity of waste is expected to increase in the coming years together with the per capita waste generation. With this in mind, the MCD should design a waste-management plan to cater to about three crore people while the total design capacity of the city’s waste processing facility should be 18,000 TPD.

Biodegradable wet waste should be composted or used to generate biogas. The design capacity of the wet-waste-processing system should be set at 9,000 tonnes. Typically, the capacity of composting facilities is around 500 tonnes per day, which means Delhi will need at least 18 composting or biogas plants to ensure no biodegradable wet waste reaches landfills. This will demand significant efforts from the MCD: to identify land, set up composting facilities, and operate them.

As for the non-biodegradable dry waste: about 2% will be recyclable, and this can be sent to recycling facilities. The remaining 33% won’t yet be recyclable. The non-recyclable dry waste fraction is called refuse-derived fuel (RDF) and consists of plastics, paper, and textile waste. This material has good calorific value and can be used to generate power in waste-to-energy projects.

Although the cost of power generation through waste-to-energy projects tends to be slightly on the higher side, the objective is to scientifically manage waste and mitigate environmental impacts, particularly those arising from landfill fires.

Can waste processing be decentralised?

Given the challenges with identifying large land parcels, Delhi will need to partner with its neighbouring States to set up a few of these composting plants. Additionally, the market for organic compost produced from wet waste lies in the neighbouring States of Haryana and Uttar Pradesh.

Delhi city has 272 wards. States like Tamil Nadu and Kerala have set up decentralised Micro-Composting Centres (MCC) of five TPD capacity at the ward level. These MCCs can manage about 20% of the city’s wet waste. Bengaluru has also set up ward-level Dry Waste Collection Centres (DWCC) of 2 TPD capacity each. These DWCCs can help manage about 10% of the dry waste.

Delhi’s SWM system should integrate decentralised options for both wet and dry waste, backed by large processing facilities to ensure all the waste generated is scientifically processed. The city must also ensure existing processing facilities operate at full capacity, while new facilities are built to ensure no waste goes untreated. Finally, urban local bodies should also learn from best practices from other cities in India and abroad on efficient SWM processing.

Pradeep Dadlani works with Sycom Projects and Consultants, Delhi, and is a senior SWM expert with over 30 years of experience in advising urban local bodies and development agencies on efficient municipal SWM. Pushkara S.V. works with the Indian Institute for Human Settlements, Bengaluru, and is a practitioner in SWM with about 15 years of experience in setting up and operating waste-processing facilities.