We all produce waste, but the way we manage it is the most important factor that affects the environment. Waste generation globally is high and growing day by day, and if left unmanaged the waste will create crises in many cities and countries, and their surrounding ecosystems, while simultaneously representing a lost economic opportunity.
One area that requires our immediate attention is solid waste management. Because of the unregulated dumping of waste, solid waste generated is a large contributor to Greenhouse gas emissions (GHG). Some estimates suggest that 2.6 billion tonnes of CO2-equivalents will come from waste in 2050, with methane from decomposing organic waste as the largest GHG contributor from the waste sector, and open dumpsites will be responsible for up to 5-10 percent of the global anthropogenic GHG by 2025 under a business as usual scenario. (UN-Habitat, 22 March 2021).
How Waste Management affects Climate Change
- Reduces GHG emissions
- Saves energy
- Increase forest carbon sequestration
- Reduces the size of landfills
- Reduces Methane emissions through decay
How Climate Change affects Waste Management
- Change in site hydrology and temperature implies risking changes to landfill degradation rates and leachate production
- High risks erosion of low-lying facilities in coastal areas
- Health risks, odours, and dusts
- High risk of subsidence in landfills from extreme weather changes
Globally, about 70% of the solid waste is landfilled, 9% is recovered through composting or recycling, and 11% is converted to energy through technologies. As per a recent World Bank report, emissions from landfills contribute to about 5% of total GHG emissions and 12% of the world’s emissions of methane. As highlighted in the Clean Development Mechanism (CDM) and Joint Implementation (JI) of the Kyoto protocol, there lies great potential for addressing methane emissions by reducing waste that ends up in a landfill.
Methane Emissions from Landfills
Methane is created and released into the atmosphere by biological processes during the anaerobic decomposition of wastes in landfills and open dumps. The landfill gas contributes approximately 50% methane, 50% carbon dioxide, and a small amount of non-methane organic compounds. Methane gas is 23 times more potent at trapping atmospheric heat than carbon dioxide and its emission levels from a source depend on factors like Climate, Quantity and Moisture content of the waste, industrial and agricultural production, Various energy usage, and Waste Management practices. Methane emissions from landfills can be captured and used as a significant energy resource.
Changes in LFG (Landfill Gas) Composition after Waste Placement
Bacteria decompose landfill waste in four phases. Gas composition changes with each phase and waste in a landfill may be undergoing several phases of decomposition at once. The total time and phase duration vary with landfill conditions.
Some Major Challenges
Some of the challenges concerning solid waste management include:
i. Infrastructure for segregation: Presently, mixed waste is collected and sent to landfills/ compost plants. However, proper waste segregation is required at the source of waste generation, collection, and transportation.
ii. Waste generation on the roadside: Street hawkers and vendors generate garbage throughout the day and leave them on the roadside. Lack of monitoring by the local authorities further adds to the problem.
iii. Lack of public awareness: There is also a lack of public awareness about sanitation and hygiene in the city. There is an urgent need for aggressive campaigns to encourage behavioral changes for people to keep the city clean.
How can we change this?
A lot can be improved if we, the humans, slightly change our behavior and approach towards the environment and start acting responsibly. We can avoid unnecessary waste by managing it in such a way that it avoids landfills. The two types of waste- Biodegradable and Non- Biodegradable, can be separated starting from home and then treated further.
The United Nations Environment Programme’s (UNEP) initiatives align with the prioritization of activities presented in the waste management hierarchy. As described by the International Solid Waste Association (ISWA 2009), “the waste hierarchy is a valuable conceptual and political prioritization tool which can assist in developing waste management strategies aimed at limiting resource consumption and protecting the environment”. In the hierarchy, the priority is given to waste minimization, re-use, recycling, waste-to-energy, and finally landfill. (Waste and Climate Change: Global trends and strategy framework, UNEP)
The waste hierarchy
As individuals we can help to reduce the production of waste by contributing a little possible in the following ways:
- Refuse: By refusing what you don’t need you reduce the generation of waste, along with the resources to be used for the production, transport, use and disposal of that item.
- Reduce: One can always try to reduce the use of those items that you do need. For example, purchasing products in bulk, rather than individually packaged items. This will eventually reduce the amount of waste generated and managed and thus reducing the GHG emissions.
- Reuse: By reusing what you can’t reduce prevents the return of the carbon within the materials to the environment for as long as possible, reducing the demand for new raw materials and minimizing climatic impacts.
- Recycling: Recycling what you can’t reuse is another effective strategy, which can be done at home for a few items as well as requires the waste to be transported to a processing centre.
- Recover: Recovering what you can’t recycle is also effective as recovering value from the waste offsets the GHG emissions, and converts waste into another usable form.
– Segregation of waste at source into biodegradable and non-biodegradable waste, domestic hazardous wastes
– Incentives like rewarding and recognizing the households by giving certificates, publishing their names on respective websites or reduction in property tax, etc.
– Local Authorities should strengthen systems for collection, transportation, and processing of the segregated waste
– Impose fees and penalties for every generator decided by the bye-laws of the local authority.
GHG emissions from waste can be effectively channelized by existing technologies, which will be cost-effective and profitable in many developed countries. However, in developing countries, lack of capital and technologies is a major barrier.
The benefits of the avoidance and diversion of waste that goes into landfills should be stressed and implemented on a global scale. This has proven feasible and affordable to significantly reduce the carbon footprint via proper waste management. So let’s start by contributing to the bigger cause.
First published in Center for Regional Research and Sustainability Studies titled Solid Waste Management: An Attempt to Go Green on 24 December 2021.
About the Contributor
Swati Solanki is Research Assistant and Assistant Editor at IMPRI. She is currently pursuing her Master’s degree in Economics from Delhi School of Economics, University of Delhi.