Experts from Imperial, working independently through Imperial Consultants, have helped deliver a major new global analysis of rising waste, climate emissions and failures in basic rubbish collection.
The world is on track to generate 3.86 billion tonnes of municipal solid waste a year by 2050, up from 2.56 billion tonnes in 2022, according to What a Waste 3.0, a new report from the World Bank Group. Drawing on data from 217 countries and economies, and 262 cities, the report shows that waste generation is rising faster than many cities and countries can manage it, with growing consequences for public health, climate emissions and urban development.
The report presents clear evidence that a global solid waste management crisis persists. Local failures, especially in basic waste collection, have worldwide consequences. Dr Costas Velis Department of Civil and Environmental Engineering
"Waste is often treated as a local sanitation issue, but the evidence shows it is also a global climate, public health and development challenge," said Dr Ed Cook, a research associate in waste management in the Department of Civil and Environmental Engineering, and the report's lead author. "What this report shows very clearly is that waste generation is rising faster than municipal systems can cope with. At the same time, it also shows that better outcomes are possible if countries invest in collection, controlled management and more ambitious waste prevention and recovery."
Around 30% of the world's municipal waste is still dumped or left uncollected, the report finds. In low-income countries, only 28% of waste is collected and just 3% is managed in controlled facilities, compared with almost 100% in high-income countries.
"The report presents clear evidence that a global solid waste management crisis persists. Local failures, especially in basic waste collection, have worldwide consequences," said Dr Costas Velis, Associate Professor in Waste and Resource Engineering.
Members of Dr Velis's research group, working independently through Imperial Consultants, made a significant contribution to the report. In addition to being one of the lead authors, Dr Cook wrote chapters presenting a global picture of solid waste management and setting out scenarios for reaching circularity by 2050. He was supported by Dr Josh Cottom, a research associate in plastic pollution, who advised on scenario modelling, while Dr Velis contributed to major parts of the methodology and data analytics.
Waste is becoming a bigger climate problem
Among other findings, the report highlights the growing impact that poor waste management has on climate. In 2022, the waste sector generated an estimated 1.28 billion tonnes of CO2 equivalent, including 1.15 billion tonnes from methane. Under current practice, waste-sector emissions are projected to rise to 1.84 billion tonnes of CO2 equivalent by 2050.
Food waste is a major contributor. It makes up 38% of municipal waste globally, yet only 6% of waste is composted or treated through anaerobic digestion.
Meanwhile, the report estimates that 93 million tonnes of plastic waste are mismanaged each year worldwide. It also points to a basic but persistent problem: in many parts of the world, waste is still not being collected at all. That matters not just for cleanliness, but for health, pollution and living conditions in rapidly growing cities.
At the same time, waste management and recycling support an estimated 18 million urban waste workers worldwide, many of them working informally in lower-income countries.
The report also sets out a more ambitious alternative. Under a high-ambition scenario, global waste generation could be held close to current levels by 2050, while waste-sector emissions could fall to around 0.91 billion tonnes of CO2 equivalent.
"Optimistic scenarios show that reducing waste generation and improving management must advance together, particularly in regions with rapidly growing populations and economies," Dr Velis said. "Still, a clear bold priority for many countries in the Global South would remain basic collection and safe management, and getting that right delivers maximum benefit for health, climate and the environment."
What a Waste 3.0 is the third edition of the World Bank's flagship waste report series, following earlier editions in 2012 and 2018.
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