The World Bank study What a Waste: A Global Review of Solid Waste Management, under its Urban Development Series, projects that solid waste management cost will go up from $205.4 billion in 2010 to about $375.5 billion by 2025. The handling of solid waste is expected to be a major issue in urbanisation with urban residents likely to go up by 1,304 billion (43 per cent) by that year.

As the world speeds toward its urban future, the amount of municipal solid waste, one of the most important byproducts of urban lifestyle, is growing even faster than the rate of urbanisation. Ten years ago, there were 2.9 billion urban residents who generated about 0.64 kg of MSW per person per day (0.68 billion tpa); current estimates place waste generation at 1.2 kg per person per day (1.3 billion tonnes per year) by three billion urbanites.

By 2025, there would be 4.3 billion urban residents generating about 1.42 kg per capita per day of municipal solid waste (2.2 billion tpa). As countries, particularly India and China, continue their rapid pace of urbanisation and development, global solid waste quantities are projected to increase considerably.

While service levels, environmental impacts and costs vary dramatically, solid waste management is the most important municipal service. Currently, world cities generate about 1.3 billion tonnes of solid waste per year. This volume is expected to increase to 2.2 billion tonnes by 2025. Globally, solid waste management cost will increase by 82 per cent to about $375.5 billion in 2025. Cost increase will be most severe in low income countries (more than 5- fold increases) and lower-middle income countries (more than fourfold increase). There is a strong correlation between urban solid waste generation rates and GHG emissions.

MSW collection is an important aspect in maintaining public health in cities around the world. The amount of MSW collected varies widely by region and income level; collection within cities can also differ greatly. Collection rates range from a low of 41 per cent in low-income countries to a high of 98 per cent in high income countries. Waste composition is influenced by factors such as culture, economic development, climate, and energy sources. Low-income countries have the highest proportion of organic waste. Paper, plastics, and other inorganic materials make up the highest proportion of MSW in high income countries. By region, EAP has the highest proportion of organic waste at 62 per cent, while OECD countries have the least at 27 per cent, although total amount of organic waste is still highest in OECD countries.

Land filling and thermal treatment of waste are the most common methods of MSW disposal in high-income countries. Although quantitative data is not available, most low- and lower middle income countries dispose off their waste in open dumps. Several middle-income countries have poorly operated landfills.

The waste recycling industry, with more than two million informal waste pickers, is now a global business with international markets and extensive supply and transportation networks. Locally, uncollected solid waste contributes to flooding, air pollution, and public health impacts such as respiratory ailments, diarrhea and dengue fever. In lower income countries solid waste management is usually a city's single largest budgetary item.

ESTIMATED SOLID WASTE MANAGEMENT COST ($ BILLION)
Country Income Group	2010	2025
Low Income Countries7	1.5	7.7
Lower Middle Income Countries8	20.1	84.1
Upper Middle Income Countries9	24.5	63.5
High Income Countries10	159.3	220.2
Total Global Cost ($)	205.4	375.5
Note: Cost of SWM = waste generated (tonnes) x per cent of waste collected x (cost of collection ($/tonne) + cost of disposal)