Environment Counts | Municipal Solid Waste â€“ Garbage on a global scale
Author: Rick Higgins – Published At: 2012-08-22 16:36 – (1713 Reads)
The most recent global estimate of municipal solid waste (MSW, or just garbage) indicates approximately 1.3 billion tonnes is generated and collected annually in the worldâ€™s cities. This estimate does not include solid waste generated in rural areas or in myriad small towns and villages. This estimate along with breakdowns of the global data by major regions, countries and cities is provided in a recent World Bank report along with data on the composition of MSW and various correlations with per capita GDP. This article also references three other reports on MSW referenced by the World Bank; by the OECD, Eurostat and the USA EPA. â€œWorld Bank report. What a waste: A global review of solid waste managementâ€
The magnitude of MSWÂ globally
It appears to have been difficult (even for the responsible international institutions) to come up with a global estimate of total MSW (or garbage). Four reports published since 2009, however, shed light on the magnitude of the MSW problem at the global scale.
- In March, 2012 the World Bank brought the various international survey results and reports together and with their own surveys and research reported that estimated annual global MSW generated was in the order of 1.3 billion tonnes (one billion and three hundred million tonnes).
- In 2009 the OECD (Organization for Economic Cooperation and Development) reported total MSW from all of its member countries was in the order of 650 million tonnes.
- In 2009 Eurostat (the statistics agency of the European Commission) also reported that Europe generated more than 250 million tonnes of MSW annually.
- In 2011 the USA EPA (United States Environmental Protection Agency) reported the USA generated more than 240 million tons of MSW annually. (The USA is also included in the OECD totals.)
Together, these reports (along with national reports from smaller nations) are starting to provide the first consistent estimates of the global magnitude of the MSW problem, along with data on the composition, recycling and treatment methods being used at regional, country and city levels.
Other national statistics reported in the OECD and World Bank reports of interest include the following data for 2009; China (157,000 tonnes),Russian Federation (63,000 tonnes), Brazil (51,000 tonnes). India is reported at 18,000 tonnes and Indonesia at 10,000 tonnes, but the data for each of these countries may well be more illustrative of problems in MSW data reporting and/or definitions than of the actual national totals.
(Note: The above estimates do not include solid waste generated in rural areas or in myriad small towns and villages, particularly in developing countries.)
MSW generation by globalÂ region
Composition ofÂ MSW
Six waste types or categories are generally used in surveys to classify the composition of MSW. These type/categories and the typical source of waste in each is summarised in the following table from the World Bank report. The definition of what is and what is not included in each of these categories varies slightly across jurisdictions, and reports. The differences are relatively minor however and the following table (from pp 16 and 17 of the World Bank) is a useful summary of the types, sources and % composition of MSW at the global level.
Variations in the composition ofÂ MSW
Based on its research the World Bank concludes that waste composition is influenced by factors such as:
- economic development
- climate, and
- energy sources
In turn the composition of MSW at the city level impacts how often waste is collected and the most appropriate (or often the most affordable) method of disposal. The following generalizations regarding the composition of urban waste are made in the World Bank report. The report includes detailed tables at all levels on this issue, and some interesting correlations among these and per capita income levels.
- 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 (East Asia and Pacific) has the highest proportion of organic waste at 62%, while OECD countries have the least at 27%, although total amount of organic waste is still highest in OECD countries.
- Although waste composition is usually provided by weight, as a countryâ€™s affluence increases, waste volumes tend to be more important, especially with regard to collection: organics and inerts generally decrease in relative terms, while increasing paper and plastic increases overall waste volumes.
Disposal ofÂ MSW
Waste disposal methods are generally classed under the following activities, which are used by the World Bank and most other international organizations concerned with MSW.
- Waste-to-energy conversion
The following chart summarises these activities as a waste disposal and diversion hierarchy with the least preferred disposal action (dumping) at the base and moving progressively to more environmentally, health and sustainable activities as one goes up the pyramid .
The use and combination of each of these disposal activities varies significantly depending city and country factors. These factors include climate, per capita GDP and local income levels, geomorphology and cost. The various factors accounting for these variations are explained and addressed in the World Bank and the other reports.
A summary at the global level of MSW disposal activity is included in the following chart from p22 of the World Bank report.
Per capita GDP, income levels andÂ MSW
Waste collection, disposal and treatment is a critical aspect in maintaining public health in all cities. The amount of MSW collected varies widely by global region, per capita GDP and income level. The variations can also vary significantly (even widely) within countries and even within cities.
Collection rates range from a low of 41% in low-income countries to a high of 98% in high-income countries.
Although reliable quantitative data is not available for all countries, the following points are made by the World Bank. (Ch 6, p22 of the Report)
- Landfilling and thermal treatment of waste are the most common methods of MSW disposal in high-income countries.
- Most low-income and lower middle-income countries dispose of high proportions of their waste in open dumps.
- Several middle-income countries have poorly operated landfills which should be classified as controlled dumping.
The impact of per capita GDP income levels on the generation, disposal and treatment of MSW is currently a significant field of study and both the World Bank and OECD reports give attention to these relationships.
The types of waste composition generated vary considerably worldwide by income level, as seen in the following table from p19 of the World Bank report.
Urban waste generated by high per capita income regions is 3.5 times greater per capita than the lower income regions. High income regions generate some 2.13 kg/person/day, whereas lower income regions generate only 0.6 kg/person/day. The following table summarising this from p11 of the World Bank report.
MSW toÂ 2025
In the Executive Summary of its report the World Bank looks ahead and makes the following forecast.
“As the world hurtles toward its urban future, the amount of municipal solid waste (MSW), one of the most important by-products of an urban lifestyle, is growing even faster than the rate of urbanization. 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 tonnes per year). This report estimates that today these amounts have increased to about 3 billion residents generating 1.2 kg per person per day (1.3 billion tonnes per year). By 2025 this will likely increase to 4.3 billion urban residents generating about 1.42 kg/capita/day of municipal solid waste (2.2 billion tonnes per year).”
Source: Executive Summary, World Bank report.
Reliability of MSWÂ data
Waste disposal data are the most difficult to collect. Many countries do not collect waste disposal data at the national level, making comparisons across income levels and regions difficult. Furthermore, in cases where data is available, the methodology of how disposal is calculated and the definitions used for each of the categories is often either not known or not consistent.
This review is essentially a snapshot of broad and complex field. MSW may be viewed as a part of the overall subject of Waste. It is clearly a major environmental problem as well as a health issue for all cities in all countries.
This is the first article in the EC site focused on MSW. Future articles are planned dealing with the various environmental impacts of MSW, including leachates, greenhouse gas generation from MSW and the incidence of hazardous chemicals and metals in MSW. The purpose of this article is to scope out the magnitude of problem globally in terms of the amount of urban waste generated and the main types of disposal and treatment.
Sources andÂ links
The following sources have been used. The World Bank report is the main source quoted, but each of the other sources were reviewed and each provides useful and interesting data and information.
The three international organization reports each provides extensive tables summarizing data at both the national and major city levels. The USA EPA report is included as it provides a detailed case study of MSW in the worldâ€™s largest economy. Other national case studies are included within the other reference sections for the report listed below.
An interesting graphical presentation of various aspects of MSW is presented in Vital Waste Graphics 3 – UNEP and Basel Convention
Science Magazine has recently published an interesting edition on waste. The summary article is linked here, but the main articles are only available by subscription. Science Magazine – Waste summary