Though the average citizen notices little of the waste he or she generates, the sum total of each person’s garbage has resulted in the generation of astounding quantities of solid waste. Throughout the last few centuries of modernization and industrialization, the disposal of waste has mounted into an increasing problem (1).
Cities, especially those in developing nations, compound the problem of waste. By 2030, two-thirds of the world’s population will live in cities. Each month, more than 5 million people migrate to urban areas in search of fresh opportunities (2).
In 1900, the world had 220 million urban residents, which was 13% of the population at that time. Then, the world generated fewer than 300,000 metric tons of garbage per day (1). In 2000, however, 2.9 billion humans lived in cities and the world generated 3 million tons per day. By 2020, the quantity of waste generated by day is estimated to double again.
Already, cities account for two-thirds of the world’s energy consumption and 70% of the global greenhouse gas emissions. Nearly a billion of the urban poor live in slums of cities. At the same time, cities generate nearly 80% of Gross Domestic Product (GDP).
Urban communities tend to use more packaged products, generate more food waste, and engage in more manufacturing than their socioeconomically equivalent rural communities. For example, the same level of wealth in an urbanite generates twice as much waste produced per day as the urbanite’s rural counterpart (1).
Country and culture also influence the quantity of waste generated. Despite similar GDP per capita, the average Japanese citizen creates only two-thirds of the trash of the average United States citizen (1). This may be attributed to Japan’s higher density of living, higher prices for a larger share of imports, and differing cultural norms (1).
Additionally, China exhibits trends of enormous solid waste production and holds the title for the fastest-growing area of the world for waste. The country produced 525,550 tons per day in 2005 and is projected to produce 1.4 million tons per day in 2025. However, China may soon be surpassed by India in 2025 and then sub-Saharan Africa around 2050 (1).
Cities do tend to reach a certain limit of waste generation after its denizens become increasingly wealthy and its living standards increase. But the timing of peak solid waste generation is difficult to determine. In a recent study published Nature, the current levels of population growth and material wealth are predicted to peak after the end of the 21st century (1).
Modernized countries such as the United States will peak in their waste production by 2050. Asia-Pacific countries will follow in 2075, but waste production rates will continue fast in sub-Saharan Africa. By 2100, the world will produce 11 million tons of waste per day – three times today’s rate. Even then, the world is still predicted to produce increasing amounts of waste (1).
However, measures may be taken to prevent such an eventuality – waste production may reach its climax as early as 2075 with such innovations. Lower populations, denser and more resource-efficient cities, and less consumption alongside with higher affluence may hasten the decrease in waste production (1).
Rapidly urbanizing cities require the greatest attention. Increased education, equality, and targeted economic development could stabilize the population to below 8 billion by 2075 (1). Another component lies in the study of urban metabolism and ecology, which is examination of systems through which materials and energy flow through the city (1).
The impacts of today’s waste already take enormous tolls on the planet environmentally, save the economic and social impacts. With the right factors – stable and declining populations, denser and better-managed cities that consume fewer resources, and greater equity and use of technology – the peak of waste production will occur sooner and incur fewer lasting consequences (1, 2).
1. Hoornweg, D., Bhada-Tata P., Kennedy C., “Environment: Waste production must peak this century” (30 October 2013). Available at http://www.nature.com/news/environment-waste-production-must-peak-this-century-1.14032
2. Hoornweg, D. & Bhada-Tata, P. What a Waste: A Global Review of Solid Waste Management (World Bank, 2012). Available at http://web.worldbank.org/WBSITE/EXTERNAL/TOPICS/EXTURBANDEVELOPMENT/0,,contentMDK:23172887~pagePK:210058~piPK:210062~theSitePK:337178,00.html