Cities cover 2 percent of the world's surface, but generate 70 percent of the world's waste. With increasing urban populations and consumption in developing nations, levels of urban waste can be expected to continue growing.
Researchers have come up with a new tool to improve the measurement of waste management performance, according to a recent study. In the study, "The zero waste index: a performance measurement tool for waste management systems in a 'zero waste city,'" researchers found that San Francisco is closer to achieving zero waste than Stockholm and Adelaide, due to its emphasis on reusing solid waste.
The researchers disagree with the commonly held belief that zero end disposal through landfill is the same thing as zero waste, and argue that this definition does not place enough emphasis on how waste can be reused as a material resource (as opposed to being incinerated, for instance). Moreover, the findings highlight potentially large differences in cities' approaches toward zero waste and the varying outcomes those approaches may have on sustainability issues, such as natural resource use and climate change.
Although the Zero Waste Index is a relatively simple tool for city waste managers to use, the study illustrates its potential to increase the sophistication of our understanding and monitoring of "city metabolisms" in pursuit of zero-waste cities.