We have a garbage problem. Not just here in the United States, where the average person throws away their body weight every month–but increasingly around the world as well. Growing prosperity and urbanization are leading to a big surge in the waste mountain. And, a new analysis suggests the problem is likely to keep growing this century, unless there’s serious change.

Global waste has bulged 10-fold in the last century. And by 2025, it’s set to double from where it is today, according to a study in the journal Nature. The chief reason: newly rich cities of the developing world. Dumps like Laogang in Shanghai and Jardim Gramacho in Rio de Janeiro are already overflowing. China’s solid waste is set to grow from about 573,000 tons a day in 2005 to 1.5 million tons in 2025.

Urban-dwellers produce four times as much waste as country folk.

“As a country becomes richer, the composition of its waste changes. With more money comes more packaging, imports, electronic waste, and broken toys and appliances,” says the article by Daniel Hoornweg, Perinaz Bhada-Tata and Chris Kennedy. In turn, that leads to environmental problems, like toxic leakages from landfills, and plastic clogging oceans and rivers.

The analysis is based on population projections and material consumption rates. East Asia is now the fastest growing waste region, with South Asia set to take over after 2025 and sub-Saharan Africa after 2050. Waste rates in richer countries, like the U.S., are also still rising. But the authors expect them to stop growing by mid-century.

“Although OECD countries will peak by 2050 and Asia–Pacific countries by 2075, waste will continue to rise in the fast-growing cities of sub-Saharan Africa. The urbanization trajectory of Africa will be the main determinant of the date and intensity of global peak waste,” the article says.

China’s solid waste is set to grow from about 573,000 tons a day in 2005 to 1.5 million tons in 2025.

Urbanization is key. People in cities generate twice as much waste as rural residents, even if they have the same income. Rural communities normally use less packaged products and throw away less food. When the authors account for income differences, urban-dwellers produce four times as much waste as country folk.

The authors say the world could produce more than 12 million tons of garbage per day by the end of the century, if we don’t shift from our current trajectory. They recommend the rest of the world take a cue from San Francisco’s book (it has a zero-waste policy), and introduce disposal fees that put a price on waste generation. “Increased education, equality, and targeted economic development” could cut population growth, limiting waste naturally, they add. Better material reuse could keep a lot of material out of landfills.