Curbside composting bins joined recycling bins in 2001, and composting and recycling became mandatory in 2009. Now, city residents and business actually compost more material than they recycle. The city has also regulated construction and demolition debris, diverting much of it from landfills through recycling and reuse. Wood goes to steam-driven power plants in North Carolina to be burned as fuel; metal goes to scrap yards, then to foundries; sheetrock is composted; crushed concrete and asphalt go into new roads and pathways.

The city has also banned single-use plastic bags and other hard-to-recycle items. It recycles items other cities don’t: film plastic, clamshell food containers, and lower-grade plastics such as yogurt cups. San Francisco found new markets for some items after China shut the door to them last year. Its cutting-edge sorting technology produces cleaner, purer bales of recyclables, which are easier to sell.

Yet despite its green ethos, San Francisco has found reducing waste toward zero harder than expected. The amount of trash it sends to landfills declined by about half from 2000 to 2012, from 729,000 tons a year to 367,000. But then the gains stopped, and the amount of trash sent to landfills has crept up since, to 427,000 tons last year. The reasons include San Francisco’s spiking population, its residents’ increasing wealth and consumption, and the hyper-convenient plastics and other packaging that are more common in American life than they were a decade ago.

So last year, the city’s new mayor, London Breed, reset the city’s ambitions. Instead of zero waste by 2020, she said the city will, by 2030, cut all waste it produces by 15 percent and reduce the waste it sends to landfills by 50 percent.

Cutting trash in half again will be harder than the first time, a decade ago. “When you’re as far down the path as we are, it gets harder and harder to figure out how to get a good bump,” says Robert Haley, the zero-waste manager for the San Francisco Department of the Environment. “We have to change the way some products are made, and we’ve got to get people not consuming so much. And those are big challenges.”



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Looking back, San Francisco’s ambitious goal might have been too ambitious.

A California law, passed in 1989 to deal with a growing stream of waste and shrinking landfill capacity, was pressing cities to achieve a 50 percent waste diversion rate. In 2002, the city’s Board of Supervisors, urged on by an environmental commission, decided it could do better: 100 percent diversion, or zero waste, by 2020.

It was “a little forward-thinking and a little bit of hubris,” says Tom Ammiano, then president of the board, who’s now retired. “We wanted to take the lead.”

Today, Recology’s transfer station on the city’s southeast edge shows how far San Francisco falls short of that zero-waste dream—as well as how it’s made progress other U.S. cities might envy.