Recycling Food Scraps

Everyone knows we should recycle plastic, glass, aluminum and paper--or at least, we know we're supposed to. But for leftover Chinese takeout and other kitchen scraps, which make up around 30% of our residential garbage stream, there are usually only two options: do the messy work of making compost for the backyard garden--or toss the glop down the disposal or into the trash.

But San Franciscans like Ellisa Feinstein have another option for their organic waste: put it out on the curb with the glass, plastic and paper, where it will be picked up and recycled by the city. For the past several years, San Francisco has offered curbside recycling of food scraps, shipping leftovers to industrial-scale composting facilities, which process 300 tons of organic waste a day. For Feinstein, the curbside program allows her to salve her green conscience without the ickiness that came from composting her own used tea bags. "It's great because it helps me do my job of diverting garbage from the landfill," she says. "And it's really easy."

Deep-green San Francisco isn't the only city to offer curbside food-scrap recycling. Across the bay, Alameda County--which includes Berkeley--also recycles organic waste from residences and restaurants, and in Seattle, the massive Cedar Grove recycling facility handles 40,000 tons of food waste a year. Toronto has the most extensive organic recycling program in North America, and Portland, Ore., is considering adding curbside food-scrap pickup.

It's still a rare service in the rest of the U.S.--less than 3% of the more than 30 million tons of organic waste we produce annually is recycled. "This represents a great opportunity in the world of waste," says Kate Krebs, executive director of the National Recycling Coalition. "We just think about this stuff as garbage, but there's so much we can do with it."

Food scraps are a recent focus for recyclers in part because, unlike glass and plastic, organic waste will decompose once it's put in the ground. But that becomes a problem in municipal landfills. As buried food breaks down in these oxygen-free environments, it produces methane, a greenhouse gas that has a warming effect 23 times as potent as carbon dioxide. Global methane emissions from garbage are estimated to be as high as 70 million metric tons a year. By recycling organic waste--composting it--methane emissions are eliminated.

Financially, organic recycling is a no-brainer. It's cheaper in many areas to recycle food waste than to consign it to valuable landfill space, and the compost can be sold as organic fertilizer. (San Francisco brews a variety of compost recipes from its waste and sells them to more than 200 local vineyards.) But first you need to get citizens on board. In San Francisco, about half its residents participate in the curbside program, along with thousands of restaurants. The key is getting over what Robert Reed of Norcal Waste Systems calls the "ick factor"--the fear that leaving food in a curbside bin will lead to bad smells and marauding rodents. But that problem can be solved with biodegradable bags, and ultimately putting food scraps out for recycling shouldn't be any different from leaving it out for the garbage truck.

THE PROCESS

A New Life for Leftovers

Food waste makes up about 30% of the average home's garbage, but unlike glass and plastic, most of it ends up in landfills. Here's how San Francisco and other cities are turning these scraps into fertilizer and reducing greenhouse-gas emissions along the way

1 PICKUP Some West Coast cities allow residents to put food waste in recycling bins for curbside pickup

2 PREPARATION Magnets and grinders remove metal and other inorganic waste mixed in with the food scraps

3 COMPOST The material is compressed, and bacteria help speed decomposition

4 MATURATION Gore-Tex covers help limit odors as the compost goes through the aeration process

5 DELIVERY The finished compost is sent to nearby farms to be used as an alternative to chemical fertilizer