In San Francisco last week, mandatory food waste recycling went into effect.

Residents and businesses now put food waste into a separate bin for trash pickup, and it all gets hauled to the Organics Annex, the city’s composting facility. The goal is to get food matter out of the waste stream, and out of the landfill.

And it’s not just about saving space in the landfills. When compostables, including paper, food and yard waste, are buried, they break down without oxygen and release methane, a major greenhouse gas.

“No matter how the waste industry ‘greenwashes’ its ‘new and improved landfills,’ there is only one proven method to truly prevent methane emissions — keep compostable organics out of landfills,” according to the San Francisco Department of the Environment. “Public policy needs to first support the elimination of methane by requiring source separation of compostables and recyclables . . .”

San Francisco already has an aggressive recycling program, and the food waste policy is the latest venture. The city’s goal is to eliminate a minimum of 75 percent of food and paper waste from landfills by 2012.

In Albany, the environmental group Save the Pine Bush has suggested a citywide food composting program. Last week, the organization sued the city of Albany and the state Department of Environmental Conservation over a planned expansion of the Rapp Road landfill, on the grounds that it will further encroach on the environmentally sensitive lands of the Pine Bush.

The lawsuit notes that the city of Albany has failed to come up with a solid waste disposal plan other than expanding the landfill, despite studying the problem since 1992.

Eliminating waste at the source — that means us — is the easiest way to prevent landfills from expanding.

Almost a quarter of all household garbage in the U.S. is made up of yard and food waste, according to the federal Environmental Protection Agency. By composting these — that is, collecting, piling and stirring so they can break down, in the presence of oxygen — you keep them out of landfills and create a nutrient-rich garden and landscape enhancer. Composting captures carbon, rather than releasing it as a noxious gas into the atmosphere.

I guess we all know that Americans contribute far more waste per capita than most of our compatriots, even in other developed countries. A friend who spent a semester in France found her landlord kept returning to her things she had thrown out that the landlord considered reusable — empty jars, wearable clothing, half-used tubes of lotion, for example. She thought my friend was wasteful.

We all are. And especially with food. Dumpsters behind grocery stores and restaurants are filled with food — much of it still edible. That food waste could easily be eliminated. Businesses could do a better job with inventory management to avoid overstocking. Raw foods that are still edible could be donated to food pantries or soup kitchens, or used to feed livestock. And waste foods — cooked or prepared foods or raw foods too far gone — could be composted. Along with environmental benefits, it would save all those businesses money in waste hauling.

I know a lot of what gets tossed is good food. One night last week, my neighbor called asking if he could drop off a few boxes of “goodies” for us and the chickens. He was talking about what was left from boxes of vegetables that a grocery store had donated to his church’s food pantry, and the food pantry had already picked through for donations.

“It’s a lot of greens,” he said. “I already handed some out at the bus garage, and we took what we wanted.”

It was late, but the ball game had gone to extra innings again, so we were still up when he showed up with three boxes. And so we picked through them. There were a lot of greens, some older bananas good for baking, some perfectly good oranges and a cantaloupe. Much of the rest went to the chickens, oxen and pig. And whatever was left, including peels and rotted herbs, went to the compost pile.

It’s hard to compost when you live in a city. Which is why policies like San Francisco’s make so much sense. Homeowners separate trash into three bins: blue for recycling, green for composting and black for the rest of the garbage.

It seems like an easy program to try all over the country.

Margaret Hartley is the Gazette’s Sunday and features editor. Greenpoint appears in the Gazette’s print edition Sundays on the Environment page.

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