Intercepting landfill-bound food scraps by composting them is something many have done for years, thinking it’s the right thing to do. Well, a new University of Washington study confirms that it is.
The study calculated the environmental benefits associated with keeping these organic materials out of landfills and found that food waste generates "significantly more" of the greenhouse gas methane when buried in landfills than when it’s composted.
"Putting your food waste in the compost bin can really help reduce methane emissions from landfills, so it's an easy thing to do that can have a big impact," said Sally Brown, a UW research associate professor of environmental and forest sciences.
Keep on composting
Brown’s study, set to appear in the January 2016 issue of Compost Science & Utilization analyzes new changes to a U.S. Environmental Protection Agency model that helps solid waste planners estimate greenhouse gas emission reductions based on whether materials are composted, recycled, burned, or thrown away.
With compost, the model calculates how much methane is produced over time in landfills as organic materials decay. It also considers how much methane from landfills is currently captured in collection systems versus being released into the atmosphere. The results are overwhelmingly in support of composting food waste rather than sending it to landfills.
In the U.S., about 95% of food scraps are still thrown away and eventually end up in landfills. The scenario is better for yard waste — grass clippings, leaves, and branches — with more than half diverted to compost facilities instead of landfills.
So how can you help?
More than one-third of all waste that enters landfills could be composted instead. So if you live in a place where compost is an option, use it — and pat yourself on the back for doing so. With landfills brimming, conserving space in existing landfills remains imperative to reducing potent greenhouse gas emissions.
Seattle and King County were among the first municipalities nationwide to adopt food waste composting and curbside pickup. Other leaders include San Francisco, New York City, and the states of Vermont and Massachusetts. There are now more than 90 cities that offer the service.
But even if you’re not a resident of these municipalities, you can help. Composting locally at the neighborhood or community-level yields many benefits: improved local soils, greener spaces, enhanced food security, fewer food deserts, less truck traffic hauling garbage, and increased composting know-how and skills that can be reinforced in the next generation. Local, small-scale composting helps community participation and education flourish.