Making Dirt Out of Dinner

One gray morning last October, three students at Barnard College in New York City brought a bit of sunshine to their classmates with hot cocoa and a cheerful message about a stinky subject: composting. They had set up a table on a small lawn near the center of campus to demonstrate a new three-foot rotating composter, which apartment-dwelling students can now use to dispose of their kitchen scraps. These women were the vanguard of a sustainable trash campaign, and the composter was just the latest weapon in their arsenal.

In the past few years, composting programs like Barnard’s have sprouted up at many of New York City’s universities, due in large part to demand from environmentally conscious students. These schools also serve as a sort of test case for citywide composting. Though New York has no current plans to implement full-scale composting, such a program would have the potential to significantly reduce both trash in landfills and greenhouse gas emissions. At least seven U.S. cities, including San Francisco and Seattle, currently have curbside compost programs.

About half of household waste in New York City is organic matter, according to a 2004 assessment by the city’s sanitation department. Based on figures from the department’s 2008 annual report, New York City curbside trash puts over 100,000 tons of organic material into landfills in a typical month, nearly enough to fill Giants Stadium.

Composting that organic material would not only reduce landfill volume, it would also reduce greenhouse gas emissions. When organic matter decomposes in a landfill, the lack of available oxygen means the carbon in it becomes methane, or CH₄, instead of carbon dioxide, or CO₂. Per molecule, methane traps 21 times as much heat as carbon dioxide. Landfills were responsible for nearly a quarter of U.S. methane emissions in 2007, according to the EPA.

Composting may be important, but in Manhattan’s urban environment, it’s difficult to put into practice.

“Our challenge is space,” said Nilda Mesa, the assistant vice president in charge of Columbia University’s environmental sustainability program. “We also want it to be budget-neutral, and we don’t want to add to the vermin problem.”

Many universities are starting with their centralized dining facilities. There, scraps from food prepared in the kitchen, rather than those left on students’ plates, can be composted fairly easily.

Columbia is selecting a machine that would produce compost for use on campus grounds, said Mesa. Barnard already has a composting machine in its dining hall, which grinds kitchen scraps to be released into the sewer. New York University pays a collection service to truck its kitchens’ organic waste to two farms upstate that sell compost commercially.

Composting food after it’s on a student’s plate is a little more tricky.

“We made a conscious decision not to ask the users to sort,” said Sarah Boll, the recycling coordinator at NYU. Acadia Roher, a student sustainability advocate at Barnard, described students who flat-out refused to separate their leftover dinner from their non-compostable trash. Because of the sorting issues, all three universities have chosen not to collect organic waste after the students eat, at least for now.

New York’s sanitation department similarly decided not to ask residents to sort when it conducted a compost feasibility study a few years ago. During a pilot composting program in the 1990s, residents in test neighborhoods separated only a small fraction of their organic waste. In addition, the lack of space for a whole new set of trash bins makes curbside collection programs prohibitively difficult in New York City, according to the study’s 2004 report.

The city is, however, working to educate its residents and institutions about composting. Debbie Sheintoch, who manages the NYC Compost Project, said the city has helped provide many universities, including NYU, with the education and tools needed to start their compost programs. They’re also keeping an eye on the university programs to see how they do.

Like its universities, New York City is approaching the compost question by making inroads where it can with small-scale composting and education programs. Chipping away at that monthly Giants Stadium of organic waste is slow going, but New York City is making progress.