New Yorkers now have more ways to compost than ever before, and the city is slowly but steadily expanding just how much organic waste it can recycle. 

You can contribute to the pile at a local community garden, take it to a farmer’s market and drop it off at a special bin on the street corner. 

And if you live in Queens, you can once again wheel it to the curb.

On Monday, the city resumed curbside collection in Queens after a winter hiatus, the first borough where each building can put out food waste for pickup by city sanitation trucks. By 2024, Mayor Eric Adams has pledged, every city address will be able to put kitchen scraps out on the sidewalk next to trash and other recycling.

“We are on the cusp of something new here, something that the city hasn't seen,” said Ian Twine, the deputy director of compost at the sanitation department, in an interview at the Staten Island composting facility. 

Here’s your guide to the city’s process for recycling organic material, from carrot peels and chicken bones to Christmas trees and yard waste.
 

The piles of compost at the Staten Island facility give off scents of dry Christmas trees, bitter coffee and dark chocolate. (NY1/Ari Ephraim Feldman)

 

Where and how to recycle what

There are slightly different rules about what kind of organic waste you can recycle, depending on how you do it. 

Ultimately, the city recycles just a fraction of the 4,000 tons of organic waste it produces every day, according to the Department of Environmental Protection. Between January 2017 and the beginning of the pandemic, sanitation workers collected about 2,500 tons each month, on average, according to city data. 

Community gardens and compost pickups at GrowNYC greenmarkets generally discourage any animal products, pet waste, dead plant matter or plastics labeled as biodegradable or compostable. (Those products don’t degrade as quickly in the relatively low-temperature, open-air piles where this compost is heaped.)

If you have a curbside bin, you can put out just about any degradable item that comes through your kitchen, including bones, dairy products and food-soiled paper.

The same rules apply to the hundreds of SmartBins that the sanitation department has been installing across the city. (Download the department’s app to open the bins.
 

Ian Twine, the sanitation department's head of composting, stands in front of a mound of compost. (NY1/Ari Ephraim Feldman)

Destination Staten Island

From the drop-off or pick-up point, the organic waste goes to a different location depending on the borough and the hauler. 

The sanitation department’s compost facility on Staten Island, located on the former site of the borough’s famed landfill-turned-park system, receives waste from a few different sources: Contractors and builders bring yard waste and tree remnants;, the island’s public schools;, and nonprofit compost collectors like Grow NYC and Big Reuse. The facility is also the destination for many of the Christmas trees left out in January. 

The yard, tucked behind a highway on the island’s western side, is home to long, tidy mounds of decaying matter and a couple of building-sized piles of finished compost. In colder weather, steam seeps off the small hills, as the microbial community digesting the organic waste heats it up and belches out carbon dioxide and ammonia. 

Bulldozers patiently move the heaps here and there, aerating them and picking up the pace of the decomposition. 

“You get lost in the machinery, and watching something that was whole become compost, become small and minute,” Twine said. “It sort of puts everything in perspective, in terms of how we are on the planet in general.”

The facility makes sure to sort all its waste (about 20% of the compost waste stream gets contaminated with non-compostable items, according to DEP), which has yielded some surprising finds: The sensitive sorting machine, called a Tiger, has removed a trumpet, as well as textbooks, from school waste.
 

The DEP's locally famous digester eggs process hundreds of tons of sewage each day. (NY1/Ari Ephraim Feldman)

 

The stomachs of Greenpoint

Over in Brooklyn, a large proportion of the city’s organic waste goes to an entirely different kind of processing. Instead of the monthslong, open-air process found on Staten Island, the massive, egg-shaped digester structures at Greenpoint’s Newtown Creek Wastewater Treatment Plant break down waste in the absence of oxygen. 

“It works just like a human stomach,” said Jane Atkinson Gajwani, the DEP’s chief decarbonization officer, while speaking in front of the eggs.

Food waste here comes from curbside collection and SmartBins. The sanitation department picks it up and drops it off with the private garbage collector Waste Management, which creates a liquid slurry out of the food waste with fats from grease traps, expired milk and old energy drinks. 

Tanker trunks bring that slurry to Newtown Creek, where it is held in a 180,000-gallon underground tank and fed into the digester eggs. 

The eggs are primarily responsible for digesting sewage; compost makes up about a tenth of their supply of sludge. Boilers underneath the eggs heat the sludge up. Without oxygen to help break down the organic matter, the pools of waste instead give off methane gas, which is captured by the plant. 

Methane is a heat-trapping greenhouse gas when released into the atmosphere. Currently at Newtown, half the gas produced by the eggs is used on site, to keep the lights on and heat the boilers under the eggs. The other half is flared off into carbon dioxide, though DEP is planning to send that gas back to the city’s grid “soon,” according to the agency’s commissioner, Rohit Aggarwala.

Aggarwala said he thinks that using this kind of natural gas will be key to the city’s green energy transition in the coming decades, as some neighborhoods and buildings will be harder to fully electrify than others.

“We’re gonna need some sort of, we think, renewable natural gas. Not forever, perhaps. But for a while,” he said. “I’d rather have it be renewable gas that comes from sewage, and our food waste, than from fracking.”

While most of the waste in the eggs gets chemically digested into methane, some solids remain — and can be sent to special facilities outside the city to be composted into actual soil. Eventually, Aggarwala said, he hopes that city waste centers will be able to take in sewage and food waste and turn out soil you can use on your living room monstera, all on site.
 

DEP Chief Decarbonization Officer Jane Atkinson Gajwani and the city's Chief Climate Officer and DEP commissioner Rohit Aggarwala explained how the digester eggs worked to reporters earlier this month. (NY1/Ari Ephraim Feldman)

 

The future of composting

When the compost is ready to be put in pots and garden beds, it is primarily purchased by contractors for use in landscaping and planting. Some collectors, like GrowNYC, also sell compost from piles they manage. 

New Yorkers will also now be able to receive a limited amount of compost for free from the sanitation department at scheduled giveaways this spring and summer in Queens and Staten Island — you can sign up for a pickup slot at this website. (Nonprofits can also sign up for pickup or free delivery of compost in bulk.)

Each part of the city’s compost system is adding new capacity in anticipation of growing awareness of and participation in compost programs among city residents. 

On Staten Island, Twine is preparing to test a new concrete holding area for compost that continuously pumps air into the piles and keeps them covered with a special tarp. Those measures would halve the six- to eight-month timeline currently required to create soil-worthy compost — as well as increase the amount of wet tons of food waste they can take by twentyfold, from 30 tons a week to more than 600 tons.

The digester eggs, which take in 150 tons of material each day, have room altogether for another 100 tons daily. A similar facility in Hunts Point in the Bronx will also soon have capacity for 250 tons of waste per day. Aggarwala envisions the two plants as centerpieces of a hoped-for independent waste cycle that creates soil and gas from waste all inside the five boroughs.

“Composting is great. It’s space intensive,” Aggarwala said. “Given the choice between exporting organic waste for composting to outside the city versus processing it here within the city, it is, I think, a better choice to do it in the city.”

This summer, Twine said, the city will start working out where in the boroughs organic waste will go, part of the administration’s ongoing effort to create a citywide organics recycling master plan. 

After decades in the recycling industry, he said he is thrilled to see New Yorkers leaning more and more into composting. His message is that treating our food waste as a renewable resource is one way we can keep the Earth a habitable place for humanity. 

“We’re not saving the planet,” Twine said. “We're saving ourselves.”