Organic material — yard and food waste — accounts for as much as 35 percent of Boston’s residential trash. Because most food waste is 90 percent water, it’s not great fuel for waste-to-energy plants that take the vast majority of Boston’s residential waste. Organic waste that goes to a landfill releases methane, a potent greenhouse gas. 

The city makes yard waste disposal fairly simple with regular curbside pickup. In an average year, yard waste pickup takes roughly 10,000 tons out of the waste stream. Picked up bimonthly throughout spring, summer, and fall, the yard waste goes to a collection facility on American Legion Highway, where it is gathered into 10-foot high piles to break down. 

But according to Brian Coughlin, superintendent of waste reduction with the Boston Department of Public Works, the term “yard waste” should not be interpreted as “whatever I find in my yard.” 

“We find lawn chairs, cinder blocks, wooden picket fences, you name it,” said Coughlin. “Leaves, grass, and small branches are what’s meant to be collected.” 

Once the yard waste has broken down, it gets screened and sent to community gardens and parks. Residents can drop yard waste at 500 American Legion Highway most Sundays; for those seeking to take advantage of yard waste pickup, the City of Boston Trash app sends push alerts to remind residents of yard waste collection days. 

But food waste is a bit more complicated. 

Boston does not currently offer a city-wide curbside composting program. As an alternative, the city launched the pilot program “Project Oscar” — named for the “Sesame Street” character — where communities have centralized drop-off locations for food scraps. Anyone in the area can take an online test, verify that they understand the basics of composting, and get a code that accesses the food waste bins.

Today the bins are in five locations, none of which are in Dorchester. A previous drop-off site in Grove Hall was shut down due to numerous contamination issues and general underuse. City officials are currently soliciting opinions for Project Oscar bin locations on its website.

Black Earth Compost in Manchester, Mass. currently picks up the “Project Oscar” totes. The company also provides weekly curbside pickup services and has just under 100 customers in Dorchester today.

Many cities of a comparable size to Boston offer municipal curbside pickup, including San Francisco, Edmonton, and Milan. In San Francisco, participation is compulsory. Freddie Coronado, residential zero waste assistant coordinator in that city, said the municipality was motivated to require composting because landfilling organics stopped making economic sense. 

“Realistically, making it mandatory is how you’re going to get high recovery rates from the landfill. If it’s just an opt-in program, diversion won’t be as high,” said Coronado. “We wanted to create something that was going to make a lasting impact.”

To overcome challenges such as an old building stock without space for additional binge storage, as well as narrow streets and sidewalks, the team in San Francisco started with the space issues. Instead of using a standard 96-gallon tote, San Franciscans are given a 64-gallon bin for recycling, a 32-gallon bin for compost, and just a 16-gallon bin for trash.

“Bin size matters,” said Coronado. “It’s a visual reinforcement that only a small amount can go into the trash, so you have to find other places for them.”

To address the needs of a diverse population, including low-income residents who may not be able to prioritize climate change until their basic needs are met, the city provides more resources to affordable housing units, and works with residents who have contamination notices before they turn into charges.

“We do a lot of outreach and training for these properties, because a contamination charge could be a big financial change for them,” said Coronado.

San Francisco emphasizes education in what items go into which bin through color coding. Decals on each bin indicate what is safe to toss. The city also provides a kitchen pail and compostable, corn starch-based bags for gathering the scraps to all residents.

Notably, the program isn’t actually executed by San Francisco. The city’s trash hauler runs the program and profits from it by selling the finished compost to the many area wineries, where it is in high demand. The city acts as more of a program overseer.

Could a similar setup work in Boston? Coughlin says a city-run curbside composting program would cost tens of millions of dollars to launch and run.

Currently, after the “Project Oscar” curbside pickups, the Black Earth team mixes the food waste with leaves, woodchips, manure, wood shavings, horse bedding, and other carbon. The waste is then pushed through grinder buckets, put it in a wind row, turned six times and nine months later, it is screened and bagged for sale in garden centers as well as bulk shipments. 

Black Earth Founder Conor Miller said he was stunned when he moved to Boston from the Seattle area.  “I couldn’t believe there was no composting out here,” Miller said. “There’s money, education, progressive values... how the hell is there no composting?” 

Ten years ago, the World Economic Forum forecast that the planet had 60 years of topsoil left. Soil degradation has made it a finite resource.

“Soil is a bank,” said Miller. “We’re withdrawing and not depositing. Food today has half the nutrients it had 50 years ago. Which means we’re getting half the nutrients in our bodies.”

The more people who sign up for curbside composting with Black Earth in an area, the cheaper the price per person. In some towns in Massachusetts, such as Beverly, the cost is $39.99 for six months. The town then adds a $10 subsidy, making curbside composting $1/week for Beverly residents.

“We want it to be so cheap that anyone who wants to do it can afford curbside composting,” said Miller.