By Donald Gilpin

Princeton’s Food Scraps Drop-Off Program is growing fast, with dozens of new participants, three new drop-off sites added last month, and increasing opportunities for residents to do their part to reduce their carbon footprint.

Assistant Municipal Engineer James Purcell reported to Princeton Council last week that new collection bins were installed on March 5 at Riverside Drive adjacent to Riverside Elementary School, at Magnolia Lane adjacent to Littlebrook Elementary School, and on General Johnson Road adjacent to the sanitary sewer pump station and Johnson Park Elementary School.

As of Friday March 28, Purcell stated, an additional 36 people had signed up for the program, which now serves 321 Princeton residents at the three new sites along with the original locations at the Municipal Building on Witherspoon Street and at Monument Hall on Monument Drive.

“We have received very positive feedback about the new collection bins and look forward to greater participation and expansion of the program to the full buildout of 12 sites in the coming months,” said Purcell.

He noted that one of the locations for future bins will be convenient to the tree streets, whose residents now are using the bin at the Municipal Building.

The program is currently diverting more than two tons of food waste from the landfill per month, delivering it instead to Trenton Renewables, where it is converted into biogas for energy production and a soil amendment for farming.

Purcell pointed out that in addition to avoiding the methane gas that is 20 times more damaging than carbon dioxide and is created when food scraps decompose in a landfill, the municipality saves about $70 per ton in costs. The program is partially funded by a grant from the U.S. Department of Agriculture.

“Greenhouse gas reduction is the main reason we’re doing this,” said Purcell, who pointed out that Princeton is the only town in Mercer County with a food scraps drop-off program, but there are other programs in other parts of the state.

Sustainable Princeton Program Manager Jenny Ludmer, who works with the municipality on this program, discussed the value of the program and some of the types of composting that residents are using to divert their food scraps from the landfill and to avoid the damages of methane.

“A much more environmental option is to compost them in your backyard, feed them to backyard chickens, use a vermicomposting system [with worms], mix them bokashi [a food waste conversion process], or pay for a curbside pick-up from several different vendors, but those options aren’t available to everyone,” she said.

Citing the growing participation in the program, she continued, “What’s unique about Princeton’s new food scrap drop program is that every Princeton resident can participate for free, whether they rent or own a home. The five drop sites currently available offer many residents convenient locations to participate in this program and do their part to reduce their carbon footprint.”

The municipality’s evaluation indicates that diverting food scraps from landfills can reduce Princeton’s carbon emissions by 8.4 metric tons of CO2 equivalent per food scrap drop site each year.

To sign up, residents should go to princetonnj.gov/1425/Food-Scrap-Drop-Off-Program and follow the link to register and complete a short quiz to make sure that the rules and regulations are understood. Approval from the municipality is necessary in order to use the drop-off bins, as the town wants to make sure the bins are being used properly and that there is no contamination.

“Trenton Renewables, where we take the food scraps, has never detected any contamination from Princeton,” said Purcell. “We’re very specific about what you can and cannot put into the bin.”

The Welcome Packet for drop-off program participants advises that only food scraps are accepted through this program — no bags, no garden clippings, no pet waste or litter, no pizza boxes, no paper cups or plates, no compostable cutlery or serviceware.

The program overseers recommend that participants use an old tin or plastic container to collect and store food scraps at home, keeping them in the refrigerator or freezer to prevent smells or attracting pests.

Each week municipal staff transports carts from the drop-off sites to Trenton Renewables, a food waste recycling and renewable energy company which uses anaerobic digestion to create energy from food scraps, as well as a digestate that can be used as a soil amendment in agriculture.

From 2010 to 2019 Princeton did offer a subscription curbside organics collection program to a number of residential households, but the program was concluded due to rising collection costs and insufficient compost facilities in close proximity.

With the development of nearby facilities, Princeton solicited bids in 2022 for curbside food scraps collection, but the only bid received would have doubled the rising cost of solid waste disposal and was rejected by Princeton Council.

A municipal waste team, including municipal staff, Sustainable Princeton, and a citizen member of the Princeton Environmental Commission has met regularly to consider options for Princeton and to learn from other municipalities.

Questions about the food scraps program can be directed to the Princeton Waste Team at wasteinfo@princetonnj.gov.