Philadelphia Aims at Food Waste with In-Sink Disposal Law

Philadelphia is now requiring that new residential construction include in-sink food waste disposers, in an effort to increase food waste diversion.

The city’s building code amendment was signed into law Dec. 23 and took effect Jan. 1.

"While residential recycling rates have tripled over the past eight years, reducing the amount of food waste in the city's waste stream is critical to meeting more aggressive waste reduction goals,” said outgoing Mayor Michael Nutter, in a news release. “In-sink food waste disposers are a helpful tool as the city continues to explore opportunities to divert organic material from the waste stream." 

Expanded use of food waste disposers address all of Philadelphia’s GreenWorks sustainability goals–reducing waste, generating renewable energy and decreasing greenhouse gas emissions. The law was sponsored by outgoing City Councilmember

Dennis O’Brien and supported by several city agencies, as well as the Building Industry Association, representing the residential development sector.

Communications firm Gaia Strategies has worked with the city on the project. “Philly’s willingness to bust through agency silos to envision household food scraps as a liquid resource is what led to this policy breakthrough,” says Kendall Christiansen, principal with Gaia and former senior consultant to InSinkErator, in an e-mail. “Cities with similar water resource infrastructure–producing both biogas and biosolids for good use–are looking at disposer-friendly policies and programs as part of their organics management toolkit.”

Philadelphia is targeting 10 percent of its residential waste with the new requirement. It emerged from a demonstration project conducted 2012-13, when in-sink disposers were installed in 175 homes in two neighborhoods. The program reduced food waste from those homes by an average of 35 percent. The city concluded from that pilot that it could significantly reduce the city’s trash while improving the quality of life, by reducing odors and vermin.

The city will use its existing water resource recovery infrastructure, which is based on food averaging 70-percent water. In-sink disposers convert food scraps into a slurry that passes easily through wastewater pipes and sewers, sending it to water resource recovery facilities that process clean water and recover organics for processing into biogas and fertilizer products. Philadelphia recently invested $50 million in its North Treatment Plant to upgrade anaerobic digesters that produce and use biogas from organic wastes. Baltimore-based Synagro Technologies Inc. will then produce and market the Class A fertilizer products.

The Philadelphia Streets Department’s recycling division led the project, which was supported by the Philadelphia Water Department and InSinkErator, a leading manufacturer of food waste processing systems.

There are few organic waste collection systems in dense urban areas, especially in multi-family buildings. Disposers serve an estimated 60 million U.S. homes and apartments as an environmental appliance option.

Legislation on the food waste front was a hot issue at the end of last year. In Congress a food waste recovery bill was introduced that aims to reduce food waste at both the consumer and commercial levels, and would encourage various composting and waste-to-energy (WTE) initiatives.

Rep. Chellie Pingree (D-Maine) is sponsoring the bill, which would address food waste in four areas–at the consumer level, in grocery stores and restaurants, in schools and other institutions, and on farms. The bill would encourage composting as a conservation practice eligible for support under the U.S. Department of Agriculture. It would support food WTE projects at the farm, municipal and county levels, while ensuring that edible food that could feed hungry people would not be diverted to energy production.

In California five laws took effect at the beginning of the year to further organic waste management and recycling. Those laws involve mandatory commercial organics recycling, tax exemptions for recycling and composting equipment, detailing organics infrastructure, recycling and composting reporting requirements and composting promotion.

New York City is another densely populated city that has wrestled with the in-sink food digester issue. Last March the New York League of Conservation Voters Education Fund (NYCLV) has made recommendations to New York City on how to improve its organic waste diversion. Among the recommendations was the consideration of means to encourage the use of in-sink organic material grinders in certain multifamily districts.