Background Research

Approximately 30% of Durham’s residential waste stream is food and paper products.  Food waste is a major contributor to greenhouse gas emissions, estimated to contribute up to 8% of total greenhouse gas emissions worldwide.

The City of Durham’s Solid Waste Management Department, Innovation-team, and the Center for Advanced Hindsight are working to create a “Culture of Composting” in Durham.   Using behavioral science, human-centered design, and rigorous evaluation, we hope to design and test interventions aimed at broadening participation in composting, decreasing the amount of food and organics transported to the landfill, and creating a quality product for the community.

Qualitative Research

A 2019 survey of 4,500 Durham residents found that most respondents are very familiar with composting (58%), though over half do not currently compost (53%).  The team interviewed experts that successfully implemented municipal composting programs in other cities across the country as well as speaking with local stakeholders.  Often cited behavioral barriers to composting include future discounting, status quo bias, self-herding, default bias, positive illusions, unrealistic optimism, social norms, and friction.  Process-based barriers include a general lack of know-how and the perceived “ick factor.”

The team conducted a focus group with the City’s Yard Waste collections crew to better understand the collection experience, what challenges the crew might foresee, and how to best involve the team in the planning process.

Prototypes

Prototype A: Summer 2019

The team conducted Prototype A to better understand challenges and successful strategies centered around three main areas: (1) User knowledge and experience; (2) Contamination; (3) Equipment and collection.  Eight Durham residents were given an indoor collection bucket and a folder containing background and timeline information, participation guidelines, instructions on documenting their experience via text, and a simple composting educational flyer.  Over two weeks, participants collected a total of 127.8 pounds of food waste with few contaminants (mostly produce stickers and plastic).

Prototype B: Fall 2019

Prototype B engaged another seven Durham residents to again collect food waste at home for two weeks. The team observed resident behaviors around indoor and outdoor collection, learned from them in real-time, and closed the engagement with an interview. Insights from this experiment and participant feedback directly informed the development of the next stage of the study.

3-Phase Pilot Planning

The team plans to test in three phases: (I) Qualitative Exploration; (II) Randomized Controlled Trial; (III) Measured Pilot Rollout.  Phase I will engage 100 households to qualitatively explore methods of recruiting participants to take part in a curbside composting program and gather feedback on which strategies for reducing contamination should be tested in Phase II.  Phase II will be a randomized controlled trial with 500 households to determine whether having access to a curbside compost program impacts the amount of garbage a household sends to landfill and how to best reduce compost contamination.  Finally, Phase III will be a staggered rollout of the program to 1,000 households, aiming to scale.