Context

The City of Durham is located in central North Carolina and is part of the region known as the "research triangle," named for the three large research universities in central North Carolina (Duke in Durham, University of North Carolina in Chapel Hill, and North Carolina State University in Raleigh) in addition to the abundant technology and life science companies headquartered in the area. It is located nearly equidistant from the beaches and outer banks of the east coast of North Carolina and the Blue Ridge and Smoky Mountains of western North Carolina.

Durham originated as a railway depot and was the headquarters of the American Tobacco Company in the 20th century. It was also home to one of the US's first "Black Wall Streets" located on Parish Street, which housed North Carolina Mutual Life Insurance Company and Mechanics & Farmers Bank, two of the most influential Black-owned businesses of the 1900s.

Today, the "Bull City" is home to nearly 300,000 residents and is one of the fastest-growing cities in the region. The City is extremely diverse, with a population that is close to 40% white, 36% Black, 15% Hispanic, and 6% Asian. 

Durham is a progressive City and prioritizes climate considerations in its governance. In 1996, the City passed a resolution to join the Cities for Climate Protection (CCP) and in 2007, Durham was the first community in North Carolina to develop a Greenhouse Gas (GHG) Emissions Reduction Plan.

Precedents

The genesis of our practice, a curbside food waste collection service in Durham, stemmed from a waste reduction initiative embedded in the City's Strategic Plan. Informed by a comprehensive 2015 waste characterization study revealing that a staggering 30% of residential waste in Durham is compostable, it became evident that landfilling such material posed multifaceted challenges - economic, environmental, and social.

The economic rationale was compelling: landfill costs, already steep, were projected to rise significantly with the need for additional landfill space, each acre costing over $1 million to construct. Meanwhile, the environmental impact of landfilling, notably methane emissions contributing to climate change, and the disproportionate siting of landfills in minority communities, underscored the urgency for a sustainable solution.

Historically, Durham provided limited composting avenues, mainly through sporadic educational events on backyard composting. Residents, however, lacked a viable option for curbside food waste collection, with private services imposing monthly fees. This glaring gap propelled our city's commitment to equity and sustainability, driving the quest for a community-driven, no-cost curbside composting service.

In essence, our practice emerges from a confluence of data-driven insights, fiscal prudence, environmental stewardship, and a steadfast commitment to justice, underscoring Durham's ethos of innovation and inclusivity.

Methodology

The practice started in 2019 with a citywide survey and subsequent resident interviews. Our team gathered survey responses from nearly 4,500 residents, held in-depth interviews with six of the survey respondents, hosted two focus groups with collections staff, and completed a benchmarking analysis, examining other cities' programs and speaking with staff who helped develop them.

In mid 2019 through early 2020, the team prototyped the service by developing a minimum viable product (MVP) version of the program and recruiting two groups of residents to participate in two, two-week prototypes. Residents were provided with countertop food scraps containers, communications materials, and a texting line to answer questions. After two weeks of trial service, they were interviewed. The insights from this prototype, including logistical hurdles, communications misunderstandings, and resident feedback on the equipment and educational materials all helped refine the program before scaling.

Using the findings from the previous exploratory work, the team recruited ~100 households in a diverse neighborhood to experience full-scale service with weekly pickups. This allowed the solid waste team to iron out program logistics and driver training and offered more residents the chance to provide feedback through their set-out behavior as well as surveys and interviews.

To rigorously evaluate the impact of the program, the team launched a randomized controlled trial (RCT) in late summer 2023, after recruiting 360 households to participate from four neighborhoods around the City. Approximately half of those recruited were provided full-scale composting service for 16 weeks, during which time the weight of their household garbage was measured on a weekly basis, and they provided responses to three surveys. Their results were compared to a "control" group who did not receive curbside service until the end of the 16-week pilot.

Commmunication

Communication for this practice was a multi-channel approach, with creative strategies implemented for recruitment, feedback, and participant education. To recruit participants for the survey, prototype, and pilots, the team advertised on social media and through interested community groups (such as community gardens and citizen environmental boards). We also delivered flyers to homes in targeted neighborhood, garbage collectors placed tags on resident garbage carts, and the City's 311 center sent texts to residents.

The team established a text helpline for the prototypes which residents used to ask staff questions. The data from the helpline informed a centralized FAQ website for the larger pilots. Finally, we studied how participation in a municipal compost program might lead to spillover of other community and environmentally-friendly behaviors and sent residents postcards with tips to reduce water use and participate in civic events and thank-you gifts to spur reciprocity.

Innovation

The most innovative aspect of the practice is our iterative and inclusive approach. We began with pre-testing, launching a citywide survey and qualitative research to understand residents' needs and challenges. This led to prototyping, where small-scale trials were used to gather feedback and refine the program design.

Building on these insights, we proceeded to a comprehensive approach that integrated human-centered design and rigorous evaluation. This included a year-long 100 house pilot and a 16-week randomized controlled trial with 360 households to measure landfill waste reduction. Crucially, our program extends further to examine spillover behaviors, aiming to foster broader environmental consciousness and community engagement.

Finally, our engagement with garbage collections staff ensured that operational insights were integrated into the program design, enhancing its effectiveness. This collaborative effort empowers staff and contributes to advancing the industry as a whole.

Evaluation

The practice was evaluated through diverse and comprehensive mechanisms to ensure thorough assessment and resident involvement. At every stage, qualitative outcomes were meticulously monitored, including participant comfort, ease, and attitudes, through a combination of long-form onboarding and offboarding surveys and weekly pulse surveys. Additionally, in-depth interviews provided valuable insights into the lived experiences of participants. 

To gauge behavior change, we measured the volume of garbage being sent to landfill using scales on collection trucks, providing tangible data on waste reduction. Spillover behavior was assessed through metered water usage and sign-ups for community events, offering insights into broader environmental consciousness and community engagement fostered by the program. Throughout the evaluation process, resident feedback remained central, serving as a guiding force in shaping the program's trajectory.

Impacts and result

Through this practice, the team achieved significant diversion of waste and positive effects on resident satisfaction and identities. In the first year of the qualitative pilot, participants diverted 30,000 pounds of food waste from the landfill, reducing greenhouse gas emissions by nearly 60 tons. The results of the next phase (the RCT) showed that providing curbside food waste collection to residents reduced their weekly trash volume by 5.8 pounds. If this service were scaled to all households in Durham, this could prevent 14,000 tons of waste being sent to landfill every year.

Beyond the environmental achievements, this practice also demonstrated a high level of interest and positive assessment from residents. In surveys, residents who were provided this service showed more positive perceptions of their local government and impression that their voice matters in decision-making, highlighting the broader social benefits of the practice. This likely stems from alignment between residents' environmental values and the City's actions, reinforced by human-centered design methods emphasizing resident feedback. 

 In the City's annual resident satisfaction survey, 70% of residents stated they would be interested in a curbside food waste program and another 15% were already participating in composting in some form. In addition, hundreds of residents have signed up to be alerted when the practice is able to scale to their communities.

Experience overview

Designing and testing a curbside food waste collection program in Durham, NC required marrying behavioral science, community-centered design, and rigorous evaluation to achieve significant waste reduction and environmental benefits for residents.

Durham is a vibrant city known for its rich cultural heritage, progressive values, and commitment to sustainability. Durham prioritizes community engagement and empowerment, striving for equity and inclusivity.

The genesis of our practice, a curbside food waste collection service, stemmed from a waste reduction initiative embedded in the City's Strategic Plan. Recognizing the economic, environmental, and social challenges posed by landfilling compostable waste, Durham embarked on a journey to create a community-driven, no-cost curbside composting service. This innovative approach emerged from data-driven insights, fiscal prudence, environmental stewardship, and a steadfast commitment to justice, reflecting Durham's ethos of innovation and inclusivity.

Our methodology started with a citywide survey and resident interviews, followed by prototyping, full-scale implementation, and a randomized controlled trial to measure impact. Throughout all phases, this practice employed a multi-channel resident communication approach, utilizing social media, community groups, flyers, text helplines, and postcards to engage residents. The most innovative aspect lies in our iterative and inclusive approach, integrating human-centered design, rigorous evaluation, and engagement with garbage collections staff to enhance program effectiveness.

Specific groups targeted include diverse residents and garbage collectors, ensuring comprehensive representation and empowerment. Evaluation mechanisms encompassed qualitative surveys, interviews, and quantitative data on waste reduction, spillover behaviors, and resident feedback.

The impact of our practice has been substantial, with significant waste diversion, reduced greenhouse gas emissions, and positive effects on resident satisfaction. Over 30,000 pounds of food waste were diverted from landfills in the first year, with a potential annual reduction of 14,000 tons if scaled citywide. Residents showed increased positive perceptions of local government, indicating broad social benefits beyond environmental achievements. The practice has contributed to institutionalizing participatory democracy in Durham, fostering a culture of environmental stewardship among residents.

Images