Adopt-A-Street Cost/Benefit Analysis
The presence of litter in communities, while sometimes perceived as insignificant, can have a major impact on the local environment. Litter can affect soil and water quality, wildlife, and community member perceptions of their neighborhoods. Litter prevention programs serve both to educate residents about the scale of the problem and to empower them to remove detrimental litter in their communities. Litter prevention programs are particularly visible at the state level, where programs like Adopt-a-Highway and anti-littering messaging are seen on interstates and highways. This work is also conducted at the local level for streets and roads.
The City of Durham’s Adopt-a-Street (AaS) program leverages volunteer personnel to remove litter from the City’s roadways. The program is administered by the non-profit Keep Durham Beautiful (KDB), which is part of the Arts, Culture, and Sustainable Communities Division of the City’s General Services department. KDB is an affiliate of the national organization, Keeping America Beautiful. Department leadership engaged the Innovation Team to conduct a cost-benefit analysis and evaluate future projections of the program as a part of the City’s 2022-23 Continuous Improvement work plan.
The goals of this analysis included:
- Assessing the current state of litter prevention across various City of Durham departments
- Understanding the program’s strengths and challenges from the perspective of both staff and volunteers
- Gathering the quantitative and qualitative effects of the program on the Durham community
- Quantifying the program’s costs and benefits using rigorous methodology, recognizing the complexity inherent in quantification of public benefits
- Highlighting any findings or recommendations that emerge from this analysis
The I-Team first conducted a general exploration of literature on programs in the space and related litter findings. While litter is certainly an aesthetic concern for the public, it is also environmentally hazardous. Cigarette butts and microplastics, two of the most commonly littered items, can cause harm to soil, groundwater, streams, and wildlife. Studies also show that high litter presence has been associated with a higher impression of crime in neighborhoods, a decrease in property values, and a moderate association with depression, positing a wide array of social concerns.
The I-Team grouped the relevant costs of Durham’s Adopt-a-Street program as personnel, materials, and general program expenses. In terms of personnel, the program employs two positions: an AmeriCorps member serving with KDB and the executive director. The staffing costs were calculated using total compensation for the positions, including salary, taxes, healthcare and retirement considerations. Materials include supplies given to volunteers as well as the costs of tools unreturned. Other material costs include the fees for making and installing signage and the various program management softwares. As far as intangible costs, personnel safety risk associated with the program’s activities cannot be quantified but exists and are extenuated with the expansion of the program.
For benefits, the I-Team gathered both quantitative and qualitative measures. For a quantitative analysis, the team measured the effects of the program with two different methods.
For Method 1, the team conducted an analysis of the program’s litter reduction. From March 2022 to February 2023, The amount of litter collected by the program was measured at each cleanup event. The I-Team counted the total amount collected over the year in pounds and used the 2022 NC Department of Transportation cost estimate of litter removal per pound to calculate a dollar benefit of the program’s work.
For Method 2, the I-Team deducted a quantitative benefit from the value of volunteer time. The Adopt-a-Street program uses volunteer work to produce litter reduction, which when quantified against paid work, has a significant fiscal impact/difference/disparity. The team used figures from volunteer records as well as a survey conducted in April 2023 to calculate the number of person-hours worked per year. These figures included the number of events held, the number of participants at each event, and the number of hours conducted at each event. Using conservative national and state estimates of the volunteer time’s monetary value, the team calculated the value of volunteer hours in the program.
In 2022, the Keeping Durham Beautiful team conducted a benchmarking analysis of the program with 21 comparable organizations, 18 of which were municipalities. Compared to others, Durham’s program has one of the highest clean-up frequency requirements. Most of the programs (74%, 14 organizations) required four or fewer clean up events a year, while Durham’s Adopt-a-Street program requires monthly commitments. Only about half of the programs (52%, 11 programs) had the same 1-mile minimum street length requirement as Durham. Most programs, like KDB, were over 10 years old.
The I-Team also distributed a survey to Adopt-a-Street volunteers to assess their experiences and attitudes towards the program. In total, the online survey garnered 47 responses from 15 different groups. 44 of the respondents (94%) rated their experience in the program as “very positive” on a 5-point Likert scale. When asked about their motivations, The top three were concern for the environment, concern for neighborhood appearance, and positive feelings coming from the work itself. The survey also assessed volunteers’ feelings towards the program’s requirements for frequency of events, distance, and reporting. Volunteers responded positively, with 93% saying the once a month and 91% saying the street length requirements were just right. The team also wanted to explore scenarios regarding supply distribution that have been implemented with success in other municipalities. 67% of volunteers said they would be either somewhat or very likely to continue in the program if they had to pick up supplies before the event, while only 53% said they would be as willing to pay to keep supplies on hand.
The survey asked respondents a series of open-ended questions to gather a qualitative response. When asked what they enjoy about volunteering, volunteers most frequently referenced neighborhood appearance or cleanliness (13 mentions), followed by social benefits, the ease of participation, and the ability to help others (9 mentions each). When asked about how they believe the community benefits from Adopt-a-Street, respondents cited neighborhood appearance and cleanliness the most frequently (20 mentions), followed by environmental and social benefits (7 mentions each).
Total costs breakdown
For staffing, AmeriCorps members tracked their hours spent on Adopt-a-Street tasks and the KDB Executive Director provided an estimate of theirs. The AmeriCorps member spent 178 of their estimated 1,875 annual hours working on the program. This amounts to $1,938 per year out of the total $20,500 cost share the City pays for the position. The KDB Executive Director was estimated to spend 100 of 1,875 hours working on the program, amounting to $5,711 for City costs. In total, staffing costs for Adopt-a-Street are $7,649 per year.
For supplies, the average cost per person for litter kits — which includes litter grabbers, safety vests, gloves, trash and recycling bags — is $35. The total estimate of supply costs over the course of one year is $3,027.
For software, the program uses ArcGIS (ESRI) to track geographic data and Salesforce for managing volunteer contacts. The City owns ArcGIS (ESRI) licenses and the cost for Adopt-a-Street is estimated based on the hours the analyst specifically used on the program. While the license cost $500, only 8 of the analyst’s 875 hours are spent on AaS. This amounts to $2.13 per year for the software and $545.54 per year for GIS analyst compensation, for a total of $548 for software costs.
For signage, costs include production, installation, material costs, staff time costs, and mileage costs. With approximately 7 signs installed per year, the total costs amounts to $6,364.80 per year— with material signs and poles costing $1,000 and KDB branded signage costing $60.80 per installation. For mileage, the program expends an estimated 70 miles per year for sign installation and maintenance, which costs $45.85 in reimbursements. For staff costs, maintenance technicians work 220 annual hours for a total of $8,209.99. The total estimate for signage and maintenance costs is $15,438.24 per year.
Adding up staffing, supplies, software, and signage costs, the total quantifiable annual costs of the Adopt-a-Street program are $26,844.
Quantifiable benefits breakdown
For Method 1, Adopt-a-Street volunteers were found to have collected 10,914 pounds of litter throughout the City. In any given month, an average of 7.75 cleanup events were held and 893 pounds of litter were collected. Using the NCDOT litter removal cost estimate of $1.93/lb, it is estimated that the total value of litter removed with the Adopt-a-Street program is equivalent to $21,037 per year.
For Method 2, the team used the average of the two reported participation numbers and event times, 6.84 volunteers, each spending 1.84 hours per event, respectively. With 93 total events held, it is estimated that the program expended 1170.46 person-hours per year. Using the 2022 national value of volunteer time ($31.80 per hour), the program saves $37,220.65 per year. Using the 2022 North Carolina estimated value (29.86 per hour), the program saves $34,949.96 per year through volunteer hours.
To gather the personal qualitative benefits of the program, the team engaged both volunteers and Durham residents. In a survey distributed to both volunteers and non-volunteers, the team hoped to gauge differences in sense of community, positive relations, and purpose in life between those involved in the program and those who were not.
After excluding respondents who regularly volunteer with other organizations, the team observed a 9% higher sense of community among Adopt-a-Street volunteers compared to non-volunteers — suggesting that one benefit of regular volunteer work may be fostering a greater sense of community among volunteers. Adopt-a-Street volunteers also reported higher sub-factors of community, in needs fulfillment and emotional connection, than the general population.
The team also sought to gauge neighborhood appearances and impressions through a resident survey. Those who live on adopted streets felt that litter was a more significant problem, both on their streets and generally in Durham, compared to those who live on not-adopted streets. This may be due to the added emphasis on litter brought to the area from the program, or that the program requires streets to have a significant litter presence to be adopted. Significantly, residents who live on adopted streets reported littering themselves at a far lower rate than those not living on adopted streets — 15% compared to 33%. This may indicate the program acts as a behavioral nudge for residents, who see regular cleanups and are discouraged to litter themselves.
Adopt-a-Street is not the only volunteer litter prevention program administered by Keep Durham Beautiful. KDB also operates Big Sweep, Creek Week, and general individual and group cleanups. In comparison with these programs, AaS accounts for approximately 11% of the total volume of litter removed.
Why it Matters
The Adopt-a-Street program does work to directly benefit the Durham community. The program removes a significant amount of litter and provides positive intangible effects on volunteers and neighborhoods. As the City evaluates the program and plans for the future, this analysis will provide a benchmark to examine expansion. Specifically, the study will help future programming considerations surrounding signage cost and use.
The study also has research implications. While many previous studies have developed methods and measures for quantifying the costs of litter removal, few focus on quantifying the benefits of litter cleanup programs like Adopt-a-Street. It is generally difficult to measure the way the public benefits from such programs and this provides a demonstration of how one might. The methodology laid out in this case study could be adapted to other events administered by cities that incorporate volunteering into their operations.