UC Waste Behavior Change Study

28 January 2026
zero waste bins (recycle, compost, trash) in the UM university center with new shadow boxes showing correct way to short
New shadow boxes above zero-waste stations show students the correct way to sort their waste.

Last spring, UM unveiled its "Zero By Fifty" Zero Waste Plan. In this plan, we highlighted 10 goals that align with Missoula's vision of achieving zero waste by 2050, with several key focus areas across campus. To learn more about the specific goals and focus areas, visit our Zero Waste Plan page.

The goal of the UC Behavior Change study was to test and demonstrate how changes in infrastructure and engagement can affect diversion and contamination in compost. 

Timeline of the StudyInfographic illustrating the timeline and results of a UC Behavior Change Study, highlighting compost diversion increases, sample volumes, and changes in infrastructure engagement from Fall 2025.

Spring 2025: Three compost audits were completed to collect baseline weights and volumes. 

Fall 2025: During the fall semester of 2025, weekly compost samples were audited from the UC Food Court. Data collected included weights, volume, and an itemized accounting of the number and types of compostable materials collected in addition to the incidences of contamination. Landfill samples (weight and volume) were taken and audited on November 13th, 14th, and 17th.

Nov. 18th to Dec. 9th, 2025: During this time period, weight and volume measurements for compost and landfill were collected daily to determine if increased infrastructure and engagement were making an impact. New infrastructure and engagement methods include: 

  • Removing eight standalone landfill bins from the UC Commons
  • Added three additional zero waste stations (compost, recycling, and landfill)
  • Signs that reflect food court items were updated for all zero waste stations
  • Introduced shadow boxes (with actual food court items) on zero waste stations to show students how to sort waste correctly
  • Added three large sandwich boards with composting signs
  • Provided additional sorting sorting instructions on posters
  • Installed vendor specific signs for each business in Food Court

Results of the Study

During this three-week period, these are the results we saw from increased compost infrastructure and engagement. 

  • Compost diversion increased from 7.8lbs to 27lbs per day. This is a 246% increase!
  • The 24th of November was the tipping point where compost levels exceeded landfill levels daily.
  • Contamination levels remained consistent overall while diversion increased.
  • Peak diversion of compost was 58% compared to landfill.

Conclusions & Moving Forward

As a result of our findings, the changes in infrastructure and engagement strategies are likely to become a permanent fixture of the UC Commons. Though we are pleased with the increased landfill diversion, we will continue our efforts to reduce contamination through manual top sorting, maintaining updated signage, and utilizing engagement strategies. We anticipate the results of this study will be helpful to apply to other buildings and applications.