Milk Dispensers by the Numbers
This has been a big year. Partnering with five schools in four different districts, we conducted a pilot project to see if milk dispensers could help reduce cafeteria waste. Through a grant from the Washington State Department of Ecology, we provided schools with dispensers and washable cups to serve milk in instead of cartons. We measured milk and carton waste before and after the dispensers were installed. With the end of the school year approaching, we just finished up our final waste audits and the results are in.
Figure 1. Milk waste comparisons before vs. after the dispensers were installed
• All 5 schools showed a reduction in milk waste (figure 1) ranging from 1.15 to 7.25 gallons per day, with an average reduction of about 70%.
• Using this data and assuming 180 days in a school year, these schools prevented an average of 548 gallons of milk from being wasted each year!
• It takes 144.2 gallons of water to produce 1 gallon of milk1. Preventing 548 gallons of milk waste means saving 79,021.6 gallons of water.
• The carbon footprint2 of 1 gallon of milk is 17.6 pounds of CO2. Preventing 548 gallons of milk waste also means reducing greenhouse gas emissions by 9,644.8 pounds, or the equivalent emissions from driving 10,696 miles in an average car3.
Table 1. Carton waste comparisons before vs. after the dispensers were installed
*Assuming 180 days in a school year
• All schools showed a significant reduction in carton waste (table 1), with 4 out of the 5 reaching 100% reduction.
• Milk cartons are often tricky to recycle
, and reducing their use can have environmental and economic benefits
Milk cartons at Lacamas Lake
Milk waste before the dispenser
Milk waste after the dispenser
Overall, the milk dispenser pilot project showed success in reducing milk and carton waste. It has been a wonderful learning experience and we want to give a huge thank you to all of our partner schools! We look forward to expanding this project, gathering more data, and continuing to try new waste reduction strategies. Contact Michelle at Michelle.Picinich@clark.wa.gov
if you have questions or want more information about the project.
1. Innovation Center for U.S. Dairy. (2013). U.S. Dairy's Environmental Footprint: A summary of findings, 2008-2012. June 5, 2019, https://www.usdairy.com/sustainability/environmental-research
2. Thoma, G., et al. (2010). Greenhouse Gas Emissions from Production of Fluid Milk in the US. University of Arkansas & Michigan Technological University.
3. EPA. (2017). Greenhouse Gas Equivalencies Calculator. June 5, 2019, https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator