Why is it Important to Conduct Waste Audits?

September 20, 2017

By Rachel Telling


Since the launch of SFU’s new Zero Waste Initiative,  the Sustainability Office, Facilities Services and student volunteers have been rolling up their sleeves to get down and dirty with the trash.  Below, we’ve outlined how and why waste audits are conducted and how they’ve helped SFU to achieve a 70% waste diversion rate within only two years of the Zero Waste Initiative’s launch.


Why are Waste Audits Important?

The primary purposes of a waste audit are:

  1. To learn how the Zero Waste program is working
  2. To identify anything that is not working correctly (e.g., if an item is consistently found in the wrong bin)
  3. To develop a plan to address deficiencies (usually through communication and education)


What are the Types of Waste Audits?

  1. Visual Audit:  A visual audit involves looking in the bins at the waste and writing down information such as fill levels and details of contamination.  They are conducted regularly throughout the year at SFU, both by staff on a casual basis and as part of the Student Sustainability Educators’ role each semester.
  2. Physical Audit:  A physical waste audit involves actually sorting through each of the four different waste streams.  They are conducted on an as-needed basis, a minimum of once annually.



How to Conduct a Waste Audit

1.    Visual Audit

  • Look in the bin and record fill level, contamination, and details of the contamination (e.g. what is in the wrong bin, how many items, etc.)


2.   Physical Audit

  • Janitors collect waste from specific locations (usually highest traffic areas) over a specific period, usually the busiest time, and label it with location and stream.  (At SFU, this includes the AQ (including Mackenzie Café) between 11am and 2pm.)
  • Staff and volunteers record the location and waste stream of each bag, weigh and record it, then separate out the contents into the correct streams and weigh and record those. 
  • By repeating this process for all the streams from each location, we build up a picture of the composition of waste making up each stream in the stations.  This allows us to determine the volume of waste going into each stream, the contamination rate for each stream, and what the actual contaminants are, so that we can target our communication and education accordingly.  We can also see whether contamination is better/worse in certain areas over others, as well as over time.



Using Waste Audit Analyses

The results of our audits have helped us to improve the Zero Waste program by redesigning communications materials and developing educational campaigns to inform the campus community of how to dispose of specific packaging types available at various SFU dining venues, and to better illustrate where items should go to reduce contamination.  


For example, our previous audits consistently showed that people did not know what to do with coffee cups - they were found across all 4 streams.  So, we worked with our waste hauler and compost processor to develop a process for collecting these as compost, and produced a comprehensive communications campaign to promote this.  As a result, contamination of coffee cups has now greatly improved. 


Next Steps:

Though much progress has been made, we will continue to conduct these audits and further improve SFU’s Zero Waste Initiative.  If you have an idea for improving the bins or wish to learn more please contact