Air Quality in Courtenay

The provincial air monitoring station at Courtenay Elementary School has been collecting data since 2011, and tracking how conditions have changed at this location over time.

To understand how air quality varies across the region, additional PurpleAir monitors have been installed by the City as well as local organizations and residents. These monitors report real-time measurements of fine particulate matter, and report them on an online map available here.

Measurements are compared against BC Air Quality Objectives, which specify the maximum allowable concentration of pollutants.

What we have learned from air monitoring:

  • The average annual concentration of fine particulate matter, a key ingredient in smoke, has been dropping since 2017, which indicates the air is less smoky on average.
  • While the improvement can’t be attributed to a single factor, likely reasons for this trend are increased regulation of slash burning and reduced use of wood burning appliances.
  • Daily spikes of fine particulate matter occur during winter evenings and early mornings from October to March. During these times, air quality does not meet the BC Air Quality Objectives. 
  • The pattern seen in the air quality readings is consistent with the time of day that people are likely to be home and using wood burning appliances.
  • On winter nights, there can be wide variation between the monitor readings. Older neighbourhoods, with more homes equipped with wood burning appliances, consistently have the highest readings of fine particulate matter. 
  • The location of wood burning appliances in our neighbourhoods, makes them more impactful on individual health than other sources of smoke that originate far away (such as wildfires in the summer months).
  • Our location tucked between the mountains and ocean is beautiful – but at night, these features create atmospheric conditions that trap pollutants close to the ground.


For more information about monitors and readings, visit our Air Quality Monitoring page.

AVERAGE HOURLY MEASUREMENTS: Looking at the average hourly concentrations of PM2.5 during a typical winter day, we can see that after 5 p.m., fine particulate matter exceeds BC air quality objectives, peaking at 9 p.m., and remains elevated until early morning

 

AVERAGE MONTHLY MEASUREMENTS:.The graph below shows the average monthly concentrations of PM2.5. During the winter, from mid-September to mid-March, concentrations of PM2.5 exceed the BC Air Quality Objectives. This timing aligns with the seasonal use of residential wood burning appliances.