Mystery still lingers despite city's $450K probe into southeast Calgary odour

The City of Calgary has been unable to identify the conclusive source of a mystery odour that has been plaguing residents of southeast Calgary. 

After investigating the issue for approximately a year, the city released a report on Tuesday stating that "no single odour source was clearly identified as being the highest contributor to the odour issues in the S.E."

Instead, the findings appear to point to several potential sources of the smell that could be acting together or separately.

"Odours are just notoriously difficult to track, so if we get a call from a citizen, by the time we get out to investigate the odour can be gone," said Craig More, an engineer and project manager of the City of Calgary's investigation. 

"People experience odour strength and whether it's pleasant or unpleasant very differently, and our citizens can't take a picture and send it to us. So it's something we have to catch in the act, so to speak." 

The city began investigating last summer after receiving a high volume of reports of a lingering foul smell from residents in several communities in southeast Calgary, including New Brighton, Copperfield, McKenzie Towne, Douglasdale and Douglas Glen.

Citizens have described the smell as "sour" and "rotting."

 The city councillor for the area, Ward 12's Evan Spencer, said he's heard complaints that the smell resembles that of spoiled compost or fecal matter. 

The city's investigation focused on the Shepard Complex, an industrial zone that encompasses a composting facility, the Shepard Biosolids Lagoons, and a landfill site.

According to More, the investigation included multiple site visits by different experts and air sampling computer modelling, at a cost of just under $450,000. 

While the investigation failed to pinpoint a singular source for the smell, the report highlights different mitigation efforts being undertaken by the city to try to alleviate impacts on nearby residents. 

These include operational changes within the Shepard Complex, some of which have already been enacted, said More, such as limiting the amount of compost stored outside.

Additional measures, such as completely relocating the operations within the Shepard Complex were not recommended, "due to low effectiveness or impractical impacts on operations," according to the report. 

In order to further attempt to pinpoint the source of the smell, More said the city is looking at installing a series of air monitors that will be able to detect chemical compositions in the air that are known to cause odours. Investigators will then be able to compare these findings with potential origin sites.

"We'll combine that [technology] with what we're hearing from neighbouring citizens as to when the smell is really bad and when they are most being bothered," said More.

"It will allow us to even further focus efforts and resources on the worst offenders."

Spencer said the findings in the report have underlined the complexity of solving the issue, but that he will continue to push the city to take steps in the right direction. 

"I would just say to folks, I care about this, I genuinely do," said Spencer. 

"When [people] make that [home] investment, it's tied to their financial future, their livability, their day-to-day. Right now a small segment of our city, their livability has been greatly reduced because of this issue. So I take it seriously."

More was unable to give a timeline for when the issue will be resolved. 

"It's a busy, busy area of the city with multiple agricultural, industrial city operations. It's really difficult to say whether it will be fully addressed," said More. 

"The city is committed to doing what we can to mitigate and reduce the impact on neighbouring citizens, but the likelihood of there always being odours in all parts of the city is always there."