A week after a catastrophic bus explosion claimed three lives in Calgary's northeast Saddle Ridge neighbourhood, the area's city councillor is demanding an independent investigation to ensure no stone goes unturned.
The October 15 collision involved two city transit buses and multiple vehicles, with a compressed natural gas (CNG)-powered bus erupting in flames. The blast killed three people and injured 16 others, sending shockwaves through the community and raising urgent questions about transit safety.
While Calgary Fire Department, Calgary Police Service, and Transport Canada are already conducting their own investigations, Coun. Raj Dhaliwal says an external, unbiased probe is essential to restore public confidence.
"If it's one person, two person — I don't care as long as it's done externally and there's no biases built into final recommendations," Dhaliwal told reporters Thursday.
The Ward 5 councillor wants the independent review to examine both transit-specific factors and the intersection's road design — mirroring the comprehensive approach taken following the Bearspaw feeder main ruptures.
Safety Concerns vs. Expert Reassurance
The explosion has sparked concern among transit riders about the safety of Calgary's CNG bus fleet, which comprises roughly 30 per cent of the city's total bus inventory. However, experts counter that such incidents are exceptionally rare and that natural gas buses meet stringent safety standards.
Gordon McTaggart-Cowen, a professor in Simon Fraser University's School of Sustainable Energy Engineering, emphasizes that CNG engines are engineered to withstand fire and undergo rigorous, frequent testing protocols.
"The designs are such in the regulations and the design standards that this should not have happened," McTaggart-Cowen explained. "The tanks go through bonfire tests to determine that they can withstand being placed in a fire, and that either they can withstand the fire, or that they can release the gas fast enough that they don't rupture."
Despite the tragedy, experts maintain that CNG-powered transit buses do not pose significantly higher risks than diesel alternatives, provided maintenance and inspection protocols remain consistent.
Dhaliwal stressed the importance of transparency: "It's surety to [transit users] that, hey, we did look at it. We went to the bottom of it. We did the root cause analysis and we can assure you, whatever the results we will be, if there's any recommendation, we want to implement those."
The investigation's findings could reshape Calgary's approach to transit safety and infrastructure design moving forward.
This article is based on reporting from CBC Calgary and continues developing coverage of the October 15 incident.