The Clean Air Strategic Alliance (CASA) is a multi-stakeholder partnership. It is composed of representatives selected by industry, government, non-government organizations, and participating First Nations and Metis communities to provide strategies to assess and improve air quality for Albertans. CASA uses a collaborative consensus-based process, and every partner is committed to a comprehensive air quality management system for Alberta.
Air pollution from Alberta’s transportation sector is a growing concern, impacting both the environment and public health. In 2018, CASA launched the Roadside Optical Vehicle Emissions Reporter (ROVER) III Project to tackle this issue by gathering critical data on vehicle emissions across the province. This innovative study used remote sensing technology to measure emissions from nearly 50,000 light-duty gasoline vehicles and over 6,000 heavy-duty diesel vehicles, providing much-needed insights into Alberta’s air quality challenges.
The study showed that 30% of the heavy-duty vehicles measured emitted at least 10 times the expected amount of nitrogen oxides, and many exceeded emissions benchmarks for several other pollutants. ROVER III did not include vehicle inspections, so the causes are unknown, but this level of excess emissions means these vehicles likely have emission control systems that have been tampered with or that are malfunctioning.
Tampering with vehicle emission control systems involves removing, bypassing, defeating, or otherwise rendering the emission control systems inoperative. Alongside Manitoba, Northwest Territories, and Nunavut, Alberta does not prohibit tampering or require checking emission control equipment as part of commercial vehicle safety inspections.
Exposure to diesel exhaust is associated with several types of cancers, along with respiratory and cardiovascular problems. A 2022 International Council on Clean Transportation study estimated that a tampering incidence of just one percent among heavy-duty diesel vehicles in Canada will result in 690 excess premature deaths and 11,700 disability-adjusted life years (years lost due to ill health, disability, or early death) over the next 20 years in the country.
By identifying high-emitting vehicles and highlighting regulatory gaps, CASA’s findings lay the groundwork for stronger emissions management policies and cleaner air for Albertans. Their work directly benefits vulnerable communities—particularly children, the elderly, and those with respiratory conditions—who are most affected by air pollution. With a focus on science-driven action and collaborative problem-solving, the ROVER III Project is paving the way for a healthier, more sustainable future.
Financial support for this project was generously provided by Alberta Environment and Protected Areas, the International Council on Clean Transportation, the Canadian Fuels Association, and Alberta Transportation and Economic Corridors.
