Dorval residents press for answers over shutdown of airport air-quality station

A dispute over the shutdown of an air-quality monitoring station at Montréal-Trudeau International Airport is continuing in Dorval, where residents are pressing the city and Aéroports de Montréal (ADM) for answers about when monitoring will resume and how pollution around the airport is being measured.

Station 66, located on airport property in Dorval, is part of the City of Montreal’s Réseau de surveillance de la qualité de l’air (RSQA). It is not an airport-operated station.

Dorval Mayor Marc Doret previously explained the situation this way:

“The Montréal air quality monitoring station (Station 66), previously located on Aéroports de Montréal (ADM) property, was recently removed as a result of ongoing airport construction projects.

“The City of Dorval is working closely with ADM and the City of Montréal to explore options for relocating the station within Dorval, should a suitable site be identified. Air quality monitoring remains an important tool for understanding local environmental conditions, and all partners are committed to finding a location that meets the technical requirements necessary to continue this important service for our community.”

Doret also clarified that the stations on the Island of Montreal are managed by the Service de l’environnement de l’agglomération de Montréal, rather than by Dorval or ADM.

Historical municipal records show Station 66 has been on airport grounds for decades and was rebuilt in 2013 after Montreal obtained the necessary airport authorizations.

The station gained importance after Montreal installed an ultrafine-particle (UFP) analyzer there in 2022. UFPs are particles smaller than 0.1 micrometer (µm) and are not currently regulated in Quebec.

Montreal’s 2024 air quality report found an annual average of 23,873 UFPs per cubic centimetre at Station 66, compared with 6,716 at residential Station 55. Station 66 exceeded the World Health Organization’s identified high level of 10,000 particles per cubic centimetre over 24 hours on 330 days, or 92 per cent of the year. The city cautioned that the WHO levels are targets, not regulatory standards.

The report also noted that ADM did not provide statistics showing the number of aircraft taking off and landing by hour, making it difficult to directly link pollution peaks to aircraft movements. However, concentrations at Station 66 moved closer to those at the residential station outside normal airport operating hours.

Residents say Station 66 was taken out of service in January 2026 because of airport construction. Montreal’s 2025 air-quality report indicated the station was expected to return in spring 2026. As of late August, residents said it had not been restored or relocated.

ADM confirmed construction is the reason the station remains out of service, but said the issue is now relocation rather than permanent closure.

“Due to construction activities on the airport site, the station needs to be relocated,” ADM media-relations representative Eric Forest said in an emailed statement. “ADM is actively working with the City of Montréal to identify a new location for the station.”

At the most recent Dorval city council meeting, resident Anna Campagna again raised the issue with Doret. Campagna said she had suggested that the mayor personally contact ADM president and CEO Yves Beauchamp to press for the station to be relocated and reopened.

According to Campagna, Doret told council that he had spoken with Beauchamp shortly before the meeting and that they agreed Station 66 should be reopened “as quickly as possible.” Doret also said, according to Campagna, that his director general would personally follow the file with ADM.

Campagna described that as encouraging news.

She also said Doret added commentary while reading her question about possible sources of ultrafine particles around the airport, including other transportation sources. Campagna said she wanted the focus to remain on the monitoring data collected at Station 66 and what they can show about air quality near the airport.

She pointed to Montreal’s 2025 air-quality report, which includes a section examining aviation-related pollution at Station 66.

The latest council discussion also raised concerns about air quality monitoring inside the Dorval North Arena, located close to the airport’s northern runway and used by children, families, and seniors.

Campagna said Doret also backed away at the latest meeting from a commitment he had made in February to approach the Agglomeration of Montreal about funding for UFP monitoring inside the arena.

For residents living beside one of Canada’s busiest international airports, the issue is increasingly about whether measurements are being collected where they are most useful, when Station 66 will return, and whether additional monitoring will be carried out in nearby public facilities.