How’s the Air on Your Street?
A glance at the streets of any town or city across Ontario will find ever-increasing numbers of commuters opting for a greener way, turning to pedal or pedestrian power. We know this is better for the planet, and we feel sure that getting physically active must be better for our health too. Of course there are occasional summer smog episodes when we have been told to avoid strenuous exercise. Aside from such episodes, we trust we will have reasonably good air quality to breathe on the streets where we walk, cycle and run our errands.
But who is actually monitoring air quality at “nose level” in urban areas? The ECO asked this question in 2007. We found that the Ministry of the Environment (MOE) runs a network of 40 stationary air monitoring stations across the province, but these stations are intentionally located away from point sources of air pollution or high traffic areas. MOE’s monitoring stations are designed to provide only “a broad regional perspective on air pollutants.” There are simply too few of them to identify hot spots or to provide reasonable coverage of Ontario’s population centres.
The ECO’s 2007/2008 Annual Report (see Air Quality Monitoring and Reporting in Ontario – Fostering a False Sense of Security) pointed out that many cities in Europe have very sophisticated air monitoring systems. For example, the Greater London Area in the United Kingdom is served by over 200 continuous air monitoring stations that provide Londoners with real-time data about local air quality. The ECO recommended in 2007/2008 “that MOE expand its air quality monitoring and reporting program to include a network of street-level monitoring stations.” MOE has yet to act on this recommendation.
MOE may not be taking the lead on street level air monitoring, but other groups in Ontario definitely are exploring the practical implications of local air pollution hot spots and traffic corridors. To understand who is working on local air quality issues, the ECO commissioned a small study in late 2009. The resulting report is available on the ECO’s website (summarized and available for download here).
The ECO learned that several large Ontario municipalities – including Ottawa, the Region of Halton, and Toronto – have been proactively assessing their local airsheds. A number of other municipalities are interested in doing the same. In places like Hamilton and Sudbury, partnerships involving industry and citizen groups are leading such work, rather than the municipality per se. Municipalities have some very pragmatic reasons for examining their local air quality. Neighbourhoods may be asking for help to cope with chronic road dust problems. Planners may need air quality information to help set separation distances between new subdivisions and highways. There may be emissions from industry causing conflicts between dischargers and nearby residents.
Municipalities have found that MOE’s provincial monitoring network of 40 stations is too coarse a screen to be helpful for local air quality concerns. For example, as of 2004, MOE was operating only a single air quality monitoring station in the Ottawa region, an area covering 2,700 square kilometres.
The City of Ottawa requested that MOE install a second station, which the ministry agreed to do. Similarly, Halton Region is served by only two MOE-operated stations, both in the southern portion of Halton, even though the region’s population is expected to grow by 400,000 people between 2001 and 2031. In 2008, the Region of Halton decided MOE’s coverage was inadequate, and decided to fund and operate a third monitoring station towards the north of the region. Similarly York Region, with a rapidly growing population of over one million people and an area of 1,700 square kilometres, is served by only one MOE air monitoring station.
Faced with limited data and limited resources, municipalities have opted for computer-generated airshed models validated by air monitoring, as helpful and relatively affordable starting tools. Computer models can provide communities with reasonable predictions and visual depictions of their local air quality issues and potential trouble spots. Over the last decade, Toronto and Halton Region have assessed their local airsheds using models supplemented by stationary and portable air monitoring, while Ottawa has assessed its airshed with satellite monitoring, supplemented by mobile monitoring and air modelling.
Communities have used this “model first, then monitor” approach to good advantage to identify or address a variety of local concerns, including high levels of particulate matter (PM10 ) along traffic corridors in Toronto and high levels of fine particulate matter (PM2.5 ) in downtown Ottawa. Hamilton has used mobile monitoring supplemented with air modelling to create a snapshot of air quality along roadways and along certain transects of the city. In Sudbury, extensive air monitoring has been used to assess air quality across the city but at significant cost.
MOE Involved, But Not Leading
MOE staff have certainly been supportive partners in a number of these locally-led initiatives, providing advice and expertise and sometimes undertaking monitoring work. For example, Ottawa’s study was supported by two MOE mobile monitoring units; MOE’s mobile unit was used for mobile monitoring conducted in Hamilton; and MOE audited Halton’s air monitoring equipment. Aside from these ancillary roles, MOE has also led two projects to assess local airsheds: one ongoing multi-year study focusing on the Clarkson airshed in the west of Toronto and another in 2006 to address road dust issues in Hamilton’s industrial area. But MOE’s efforts have been sporadic and site-specific, and not in proportion to the growing need for assessments of local air quality in urban settings.
What Municipalities Need
The ECO’s consultant interviewed public health staff in six communities to learn about their needs and priorities with respect to air quality monitoring. It should be noted that these were large and, for the most part, rapidly growing communities, such as the Regions of Peel, York, Halton and Waterloo.
This study was not designed to evaluate the air quality monitoring needs of Ontario’s hundreds of smaller communities in rural and northern Ontario. There was some variations in what the ECO heard from communities interviewed – the wish list was not uniform – but there was a strong message that municipalities need better information on local air quality.
Municipalities need to make a multitude of decisions that can have an impact on local and regional air quality and on human health. For example, municipalities have considerable influence over: the density and design of subdivisions, the siting of homes, schools, day care centres, bike paths and truck depots; the mode and design of transportation routes; and the purchasing of street sweeping equipment and transit buses. Municipalities are looking to MOE for leadership assessments of local airsheds and micro-environments; the ministry is seen as the agency with both the technical expertise and regulatory authority to address ambient air quality.
At a minimum, municipalities expect MOE to continue to lead on regulating large point sources, such as industrial sites, but they would like the ministry to consider these sites with a view to the cumulative impacts of these emission sources on local air quality. Municipal representatives observed that MOE’s role in air quality protection needs to evolve, to address not only large point sources, but also the cumulative impacts of mobile and area sources, such as traffic corridors and residential home heating. As municipalities become increasingly intensified, we are bound to see growing public pressure to maintain acceptable air quality in highly urbanized settings. In order to effectively manage urban air quality, we will certainly need to assess it.
| High-Traffic Areas in Sudbury |
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| For several years, the ECO has been commissioning summer sampling of street level air quality at selected locations, focusing on particulates and ground level ozone. In 2009, this project added five busy intersections in the City of Greater Sudbury, at the request of Clean Air Sudbury, a non-profit community group. The results of the 2009 sampling in Sudbury suggest that concentrations of fine particulates (PM2.5) at street level near busy intersections can at times be substantially higher than concentrations measured at Sudbury’s MOE regional air quality monitoring station. The consultant’s report on this sampling study can be found on the ECO’s website (click here for more information). |
| Previous section: Not Airtight: Amendments to Ontario’s Air Quality Regulation |
| Next section: A Watershed Moment? Ontario Introduces the Lake Simcoe Protection Plan |
| This is an article from the 2009/10 Annual Report to the Legislature from the Environmental Commissioner of Ontario. |
Citing This Article:
Environmental Commissioner of Ontario. 2010. "How’s the Air on Your Street?." Redefining Conservation, ECO Annual Report, 2009/10. Toronto, ON : Environmental Commissioner of Ontario. 99-101.
