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Salish Sea

Air Quality


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13 of the 14 air monitoring stations in our study meet both Canadian and U.S. standards, and air quality is generally improving thanks to new actions in Washington and British Columbia that control sources of air pollution.

The EPA and Environment and Climate Change Canada have set air quality standards for fine particulate matter such as those found in smoke or haze.

These fine particles - also called PM2.5 because they are 2.5 micrometers in diameter or less - are 100 times smaller than the width of a human hair.

Fine particles can be inhaled deeply into a person's respiratory system and cause severe health problems. It also contributes to poor visibility and can impact the function of the ecosystem.

What's happening?

Levels of fine particulates at 13 of the 14 air monitoring stations shown in the map below meet both the Canadian Ambient Air Quality Standard and the U.S. Daily Standard. Levels of fine particulates in south Tacoma exceed the more stringent Canadian Ambient Air Quality Standard but meet the U.S. Daily Standard.

Between 2005 and 2013, 12 of the stations showed improving conditions. Increases in the two remaining stations were not significant enough to cause exceedances of Canadian or U.S. standards, and may have been due to the installation of new instruments that are more sensitive to fine particulates.

  • List of air monitoring station locations in our study
    Map of Salish Sea air monitoring stations
    Locations of the 14 air monitoring stations studied in this report.
    • Bellingham, Washington
    • Burnaby South, British Columbia
    • Chilliwack, British Columbia
    • Hope, British Columbia
    • Lake Forest Park, Washington
    • Marysville, Washington
    • Nanaimo, British Columbia
    • Pitt Meadows, British Columbia
    • Port Townsend, Washington
    • Seattle (Duwamish), Washington
    • Seattle (South Park), Washington
    • Tacoma, Washington
    • Vancouver, British Columbia
    • Victoria, British Columbia

Why is it important?

Air quality can affect human health, the environment and the economy. Fine particulates are of special interest for two reasons:

  • They are able to penetrate deep into the respiratory system and impact human health.
  • They scatter light very efficiently, they play a major role in reducing visibility.

There is no known lower threshold for human health effects. Current levels of fine particulates have been found to have measurable effects despite the fact that air quality in the Salish Sea ecosystem appears to be relatively good in comparison with other urban regions in North America.

Fine particulates can aggravate existing respiratory and cardiovascular disease, reduce lung function, increase respiratory symptoms, and lead to premature death. They may also provide a way for toxics - including carcinogens - to get deep into a person's respiratory system.

While visibility is often considered of secondary importance compared to the human health effects, an observed reduction in visibility due to smog or haze is typically interpreted by the public as air pollution. Because tourism is a key economic sector in the Salish Sea ecosystem where visitors are attracted to spectacular coastal vistas, reduced visibility can obscure these vistas and negatively affect tourism.

  • Learn more about why it's important

    Economic Impact

    The economic benefits of reducing fine particulates are also significant. The Border Air Quality Study - an economic assessment led by the University of British Columbia - estimated that a 1% improvement in PM2.5 would yield $29 million in annual savings in the Lower Fraser Valley in 2010.

    In Washington, the total annual costs estimated for adult and childhood asthma was $127.8 million in 2004. This estimate reflects asthma cases attributable to environmental contaminants such as PM2.5 and includes both direct health care costs and indirect costs, such as lost productivity and premature death.

    In British Columbia, direct medical costs for asthma were estimated at $42 million in 2000.

Why is it happening?

Particulate matter can be directly emitted into the atmosphere or formed within the atmosphere. Sources may be natural (for example sea spray, blowing dust, tree pollen, forest fires) or caused by human activities (such as construction, wood and fossil fuel combustion).

Within the Salish Sea ecosystem, the main human sources of particulate matter are transportation (cars, trucks, trains, ships) and woodstoves and fireplaces - particularly during winter months.

  • Learn more about why it's happening

    In 2005, an air emissions inventory of Vancouver, the southwest portion of the Fraser Valley, and Whatcom County looked at air pollution from various sources.

    Mobile sources (such as cars and other on-road vehicles, trains, and ships) and area sources (such as woodstoves and commercial boilers) represent over 70% of fine particulate emissions.

    Point sources (such as large industrial facilities) and road dust contribute the remaining 30%.

    Chart showing sources of fine air particulate emissions in MetroVancouver, Fraser Valley, and Whatcom County.

    Chart showing trends in fine air particulate emissions by source in the Lower Fraser Valley since 1990 and projected to 2030.

What are we doing about it?

The Georgia Basin-Puget Sound International Airshed Strategy (IAS) is a multi-agency, international co-operative effort to address shared air quality management concerns through co-operation and information exchange. This strategy also aims to prevent future deterioration of air quality, which is particularly important due to significant regional population growth that is expected to continue for at least the next two decades.

Key activities under the IAS include the following:

  • Prioritizing air quality issues for action by the IAS Working Groups.
  • Forecasting future air quality conditions in the airshed.
  • Improving the efficiency of air quality data exchange among agencies.
  • Improving information exchange and notification procedures for significant new sources of transboundary air pollution.
  • Collaborating on regulations to ensure cleaner vehicles and fuels in the region.

Individually, agencies are focused on actions to reduce emission sources from the following sources:

  • Locomotives and rail yards.
  • Marine vessels and port operations.
  • Wood burning.
  • Vehicles and non-road engines.
  • Learn more about what we're doing

    Below are some examples of actions to reduce emission sources of fine particulates:

    Emission Control Areas in Coastal B.C. and Washington

    In 2010, the International Maritime Organization accepted a joint Canada-U.S. application to designate parts of coastal waters in B.C. and Washington as Emission Control Areas. These areas have more strict standards for marine fuels, as well as sulphurous oxide and nitrogen oxide emissions.

    In response, Canada amended its regulations for vessel pollution and dangerous chemicals under the Canadian Shipping Act.

    Wood Smoke Reduction Efforts in Washington

    Washington has some of the most progressive wood smoke reduction laws in the U.S.

    Wood and pellet stoves sold in Washington must be nearly twice as clean as the national EPA emission standard. Washington also regulates factory-built fireplaces, masonry heaters and other solid fuel burning devices, and does not permit the sale or installation of outdoor wood-fired boilers.

    Burn bans, fuel restrictions (such as no garbage burning) and wood fuel moisture requirements have been in use since 1995.

    British Columbia Wood Stove Exchange Program

    The B.C. Wood Stove Exchange Program provides financial incentives for upgrading old wood stoves. It also provides education to wood burners on how to improve their burning practices.

    In 2014, the provincial government provided $200,000 to support wood stove exchange programs in 13 communities. This funding provided incentives for replacing 700 old smoky wood stoves and education on clean wood burning practices.

    Emissions from Non-Road Diesel Engines in Metro Vancouver

    New operating prohibitions came into force in 2015 under Metro Vancouver’s Non-Road Diesel Engine Bylaw which has been in effect since 2012. Under the new bylaw, owners and operators of older industrial and construction machines such as excavators, forklifts and generators are required to register and pay fees for engines with no or rudimentary controls. Unregistered engines are prohibited from operating.

    Metro Vancouver also offers rebates of up to 80% fees if older engines are retired or upgraded. Port Metro Vancouver launched a similar program for port tenants in 2015.

  • A history of U.S.-Canada collaboration on air pollution in the Salish Sea airshed

    The first significant case of U.S.-Canadian transboundary air pollution, the Trail Smelter Arbitration, also created a global precedent. The smelter began operations in the 1890s in southern British Columbia, near the U.S. border. Soon after, nearby farmers in Washington State complained that sulphur dioxide (SO2) emissions from the plant were damaging their land, livestock, and businesses.

    The dispute was pursued through a lengthy legal process that culminated in the Trail Smelter Arbitration. The most important result from this arbitration, which concluded in 1941, was the finding that "no nation may undertake acts on its territory that will harm the territory of another state" - a global precedent in the area of transboundary air pollution.

    Another binational environmental effort between Canada and the United States is the International Joint Commission, which was formed in 1909 as part of the Boundary Waters Treaty. Though the Commission originally dealt with water-related issues, it now also considers air quality matters as well, such as the 1991 U.S.-Canada Air Quality Agreement (see below).

    One of the most important transboundary air quality accomplishments was the United Nations Economic Commission for Europe (UNECE) Convention on Long-range Transboundary Air Pollution.

    The need to address regional acid rain was motivation for the Convention, which was signed by 34 Governments and the European Community in 1979. It was the first international legally binding instrument to deal with problems of air pollution on a broad, regional basis.

    Besides laying down general principles of international cooperation for air pollution abatement, the Convention sets up an institutional framework bringing together research and policy.

    Following important American and Canadian efforts toward improved air quality, both countries met to discuss cross-border air pollution, and develop the 1991 U.S.-Canada Air Quality Agreement. This agreement was designed address shared concerns regarding transboundary air pollution.

    At the province/state level, the 1992 Environmental Cooperation Agreement (PDF)(4 pp, 265 K, About PDF) was signed between Washington State and the Province of British Columbia. This agreement emphasized coordinated action and information sharing on environmental matters of mutual concern including air quality.

    In 1994, a Memorandum of Understanding was signed between these agencies, as well as the Greater Vancouver Regional District and Northwest Air Pollution Authority, to ensure timely prior consultation on air permitting.

    In December 2000, Canada and the United States negotiated the Ozone Annex under the 1991 U.S.-Canada Air Quality Agreement. The annex includes commitments by both countries to dramatically reduce the smog-causing pollutants, nitrogen oxides (NOx) and volatile organic compounds (VOCs) that cause ground level ozone to form that can harm human health and the environment.

    Also in 2000, Environment and Climate Change Canada and the EPA signed a Joint Statement of Cooperation on the Georgia Basin and Puget Sound Ecosystem. The Statement of Cooperation outlines common goals and objectives, confirms the commitment and leadership of the two federal governments and recognizes the special interests of residents and their governments. This agreement also gave rise to the Transboundary Ecosystem Indicators project (now called the Health of the Salish Sea Ecosystem Report).

    In December 2001, the EPA's Administrator Christine Todd Whitman and EPA Region 10 Administrator John Iani, both expressed their continued support for this important transboundary initiative to Environment Minister David Anderson and Washington Governor Gary Locke. Cooperative discussions between U.S. and Canadian partners continued, culminating in the 2002 Statement of Intent on a Georgia Basin-Puget Sound International Airshed Strategy that pledges continued collaborative efforts regarding present and future air quality issues in the Georgia Basin-Puget Sound airshed.

    List of partners to the Georgia Basin-Puget Sound International Airshed Strategy

    • U.S. EPA
    • Environment and Climate Change Canada
    • Washington Dept. of Ecology
    • Health Canada
    • Washington Dept. of Health
    • B.C. Ministry of Environment
    • B.C. Ministry of Agriculture
    • Puget Sound Clean Air Agency
    • Northwest Clean Air Agency
    • Olympic Clean Air Agency
    • Fraser Valley Regional District
    • Whatcom Conservation District

Five things you can do to help

  1. Walk or ride a bike when possible, or take public transportation.
  2. Ask your energy supplier for a home audit to find ways to help you save energy and money.
  3. Have your gas appliances and heater regularly inspected and maintained.
  4. Turn off office equipment, computers, printers, and fax machines at night or after hours.
  5. During the day open the blinds and turn off the lights. Dress in layers instead of reaching for the thermostat.

Learn more about this topic

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Scientific references

The following links exit the site Exit
  1. Bates, D.V., J. Koenig, M. Bauer. 2003. Health and Air Quality 2002 Phase 1 Methods for Estimating and Applying Relationships between Air Pollution and Health Effects. Prepared for British Columbia Lung Association.
  2. BC Lung Association. 2010. State of the Air 2010.
  3. BC Ministry of Environment. 2014. Air quality in the Capital Regional District 2012. Environmental Protection, Coast Region, Nanaimo, BC.
  4. BC Ministry of Environment. 2015. Georgia Strait Air Zone Report (2011-2013). Clean Air Unit. Victoria, BC.
  5. BC Ministry of Environment. 2015. Lower Fraser Valley Air Zone Report (2011-2013). Clean Air Unit. Victoria, BC.
  • More references
    1. Border Air Quality Strategy. 2005. Maintaining air quality in a transboundary air basin: Georgia Basin-Puget Sound. Canada – United States Air Quality Agreement. Prepared for Environment Canada and US Environmental Protection Agency.
    2. Border Air Quality Study. 2008. Summary Findings from the Border Air Quality Study. University of British Columbia, University of Victoria and University of Washington.
    3. Canadian Council of Ministers of the Environment. 2012. Canada-Wide Standards for Particulate Matter and Ozone. 2012 Final Report. PN 1526. ISBN 978-1-77202-009-0 PDF. Winnipeg, Manitoba.
    4. Canadian Council of Ministers of the Environment. 2012. Guidance Document on Achievement Determination of Canadian Ambient Air Quality Standards for Fine Particulate Matter and Ozone. PN 1483. 978-1-896997-91-9 PDF. Winnipeg, Manitoba.
    5. CCME, 2000. Canada Wide Standard for PM.
    6. Crane Management Consultants. 2005. Socio-Economic Considerations of Cleaning Greater Vancouver’s Air. Prepared for the Greater Vancouver Regional District.
    7. Davies, K. 2005. Economic Costs of Diseases and Disabilities Attributable to Environmental Contaminants in Washington State. Prepared for the Collaborative for Health and Environment – Washington Research and Information Working Group.
    8. Environment Canada and US Environmental Protection Agency. 2014. Georgia Basin - Puget Sound Airshed Characterization Report, 2014. Vingarzan R., So R., Kotchenruther R., editors. Environment Canada, Pacific and Yukon Region, Vancouver (BC). U.S. Environmental Protection Agency, Region 10, Seattle (WA). ISBN 978-1-100-22695-8. Cat. No.: En84-3/2013E-PDF. EPA 910-R-14-002.
    9. Environmental Protection Agency. 2009. Integrated Science Assessment for Particulate Matter. Environmental Protection Agency, Research Triangle Park, NC. EPA/600/R-08/139F.
    10. EPA. 2006. National Ambient Air Quality Standards for Particulate Matter. Federal Register. 40CFR Part 50 (EPA-HQ-OAR-2001; FRL-8225-3; RIN 2060-AI44).
    11. EPA-EC. 2002. Transboundary Ecosystem Indicators.
    12. EPA-EC. 2005. Transboundary Ecosystem Indicators.
    13. Grantz, D.A. 2003. Ecological effects of particulate matter. Environment International. 29(2003): 213-239.
    14. McNeill, R. and A. Roberge. 2000. The Impact of Visual Air Quality on Tourism Revenues in Greater Vancouver and the Lower Fraser Valley. Environment Canada. Georgia Basin Ecosystem Initiative Report Number EC/GB-00-028.
    15. Metro Vancouver. 2010. 2005 Lower Fraser Valley Air Emissions Inventory, Forecast and Backcast – Detailed Listing of Results and Methodology.
    16. MetroVancouver. 2007. 2005 Lower Fraser Valley Air Emissions Inventory and Forecast and Backcast. December 2007.
    17. MetroVancouver. 2013. 2010 Lower Fraser Valley Air Emissions Inventory and Forecast and Backcast – Final Report and Summarized Results. September 2013.
    18. MetroVancouver. 2015. Caring for the Air. Air Quality Management.
    19. Ross and Associates Environmental Consulting. 2007. Northwest Ports Clean Air Strategy. Prepared for the Port of Seattle, Port of Tacoma and Vancouver Port Authority.
    20. Ross and Associates Environmental Consulting. 2009. Northwest Ports Clean Air Strategy: 2008 Implementation Report. Prepared for the Port of Seattle, Port of Tacoma and Vancouver Port Authority.
    21. RWDI Air Inc. 2005. Health and Air Quality 2005 – Phase 2: Valuation of Health Impacts from Air Quality in the Lower Fraser Valley Airshed. Vancouver, BC.
    22. Sadatsafavi, M. 2010. Direct health care costs associated with asthma in British Columbia. Can Respir J. 17(2): 74-80.
    23. Thomson, B. 2004. Characterization of the Georgia Basin Puget Sound Airshed. Environment Canada and United States Environmental Protection Agency.
    24. Vingarzan, R., 2010. LFV Visibility Pilot Science Summary. Report prepared for the British Columbia Visibility Coordinating Committee, June 2010. Environment Canada, Meteorological Services of Canada, Pacific and Yukon Region, #201-401 Burrard Street, Vancouver, BC.