The ABC's of Air Pollution in the Lower Fraser Valley

The haze that often blankets the Lower Fraser Valley makes air quality a visible concern in our region. As we strive to protect our health and the environment, it is important to understand the reasons why our air quality is degraded, as well as the sources of air contamination. This work is supported by many agencies that conduct scientific research on complicated air quality issues.

Important sources of information include the air pollution emission inventories that are prepared by the Greater Vancouver Regional District (GVRD) in the Lower Fraser Valley. The GVRD first completed this work in the Lower Fraser Valley airshed in 1985, and has recently updated this information in the year 2000 inventory.

The Lower Fraser Valley airshed encompasses virtually the entire GVRD, as well as the southwestern, more populated portions of the Fraser Valley Regional District. Whatcom County in Washington State was also included in the latest inventory. The inventory identifies the sources and trends for six common air contaminants in the airshed, as well as the main sources of greenhouse gases.

As our population and demand for energy continue to increase, important scientific work such as these inventories provide better tools to help our decision-making about future development and strategies to control emissions. This information shows that our activities are largely responsible for the degradation of air quality in the Lower Fraser Valley airshed; while light-duty vehicles are still the main source of pollution, marine vessels— including freighters and cruise ships—are also contributing to air pollution in this region.

Common Air Pollutants

When we think of pollution, we usually think of smog. Smog—or smoke and fog—is the haze that results when air contaminants mix and react in the atmosphere. One of the harmful byproducts of this process is ozone. Ground-level ozone and air contaminants can seriously affect human health and the environment. Air quality management has traditionally sought to reduce the concentration of “common air contaminants,” which include:

• Particulate Matter (PM)
  • PM₁₀ – inhalable particulate matter
  • PM_2.5 – fine particulate matter
• Nitrogen Oxides (NOx)
• Sulphur Oxides (SOx)
• Volatile Organic Compounds (VOC)
• Carbon monoxide (CO)
• Ammonia

Greenhouse Gases

Naturally occurring greenhouse gases (such as water vapour, carbon dioxide, methane and nitrous oxide) keep the Earth warm enough to support life. Scientific studies show that a variety of human activities also release greenhouse gases. These include the burning of fossil fuels for electrical energy, heat and transportation. Burning fossil fuels—such as coal, oil and gas—releases carbon dioxide, the most significant greenhouse gas. By increasing the concentration of present greenhouse gases and by adding new ones like perfluorocarbons and HFCs (alternatives to CFCs), human activities can raise the average global temperature.

Levels of both common air contaminants and greenhouse gases contribute to the overall air quality picture in the region. For example, cars and other light-duty vehicles emit 24% of the total greenhouse gas emissions, and 23% of total volatile organic compounds, a common air contaminant.

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Sources of Air Pollution

Air quality managers categorize the sources of pollution as mobile, point or area sources. In urban communities such as the Lower Fraser Valley, the main sources of air emissions are usually mobile (e.g., cars and trucks) or area (e.g., residential heating) sources. In rural communities, such as Prince George or Williams Lake, point sources are usually the main source of air emissions (e.g., sawmills). Personal choices in areas such as home heating and transportation can make a difference to the overall air quality picture.

Mobile Sources

Mobile sources include both on-road and non-road vehicles and engines including aircraft, rail, marine vessels and engines. The on-road category includes light-vessels and agricultural, construction, recreational and duty vehicles (passenger cars, smaller trucks and motor-lawn and garden equipment) and heavy-duty vehicles (large trucks and buses).

Point Sources

Point sources include large industrial facilities operating under an air discharge permit issued from the GVRD or the BC Ministry of Water, Land and Air Protection.

Area Sources

Area sources include smaller, broadly distributed light industrial, commercial, institutional, residential, agricultural or naturally occurring sources that normally do not require an air discharge permit. For example, residential furnaces and wood stoves contribute 8% of total particulate matter, while space heating contributes 22% of total CO₂.

While air quality is threatened by a variety of pollutants from both natural and man-made sources, most emissions come from a limited number of sources in the Lower Fraser Valley:

• Light-duty vehicles account for 63% of the CO emissions;
• Natural sources, light-duty vehicles and solvent evaporation account for 70% of VOC emissions;
• Marine vessels are the largest contributors of SOx in the region (33%);
• Agricultural sources contribute 77% of the ammonia;
• Area sources account for the majority of PM emissions;
• Cars and light-duty trucks emit 20% of the smog-form-ing pollutants; and,
• The largest emitters of greenhouse gases include light-duty vehicles (24%), residential and commercial/insti-tutional space heating (20%), and electric power generation (15%). Together, these sources accounted for 59% of greenhouse gas emissions in the Lower Fraser Valley in 2000.

The following charts illustrate the year 2000 emissions inventory of smog-forming pollutants and nitrogen oxide emissions within the Lower Fraser Valley (which includes GVRD and FVRD data).

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Keeping Air Clean

Through all levels of government, environmental agencies, community groups and individual efforts, many initiatives are underway to mitigate emissions of air contaminants and greenhouse gases in the Lower Fraser Valley (see "Working Together for Cleaner Air”). For example, the GVRD emissions inventories help us to set benchmarks from which we can measure our progress in reducing air pollution, while keeping clean areas clean.

Scientific data helps us to know what approaches are working and where new strategies should be applied. Because light-duty vehicles are one of the greatest contributors to pollution, programs like the Government of Canada’s 10-year Agenda on Cleaner Vehicles and Fuels, AirCare, advances in fuel efficiency, improved fuel formulation and transportation alternatives will greatly influence the future air quality picture. Continued efforts such as these will be necessary to ensure that our air quality does not degrade.

We can also monitor and evaluate urban planning decisions, including those made by our neighbours to the south. Since local air quality is determined by all sources emitting into the airshed, joint efforts such as the Georgia Basin/Puget Sound International Airshed Strategy are vital as we strive to keep clean air clean.

Such initiatives are particularly important for the Georgia Basin area of British Columbia and the Puget Sound area of northern Washington State. Despite being on either side of our international boundary, these areas share a common airshed. This area is projected to have nine million residents by 2020, a 50% increase from today’s population.