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Puget Sound

Transboundary Air Quality

Transboundary Air Quality
Introduction Air QualityAir Pollutants EmissionsResearchCrossborder Collaboration Crossborder ActivitiesInternational Air ProgramsEPA Region 10

The quality of the air in the Puget Sound affects the health of the people who live here, the health of the ecosystem, and our ability to enjoy our famous vistas.

The air pollution that degrades our air quality originates from dozens of different activities within the ecosystem, such as driving cars and trucks, manufacturing paper, refining crude oil and burning wood.

An airshed is the air within a particular geographic area. The term “airshed” has been borrowed from aquatic science, in which a watershed is defined as the “land area from which water drains toward a common watercourse in a natural basin.” The Puget Sound Georgia Basin International Airshed refers to the air in the crossboundary coastal regions of Northwest Washington and Southwest British Columbia.

Air pollutants in this transboundary airshed don't recognize the international border. Pollutants can drift from the United States to Canada, and vice versa. For this reason, the organizations that seek to improve the air quality in the region have recognized that they will be more successful if they share information and work cooperatively across the international border. These cooperative activities are leading to better understanding of the science of the airshed and to improved programs that aim to reduce emissions of air pollution.


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