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Scenic views and native vegetation images from parks within North Coast and Cascades Network.

Air Quality at North Cascades National Park

What’s in the Air?

Map of North Cascades National Park in Washington
North Cascades NP, Washington

Most visitors who come to national parks expect clean air and clear views. However, North Cascades National Park (NP), Washington, lies downwind of polluted air from the Puget Sound lowlands and Fraser River Valley of British Columbia, in close proximity to the fast-growing Seattle and Vancouver metropolitan areas. In addition, air masses originating in Asia transport pollutants across the Pacific Ocean and into the park. Air pollutants carried into the park can harm natural and scenic resources such as forests, soils, streams, fish, and visibility.

How is air pollution affecting North Cascades National Park?

  • Nitrogen and sulfur in air pollution are carried by rain, snow, and fog into park ecosystems, threatening sensitive aquatic and terrestrial resources. more »
  • Airborne toxics including mercury and pesticides deposit on park lands and waters, and accumulate in some fish to levels potentially harmful to wildlife and human health. more »
  • Ozone concentrations in the park are low, however, recent trends indicate conditions are degrading. Additionally, there are a number of ozone-sensitive plant species in the park. more »
  • Fine particles of air pollution sometimes cause haze in the park, affecting how well and how far visitors can see vistas and landmarks. more »

What is the National Park Service doing about air pollution at the park?

  • Monitoring nitrogen, sulfur, fine particles and haze to assess status and trends. more »
  • Evaluating the impacts of air pollution on park ecosystems. more »
  • Working with local, state, and federal agencies, including the US Environmental Protection Agency, and industry and public interest groups to develop strategies to reduce air pollution and protect and restore park resources. The NPS also reviews plans for development that may increase air pollution in national parks. more »
  • Using an environmentally friendly alternative fuel vehicle fleet and a shuttle bus for park visitors, reducing the number of vehicles on some of the busiest roads in the park. Learn more about the steps North Cascades NP is taking as part of the Climate Friendly Parks program.

Featured Content

Impacts icon

Pollutants including nitrogen, toxics, ozone, and fine particles affect resources such as streams, soils, and scenic vistas. Find out how on our North Cascades NP Air Pollution Impacts web page.

Studies and Monitoring icon

Studies and monitoring help the NPS understand the environmental impacts of air pollution. Access air quality data and see what is happening with Studies and Monitoring at North Cascades NP.

Related Links

Last Updated: December 30, 2016