Water Quality Standards in the Pacific Northwest and Alaska | Region 10 | US EPA

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Water Quality Standards in the Pacific Northwest and Alaska

What are Water Quality Standards?

Water quality standards are the foundation of the water quality-based control program mandated by the Clean Water Act. Water Quality Standards define the goals for a waterbody by designating its uses, setting criteria to protect those uses, and establishing provisions to protect water quality from pollutants.

A water quality standard consists of four basic elements:

  • designated uses of the water body (e.g., recreation, water supply, aquatic life, agriculture),
  • water quality criteria to protect designated uses (numeric pollutant concentrations and narrative requirements),
  • an antidegradation policy to maintain and protect existing uses and high quality waters, and
  • general policies addressing implementation issues (e.g., low flows, variances, mixing zones).
Recent Actions and Request for Comments

EPA action on Oregon's New and Revised Human Health Criteria.

There are no request for comments active at this time.

Guidance and Methodology

Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards

A Classification of Pacific Northwest Reservoirs with Respect to Nutrient Processing (EPA Region 10, March 2006) (PDF) (26 pp. 1MB). Presents one methodology to classify Pacific Northwest Reservoirs with respect to nutrient processing.

A Classification of Lakes in the Coast Range Ecoregion with Respect to Nutrient Processing (EPA Region 10, December 2005) (PDF) (46 pp. 1.8MB). Presents one methodology to classify natural lakes with respect to nutrient processing.


Local Navigation


URL: http://yosemite.epa.gov/r10/water.nsf/Water+Quality+Standards/WQS+Pacific+NW

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