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CADDIS Volume 1

Biological Assessment and Biocriteria


The use of biological assessments and biocriteria in state and tribal water quality standards programs is a top priority of the U.S. Environmental Protection Agency (U.S. EPA's biocriteria website).

For that reason, one of the Agency's objectives is to ensure that all states and tribes develop water quality standards and programs that:
  • Use bioassessment information to evaluate the condition of aquatic life in all waterbodies,
  • Establish biologically-based aquatic life use designations,
  • Protect aquatic life use standards with narrative or numeric biocriteria,
  • Regulate pollution sources, Assess the effectiveness of water quality management efforts, and
  • Communicate the condition of their waters.