Aquatic Life Criteria

States or tribes need to address aquatic life criteria in their water quality standards along with human health, nutrient, and biological criteria.

What are aquatic life criteria? What is the process for deriving criteria values? Find answers to these and many other related questions on supplemental slides (pdf) from the Virtual Water Quality Standards Academy, May 2023 session.

This resource uses information from EPA's Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses (1985), in addition to the revised deletion process for the site-specific recalculation procedure (2013).

These slides are a supplement for those unfamiliar with the subject and a refresher for those with more experience. Session slides are intended to be an interim resource and do not provide the same level of training as the live WQS Academy. Visit the Water Quality Standards Academy page for more information and resources.