Nutrient enrichment is one of the leading causes of surface water quality impairment in the U.S. The adoption of numeric nutrient criteria in state water quality standards for the protection of aquatic life is a high priority for EPA’s Office of Water.
EPA's Office of Water has requested SAB review of the Agency’s draft Technical Guidance on Empirical Approaches for Numerical Nutrient Criteria Development. This draft guidance would supplement EPA's published technical guidance for developing numeric nutrient water quality, which focuses on the use of reference conditions for deriving nutrient criteria. The draft guidance responds to the interest of many states in using empirically-derived stressor-response relationships as the basis for developing numeric nutrient endpoints for water quality standards.