You are here:
Nutrient Criteria Research
Impact/Purpose:
Water Quality MYP
Description:
EPA has developed methodologies for deriving nutrient criteria, default criteria for the variety of waters and eco-regions found in the U.S., and a strategy for implementing the criteria including guidance on the use and development of biocriteria. Whereas preliminary research has been completed, the following areas have been identified by OW as requiring additional understanding to improve the ability of EPA, the States and Tribes to manage coastal aquatic resources. Research in this track will be aimed at developing biological response indicators for nutrient criteria development for coastal habitats, specifically a need to: Developing comparative assessments to understand resource (estuary and wetland) vulnerabilities and sensitivities to nutrients, including increased understanding of between and within system variability, between habitat sensitivities and of ecosystem responses along nutrient gradients Determining loading levels and seasonal delivery regimes under which nutrient inputs to coastal systems shift from being ecologically beneficial to detrimental, and develop threshold criteria for these transitions that account for multiple stressor interactions such as nutrients combined with sediments Determining loading levels and seasonal delivery regimes for, and among, different/multiple cultural source of nutrients (industrial, municipal, nonpoint (urban, suburban, agricultural, silviculture, aquaculture, and atmospheric) Developing implementation guidance for recommended criteria and proposed standards In addition, research in this track will support the development of numeric nutrient standards as a baseline for TMDL development, NPDES permitting, and water quality trading to: Identify improved scientifically defensible approaches (including approaches based on classification of systems that respond similarly, weight of evidence from multiple sources, modeling and associated uncertainty analyses) for developing numeric nutrient criteria, including the use of translator models that relate nutrient inputs to ecosystem response. Identify the best methods for implementing standards in a cost effective manner, including the incorporation of spatial and temporal aspects of implementation of criteria protective of designated uses. Provide scientific support for TMDL development, nutrient trading, NPDES permitting, and integration with other water quality programs, including tiered aquatic life use and biological criteria