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Technical Support for Numeric Nutrient Water Quality Criteria Development

EPA has developed a number of resources to help states with developing criteria. In March 2011, EPA issued a comprehensive framework to assist states, territories and tribes in addressing nitrogen and phosphorus pollution. With respect to the framework, our goal is to assist in the development of numeric nitrogen and phosphorus criteria, which will help states, territories, and tribes move toward adopting water quality standards for nitrogen and phosphorus. Additionally, EPA has published technical resources, such as technical guidance documents that describe the techniques for developing numeric criteria for nitrogen and phosphorus pollution for different water bodies, technical documents describing ecoregional criteria, online databases and clearinghouses, and data concerning impaired waters and TMDLs.

Reference Documents

Other Resources