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Nutrient Management (NM)

Phosphorus and Water

Water Quality: Nutrient Criteria for Phosphorus (P)

The Environmental Protection Agency (EPA) requires states and authorized tribes to develop and publish water quality standards that protect the nation’s waters from over-enrichment associated with human activities. EPA has published nutrient benchmarks. These provide guidance for states in the development of their nutrient standards. Phosphorus is usually been attributed to be the limiting nutrient for growth of plants in water bodies; thus, development of nutrient criteria and standards for protection of surface waters is crucial. Usually, total P and phosphate are used for measurement and determination of P in surface waters. A challenge in developing nutrient criteria is to establish levels that protect water quality but are also achievable at acceptable costs.

Educational Resources

EPA Nutrient Criteria Fact Sheet

US EPA Nutrient Water Quality Criteria

EPA Summary Table for the Nutrient Criteria Documents

Nutrient Stream Study

Extension Publications

Agricultural Phosphorus Management and Water Quality Protection in the Midwest

Scientific Review Articles

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National Water Program

A cooperative program consisting of the USDA Cooperative State Research, Education, and Extension Service and the Land Grant Colleges and Universities.

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- This material is based upon work supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under Agreement No. 2008-51130-19526.

Photograph by Tom Schultz, Department of Natural Resource Ecology and Management, Iowa State University

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