Animal manure, excess fertilizer applied to crops and fields, and soil erosion make agriculture one of the largest sources of nitrogen and phosphorus pollution in the country.

Excess nitrogen and phosphorus (nutrients) are among the most prevalent cause of water quality impairment in the United States. Research at EPA provides innovative solutions to address the problem of nutrient pollution in the Nation’s air, water and land. Researchers are:

• Studying the sources of nutrient pollution and harmful algal blooms
• Determining where they go and how they move in the environment
• Evaluating the chemical changes that happen as they move in the environment
• Studying the effects on our environment and health
• Evaluating the benefits and costs associated with different nutrient management choices

How do we protect and sustain our water, land and air and protect our health while also providing the material, food, and energy required by society? To help answer this question, researchers are exploring solutions to:

• Reduce and control nutrient pollution and harmful algal blooms
• Maximize efficient nutrient use
• Promote nutrient removal processes
• Protect people and natural resources

Much of this research supports the development of regulatory limits on nutrient pollution in water resources. At the same time, researchers work to understand the social and economic costs and benefits associated with potential solutions to excess nutrient problems so that optimal solutions for managing water quality over the long term can be achieved.

For an overview of the nutrient pollution problem, its causes, solutions, and what steps you can take to help, visit EPA’s Nutrient Pollution page.

Research Topics

• Climate Change and Nutrient Interaction
• Harmful Algal Blooms & Cyanobacteria
• Monitoring & Remote Sensing
• Nitrogen Deposition and Nutrient Modeling
• Nitrogen Mapping
• Nutrient Management Case Studies
• Nutrient Recovery
• Sustainable Watersheds and Nutrient Pollution

​Science Inventory Resources

The Science Inventory is a searchable database of research products primarily from EPA's Office of Research and Development. See: all Science Inventory resources.​

• Science Inventory "Nitrogen OR Phosphorus" Search Results

Tools

• Water Quality Analysis Simulation Program (WASP)
• Causal Analysis/Diagnosis Decision Information System (CADDIS)

Featured Stories

• Science Matters: Nutrients: How much is too much?
• Science Matters: Nutrients in Narragansett: Improving Understanding and Communication
• Science Matters: Partnerships to Protect Chesapeake Bay
• Science Matters: Into the Dead Zone
• Science Matters: Showing Buried Streams the Daylight
• Science Matters: Down the Drain: Wetlands as Sinks for Absorbing Reactive Nitrogen
• Science Matters: What’s Ailing Your Stream? CADDIS Can Help You Find Out