Partnership and

N-STEPS has resources for wherever you are in the criteria development process. Click below for what's available and where to find it.

What can N-STEPS do for you?


N-STEPS Webcasts Archived: Click here to access archived webcasts.

Nutrient pollution, especially from nitrogen and phosphorus, has consistently ranked as one of the top causes of degradation in some U.S. waters for more than a decade. Click here to connect to EPA's Nitrogen and Phosphorus Pollution site to learn more!

Nutrients in rivers, streams, and aquifers in much of the United States. Click here to connect to USGS's Nutrients National Synthesis Project to learn more!

EPA established final numeric and nutrient water quality standards for Florida lakes and flowing waters. Click here for more more information.

Click here to connect to EPA's Watershed Academy webcasts for using on nutrient management.

Visit the Support Documents page or Click here to access a report linking observational and experimental approaches in nutrient criteria development from Region 6.

Click here for an AQUATOX update.

Welcome to N-STEPS!

The Nutrient Scientific Technical Exchange Partnership & Support Center is a “One Stop Shop” for National, Regional, and Local nutrient criteria developments. The types of assistance available from N-STEPS include:


Technical REQuest System. Figure out what T-REQS does, who should use it, and who the experts are that answer technical questions.

Regional News

Updates about nutrient issues near you!

Questions & Answers

Answers to questions posted through T-REQS.

Analytical and Sampling Tools

Statistical methods, resources, and calculators provided by universities and private organizations.

Nutrient Criteria Information

Provides a variety of support materials, such as: PowerPoint presentations from National and Regional meetings; as well as handy links to useful literature on a variety of topics: Federal nutrient documents, state regional nutrient office contacts & websites, and a searchable bibliography of nutrient criteria topics!


Link to other EPA water quality programs, state nutrient criteria sites, and academic nutrient webpages.


Useful terms defined for the nutrient criteria community.
Disclaimer: The Nutrient Scientific Technical Exchange Partnership and Support website is a partnership among academic, state, and federal agencies to provide technical support to state and tribal agencies for the development of nutrient criteria.