This library is a compilation of the case studies that are highlighted at the bottom of relevant pages throughout this N-STEPS Online tool. The case studies provide examples of decisions that states made during specific stages of the numeric nutrient criteria development process.

Click on each card below to open a case study summary. For more detail, refer to the original sources, which are cited and accessible in the resource library. Results can be filtered using the Search feature, and also by clicking water body, parameter, and analysis approach icons.

For progress on the adoption of numeric nutrient criteria for all states and territories, please visit EPA’s Nutrient Policy and Data page.