Case Studies

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.



Search Case Study Results (e.g., Water body name, state)
Analysis Approach
Nutrient Parameter
Water Body Type

Florida’s Streams

Florida’s Lakes

NNC Sequence in Texas

NNC Sequence in Mississippi

NNC Sequence in Georgia

Wisconsin Streams

Minnesota Lakes

Maine Fresh Surface Water

Lower Yellowstone River, MT

Lake Pepin Criteria, MN

Yaquina Estuary, OR

Klamath River

Beaver Lake

Remote Sensing in FL

Pensacola Bay

Coastal Bays in MD and VA

Barnegat Bay-Little Egg Harbor

Yaquina Estuary

San Francisco Bay

Nutrients in Neuse River Estuary

Nutrients in Chesapeake Bay

Nutrients in Delaware Estuary

Nutrients in Narragansett Bay

North Bosque River Nutrient Targets

Lake Waco Restoration Targets

NH Estuaries Project: Shellfish

NH Estuaries Project: Env. Indicators

San Francisco Estuary Indicators

Salmon Habitat Indicators

Ecological Indicators

This website is in beta. Information on this website is not final and is subject to change