Patterns and Predictions of Drinking Water Nitrate and Nutrient Inventories across the Contiguous U.S.

EPA-ORD-CPHEA's Michael Pennino and Jana Compton, along with Robert Sabo in the Office of Water’s Office of Waters, Oceans and Wetlands, were invited to present on groundwater nitrate at the EPA Region 5 State Source Water Protection Managers Meeting on August 14, 2025.  This meeting brings together EPA Region 5 state source water protection managers to discuss topics of common importance, and there is particular interest in nitrate contamination this year.  Their presentation will outline the temporal trends and spatial patterns in nitrate concentrations and risk of nitrate violation across the US landscape, based on a modeling effort to use EPA's National Nutrient Inventory along with other datasets to predict this risk across the conterminous US, published by Pennino et al. in Science of the Total Environment in 2021.  An example testing the accuracy of these predictions using domestic well data in Oregon will be presented, along with background information about the National Nutrient Inventory.  

Impact/Purpose

EPA-ORD-CPHEA's Michael Pennino and Jana Compton, along with Robert Sabo in the Office of Water’s Office of Waters, Oceans and Wetlands, were invited to present on groundwater nitrate at the EPA Region 5 State Source Water Protection Managers Meeting on August 14, 2025.  This meeting brings together EPA Region 5 state source water protection managers to discuss topics of common importance, and there is particular interest in nitrate contamination this year.  Their presentation will outline the temporal trends and spatial patterns in nitrate concentrations and risk of nitrate violation across the US landscape, based on a modeling effort to use EPA's National Nutrient Inventory along with other datasets to predict this risk across the conterminous US, published by Pennino et al. in Science of the Total Environment in 2021.  An example testing the accuracy of these predictions using domestic well data in Oregon will be presented, along with background information about the National Nutrient Inventory.  The presentation addresses clean water, cooperative federalism and AI.  

Citation

Compton, J., M. Pennino, AND R. Sabo. Patterns and Predictions of Drinking Water Nitrate and Nutrient Inventories across the Contiguous U.S. EPA Region 5 -- Source Water Protection Managers Meeting, virtual presentation, MN, August 14, 2025.