The application of nitrogen fertilizer in the fall or on frozen soils will be restricted to quarter-sections of land where 50 percent or more of the quarter-section is in an area with vulnerable groundwater and in DWSMAs that have nitrate-nitrogen concentrations at or in excess of 5.4 mg/L nitrate-nitrogen. An area with vulnerable groundwater is an area where nitrate can move easily through soil and into groundwater, contaminating drinking water sources. Vulnerable areas for Part 1 of the rule are defined as:

View the interactive Vulnerable Groundwater Area Map To access all of the mapping layers select the layer list icon in the upper left corner of the map page. To view a layer, check the box to the left of the layer title.

The DWSMAs on the map are preliminary and were updated in June, 2019. The list may change. A final map will be posted by January 15, 2020.

The map shapefiles can be downloaded from the Minnesota Geospatial Commons.

A map of the state of Minnesota illustrating the areas where the statewide fall restriction and Drinking Water Supply Management areas are located.