The comment period closed Thursday, March 12, 2026. We are currently reviewing the comments received.
The MDA requested written public comments to help determine whether the state’s Groundwater Protection Rule is adequate to protect Minnesota’s air, water, land, and other natural resources from nitrate pollution.
On Sept. 5, 2025 the Ramsey County Second Judicial District Court ordered the MDA to make findings on whether the rule provides sufficient protection, or if additional restrictions are needed.
The Groundwater Protection Rule, adopted in 2019, is designed to minimize nitrate contamination in vulnerable groundwater areas and protect drinking water sources. The rule restricts nitrogen fertilizer application in the fall and on frozen soils. It also establishes a framework for reducing contamination in areas where public water supplies already are experiencing elevated nitrate levels.
The MDA sought information on the following:
- Whether the Groundwater Protection Rule adequately protects against nitrate contamination from regulated practices; or
- Whether further restrictions should be applied to sensitive regions, including Southeast Minnesota’s karst geology and the Central Sands region.
Commenters were asked to provide substantive information and supporting evidence. Comments that state only support for or opposition to the rule will not assist the MDA in its decision-making.
