In 2019, the state of Minnesota passed the Groundwater Protection Rule (GPR). GPR will reduce the risk of nitrate from fertilizer leaching into vulnerable groundwater areas. The GPR regulations began January 2020. This article will summarize the rule while providing websites that will give you more specific information.
The GPR is based on the Minnesota Nitrogen Fertilizer Plan (NFMP) which was developed following a multi-year process with extensive stakeholder input. The NFMP outlines the state strategy for preventing contamination and responding to elevated nitrate from fertilizer in groundwater. The rule outlines steps to reduce the severity of the problem in areas where nitrate in public water supply wells is already elevated.
The authority for the rule comes from the Minnesota Groundwater Protection Act, Minnesota Statute 103H. The MDA has the authority to issue administrative, civil, and criminal penalties against those who violate the rule under Minnesota Statute 18D. They regulate nitrogen fertilizer. The Minnesota Pollution Control Agency (MPCA) has the authority to regulate manure.
In January 2020, use of nitrogen fertilizer in the fall and/or on frozen soils will be restricted in areas of the state with vulnerable groundwater with elevated nitrate levels, such as areas with coarse textured soil, shallow bedrock, or karst geology, and in public wellhead areas – known as Drinking Water Supply Management Areas (DWSMAs). Chapter 1573.0030
The GPR is broken down into two parts. Part 1 focuses on the restrictions of the timing and location of applying nitrogen fertilizer. Part 2 responds to DWSMAs which already have elevated nitrate levels. There is a four-level mitigation process in certain cases. Two of the levels are voluntary and the other two levels are regulatory.
Hubbard County falls in the Statewide Fall Restriction with our coarse textured soils. MN Dept. of Ag -Vulnerable Groundwater Area website has more information.
The GPR calls for people to follow the nitrogen fertilizer Best Management Practices (BMPs). The purpose of the BMPs is to protect water quality while at the same time maintaining farm profitability. The BMPs should also be practical to implement. They refer to practices relating to the timing, rate, placement and source of fertilizer application and other practices that increase fertilizer use efficiency and decrease potential loss to the environment. Nitrogen Fertilizer Best Management Practices for Agricultural Lands.
The nitrogen fertilizer BMPs are developed and written by the University of Minnesota after extensive research. The MDA and MPCA adopts the BMPs after a review process and works with University of Minnesota-Extension, agricultural organizations, soil and water conservation districts and others to promote and demonstrate the BMPs. The BMPs are specific to different regions of the state and other practices such as: Pest Control without Pesticide BMPs, Pollinator Habitat BMPs, Turfgrass BMPs and Pesticide BMPs.
A person can also implement Alternative Management Tools such as: planting perennial crops or using seed hybrids, using conservation tillage and residue management, using variable rate technology and possibly enrolling in the Minnesota Agricultural Water Quality Certifications Program (MAWQCP).
One of the BMPs is to properly credit all nitrogen sources, including manure, when determining the nitrogen fertilizer rate. You can find updated publications on manure application rates at: University of Minnesota Extension – Guidelines for Manure Application Rates and MPCA – Manure Application Rate Guide.
There are a few exceptions to the Groundwater Protection Rule. Fall application of nitrogen fertilizer will be allowed in vulnerable groundwater areas to:
- to establish winter grains planted in the fall;
- for fall pasture fertilization;
- for perennial crops;
- for grass seed production;
- for cultivated paddy rice;
- for research on fields 20 acres or less in size, and
- for growing fall cover crops within a potato rotation
See Chapter 1573.0030 for additional exceptions and exemptions.
Please visit the following website to learn more about other frequently asked questions about the Rule.
Please contact our local Minnesota Department of Agriculture Pesticide & Fertilizer Management contacts at the Detroit Lake Office:
Luke Stuewe email is Luke.Stuewe@state.mn.us and phone number is 651-201-6269
Stefan Bischof email is Stefan.Bischof@state.mn.us and phone number is 218-396-0720
If you need extra help with any compliance issues or financial assistance you can get more information about the AgBMP Loan at the MDA website.